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NEW YORK, SATURDAY, DECEMBER 18, 1880.

NO. 259.

ONE MORE NUMBER.

The next issue will close another volume of this paper, and with it severalthousand subscriptions will expire.

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FIRES—CAUSES AND PREVENTION.

It is estimated that the total annual losses of insured propertyby fire, throughout the world, average nearly twohundred million dollars. Add to this the annual destructionof uninsured property, and we should probably have atotal amounting to quite double these figures. How greatthe loss, how severe the tax upon the productive industryof mankind, this enormous yearly destruction amounts to,will come home to the minds of most readers more directlyif we call attention to the fact that it just about equals thevalue of our total wheat crop during a year of good yield.And it is a direct tax upon productive industry everywhere,because, although here and there a nominal loser, fully insured,has only made what is sometimes called "a goodsale" to the companies holding his risk, this is only a wayof apportioning the loss whereby the community at large becomethe sufferers. Thus it is that we find all ably-managedinsurance companies earnestly endeavoring to make it plainto the public how fires should be guarded against, or mosteffectually localized and controlled when once started.

During the fall, or from "lighting up" time till aboutNew Year's day, more fires occur ordinarily than in anyother portion of the year. This fact points to some of themost general causes of conflagrations—as in the lighting andheating of houses, factories, etc., where this had not beennecessary during the summer months. It is also found thatafter the first of the year the number of fires is greatlydiminished, the lighting and heating arrangements havingbeen subjected to a period of trial during which their mostobvious defects would be remedied. While it may readilybe conceded that the utmost care of the owner of propertycould not totally prevent great average losses from fire—forthe greater the holdings the more must the proprietor trustto the oversight of others—it is evident that the above factsindicate the necessity of more strenuous precautions at thisseason. Gas pipes and fittings should then be tested; furnaceflues and settings looked to; stove, heater, and gratefixtures and connections examined—and in all these particularsthe scrutiny should be most closely directed to parts ordinarilycovered up or out of sight, so that any defect orweakness from long disuse may be exposed. When to theabove causes of fires we have added the extremely fruitfulone found in the extensive use of coal oil within a few yearspast, we have indicated the most common sources of conflagrationsof known origin. An English authority gives thepercentages of different causes of 30,000 fires in London,from 1833 to 1865, as follows: Candles, 11.07; curtains, 9.71;flues, 7.80; gas, 7.65; sparks, 4.47; stoves, 1.67; childrenplaying, 1.59; matches, 1.41; smoking tobacco, 1.40, otherknown causes, 19.40; unknown causes, 32.88. The foregoingfigures do not give the percentage of incendiary fires,>and later statistics would, no doubt, show vastly more firesfrom the use of kerosene than are here attributed to candles.

The prevention of fires, and the best means of minimizingthe loss when they do occur, are topics which cover a widefield, and a collection of the literature on the subject wouldmake a very respectable library. As the question presentsitself to-day, it may well be doubted whether the generalpractice of large property holders of insuring all their possessionsdoes not tend to lessen the constant vigilance whichis the most essential requisite in preventing fires. Thousandsof merchants never mean to keep a dollar's worth ofgoods in store or warehouse that is not fully covered by insurance,and they make this cost a regular charge upon theirbusiness as peremptorily as they do the wages paid the handsin their employ. But few manufacturers can so completelycover their risks by insurance, yet a large portion of themdo so as far as they are able. It does not follow but thatthe larger portion of both merchants and manufacturers exercisewhat the law will fully decide is "due vigilance" inthe care of the property so insured, but it is evident that inmost cases the thoughtfulness is much less complete—thecare wonderfully lacking in personal supervision—as comparedwith what would be the case were each one his owninsurer. Of course, this in no way casts a doubt upon thegeneral policy of business men being amply insured, but infact shows the greater necessity why they should be so, thatthey may not suffer from the carelessness of a neighbor; italso points to the necessity of continually increasing care andthoroughness of inspection on the part of the insurance companies.These agencies, in fact, must compel the insuredto keep up to the mark in the introduction of every improvementto ward off fires or diminish their destructiveness.The progress made in this department during recent yearshas been great. The almost universal use of steam has beenattended by the fitting up of factories with force pumps,hose, and all the appliances of a modern fire brigade; dangerousrooms are metal sheathed, and machinery likely tocause fire is surrounded by stationary pipes from which jetsof water may be turned on instantaneously from the outside;stores and warehouses have standing pipes from which everyfloor may be flooded with water under pressure, and the elevators,those most dangerous flues for rapidly spreading afire, are either bricked in entirely or supposed to be closedat every floor. The latter point, however, is sometimes forgotten,as sea captains forget to keep the divisions of theirvessels having watertight compartments separate from oneanother; the open elevator enlarges a small fire as rapidly asthe open compartment allows the vessel to sink.

With the best of appliances, however, discipline and drillon the part of the hands, in all factories, is of prime importance.It is always in the first stages of a fire that thoroughlyefficient action is necessary, and here it is worth a thousand-foldmore than can be any efforts after a fire is oncethoroughly started. Long immunity is apt to beget a feelingof security, and the carelessness resulting from overconfidencehas been the means of destroying many valuable factorieswhich were amply provided with every facility fortheir own preservation. The teachers in some of the publicschools of New York and Brooklyn, during the past year,set an example which some of our millowners might profitablyfollow. There have been cases when, from a suddenalarm of fire, children have been crushed in their crowdingto get out of the building. The teachers, in the instancesreferred to, marched their children out, under discipline, asif there had been a fire. Let owners of factories try somesuch plan as this, by which workmen may be called upon to>cope with an imaginary fire, and many of them will, we ventureto say, find means of improving their present system orappliances for protection, elaborate as they may at presentthink them to be.

WHAT IS LIGHT?

If on opening a text book on geology one should findstated the view concerning the creation and age of the earththat was held a hundred years ago, and this view gravelyput forward as a possible or alternative hypothesis with thecurrent one deducible from the nebula theory, one wouldbe excused for smiling while he turned to the title page tosee who in the name of geology should write such stuff.Nevertheless this is precisely similar to what one will findin most treatises on physics for schools and colleges if heturns to the subject of light. For instance, I quote from abook edited by an eminent man of science in England, thebook bearing the date 1873.

"There are two theories of light; one theemissive theory;... the other, thevibratory theory;" just as if theemissive or corpuscular theory was not mathematically untenablesixty years ago, and experimentally demonstrated tobe false more than forty years ago. Unless one were treatingof the history of the science of optics there is no reasonwhy the latter theory should be mentioned any more thanthe old theory of the formation of the earth. It is not to bepresumed that any one whose opinion is worth the askingstill thinks it possible that the old view may be the true onebecause the evidence is demonstrable against it, yet whilethe undulatory theory prevails there are not a few personswell instructed otherwise who still write and speak as thoughlight has some sort of independent existence as distinguishedfrom so-called radiant heat; in other words, that the heatand light we receive from the sun are specifically different.

A brief survey of our present knowledge of this form ofenergy will help to show how far wrong the common conceptionof light is. For fifteen years it has been common tohear heat spoken of as a mode of molecular motion, andsometimes it has been characterized asvibratory, and mostpersons have received the impression that the vibratory motionwas an actual change of position of the molecular inspace instead of achange of form. Make a ring of wire fiveor six inches in diameter, and, holding it between the thumband finger at the twisted ends, pluck it with a finger of theother hand; the ring will vibrate, have three nodes, andwill give a good idea of the character of the vibration thatconstitutes what we call heat. This vibratory motion mayhave a greater or less amplitude, and the energy of the vibrationwill be as the square of that amplitude. But the vibratingmolecule gives up its energy of vibration to the surroundingether; that is to say, it loses amplitude preciselyas a vibrating tuning fork will lose it. The ether transmitsthe energy it has received in every direction with the velocityof 186,000 miles per second, whether the amplitude begreat or small, and whether the number of vibrations bemany or few. It is quite immaterial. Theform of thisenergy which the ether transmits isundulatory; that is tosay, not unlike that of the wave upon a loose rope whenone end of it is shaken by the hand. As every shake of thehand starts a wave in the rope, so will every vibration of apart of the molecule start a wave in the ether. Now wehave several methods for measuring the wave lengths inether, and we also know the velocity of movement. Letv =velocity,l = wave length, andn = number of vibrations persecond, thenn =v/l, and by calculation the value ofn varieswithin wide limits, say from 1 × 10¹⁴ to 20 × 10¹⁴. But all[Pg 385]vibrating bodies are capable of vibrating in several periods,the longest period being called thefundamental, and the remainder,which stand in some simple ratios to the fundamental,are calledharmonics. Each of these will give tothe ether its own particular vibratory movement, so that asingle molecule may be constantly giving out rays of manywave lengths precisely as a sounding bell gives out soundsof various pitches at one and the same time.

Again, when these undulations in the ether fall upon othermolecules the latter may reflect them away or they may absorbthem, in which case the absorbing molecules are themselvesmade to vibrate with increased amplitude, and we saythey have been heated. Some molecules, such as carbon,appear to be capable of stopping undulations of all wavelengths and to be heated by them; others are only affectedby undulations of particular wave lengths, or of wavelengths between special limits. In this case it is a speciesof sympathetic vibration. The distinction between the molecularvibrations, and the undulations in ether that resultfrom them, must be kept in mind, as must also the effect ofthe undulations that fall upon other molecules. To one thenameheat is applied, to the other the name ofradiant energyis given; and it matters not whether the undulations be longor short, the same molecule may give out both.

Now let a prism be placed in the path of such rays of differentwave length from a single molecule, and what iscalled the dispersive action of the prism will separate therays in the order of their wave lengths, the longer wavesbeing less refracted than the shorter ones; but the energy ofany one of these will depend upon theamplitude of undulation,which in turn will depend upon the amplitude of vibrationof the part of the molecule that originated it, but ingeneral the longer waves have greater amplitude, thoughnot necessarily so. Consequently, if a thermopile be soplaced as to receive these various rays, and their energy bemeasured by its absorption on the face of the pile, each onewould be found to heat it, the longer waves more than theshorter ones, simply because the amplitude is greater, butfor no other reason, for it is possible, and in certain cases isthe fact, that a short wave has as much or more energy thana longer one. If the eye should take the place of the thermopileit would be found that some of these rays did not affectit at all, while some would produce the sensation of light.This would be the case with any waves having a wavelength between the limits of, say, 1-37,000 of an inch and1-60,000 of an inch; any shorter waves will not produce thesensation of light. If instead of the eye a piece of paperwashed in a solution of the chloride of silver should beplaced where the dispersed rays should fall upon it, it wouldbe found that only the shorter waves would affect it at all,and among these shorter ones would be some of those rayswhich the eye could not perceive at all.

It was formerly inferred from these facts that the heatrays, the light rays, and the chemical rays were different inquality; and some of the late books treating upon this verysubject represent a solar spectrum as being made up of aheat spectrum, a light spectrum, and an actinic or chemicalspectrum, and the idea has often been made to do duty asan analogy in trinitarian theology; nevertheless it is utterlywrong and misleading. There is no such thing as an actinicspectrum; that is, there are no such rays as specialchemical rays; any given ray will do chemical work if itfalls upon the proper kind of matter. For instance, whileit is true that for such salts of silver as the chloride, thebromide, etc., the shorter waves are most efficient; by employingsalts of iron one may get photographic effects withwave lengths much too long for any eye to perceive. Capt.Abney has photographed the whole solar spectrum fromone end to the other, which is sufficient evidence that thereare no special chemical rays. As to the eye itself, certainof the wave lengths are competent to produce the sensationwe call light, but the same ray will heat the face of a thermopileor produce photographic effects if permitted to act uponthe proper material, so there is no more propriety in callingit a light ray than in calling it a heat ray or an actinic ray.What the ray will do depends solely upon what kind of matterit falls upon, and all three of these names,light,heat, andactinism, are names ofeffects of radiant energy. The retinaof the eye is itself demonstrably a photographic plate havinga substance called purpurine secreted by appropriateglands spread over it in place of the silver salts of commonphotography. This substance purpurine is rapidly decomposedby radiant energy of certain wave lengths, becomingbleached, but the decomposition is attended by certain molecularmovements; the ends of the optic nerves, which arealso spread over the retina, are shaken by the disruptingmolecules, and the disturbance is the origin of what we callthe sensation of light. But the sensation is generally a compoundone, and when all wave lengths which are competentto affect the retina are present, the compound effect we callwhite or whiteness. When some of the rays are absent, as,for instance, the longer ones, the optical effect is one we callgreen or greenness; and the special physiological mechanismfor producing the sensation may be either three specialsets of nerves, capable of sympathetic vibration to waves ofabout 1-39,000, 1-45,000, and 1-55,000 of an inch in length,as Helmholtz has suggested, or, as seems to the writer moreprobable, the substance purpurine is a highly complex organicsubstance made up of molecules of different sizes andrequiring wave lengths of different orders to decomposethem, so that a part of the substance may be quite disintegrated,while other molecules may be quite entire throughoutthe visual space. This will account for most of thechromatic effects of vision, for complementary colors, andfor color blindness, by supposing that the purpurine is notnormally constituted. This is in accordance with experimentalphotography, for it has been found that the longwaves will act only upon heavier molecules. It is truevision may be good when there is no purpurine, but thereis no doubt but that this substance is secreted in the eye, andthat it is photographic in its properties, and so far must betaken as an element in any theory of vision; but the chiefpoint here considered is that objectively light does not existindependent of the eye, that light is a physiological phenomenon,and to speak of it otherwise is to confound a causewith an effect. It is, hence, incorrect to speak of the velocityof light; it has no velocity. It isradiant energy thathas the velocity of 186,000 miles a second. It is incorrectto say we receive heat from the sun. What we do receiveis radiant energy, which is here transformed into heat. Thisis not hypercritical, but is in accordance with the knowledgewe have to-day. The old nomenclature we use, butwithout definite meaning; the latter is left to be inferredfrom the connection or context. If a man should attach tothe water main in a city a properly constructed waterwheel,the latter will rotate; but it would not be proper to say thathe received rotation from the reservoir. What he receivedwas water with a certain pressure; in other words, a certainform of energy, which he transforms into rotation by theappropriate means; but by substituting other means he canmake the same water pressure maintain a vibratory motion,as with the hydraulic ram valve, or let it waste itself byopen flow, in which case it becomes ultimately molecularvibration that is heat. The analogy holds strictly. Thetrouble all comes from neglecting to distinguish betweendifferent forms of energy—energy in matter and energy inthe ether.

GLASS SPINNING AND WEAVING.

Quite recently a Pittsburg glass firm has succeeded, to anotable degree, in producing glass threads of sufficient finenessand elasticity to permit of their being woven intofabrics of novel character and quality. Their success issuch as to warrant the assumption that garments of pureglass, glistening and imperishable, are among the possibilitiesof the near future. The spinning of glass threads ofextreme fineness is not a new process, but, as carried on atpresent by the firm in question—Messrs. Atterbury & Co.—possessesconsiderable interest. From a quality of glasssimilar to that from which table ware is made, rods of glassaveraging half an inch in diameter are drawn to any desiredlength and of various colors. These rods are then so placedthat the flame of two gas burners is blown against thatend of the rod pointed toward the large "spinning" wheel.The latter is 81/2 feet in diameter, and turns at the rate of300 revolutions per minute. The flames, having playedupon the end of the glass cylinder until a melting heat isattained, a thread of glass is drawn from the rod and affixedto the periphery of the wheel, whose face is about 12 incheswide. Motion is then communicated, and the crystal threadis drawn from between the gas jets and wrapped upon thewheel at the rate of about 7,500 feet per minute. A higherspeed results in a finer filament of glass, and vice versa.During its passage from the flame to the wheel, a distanceof five or six feet, the thread has become cooled, and yet itselasticity is preserved to a notable degree. The next stepin the process consists in the removal of the layers of threadsfrom the wheel. This is easily accomplished, and afterbeing cut to the desired lengths, the filaments are woven ina loom somewhat similar to that used in weaving silkengoods. Until within the past few weeks only the woof ofthe fabric was of glass, but at present both warp and woofare in crystal. Samples of this cloth have been forwardedto New York and to Chicago, and the manufacturers claimto be able to duplicate in colors, texture, etc., any garmentssent them. A tablecloth of glass recently completed shineswith a satiny, opalescent luster by day, and under gaslightshows remarkable beauty. Imitation plumes, in opal, ruby,pale green, and other hues, are also constructed of thesethreads, and are wonderfully pretty. The chief obstacleyet to surmount seems to lie in the manipulation of thesethreads, which are so fine that a bunch containing 250 is notso thick as an average sized knitting needle, and which donot possess the tractability of threads of silk or cotton.

[The foregoing information is furnished by a correspondentin Pittsburg. A sample of the goods mentioned, a tableclothof glass, is now on exhibition in this city.

The weaving of such heavy fabrics of glass for ornamentalpurposes and for curiosities is no new thing; nor, in our estimation,does comparative success in such experiments warrantthe enthusiastic claims of the Pittsburg manufacturerstouching the adaptability of glass for wearing apparel. Unlessit is in their power to change the nature of glass absolutelyand radically, it does not seem possible for them so toovercome the ultimate brittleness of the separate fibers as tomake the fabric fit to be brought in contact with the skin.The woven stuff may be relatively tough and flexible; butunless the entire fabric can be made of one unbreakable fiberthe touch of the free ends, be they never so fine, must beanything but pleasant or beneficial, if one can judge by thefinest filaments of glass spun hitherto. Besides, in weavingand wearing the goods, a certain amount of fiber dust mustbe produced as in the case of all other textile material.When the softest of vegetable fibers are employed the aircharged with their fragments is hurtful to the lungs; stillmore injurious must be the spiculæ of spun glass.

However, although the manufacturers are likely to be disappointedin their expectation of finding in glass a cheapand available substitute for linen, cotton, and silk in dressgoods, it is quite possible that a wide range of useful applicationmay be found for their new fabric.]

REMARKABLE ERUPTION OF MAUNA LOA.

Late advices from the Sandwich Islands describe theeruption of Mauna Loa, which began Nov. 5, as one of thegrandest ever witnessed. The opening was about six milesfrom the summit of the mountain, and already two greatstreams of lava had been poured out; one of them, fromone to two yards wide and twenty feet deep, had reached adistance of thirty miles. Terrible explosions accompanythe flow of the lava stream, which for a time threatenedthe town of Hilo; at last reports the flow seemed to beturning in another direction.

Mauna Loa, "long or high mountain" occupies a largeportion of the central and southern part of the island ofHawaii, and reaches an elevation of 13,760 feet. It hasbeen built up by lavas thrown out in a highly fluid state, andflowing long distances before cooling; as a consequence theslopes of the mountain are very gentle, averaging, accordingto Prof. Dana, not more than six and a half degrees.Its craters are numerous, and usually occur near the summitand on the sides, new ones opening frequently, andfurnishing, as in the latest instance, magnificent lavastreams. The terminal crater is circular, 8,000 feet in diameter,and in 1864 was about 1,000 feet deep. In 1859 anenormous lava fountain spouted from this crater for four orfive days, throwing a column of white hot fluid lava about200 feet in diameter to the height of two or three hundredfeet. The lava stream ran 50 miles to the sea in eight days.Other great eruptions have occurred in 1832, 1840, 1843,1852, 1855, 1868 and 1873. The lava streams poured out in1840, 1859, and 1868, flowed to the sea, adding considerablyto the area of the island. Those of 1843 and 1855 areestimated to have poured out respectively 17,000,000,000and 38,000,000,000 cubic feet of lava. In 1868 the lavastream forced its way under ground a distance of twentymiles, and burst forth from a fissure two miles long, throwingup enormous columns of crimson lava and red hot rockto the height of five or six hundred feet.

On the eastern part of Mauna Loa, 16 miles from the summitcrater, is Kilauea, the largest continuously active craterin the world. It is eight miles in circumference, and 1,000feet deep. Its eruptions are generally independent of thoseof Mauna Loa.

NEW AIR ENGINE.

A valuable improvement in compressed air engines has recentlybeen patented in this country and in Europe by Col.F. E. B. Beaumont, of the Royal Engineers, and we learnfrom accounts given in the London and provincial papersthat it has proved highly efficient and satisfactory.

The engine possesses some peculiar features which renderit very economical in the use of compressed air. It has twocylinders, one being much larger than the other. Into thesmaller of these cylinders the compressed air is taken directlyfrom the reservoir, and after doing its work there it is dischargedinto the larger cylinder, where it is further expanded,being finally discharged into the open air.

The admission of air to the smaller cylinder is regulated byan adjustable cut-off apparatus, which admits of maintaininga uniform power under a variable pressure. When thereservoir at first starting contains air at a very high pressure,the cut-off is adjusted so that the small cylinder receivesa very small charge of air at each stroke; when thepressure in the reservoir diminishes the cut-off is delayed sothat a larger quantity of air is admitted to the small cylinder;and when the pressure in the reservoir is so far reducedthat the pressure on the smaller piston gives very littlepower, the supply passages are kept open so that the air actsdirectly on the piston of the larger cylinder. This arrangementis also available when the air pressure is high andgreat power is required for a short time, as, for example, instarting a locomotive.

It is, perhaps, needless to mention the advantages a motorof this kind possesses over the steam locomotive. The absenceof smoke and noise renders it particularly desirable fortunnels, elevated roads, and, in fact, for any city railroad.

Further information in regard to this important inventionmay be obtained by addressing Mr. R. Ten Broeck, at theWindsor Hotel, New York.

Telegraph Wires Underground.

Philadelphia newspapers report that the American UnionTelegraph Company are about to try in that city the experimentof putting their wires underground. The plan workswell enough in European cities, and there would seem to beno reason why it should not succeed here, save the indispositionof the companies to bear the first cost of making thechange. For some months the Western Union TelegraphCompany has had the matter under consideration, but willprobably wait until pressed by a rival company before it undertakesthe more serious task of taking down its forest ofpoles and sinking the wires which contribute so much to theprevailing ugliness of our streets. Sooner or later the polesand wires must come down; and it is altogether probablethat the change will be beneficial to the companies in thelong run, owing to the smaller cost of maintaining a subterraneansystem. It will certainly be an advantage to the community.

IMPROVED SAFETY NUT.

That a safety nut so simple and so obviously efficient asthe one shown in the annexed engraving should be amongthe recent inventions in this line instead of being among thefirst, is a curious example of the manner in which inventorsoften overlook the simplest means of accomplishing an end.The principle on which this nut operates will be understoodby reference to the engraving. Two nuts are representedon each bolt, simply for the purpose of showing thedifference between the nut when loose and when screweddown. In practice only one nut is required to each bolt.

The square nut shown in Fig. 1 is concaved on its underside, so that it touches its bearings only at the corners andin the outer face of the nut there are two slots at right anglesto each other. When this nut is screwed home theouter portion is contracted so as to clamp the bolt tightly.

The hexagonal nut shown in Fig. 2 has but a single transverseslot, and the nut is made concave on the under surface,so that when the nut is screwed home it will contractthe outer portion and so clamp the bolt.

This nut may be removed and replaced by means of thewrench, but it will not become accidentally loosened, andthe bolt to which it is applied will always remain tight, asthe nut possesses a certain amount of elasticity. The actionof this nut is such as to prevent stripping the threads ofeither bolt or nut.

As only one nut is used with each bolt, and as no washeror other extra appliance is required, it is obvious that agreat saving is effected by this invention.

We are informed that several of the leading railroads haveadopted this nut, and use it on the tracks, engines, cars, andmachinery. The Atwood Safety Nut Company manufacturethis article in a variety of forms.

Further information may be obtained by addressing J. W.Labaree, Secretary and Treasurer, Room 2, Agawam BankBuilding, Springfield, Mass.

Petroleum Prospects.

The total oil production of the Pennsylvania oil regionsfor the month of October was 2,094,608 barrels. The conditionsin the producing field are gradually giving warrantfor permanently higher prices of crude. The confidence ofthe trade is daily becoming more fixed in the definitenessand limit of the Bradford field, as the last of the several"rich streaks" in the region are being worked.

We entertain an increased belief that the coming year willexhibit a continued falling off in the volume of production,notwithstanding all the modern improvements in drillingand the great energy with which they are employed.

For the past few weeks the markets of both crude and refinedseem to have been rigorously and artificially held bythe refining interest. The refined has been quoted at 12 cts.for four weeks without change—and as a consequence theexporter has taken oil very sparingly. The exports of lastyear to November 1, as compared with the exports of thisyear to November 1, show a decrease of 1,269,646 barrels incrude equivalent. The falling off of production, taken togetherwith the increased demand which must result fromthe present reluctance of exporters, unite in warranting usin the belief above expressed, in enhanced prices for thecoming year.

Our figures show a decrease in production for last month,compared with the preceding month, of 933 barrels per day,notwithstanding the number of wells drilled was slightlygreater than in the preceding month. It will be noticed,too, that the average per well of the new wells for lastmonth is a little less than that of the new wells for themonth before, besides, it is generally recognized that theforce of the gas in the region is gradually becoming less,and pumping is more commonly resorted to. As nearly aswe can ascertain, about one-eighth of all the wheels of theBradford region are now pumping. We believe, however,on the whole, judging the character of the Bradford producingfield, that the falling off of production will be quitegradual. Our reason for this is that the Bradford field isessentially different from its predecessor—the Butler field.The wells in the Butler field were often close together,many of them were very large and fell off rapidly; whilethe wells of the Bradford region are smaller, farther apart,much greater in number, have a greater area from which todraw oil, and consequently decline very much more slowly.—Stowell's Reporter.

TOOL FOR DRIVING AND CLINCHING NAILS.

A novel method of making a nail hole and driving andclinching the nail is shown in the annexed engraving. Theinstrument for making the hole has a notched end whichleaves a ridge in the center of the hole at the bottom. Thenail driving tool consists of a socket provided with a suitablehandle, and containing a follower which rests upon thehead of the nail to be driven, and receives the blows of thehammer in the operation of driving the nail. The nail issplit for one half its length, and the two arms thus formedare slightly separated at the point, so that when they meetthe ridge at the bottom of the hole they will be still furtherseparated and will clinch in the body of the wood.

AUTOMATIC BALANCE ATTACHMENT FOR VALVES.

It is well known that in all air compressors and waterpumps the pressure in cylinder of air compressors or inworking barrel or cylinder of pumps is much greater at thepoint of opening the delivery valves than the actual pressurein the air receivers of compressors or in water column ofpumps because of the difference in area between the topand bottom of delivery valves. In some air compressors ahundred and twenty-five pounds pressure to the square inchis required in the cylinder to eighty pounds in the receiver,and in some instances a hundred pounds pressure is requiredin the cylinder to eighty pounds pressure in the receiver orcolumn.

The engraving shows an invention designed to remedythis defect in air compressors and pumps, to provide a devicewhich will enable the compressors and pumps to operatewith equal pressure on both sides of the delivery valve.

The invention consists of an auxiliary valve arranged outsideof the cylinder, where it is not subjected to back pressure,and connected with the delivery valve by a hollow valvestem.

In the engraving, which is a sectional view, the cylinder ofan air compressor is represented, on the end of which thereis a ring containing delivery ports, through which the airfrom the cylinder is forced into a receiver or conductingpipe. This ring is provided with an inner flange or valveseat on which rests the delivery valve. These parts aresimilar to those seen in some of the air compressors incommon use, and with this construction and arrangementone hundred pounds pressure to the square inch in thecylinder is required to open the valve against eighty poundspressure in the receiver or in the conducting pipes.

A drum having an open end is connected with the cylinderhead by inclined standards, and contains a piston connectedwith the valve by means of a rod that extends centrallythrough the cylinder head. On the outer end of thisrod is screwed an adjusting nut, by means of which thepiston may be adjusted. This rod is bored longitudinally,establishing communication between the compressor cylinderand the drum containing the piston.

It will be seen that the upper face of the piston is exposedso as to be subjected to atmospheric pressureonly, and when the compressor is in operation a portionof the air in the compressor cylinder passes throughthe hollow rod into the space beneath the piston, and thereexerts sufficient pressure, in combination with the pressureon the inner face of the valve, to open the valve against anequal pressure in the receiver or conducting pipes, so thatwhen the pressure in the cylinder equals the pressurein the receivers the valve is opened and held in placeuntil the piston in the cylinder starts on the return stroke,when the pressure under the piston is immediately relievedthrough the hollow rod and the main valve closes.

The space between the valve and its seat is made as shallowas possible, so that the space may be quickly filled andexhausted. The piston may be adjusted to regulate thisspace. This invention was recently patented by Messrs.Samuel B. Connor and Henry Dods, of Virginia City, Nevada.

IMPROVED SAFETY VALVE.

In the annexed cut we have represented a steam safetyvalve, which is the invention of M. Schmidt, M. E., ofZurich, Switzerland. It consists of a lever terminating intwo prongs, one of which extends downward and rests uponthe cap, closing the top of the tube through which the steamescapes. The other prong extends upward and catches undera projection of the steam tube, and forms the fulcrum for thelever. The opposite end of this lever is provided with anadjustable screw pressing upon a plate that rests on the topof a spiral spring, which keeps the valve closed by pressingthe outer end of the lever upward. As soon as the pressureof the steam overcomes the pressure of the spiral spring thevalve will be raised, permitting the steam to escape. Theapparatus is contained in a case having a central aperturefor the escape of steam.

Raising Sunken Vessels.

An experiment recently took place in the East India DockBasin, Blackwall, London, by permission of Mr. J. L. duPlat Taylor, the secretary of the Dock Company, for thepurpose of testing and illustrating the mode of raising sunkenships by means of the apparatus patented by Mr. WilliamAtkinson, naval engineer, of Sheffield. The machinery employedconsists of the necessary number and size, accordingto the power required, of oval or egg-shaped buoys constructedof sheet iron, having an internal valve of a simpleand effective character. Captain Hales Dutton, the dockmaster, who assisted during the operations, had placed hissmall yacht at the inventor's service for the occasion. Thevessel was moored in the basin, and a set of four buoys wereattached to it, one on each side near the bow and the stern.Air was supplied from a pump on the quay by a pipe communicatingwith a small copper globe resting on the deck ofthe vessel, and from which place proceeded four other flexibletubes, one to each buoy, thus distributing the air to eachone equally. The vessel being flooded and in a sinking condition,the buoys were attached and the valves opened; theyrapidly filled with water, and the vessel immediately sankin about 30 feet. Upon the first attempt an air chamber inthe stern had been lost sight of, causing the vessel to comeup to the surface stern uppermost; this being rectified, thevessel was again sent to the bottom, and allowed to remaina short time to allow her to settle down. When the orderwas given to work the pump, the vessel was brought to thesurface, perfectly level, in about three minutes. The apparatusused, although only models, and on a comparativelydiminutive scale (the buoys measuring 3 feet 4 inches inheight and 2 feet 6 inches in diameter), was estimated to becapable of lifting a weight of nearly 20 tons, and that itneeded, as represented by the patentee, only a correspondingincrease in the lifting power to deal successfully withvessels of any tonnage.

NEW HAND POWER BAND SAW.

The engraving shows a new hand power band saw madeby Frank & Co., of Buffalo, N. Y., and designed to be usedin shops where there is no power and where a larger machinewould be useless. It is calculated to meet the wants of alarge class of mechanics, including carpenters and builders,cabinet makers, and wagon makers. It is capable of sawingstuff six inches thick, and has a clear space of thirty inchesbetween the saw and the frame. The upper wheel is adjustedby a screw pressing against a rubber spring whichcompensates for the expansion and contraction of the saw.

The machine has a very complete device for raising, lowering,and adjusting the wheel, and all of theparts are made with a view to obtaining the bestresults in the simplest and most desirable way.

The machine is six feet wide and five feethigh, and weighs 380 lb. The wheels are coveredwith pure rubber bands well cemented.

Further particulars may be obtained by addressingMessrs. Frank & Co., 176 Terrace street,Buffalo, N. Y.

The Harbor of Montreal.

A plan for the improvement of the harbor ofMontreal, Canada, has been submitted to theCity Board of Trade by James Shearer, a wellknown citizen. Mr. Shearer's plan is to divertthe current of the St. Lawrence opposite the cityinto the channels between St. Helen's Island andthe southern shore, and by having various obstructionsremoved from the channel, and runninga dam, or "peninsula," as he calls it, builtfrom Point St. Charles, in the west end of thecity, to St. Helen's Island, midway in the river,thus stopping the current from running throughthe present main channel between the city andSt. Helen's Island.

Among the practical advantages that will accrueto the city and harbor from the carryingout of this project, Mr. Shearer sets forth thefollowing: The dam will prevent the shoring of ice oppositethe city, and the consequent flooding of the Griffintown district,which is annually very destructive to property, andwill make a still harbor, where vessels may lie during thewinter. It is estimated that the construction of the dam,which would be 2,700 feet long and 900 feet broad, wouldraise the water two feet in the river and lower it ten feet inthe harbor. This would give a head of twenty-five feet formills, elevators, and factories, and the transportation offreight. The dam would afford a roadway across the river,upon the construction of a bridge from St. Helen's Islandto St. Lambert, thus removing the necessity of a tunnel.The roadway could be utilized for a railway, a road for carriagesand foot passengers. The estimated cost of the improvementis $7,000,000.

APPARATUS FOR REMOVING ICE FROM RAILROADS.

The engraving shows an improved apparatus for removingsnow and ice from railroads and streets by means ofheat. The invention consists of a double furnace mountedon wheels, which are incased in the fire boxes of the furnace,so that in use the entire apparatus, including thewheels, will become highly heated, so that the snow and icewill not only be melted by radiant heat, but by the actualcontact of the hot surfaces of the furnace and wheels. Thisapparatus was recently patented by the late E. H. Angamar,of New Orleans, La.

Ericsson's New Submarine Gun.

The protracted trials conducted on board the Destroyer totest its submarine gun terminated last week. Having, saystheArmy and Navy Journal, in a previous issue describedthis novel type of naval artillery, it will suffice to remindour readers that its caliber is 16 inches, length of bore 30feet, and that it is placed at the bottom of the vessel, themuzzle passing through an opening formed in the wroughtiron stem.

We have hitherto, in discussing the properties of the Destroyer,referred to its offensive weapon as a "torpedo," aterm not altogether inappropriate while it was actuated bycompressed air. But Capt. Ericsson having in the meantimewholly abolished compressed air in his new system of navalattack, substituting guns and gunpowder as the means ofproducing motive energy, it will be proper to adopt the constructor'sterm,projectile. It will not surprise those who areacquainted with the laws of hydrostatics and the enormousresistance offered to bodies moving swiftly through water,that the determination of the proper form of projectile forthe submarine gun has demanded protracted experiments,commencing at the beginning of June and continued up tolast week, as before stated. The greater portion of these experiments,it should be observed, has been carried out witha gun 30 feet long, 15 inches caliber—not a breech-loader,however, as in the Destroyer, but a muzzle-loader, suspendedunder the bottom of two wrecking scows, the gun beinglifted above the water, after each shot, by shears and suitabletackle. The present projectile of the Destroyer is theresult of the extended trials referred to; its length is 25 feet6 inches, diameter 16 inches, and its weight 1,500 pounds,including 250 pounds of explosive materials. We are not atliberty at present to describe its form, but we may mentionthat the great length of the body and the absence of all internalmachinery enable the constructor to carry the statedenormous quantity of explosive matter. With minimumcharge of powder in the chamber of the gun, the speed attainedby the projectile reaches 310 feet in the first three seconds.

The question may be asked, in view of these facts, whetherthe boasted costly steam ram is not superseded by the cheapaggressive system represented by the Destroyer. Evidentlythe most powerful of the English steam rams could not destroyan armored ship as effectually as the projectile fromthe submarine gun, the explosion of which is capable of shatteringany naval structure.

It should be borne in mind, also, that being protected byheavy inclined transverse armor, the Destroyer, attackingbows on, can defy ordnance of all calibers. Again, the carrierof the submarine gun, in addition to the swiftness of itsprojectile, can outrun ironclad ships.

RECENT INVENTIONS.

Mr. Francis M. Osborn, of Port Chester, N. Y., haspatented a covering for a horse that protects him from theweather and from chafing. The blanket has a band, alsostays and straps, the use of which does away with the surcingleand affords a most efficient protection for the horse,and may be easily worn under harness in wet weather or atother times, when desirable.

A novel device, designed especially for containing boxes ofcigars and protecting and displaying their contents, has beenpatented by Mr. Robert B. Dando, of Alta, Iowa. The inventionconsists of a case containing shelves, on which arefixed the covered cigar or other boxes, cords connecting thebox lids and case doors, so that the opening of the case doorscauses the box lids to open.

An improved bottle stopper has been patented by Mr.Andrew Walker, of Cincinnati, O. The invention consistsin combining with the stopper caps connected by an intermediatespring.

Mr. James B. Law, of Darlington Court House, S. C.,has patented an improved construction of buckle for fasteningthe ends of cotton and other bale bands; it consists ina buckle having a permanent seat for one end of the baleband, a central opening, into which the other end of theband is entered through an oblique channel, and a bar offsettingfrom the plane of the buckle, notched or recessed toprevent lateral movement of the band, and connecting thefree ends of the buckle on each side of the oblique channelto strengthen the buckle.

An improved buckboard wagon has been patented by Mr.William Sanford, of Cohoes, N. Y. The invention consistsin combining with the buckboards curved longitudinalsprings placed beneath the buckboards, and curved crosssprings connected at their ends with the buckboards by capplates so as to increase the strength and elasticity of thewagon.

An improved vehicle wheel has been patented by Messrs.George W. Dudley and William J. Jones, of Waynesborough,Va. The main object of this invention is to form awheel hub for vehicles in such manner that thewheel will yield sufficiently when undue andsudden strains or jars may come upon it to receivethe force of the blow and shield the otherportions of the vehicle from the destructiveeffects of such action, as well as to afford easeand comfort of motion to the occupant; and theimprovement consists in securing the inner endsof the spokes to rim plates, to form a fixed andsolid connection therewith, the rim plates beingloosely secured to the butt flanges and box ofthe hub, so that it is free to move in a verticalplane, but prevented from moving laterally andlimited in its vertical movement by an elasticpacking interposed between the inner ends ofthe spokes and the hub box.

Mr. Francis G. Powers, of Moweaqua, Ill.,has patented an improvement in the class of atmosphericclothes pounders, that is to say,pounders which are constructed with one ormore chambers or cavities in which the air isalternately compressed and allowed to expandat each reciprocation.

An improved means for connecting the bodyof a baby carriage to the running gear has beenpatented by Mr. Charles M. Hubbard, of Columbus,Ohio. It consists in supporting the rearend by one or more coil springs, and hingingthe front portion of the body to a pair of upturned supportsrising from the front axle.

An improved ferrule for awl handles has been patented byMr. Jules Steinmeyer, of St. Louis, Mo. The object of thisinvention is to prevent splitting of the handle, to secure boththe ferrule and leather pad firmly in place, and to furnisha durable and serviceable awl handle.

NEW TELEGRAPH INSULATOR.

The insulator represented in the annexed engraving wasoriginally designed to meet the requirements of South Americantelegraph service, but it is equally well adapted tolines in other places. The main idea is to avoid breakagefrom expansion and contraction in a climate subject to suddenchanges of temperature, and to avoid the mischief occasionedby a well known South American bird, the "hornero,"by building nests of mud on the brackets and insulators.With this insulator these nests cannot cause a weathercontact or earth; on the contrary, the nest rather improvesthe insulation. The sectional view, Fig 2, shows the constructionof the insulator and the manner of fastening it tothe cross arm or bracket. A rubber ring is placed betweenthe upper end of the porcelain insulator and the cross arm,and another similar ring is placed between the head of thesuspending screw and the bottom of the insulator. It willbe noticed that with this construction the insulator cannotbe broken by the contraction of the screw or by the swellingof the cross-piece. This insulator can be used on an ironbracket and in connection with either iron or wooden posts,and is in every way more secure than the insulators in commonuse. The first cost of these insulators compares favorablywith the cheapest in market, while it is less liable tobreakage, lasts longer, and gives better results. It has beenpatented in this country and in Europe.

Further information maybe obtained by addressing Mr. J.H. Bloomfield, Concordia, Entre Reos, Argentine Republic,South America.

BUSINESS COLLEGES.

PACKARD'S BUSINESS COLLEGE.

There are two very general prejudices against the class ofschools known as business colleges. One is that their chiefaim—next to lining the pockets of their proprietors—is toturn out candidates for petty clerkships, when the countryis already overrun with young men whose main ambition isto stand at a desk and "keep books." The other is that thepractical outcome of these institutions is a swarm of conceitedflourishers with the pen, who, because they have copied aset or two of model account books and learned to imitatemore or less cleverly certain illegibly artistic writing copies,imagine themselves competent for any business post, andworthy of a much higher salary than any merely practicalaccountant who has never been to a business college or attemptedthe art of fancy penmanship as exhibited in spreadeagles and impossible swans.

As a rule popular prejudices are not wholly unfounded inreason; and we should not feel disposed to make an exceptionin this case. When the demand arose for a more practicalschooling than the old fashioned schools afforded, noend of writing masters, utterly ignorant of actual businesslife and methods, hastened to set up ill managed writingschools which they dubbed "business colleges," and bydint of advertising succeeded in calling in a multitude of aspirantsfor clerkships. In view of the speedy discomfitureof the deluded graduates of such schools when brought faceto face with actual business affairs, and the disgust of theiremployers who had engaged them on the strength of theiralleged business training, one is not so much surprised thatprejudice against business colleges still prevails in manyquarters, as that the relatively few genuineinstitutions should have been ableto gain any creditable footing at all.

The single fact that they have overcomethe opprobrium cast upon theirname by quacks, so far as to maintainthemselves in useful prosperity, winninga permanent and honorable placeamong the progressive educational institutionsof the day, is proof enoughthat they have a mission to fulfill andare fulfilling it. This, however, is notsimply, as many suppose, in trainingyoung men and young women to beskilled accountants—a calling of nomean scope and importance in itself—butmore particularly in furnishingyoung people, destined for all sorts ofcallings, with that practical knowledgeof business affairs which every man orwoman of means has constant need ofin every-day life. Thus the true businesscollege performs a twofold function.As a technical school it trainsits students for a specific occupation,that of the accountant; at the sametime it supplements the education notonly of the intending merchant, butequally of the mechanic, the man ofleisure, the manufacturer, the farmer,the professional man—in short, of any one who expects to mixwith or play any considerable part in the affairs of men. Themechanic who aspires to be the master of a successful shopof his own, or foreman or manager in the factory of another,will have constant need of the business habits and the knowledgeof business methods and operations which a properlyconducted business school will give him. The same is trueof the manufacturer, whose complicated, and it may be extensive,business relations with the producers and dealerswho supply him with raw material, with the workmen whoconvert such material into finished wares, with the merchantsor agents who market the products of his factory, all requirehis oversight and direction. Indeed, whoever aspires tosomething better than a hand-to-mouth struggle with poverty,whether as mechanic, farmer, professional man, orwhat not, must of necessity be to some degree a businessman; and in every position in life business training and apractical knowledge of financial affairs are potent factors insecuring success.

How different, for example, would have been the historyof our great inventors had they all possessed that knowledgeof business affairs which would have enabled them to puttheir inventions in a business like way before the world, orbefore the capitalists whose assistance they wished to invoke.The history of invention is full of illustrations of men whohave starved with valuable patents standing in their names—patentswhich have proved the basis of large fortunes tothose who were competent to develop the wealth that wasin them. How often, too, do we see capable and ingeniousand skillful mechanics confined through life to a small shop,or to a subordinate position in a large shop, solely throughtheir inability to manage the affairs of a larger business. Onthe other hand, it is no uncommon thing to see what mightbe a profitable business—which has been fairly thrust upona lucky inventor or manufacturer by the urgency of popularneeds—fail disastrously through ignorance of businessmethods and inability to conduct properly the larger affairswhich fell to the owner's hand.

Of course a business training is not the only condition ofsuccess in life. Many have it and fail; others begin withoutit and succeed, gaining a working knowledge of business affairsthrough the exigencies of their own increasing businessneeds. Nevertheless, in whatever line in life a man's coursemay fall, a practical business training will be no hinderanceto him, while the lack of it may be a serious hinderance. Theschool of experience is by no means to be despised. Tomany it is the only school available. But unhappily itsteachings are apt to come too late, and often they are fatallyexpensive. Whoever can attain the needed knowledge in aquicker and cheaper way will obviously do well so to obtainit; and the supplying of such practical knowledge, and thetraining which may largely take the place of experience inactual business, is the proper function of the true businesscollege.

Our purpose in this writing, however, was not so much toenlarge upon the utility of business colleges, properly socalled, as to describe the practical working of a representativeinstitution, choosing for the purpose Packard's BusinessCollege in this city.

This school was established in 1858, under the name ofBryant, Stratton & Packard's Mercantile College, by Mr. S.S. Packard, the present proprietor. It formed the NewYork link in the chain of institutions known as the Bryant& Stratton chain of business colleges, which ultimatelyembraced fifty co working schools in the principal cities ofthe United States and Canada. In 1867 Mr. Packard purchasedthe Bryant & Stratton interest in the New York College,and changed its name to Packard's Business College,retaining the good will and all the co operative advantagesof the Bryant & Stratton association. The original purposeof the college, as its name implies, was the education of youngmen for business pursuits. The experience of over twentyyears has led to many improvements in the working of theschool, and to a considerable enlargement of its scope andconstituency, which now includes adults as well as boys,especial opportunities being offered to mature men whowant particular instruction in arithmetic, bookkeeping,penmanship, correspondence, and the like.

The teachers employed in the college are chosen for theirpractical as well as their theoretical knowledge of businessaffairs, and every effort is made to secure timeliness and accuracyin their teachings. Constant intercourse is kept upwith the departments at Washington as to facts and changesin financial matters, and also with prominent businesshouses in this and other cities. Among the recent lettersreceived in correspondence of this sort are letters from theSecretary of State of every State in the Union with regardto rates of interest and usury laws, and letters fromeach of our city banks as to methods of reckoning time onpaper, the basis of interest calculations, the practices concerningdeposit balances, and other business matters subjectto change. The aim of the proprietor is to keep theschool abreast of the demands of the business world, and toomit nothing, either in his methods or their enforcement,necessary to carry out his purpose honestly and completely.An idea of the superior housing of the college will be obtainedfrom the views of half a dozen of the rooms at No805 Broadway, as shown in this issue of theScientificAmerican—the finest, largest, most compact, and convenientsuite of rooms anywhere used for this purpose.

The college is open for students ten months of the year,five days each week, from half past nine in the morninguntil half past two in the afternoon. Students can enter atany time with equal advantage, the instruction being for themost part individual. The course of study can be completedin about a year. The proprietor holds that with thisamount of study a boy of seventeen should be able—

1. To take a position as assistant bookkeeper in almostany kind of business; 2. To do the ordinary correspondenceof a business house, so far as good writing, correct spelling,grammatical construction, and mechanical requisites areconcerned; 3. To do the work of an entry clerk or cashier;4. To place himself in the direct line of promotion to anydesirable place in business or life, with the certainty of holdinghis own at every step.

In this the student will have the advantage over the uneducatedclerk of the same age and equal worth andcapacity, in that he will understand more or less practicallyas well as theoretically the duties of those above him, andwill thus be able to advance to more responsible positionsas rapidly as his years and maturity may justify. It is obviousthat the knowledge which makes an expert accountantwill in all probability suffice for the general businessrequirements of professional men, the inheritors of propertyand business, manufacturers, mechanics, and othersto whom bookkeeping and other business arts are usefulaids, but not the basis of a trade. For the last-namedclasses, and for women, shorter periods of study are provided,and may be made productive of good results.

A sufficient idea of the general working of the college maybe obtained by following a student through the several departments.After the preliminary examination a student whois to take the regular course of study enters the initiatoryroom. Here he begins with the rudiments of bookkeeping,the study which marks his gradation. The time not givento the practice of writing, and to recitations in other subjects,is devoted to the study of accounts. He is required,first, to write up in "skeleton" form—that is, to place thedates and amounts of the several transactions under theproper ledger titles—six separate sets of books, or the recordof six different business ventures, wherein are exhibitedas great a variety of operations as possible, withvarying results of gains and losses, and the adjustmentthereof in the partners' accounts, or in the account of thesole proprietor. After getting the results in this informalway—which is done in order as quickly as possible to getthe theory of bookkeeping impressedupon his mind—he is required to goover the work again carefully, writingup with neatness and precision all theprincipal and auxiliary books, with thedocuments which should accompanythe transactions, such as notes, drafts,checks, receipts, invoices, letters, etc.The work in this department will occupyan industrious and intelligentstudent from four to six weeks, dependingupon his quickness of perceptionand his working qualities.While progressing in his bookkeeping,he is pursuing the collateral studies,a certain attainment in which is essentialto promotion, especially correctingany marked deficiency in spelling, arithmetic,and the use of language.

Upon a satisfactory examination thestudent now passes to the second department,where a wider scope ofknowledge in accounts is opened tohim, with a large amount of practicaldetail familiarizing him with the actualoperations of business. The greatestcare is taken to prevent mere copyingand to throw the student upon his ownresources, by obliging him to correcthis own blunders, and to workout his own results; accepting nothing as final that hasnot the characteristics of real business. Much care is bestowedin this department upon the form and essentialmatter of business paper, and especially of correspondence.A great variety of letters is required to be writtenon assigned topics and in connection with the businesswhich is recorded, and thorough instruction is given inthe law of negotiable paper, contracts, etc. During allthis time the student devotes from half an hour to anhour daily to penmanship, a plain, practical, legible handbeing aimed at, to the exclusion of superfluous lines andflourishes. It is expected that the work in the first andsecond departments will establish the student in the mainprinciples of bookkeeping, in its general theories, and theirapplication to ordinary transactions.

In the third department the student takes an advancedposition, and is expected, during the two or three monthshe will remain in this department, to perfect himself in themore subtle questions involved in accounts, as well as toshake off the crude belongings of schoolboy work. He willbe required to use his mind in everything he does—to dependas much as possible upon himself. The work whichhe presents for approval here must have the characteristicsof business. His letters, statements, and papers of all kindsare critically examined, and approved only when givingevidence of conscientious work, as well as coming up tostrict business requirements. Before he leaves this departmenthe should be versed in all the theories of accounts,should write an acceptable business hand; should be able toexecute a faultless letter so far as relates to form, spelling,and grammatical construction, should have a fair knowledgeof commercial law, and have completed his arithmeticalcourse.

The next step is to reduce the student's theoretical knowledgeto practice, in a department devoted to actual businessoperations. This business or finishing department isshown at the upper left corner of our front page illustration.The work in this department is as exacting and asreal as the work in the best business houses and banks. Atthe extreme end of the room is a bank in complete operation,as perfect in its functions as any bank in this city orelsewhere. The records made in its books come from the[Pg 389]real transactions of dealers who are engaged in different linesof business at their desks and in the offices. The smalloffice adjoining the bank, on the right, is a post office, theonly one in the country, perhaps, where true civil servicerules are strictly observed. In connection with it is a transportationoffice. From fifty to a hundred letters daily arereceived and delivered by the post office, written by or tothe students of this department.

The correspondence thus indicated goes on not only betweenthe students of this college, but between members ofthis and other similar institutions in different parts of thecountry. A perfected system of intercommunication has foryears been in practice between co-ordinate schools in NewYork, Boston, Brooklyn, Philadelphia, Chicago, Baltimore,and other cities, by which is carried on an elaborate schemeof interchangeable business, little less real in its operationsand results than the more tangible and obtrusive activitywhich the world recognizes as business.

The work of the transportation office corresponds withthat of the post office in its simulation of reality. The allegedarticles handled are represented by packages bearingall the characteristic marks of freight and express packages.They are sent by mail to the transportation company, andby this agency delivered to the proper parties, from whomthe charges are collected in due form, and the requisitevouchers passed. Whatever is necessary in the way of manipulationto secure the record on either hand is done, and,so far as the clerical duties are concerned, there is no differencebetween handling pieces of paper which represent merchandiseand handling the real article.

In the bank is employed a regular working force, such asmay be found in any bank, consisting of a collector or runner,a discount clerk, a deposit bookkeeper, a general bookkeeper,and a cashier. The books are of the regular form,and the work is divided as in most banks of medium size,and the business that is presented differs in no importantparticular from that which comes to ordinary banks. Aftergetting a fair knowledge of theory, the student is placed inthis bank. He begins in the lowest place, and works upgradually to the highest, remaining long enough in eachposition to acquaint himself with its duties. He is madefamiliar with the form and purpose of all kinds of businesspaper, and the rules which govern a bank's dealings with itscustomers. He gets a practical knowledge of the law ofindorsement and of negotiability generally, and is calledupon to decide important questions which arise between thebank and its dealers. Wherever he finds himself at fault hehas access to a teacher whose duty it is to give the informationfor which he asks, and who is competent to do it.

Throughout the whole of this course of study and practicethe students are treated like men and are expected tobehave like men.

The college thus becomes a self-regulating community, inwhich the students learn not only to govern themselves, butto direct and control others. As one is advanced in positionhis responsibilities are increased. He is first a merchant oragent, directing his own work; next, a sub-manager, andfinally manager in a general office or the bank, with clerkssubject to his direction and criticism, until he arrives at theexalted position of "superintendent of offices," whichgives him virtual control of the department. This is, infact, an important part of his training, and the reasonableeffect of the system is that the student, being subject toorders from those above him, and remembering that he willshortly require a like consideration from those below him,concludes that he cannot do a better thing for his own futurecomfort than to set a wholesome example of subordination.

This, however, is not the only element of personal disciplinethat the college affords. At every step the student'sconduct, character, and progress are noted, recorded, andsecurely kept for the teacher's inspection, as well as that ofhis parents and himself. Such records are kept in the budgetroom, shown in the lower left corner of the front page.

This budget system was suggested by the difficulties encounteredin explaining to parents the progress and standingof their sons. The inconvenience of summoning teachers,and of taking students from their work, made necessarysome simpler and more effective plan. The first thing requiredof a new student is that he should give some accountof himself, and to submit to such examinations and tests aswill acquaint his teachers with his status. This account andthese tests constitute the subject-matter of his first budget,which is placed at the bottom of his box, and every fourweeks thereafter, while he remains in the school, he is requiredto present the results of his work, such as his writtenexaminations in the various studies, his test examples inarithmetic, his French, German, and Spanish translationsand exercises, various letters and forms, with four weeklyspecimens of improvement in writing, the whole to be formallysubmitted to the principal in an accompanying letter;the letter itself to exhibit what can be thus shown of improvementin writing, expression, and general knowledge.These budgets, accumulating month by month, are made tocover as much as possible of the student's school work, andto constitute the visible steps of his progress.

Besides this is a character record, kept in a small book assignedto each student, every student having free access tohis own record, but not to that of any fellow student. Eachbook contains the record of a student's deportment from thefirst to the last day of his attendance, with such commentsand recommendations as his several teachers may thinklikely to be of encouragement or caution to him.

In addition to the strictly technical training furnished bythe college, there is given also not a little collateral instructioncalculated to be of practical use to businessmen. For example, after roll call every morning some littletime is spent in exercises designed to cultivate the art of intelligentexpression of ideas. Each day a number of studentsare appointed to report orally, in the assembly room, uponsuch matters or events mentioned in the previous day's newspapersas may strike the speaker as interesting or important.Or the student may describe his personal observation of anyevent, invention, manufacture, or what not; or report uponthe condition, history, or prospects of any art, trade, orbusiness undertaking. This not to teach elocution, but totrain the student to think while standing, and to express himselfin a straightforward, manly way.

Instruction is also given in the languages likely to be requiredin business intercourse or correspondence; in phonography,so far as it may be required for business purposes;commercial law relative to contracts, negotiablepaper, agencies, partnerships, insurance, and other businessproceedings and relations; political economy, and incidentallyany and every topic a knowledge of which may be ofpractical use to business men.

In all this the ultimate end and aim of the instructionoffered are practical workable results. Mr. Packard regardseducation as a tool. If the tool has no edge, is not adaptedto its purpose, is not practically usable, it is worthless as atool. This idea is kept prominent in all the work of thecollege, and its general results justify the position thustaken. The graduates are not turned out as finished businessmen, but as young men well started on the road towardthat end. As Mr. Packard puts it: "Their diplomas donot recommend them as bank cashiers or presidents, or asmanagers of large or small enterprises, but simply as havinga knowledge of the duties of accountantship. They rarelyfail to fulfill reasonable expectations; and they are not responsiblefor unreasonable ones."

American Institute of Architects.

The fourteenth annual convention of the American Instituteof Architects began in Philadelphia, November 17. Mr.Thomas U. Walter, of Philadelphia, presided, and fifty ormore prominent architects were present. In his annual addressthe president spoke of the tendency of the architecturalworld as decidedly in the direction of originality. But littleattention is paid to the types of building drawn from theworks of by-gone ages or to the mannerisms of the more recentpast. Progress in the development of the elements oftaste and beauty, and the concretion of æsthetic principleswith common sense in architectural design, are now everywhereapparent. The responsibilities of architects are greaterthan they have ever before been; the growing demand of thetimes calls for intelligent studies in all that relates to architecture,whether it be in the realm of æsthetics, in sciencesthat relate to construction, in the nature and properties ofthe materials used, in the atmosphere that surrounds us, or inthe availability of the thousand-and-one useful and ingeniousinventions that tend to promote the convenience and completenessof structures.

Papers were read by Mr. A. J. Blood, of New York, on"The Best Method of Solving the Tenement House Problem;"Mr. George T. Mason, Jr., of Newport, on "ThePractice of American Architects during the Colonial Period;"Mr. Robert Briggs, of Philadelphia, on "The Ventilation ofAudience Rooms;" Mr. T. M. Clark, of Boston, on "FrenchBuilding Laws, etc."

The following named officers were elected: President, T. U.Walter, Philadelphia; Treasurer, O. P. Hatfield, NewYork; Secretary, A. J. Blood. Trustees, R. M. Hunt, H. M.Congdon, J. Cady, Napoleon Le Brun, New York. Committeeon Publication, R. M. Upjohn, New York; T. M.Clark, Boston; John McArthur, Jr., Philadelphia; A. J.Blood, H. M. Congdon, New York. Committee on Education,W. R. Narr, Boston; Russell Sturgis, New York; N.Clifford Ricker, Champagne, Ill.; Henry Van Brunt, Boston;Alfred Stone, Providence. Corresponding Secretary,T. M. Clark, Boston.

The time and place of the next annual convention wereleft to the Board of Trustees, with a request that Washingtonbe selected.

Vennor's Winter Predictions.

He communicates as follows to the AlbanyArgus: "Decemberwill, in all probability, open with little snow, butthe weather will be cloudy, threatening snow falls. Duringthe opening days of the month, dust, with the very light mixtureof snow which may have fallen, will be swept influrries by the gusty wind. There will probably be some snowfrom about the 4th of the month. With the second quarterof the month colder weather will probably set in with fallsof snow. The farmers will be able to enjoy sleigh rides inthe cold, exhilarating air, but good sleighing need not be expecteduntil after the middle of the month. There will bea spell of mild weather about the 13th and 14th. After abrief interval of mild weather, during which more snow willfall, the third quarter of the month will probably see blusteringand cold weather—a cold snap with heavy snow stormsand consequent good sleighing. Very cold weather may beexpected during this quarter. The last quarter of the monthwill bring milder weather, but will terminate, probably, withheavy snow-falls and stormy weather; in fact, the heaviestsnow falls will be toward the end of the month, and snowblockades may be looked for, the snow falls extending farto the southward, possibly as far as Washington, with verystormy weather around New York and Boston." Mr. Vennor'slatest predictions are that the coming month will be"decidedly cold, with tremendous snow-falls during the latterhalf and early part of January, causing destructive blockadesto railroads."

The London Underground Railway.

The opening recently of the extension of the MetropolitanRailway to Harrow, and the early commencement of anotherof the lines of the company, give especial prominence to it.The Metropolitan Underground Railway is emphatically thegreat passenger railway of the country, for its few miles ofline carry more than the hundreds of miles of line of companiessuch as the London and North Western or GreatWestern. Seventeen years ago—in 1868—the Metropolitancarried less than 10,000,000 passengers, and in the full year'swork of the following twelve months it carried less than12,000,000. But year by year, almost without exception,the number of passengers has grown. In 1865, over 15,000,000passengers were carried; in 1867, over 23,000,000; andin 1870, over 39,000,000 passengers traveled on the line.The years that have since passed have swollen that number.In 1872, over 44,300,000 were carried, but in the followingyear there was one of the few checks, and not till 1875 wasthe number of 1872 exceeded. In 1875 it rose to 48,302,000;in 1877 it had advanced to 56,175,000; in 1878 to 58,807,000;and in 1879 to 60,747,000. In the present year there has beena further advance, the number carried for the first sixmonths of the present year being 31,592,429. When it isborne in mind that this is equal to 7,272 passengers everyhour, and that the length of line worked by the company'sengines, including that of the "foreign" line worked, isslightly less than 25 miles, the fecundity in traffic of themetropolitan district must be said to be marvelous. It is tobe regretted that the official account from which these figuresare given does not give any idea of the number of passengersin the different classes, for such a return would beof value. It is a marvelous fact in the history of locomotionthat this great passenger traffic is worked with not more than53 engines, while the total number of carriages, 195, is incomparison with the number of travelers in them a marvelin railway history. But it is tolerably clear that there is yeta vast amount of undeveloped metropolitan traffic, and it isalso certain that as that traffic is developed the future of theMetropolitan as it attains more completeness will be brightereven than it has been in the past. The great city is more andmore the mart of the world, and the traffic and travel to andin it must increase. That increase will be shared in considerabledegree by the "underground" companies, and as theyhave shown that their capabilities of traffic are almost boundless,it may be expected that the oldest and the chief of thesewill in the early future know a growth as continuous if lessrapid than in the past.

We take the above from theEngineer, London. In this citythere are now existing 27 miles of elevated steam railways forlocal passenger traffic. These roads have carried during thepast year 61,000,000 of passengers. In this service they employ175 locomotives and 500 passenger cars. It is a terriblenuisance to have these locomotives and cars constantlywhizzing through the public streets; still the roads are agreat accommodation. The only underground railway inthis city is that of the New York Central and Hudson River,4 miles in length, extending under Fourth avenue fromForty-second street to Harlem River. Over this road theenormous traffic of the Central, Harlem, and the New Havenroads, with their connections, passes. But so removed frompublic sight are the cars and locomotives that the existenceof this underground railway is almost forgotten.

Tempering Chisels.

A practical mechanic communicates to theScientificAmerican the following: In hardening and tempering acold chisel care should be taken to have a gradual shadingof temper. If there is a distinct boundary line of tempercolor between the hard cutting edge and softer shank portion,it will be very apt to break at or near that line. Thecutting edge portion of the chisel should be supported by abacking of steel gradually diminishing in hardness; and sowith all metal cutting tools that are subjected to heavystrain. Not every workman becomes uniformly successfulin this direction, for, in addition to dexterity, it requires anice perception of degree of heat and of color in order toobtain the best result.

Mr. A. A. Knudson, of Brooklyn, N. Y., has lately perfectedand patented a system of protecting oil tanks fromlightning, which is approved by several prominent electricians.The invention includes a device for distributing aspray of water over the top of the tank for condensing therising vapor and cooling the tank; a system of lightningconductors connected with a gutter surrounding the tank,and a hollow earth terminal connected with the gutter bya pipe, and designed to moisten the earth, and at the sametime prevent the earth around the terminal from becomingsaturated with oil.

A correspondant of theChristian Union, writing fromConstantinople, says that Abd ul-Hamid, the Sultan ofTurkey, reads theScientific American, the engravingsin which seem to specially interest him. The writer addsthat whatever in literature the Sultan may chance to hearof which he thinks may interest him, he has translated intoTurkish.

AMATEUR MECHANICS.

A SIMPLE SINGLE-ACTING STEAM ENGINE.

The great bugbear staring the amateur mechanic in theface when he contemplates making a small steam engine isthe matter of boring the cylinder. To bore an iron cylinderon a foot lathe is difficult even when the lathe is providedwith automatic feed gear, and it is almost impossible withthe ordinary light lathe possessed by most amateurs. Tobore a brass cylinder is easier, but even this isdifficult, and the cylinder, when done, is unsatisfactoryon account of the difficulty of adaptinga durable piston to it.

The engravings show a simple steam engine,which requires no difficult lathe work; in factthe whole of the work may be done on a veryordinary foot lathe. The engine is necessarilysingle-acting, but it is effective nevertheless, beingabout 1-20 H. P., with suitable steam supply.It is of sufficient size to run a foot lathe, scrollsaw, or two or three sewing machines.

The cylinder and piston are made from mandreldrawn brass tubing, which may be purchasedin any desired quantity in New Yorkcity. The fittings are mostly of brass, that beingan easy metal to work.

Shaft.—Diameter, 5/8 in.; diameter of bearings, 1/2 in.;length. 6 in.; distance from bed to center of shaft, 1-1/2 in.

Valve.—Diameter of chamber, 9-16 in.; length, 1-1/4 in.;width of valve face working over supply port, 3/32 in.;width of space under valve, 3/8 in.; length of the same, 1 in.;distance from center of valve spindle to center of eccentricrod pin, 3/4 in.

Ports, supply—Width, 1/16 inch.; length, 1 in. Exhaust.—Width,1/8 in.; length, 1 in.; space between ports, 5-16 in.

Eccentric.—Stroke, 3/4 in.; diameter, 1-5/16 in.length of eccentric rod between centers, 8-3/8 in.

Diameter of vertical posts, 9-16 in.; distance apart, 3-1/2in.; length between shoulders 6-1/4 in.

The connecting rod, eccentric rod, crank pin, and shaft,are of steel. The eccentric-strap and flywheel are cast iron,and the other portions of the engine are of brass. Thescrew threads are all chased, and the flange,a, and head ofthe piston, F, in addition to being screwed, are further securedby soft solder.

Fig. 1 shows the engine in perspective. Fig 2 is a sideelevation, with parts broken away. Fig. 3 is a verticaltransverse section. Fig. 4 is a partial plan view. Fig.5 is a detail view of the upper end of the connecting rodand its connections; and Fig.6 is a horizontal section takenthrough the middle of thevalve chamber.

The cylinder, A, is threadedexternally for 1 inch fromits lower end, and the collar,a, 1/4 inch thick, is screwedon and soldered. The faceof the collar is afterwardturned true. The samethread answers for the nutwhich clamps the cylinder inthe plate, B, and for thegland,b, of the stuffing box,which screws over the beveledend of the cylinder, andcontains fibrous packing filledwith asbestos or graphite.The posts, C, are shoulderedat the ends and secured intheir places by nuts. Theirbearing surface on the plate,D, is increased by the additionof a collar screwed on.The posts are made fromdrawn rods of brass, andneed no turning except at theends.

The cylinder head, E,which is a casting containingthe valve chamber, is screwedin. The piston, F, fits thecylinder closely, but not necessarilysteam tight. Thehead is screwed in and soldered,and the yoke, G, whichreceives the connecting rodpin, is screwed into the head.The connecting rod, H, is ofsteel with brass ends. The lower end, which receives thecrank pin, is split, and provided with a tangent screw fortaking up wear. The crank pin is secured in the crankdisk, I, by a nut on the back. The eccentric rod, J, is ofsteel, screwed at its lower end into an eccentric strap ofcast or wrought iron, which surrounds the eccentric, K.The valve, L, is slotted in the back to receive the valvespindle, by which it is oscillated. The ports are formed bydrilling from the outside, and afterward forming the slot,with a graver or small sharp chisel. The supply port, forconvenience, may be somewhat enlarged below. The holesfor the exhaust port will be drilled through the hole intowhich the exhaust pipe is screwed. The chamber communicatingwith the exhaust is cored out in the casting.

The easiest way to make the valve is to cut it out of asolid cylinder turned to fit the valve chamber.

An engine of this kind will work well under a steam pressureof 50 lb., and it may be run at the rate of 200 to 250revolutions per minute.

It is desirable to construct a flat pasteboard model toverify measurements and to get the proper adjustment ofthe valve before beginning the engine. M.

MISCELLANEOUS INVENTIONS.

An improved finger ring has been patented by Mr. DavidUntermeyer, of New York city. The object of this inventionis to furnish finger rings so constructed thatthey can be opened out to represent serpents,and which, when being worn, will give no indicationof being anything more than rings.

An improved heel skate-fastener has been patentedby Mr. Elijah S. Coon, of Watertown,N.Y. This invention consists, essentially, of ascrew threaded hollow plug or thimble, a dirtplate for covering the opening in the plug, anda spring for holding the dirt plate in place. Thisfastener possesses several advantages over onethat is permanently attached to the heel. Beingcylindrical, it is more easily connected, becausethe hole for its reception can be made with a commonauger or bit without the necessity for lastingthe boot or shoe or using a knife or chisel.Being screw threaded it can be readily screwedinto place with a common screwdriver; this alsoenables it to be screwed either in or out, in orderto make it fit the heel key. The screw threadpermits of screwing it in beyond the surface ofthe heel, so as to prevent it from wearing out bythe ordinary wearing of the shoe.

An improved velocipede has been patented byMessrs. Charles E. Tripler and William H. Roff,of New York city. The object of this inventionis to obtain a more advantageous applicationof the propelling power than the ordinarycranks, to avoid the noise of pawls and ratchets,and to guard the velocipedes against being overturnedshould one of the rear wheels pass overan obstruction.

Mr. Philip H. Pax on, of Camden, N. J., haspatented a machine that will cut lozenges in aperfect manner, and will not be clogged by thegum and sugar of the lozenge dough.

Mr. John H. Robertson, of New York city, haspatented an improved mat, which consists oflongitudinal metal bars provided with alternatemortised and tenoned ends, and composed ofseries of sockets united by webs and of woodentransverse rods entered through said sockets andheld therein by vertical pins.

Mr. Charles F. Clapp, of Ripon, Wis, haspatented a novel arrangement of a desk attachment fortrunks. The desk and tray may be lifted from the trunkwhen the desk is either raised or lowered.

A combined scraper, chopper, and dirter has been patentedby Messrs. Francis A. Hall and Nathaniel B. Milton,of Monroe, La. The object of this invention is to furnishan implement so constructed as to bar off a row of plants,chop the plants to a stand, and dirt the plants at one passagealong the row, and which shall be simple, convenient, andreliable.

Mr. Hermann H. Cammann, of New York city, has patenteda basket so constructedthat it can be compactlyfolded for transportation orstorage.

Messrs. David H. Seymourand Henry R. A. Boys, ofBarrie, Ontario, Canada, havepatented an improvement inthat class of devices that aredesigned to be applied tosteam cylinders for introducingoil or tallow into the cylinderand upon the cylindervalves. It consists of an oilcup provided with a gas escape,a scum breaker, an interiorgauge, and an adjustablefeed pipe extension.

Mr. John H. Conrad, ofCharlotte, Mich., has patenteda portable sliding gatewhich will dispense withhinges and which can be usedin any width of opening. Itmay be readily connectedwith a temporary opening orgap made in the fence.

An improved reversiblepole and shaft for vehicleshas been patented by Mr.Francis M. Heuett, of JugTavern, Ga. The object ofthis invention is to so combinethe parts of shafts forvehicles that they may bereadily transposed and re-employedto form the tonguewithout removing the thillarms or hounds from the axle.

Mr. William Jones, of Kalamazoo, Mich., has patentedan improved box which is useful for various purposes, butis particularly intended for shipping fourth class mail matter.The feature of special novelty is the means of fasteningthe hinged cover.

Mr. Louis J. Halbert, of Brooklyn, N. Y., has patentedan improved slate cleaner, which is simple, convenient, andeffective.

An improved boot, which is simple in its make, fits well,and is convenient to put on and take off, has been patentedby Ellene A. Bailey, of St. Charles, Mo. The boot is providedwith side seams, one of which is open at its lower end,and is provided with lacing, buttons, or a like device, sothat it can be closed when the boot is on the wearer's foot.

THE HERCULES BEETLE.

In the handsome engraving herewith are shown the maleand female of the Hercules beetle (Dynastes hercules) of Brazil.The family of theDynastidæ comprises some of the largestand most beautiful of the beetlerace, and all of them are remarkablefor enormous developmentsof the thorax and head. Theyare all large bodied and stoutlimbed, and by their greatstrength abundantly justify theirgeneric name,Dynastes, whichis from the Greek and signifiespowerful. The larvæ of thesebeetles inhabit and feed upon decayingtrees and other rottingvegetable matter, and correspondin size with the mature insects.Most of them inhabit tropicalregions, where they perform avaluable service in hastening thedestruction of dead or fallentimber.

An admirable example of thisfamily of beetles is the one hererepresented. In the male of theHercules beetle the upper partof the thorax is prolonged into asingle, downward curving hornfully three inches long, the entirelength of the insect being aboutsix inches. The head is prolongedinto a similar horn, whichcurves upward, giving the headand thorax the appearance oftwo enormous jaws, resemblingthe claw of a lobster. The realjaws of the insect are underneaththe lower horn, which projectsfrom the forepart of the head.The under surface of the thorax-horncarries a ridge of stiff,short, golden-yellow hairs, andthe under surface and edges ofthe abdomen are similarly ornamented.

The head, thorax, and legs areshining black; the elytra, orwing-covers, are olive-green,dotted with black spots, and aremuch wrinkled. The wings arelarge and powerful.

The female Hercules is quiteunlike the male. It is muchsmaller, being not more thanthree and a half inches long, iswithout horns, and is coveredwith a brown hairy felt.

These beetles are nocturnal inhabit, and are rarely seen in thedaytime, except in dark hidingplaces in the recesses of Brazilianforests.

A Poulterer's View of MechanicalPoultry Raising.

A prominent dealer in poultry,Mr. H. W. Knapp, of WashingtonMarket, gives a discouragingopinion of the probable success of chicken raising byartificial means in this country. He said recently whenquestioned on this subject by a representative of theEveningPost:

"I went to France to study the matter, for if it can bemade to succeed it will make an immense fortune, as it hasalready done in Paris. I was delighted with what I sawthere, and the matter at first sight seems to be so fascinatingthat I do not wonder that new men here are always ready totake hold of it as soon as those who have bought dear experienceare only too glad to get out of it. Even clergymenand actors are bitten with the desire to transform so manypounds of corn into so many pounds of spring chicken.The now successful manager, Mackaye, spent about athousand dollars, in constructing hatching machines andartificial mothers in Connecticut, but he found that the stagepaid better, and his expensive devices may now be boughtfor the value of old tin.

"Enthusiasts will tell you that by the new discoverychickens may be made out of corn with absolute certainty.In Paris this has been done; but the conditions are entirelydifferent here. There the land is valuable, and they cannotdevote large fields to a few hundred chickens; the Frenchclimate is so uniform that the markets of Paris cannot besupplied from the south with produce which ripens or maturesbefore that of the neighborhood of Paris; the price ofchickens is so high and labor so cheap that more care canbe given with profit to one spring chicken than one of ourpoultry raisers could give to a dozen. Here we have plentyof land, the climate south of us is so far advanced in warmththat even with steam we cannot raise poultry ahead of thesouth, and the margin of profit is so small that one failurewith a large batch of chickens sweeps away the profits fromseveral successful experiments.

"When persons wanted me to go into the project I declinedand was called an old fogy. One man spent a fortune onthe enterprise in New Jersey, and at first was hailed as apublic benefactor. What was the result of all his outlayand work? He managed to hatch quantities of youngchickens every February, but although he could fatten themby placing them in boxes and forcing a fattening mixturedown their throats, he could not make them grow; they hadno exercise; they remained puny little things, and anotherdefect soon appeared: though fat they were tough andstringy. The breeder sent lots of them to me, and theylooked fat and tender; but my customers complained thatthey could not be young, for they were tough and tasteless,and that I must have sold them aged dwarfs under the nameof spring chickens. It was found absolutely necessary tolet them run out of doors as soon as the weather allowedit, and by the time that they were ready for market thesouthern chickens were here and could be sold for less thanthese. The upshot of the business is that this breeder hassold out, and another man has now taken hold of a smallpart of his old establishment to try other methods of makingit a success.

"As to raising turkeys in that manner it will tail more disastrouslythan the chicken business. Size and weight arewanted in turkeys; and that reminds me," continued Mr.Knapp, "that the newspapers ought to impress the countrypeople with the necessity of improving their poultry stock;breeding in and in is ruining poultry; every year the stockwe receive is deteriorating, and this is the cause. I couldgive you some striking examples from my experience offorty years in the business. Some years ago we poulterersthought that ducks were going to disappear from bills of farealtogether; they were tasteless, worthless birds which peopleavoided. On Long Island a farmer made experiments inbreeding with an old Muscovy drake, tough as an alligator,and the common duck. The result was superb and haschanged the whole duck industry. If the farmers of SouthernNew Jersey, the sandy country best suited to turkeys,would bring from the West a few hundred wild turkeys weshould have an immediate improvement. I see no such turkeynow as we had twenty years ago. The breast is narrowand the body runs to length; it is all neck and legs,and can be bought by the yard.Rhode Island sends us the bestturkeys, but they are not whatthey used to be. If, instead ofattempting to beat nature at herown game, the rich men whohave money to spend would devoteit to better breeding, therewould be an improvement. Ido not yet despair of seeing immensefarms wholly devoted toraising better poultry than weyet have."

The Embrace of the Mantis.

Mr. Addison Ellsworth favorsus with a transcript of a letterfrom Mr. Albert D. Rust, ofEnnis, Ellis County, Texas, describinga remarkable exhibitionof copulative cannibalism onthe part of the mantis. The ferociousnature of these strangeinsects is well known, and is instriking contrast with the popularname, "praying mantis,"which they have gained by thepious attitude they take whilewatching for the flies and otherinsects which they feed upon.

About sunrise, August 28,1880, Mr. Rust's attention wasattracted by a pair of mantis,whetherMantis religiosa or not,he was not sure, but from thelength of the body and the shortnessof the wings he was inclinedto think them of some otherspecies. The female had herarms tightly clasped around thehead of the male, while his leftarm was around her neck. Mr.Rust watched intently to seewhether the embrace was one ofwar or for copulation. It provedto be both. As the two abdomensbegan to approach eachother the female made a ferociousattack upon the male, greedilydevouring his head, a part of thebody, and all the arm that hadencircled her neck. A momentafter the eating began, Mr. Rustobserved a complete union of thesexual organs, and the eating andcopulation went on together.On being forcibly separated thefemale exhibited signs of fear ather headless mate, and it waswith difficulty that they werebrought together again. On beingsuddenly tossed upon theback of the female the maleseized her with a grasp fromwhich she could not extricate herself, and immediatelythe sexual union was renewed, to all appearances as perfectlyas before.

The pair were accidentally killed, otherwise, Mr. Rushthinks, the female would have continued her cannibalisticrepast until she had devoured the entire body of her companion.

This peculiarity of the mantis seems not to havebeen observed before, though their mutually destructive dispositionhas been noted by several. Desiring to study thedevelopment of these insects, M. Roesel raised a brood ofthem from a bag of eggs. Though plentifully suppliedwith flies, the young mantis fought each other constantly,the stronger devouring the weaker, until but one wasleft.

M. Poiret was not more successful. When a pair of mantiswere put together in a glass they fought viciously, the fightending with the decapitation of the male and his beingeaten by the female.

VARIEGATION OF LEAVES.

BY JAMES HOGG.

At the meeting of the Association of Nurserymen inChicago, last July, one of our prominent horticulturists describedleaf variegation as a disease. Incidentally this broughtup the question: Does the graft affect the stock upon whichit is inserted?

Much confusion of ideas exists upon this subject, largelydue to a loose application of the term disease. Strictlyspeaking, this term is only applicable to that which showsthe health of the plant to be impaired. It should be distinguishedfrom aberrant or abnormal forms, for these arenot necessarily indicative of disease. Nobody thinks of sayingthat red or striped roses are diseased because they aredepartures in color from the white flower of the type species;or that white, yellow, or striped roses are diseased when thecolor of the type species is red. Nobody thinks of sayingthat double flowers are evidences of disease in the plant, orthat diminution in the size of leaves or variation in theirform is a disease. Why then should it be said that becauseleaves may become of some other color than green, or becomeparty-colored, therefore they are diseased? If it be saidthat flowers are not leaves, and that therefore the analogy isnot a good one, the reply is, that flowers in all their parts,and fruits also, are only leaves differently developed fromthe type. This fact is a proven one, and so admitted to be byall botanists and vegetable physiologists of the present day.If it be objected that by becoming double, flowers lose thepower of reproducing the variety or species, the answer is,that this loss of power is not necessarily the result of disease,but may arise from various other causes. Because an animalis castrated, it surely will not be claimed that thereforeit is diseased. In man and in the higher animals the powerof reproduction ceases at certain ages, but it cannot thereforebe said that such men or animals are diseased. Neitheris a redundancy of parts an unequivocal evidence of disease.

Topknot fowls and ducks are as healthy as those which donot have such appendages, and a Shetland pony is as healthyas a Percheron horse, notwithstanding the difference in theirsize and weight. Again, color in block or in variegation isnot positive evidence of disease in animal life. The whiteCaucasian is as healthy as the negro, the copper-coloredMalay as the red Indian. The horse, ox, and hog run throughwhite and red to black both in solid and party-color, and allare equally healthy; so with the rabbit, dog, cat, and othersof our domestic animals. In wild animals, birds, reptiles,fishes, and insects, it is the same, so that mere difference incolor or combinations of color are notprima facie evidenceof disease.

But some will say this may be true of animal life, but notof plant life. That there is a strong and evident analogy,the one with the other, is now universally admitted by physiologists.Formerly many physiologists considered leaf variegationa disease, because it generally ran in stripes lengthwiseof the leaf or in spots. In the former case it was supposedto originate from disease in the leaf cells of the leafstalk, which, as the cells grow longitudinally, naturally prolongedit to the end of the leaf. But the originating of varietiesin which the variegation did not assume this form, withother considerations, has done much to upset this theory.In the variegated leaved snowberry we have the center andborder of the leaf green, separated the one from the other byan isolated white or yellow zone. In the zebra-leaved eulaliaand the zebra-leaved juncus, from Japan, we have the variegationof the leaf transversely instead of longitudinally, sothat according to the old theory we have the anomaly of ahealthy portion of the leaf producing an unhealthy portion,and that again a healthy one, and thus alternately along thewhole length of the leaf.

When we dissect a leaf in its primal development, we findthat its cells contain colorless globules, by botanists calledchlorophyl or phyto-color; these undergo changes accordingas they are acted upon by light, oxygen, or other agents,producing green, yellow, red, and other tints. This chlorophylonly exists in the outer or superficial cells of theparenchyma or cellular tissue of the leaf, and thus differsfrom starch and other substances produced in the internalcells, from which the light is more or less excluded. It is afatty or wax-like substance, readily dissolved in alcohol orether. The primal color of all leaves and flowers iswhite or a pale yellowish hue, as can readily be seen by cuttingopen a leaf or flower bud. The seed leaves of the Frenchbean are white when they come out of the earth, but theybecome green an hour afterward under the influence of brightsunshine. A case is on record where in a certain section,some miles in extent, in this country, about the time of thetrees coming into leaf, the sun did not shine for twenty days;the leaves developed to nearly their full size, but were of apale or whitish color; finally, one forenoon the sun shone outfully, and by the middle of the afternoon the trees were infull summer dress. These facts show that the green colorof leaves is due to the action of light. Variegation is sometimesproduced independently of the chlorophyl, as inBegoniaargyrostigma andCarduus marianus, in which it is producedby a layer of air interposed between the epidermis or outerskin of the leaf and the cells beneath; this gives the leaf abright, silvery appearance.

To what, then, are we to ascribe leaf variegation? I thinkthat it is entirely due to diminished root power; by this I donot mean that the roots are diseased, but that they are eitherin an aberrant or abnormal state; but disease cannot be predicatedupon either of these states. To explain: everybodyknowsSpirea callosa to be a strong growing shrub, havingumbels of rosy-colored flowers and strong, stout roots; thewhite flowered variety is quite dwarf, is more leafy andbushy than the species, and has more fibrous and delicateroots than the type; the crisp-leaved variety is still moredwarf, very bushy, and very leafy, and has very fine threadlikeroots. This would indicate that the aberrance is in theroots; the two varieties are much more leafy in proportionto their size than the species, so that if the leaves controlledthe roots, the latter should have been larger in proportionthan those of the species. Again, once when, in theautumn, I was preparing my greenhouse plants for their winterquarters, I cut back a "Lady Plymouth" geranium,which chanced to be set away in a cool and somewhat dampcellar. When discovered the following February and startedinto growth in the greenhouse it produced nothing but solidgreen leaves, and never afterward produced a variegatedleaf. This I attributed to its having gained greater rootpower during its long season of rest. By this I mean thatthe roots had grown and greatly increased in size, althoughthere had not been any leaf growth. That roots under certaincircumstances do so is well known. The roots of firtrees have been found alive and growing forty five years afterthe trunks were felled. The same has occurred in an ashtree after its trunk had been sawn off level with the ground.A root ofIpomea sellowii has been known to keep on growingfor twelve years after its top had been destroyed by frost;and in all that time it never made buds or leaves, yet it increasedto seven times its original weight. The tuberousroots of some of theTropæolums will continue to grow andincrease in size after the tops have been accidentally brokenoff; and potatoes buried so deep in the earth that they cannotproduce tops will produce a crop of new potatoes.

On the other hand, I have had an oak-leaved geraniumoverlooked in a corner of the greenhouse until it was almostdried up for lack of water. When its branches were prunedback and it was started into growth only one branch showedthe almost black center of the leaf, all the rest were cleargreen. This was an evident case of diminished root power,but the plant grew as thriftily as ever. The lack of the darkmarking in the leaves was equivalent to the variegation inother varieties, only in a reverse direction.

In practice, when gardeners wish to produce an abnormalcondition in a tree or plant, they will, if they wish to dwarfit, graft it on a species or variety of diminished root power,and contrariwise, if they wish to increase its growth, willgraft it upon a stock of strong root power. But in neithercase can the graft be said to be diseased by the action of theroots of the stock.

When this root power is so far diminished as to producecomplete albinism, the shoots from such roots appear to partakeof this diminished power, and to lose the power ofmaking roots, and thus become very difficult to propagate.It is sometimes said that albino cuttings cannot be rooted atall, but this is a mistake, for I have succeeded in strikingsuch cuttings from the variegated leavedHydrangea. It requiredmuch care to do it; they did not, however, retaintheir albino character after they rooted and started intogrowth.

Albinism and white variegation in leaves appear to bedue to the chlorophyl in such leaves being able to resist theaction of the three (red, yellow, and blue) rays of light.What we call color in any substance or thing is due to its reflectingthese different rays in various proportions of combinationand absorbing the rest of them, the various proportionsgiving the various shades of color. White is due tothe reflection of all of them, and black to the absorption ofthem. In some plants with variegated foliage we have thecurious fact that the cells containing chlorophyl reflectingone color produce cells which reflect an entirely differentcolor. In the coleus "Lady Burrill," for instance, thelower half of the leaf is of a deep violet-crimson color, andthe upper half is golden yellow. In other varieties of coleus,inPerilla nankiensis, and other plants, we have foliage withouta particle of green in it, and yet they are perfectlyhealthy. This shows that green leaves are not absolutelynecessary to the health of a plant.

As a proof of leaf variegation being a disease, the speakeralluded to cited a case in which a green leaved abutilon,upon which a variegated leaved variety had been grafted,threw out a variegated leaved shoot below the graft. Thiscan easily be explained. The growth of the trunk or stemof all exogenous plants, or those which increase in size onthe outside of the stem, is brought about by the descent ofcertain formative tissue called cambium, elaborated by theleaves and descending between the old wood and the bark,where it is formed into alburnum or woody matter. Somethink that it is also formed by the roots and ascends fromthem as well as descending from the leaves. Be this as itmay, there is no doubt about its descent. In such comparativelysoft-wooded, free growing plants as the abutilonthe descent of the cambium is very free and in considerablequantity, so that the stock would soon be inclosed in a layerof it descending from the graft. When being convertedinto woody matter it also forms adventitious buds whichunder certain favorable circumstances will emit shoots of thesame character as the graft from which it was derived.The graft is such cases may be said to inclose the stock in atube of its own substance, leaving the stock unaffectedotherwise. The variegated shoot in this case was in realityderived from the downward growth of the graft and notfrom the original stock, which was not therefore contaminatedby the graft. In cases where the stock is of muchslower growth than the graft, or the graft is inserted upona stock of some other species, the descending cambium doesnot inclose the stock, but makes layers of wood on the stemof the graft, which thus, as is frequently seen, overgrows thestock, sometimes to such an extent as to make it unsightly.Nobody ever saw an apple shoot from a crab stock, a pearfrom a quince stock, or a peach shoot from a plum stock.This is one of the arguments in favor of the view that cambiumalso rises from the roots.

Again, to show that the stock is not affected by the graft,or the graft by the stock, except as to root power, let anyperson graft a white beet upon a red beet, or contrariwise,when about the size of a goosequill, and when they have attainedtheir full growth, by dividing the beet lengthwise hewill find the line of demarkation between the colors perfectlydistinct, neither of them running into the other.

The theory that leaf variegation is a disease has been heldby many distinguished botanists and is in nowise new. Butthis theory has been controverted, and we think successfully,by other botanists, and it is not now accepted by the moreadvanced vegetable physiologists. There are now so manyacute and industrious students and observers in every departmentof science, and the accumulation of facts is sorapid and so great, that very many of the older theories arebeing set aside as not in accord with the newly discoveredfacts. A student brought up in institutions where the oldtheories are inculcated has afterward to spend half his timein unlearning what he had been previously taught, and theother half in studying the new facts brought to his noticeand testing the theories promulgated by men of science.Botanical science does not wholly consist in the classificationand nomenclature of plants, but largely consists in a knowledgeof vegetable anatomy and physiology, and these requiremuch study and some knowledge of other sciences, suchas chemistry, meteorology, geology, etc. Without suchgeneral knowledge it is difficult to form a harmonious theoryin regard to any of the phenomena of plant life.

Vanilla, Cinnamon, Cocoanut.

The following interesting facts concerning the cultivationof the above products in the island of Ceylon, were given inMr. H. B. Brady's recent address before the British PharmaceuticalConference at Swansea:

The vanilla plant is trained on poles placed about twelveor eighteen inches apart—one planter has a line of plantsabout three miles in length. Like the cardamom, it yieldsfruit after three years, and then continues producing itspods for an indefinite period.

The cinnamon (Cinnamomum zeylanicum) is, as its nameindicates, a native of Ceylon. It is cultivated on a lightsandy soil about three miles from the sea, on the southwestcoast of the island, from Negumbo to Matura. In its cultivatedstate it becomes really productive after the sixth year,and continues from forty to sixty years. The superintendentof the largest estate in this neighborhood stated thatthere were not less than fifteen varieties of cinnamon, sufficientlydistinct in flavor to be easily recognized. The productionof the best so injures the plants that it does not payto cut this at any price under 4s. 6d. to 5s. per lb. Theestate alluded to above yields from 30,000 to 40,000 lb. perannum; a uniform rate of 4-1/2 d. per lb. of finished bark ispaid for the labor. Cinnamon oil is produced from thisbark by distillation; the mode is very primitive and wasteful.About 40 lb. of bark, previously macerated in water,form one charge for the still, which is heated over a firemade of the spent bark of a previous distillation. Eachcharge of bark yields about three ounces of oil, and twocharges are worked daily in each still.

The cultivation of the cocoanut tree and the productionof the valuable cocoanut oil are two important Cingaleseoccupations. These trees, it appears, do not grow with anyluxuriance at a distance from human dwellings, a factwhich may perhaps be accounted for by the benefit they derivefrom the smoke inseparable from the fires in humanhabitations. The cultivation of cocoanuts would seem tobe decidedly profitable, as some 4,000 nuts per year areyielded by each acre, the selling price being £3 per thousand,while the cost of cultivation is about £2 per acre. Inextracting the oil, the white pulp is removed and dried,roughly powdered, and pressed in similar machinery to thelinseed oil crushing mills of this country. The dried pulpyields about 63 per cent by weight of limpid, colorless oil,which in our climate forms the white mass so well knownin pharmacy.

Learning to Tie Knots.

A correspondent suggests that it would be a handy accomplishmentfor schoolboys to be proficient in the handling,splicing, hitching, and knotting of ropes. He suggeststhe propriety of having the art taught in our public schools.A common jackknife and a few pieces of clothes line are themain appliances needed to impart the instruction with. Heconcludes it would not only be of use in ordinary daily life,but especially to those who handle merchandise and machinery.Any one, he adds, who has noticed the clumsy haphazardmanner in which boxes and goods are tied for hoistingor for loading upon trucks, will appreciate the advantage ofpractical instruction in this direction. Probably a goodplan, he further suggests, would be to have one schoolboytaught first by the master, and then let the pupil teach theother boys. Our correspondent thinks most boys wouldconsider it a nice pastime to practice during recess and atthe dinner hour, so that no time would be taken from studyor recitation time.

DECISIONS RELATING TO PATENTS.

Supreme Court of the United States

Appeal from the Circuit Court of the United States forthe Southern District of New York.

1. Reissued patent No. 5,774 to Shubael Cottle, February24, 1874, for improvement in chains for necklaces, declaredvoid, the first claim, if not for want of novelty, for want ofpatentability, and the second for want of novelty.

2. Neither the tubing, nor the open spiral link formed oftubing, nor the process of making either the open or theclosed link, nor the junction of closed and open spiral linksin a chain, was invented by the patentee.

3. All improvement is not invention and entitled to protectionas such. Thus to entitle it it must be the productof some exercise of the inventive faculties, and it must involvesomething more than what is obvious to personsskilled in the art to which it relates.

The decree of the circuit court is therefore reversed, andit is ordered that the bill be dismissed.

By the Commissioner of Patents.

The subject matter of the interference is defined in thepreliminary declaration thereof as follows:

The combination in one instrument of a transmitting telephoneand a receiving telephone, so arranged that when themouthpiece of the speaking or transmitting telephone is appliedto the mouth of a person, the orifice of the receivingtelephone will be applied to his ear.

1. While it is true that the unsupported allegations of aninventor, that he conceived an invention at a certain date, arenot sufficient to establish such fact, the testimony of a partythat he constructed and used a device at a certain time isadmissible.

2. Abandonment is an ill-favored finding, which cannotbe presumed, but must be conclusively proven.

The decision of the Board of Examiners-in-Chief is reversed,and priority awarded to Dickson.

Characteristics of Arctic Winter.

Lieutenant Schwatka, whose recent return from a successfulexpedition in search of the remains of Sir JohnFanklin's ill-fated company, combats the prevalent opinionthat the Arctic winter, especially in the higher latitudes, isa period of dreary darkness.

In latitude 83° 20' 20" N., the highest point ever reachedby man, there are four hours and forty-two minutes of twilighton December 22, the shortest day in the year, in thenorthern hemisphere. In latitude 82° 27' N., the highestpoint where white men have wintered, there are six hoursand two minutes in the shortest day; and latitude 84° 32'N., 172 geographical miles nearer the North Pole thanMarkham reached, and 328 geographical miles from thatpoint, must yet be attained before the true Plutonic zone, orthat one in which there is no twilight whatsoever, even uponthe shortest day of the year, can be said to have been enteredby man. Of course, about the beginning and endingof this twilight, it is very feeble and easily extinguished byeven the slightest mists, but nevertheless it exists, and isquite appreciable on clear cold days, or nights, properlyspeaking. The North Pole itself is only shrouded in perfectblackness from November 13 to January 29, a period ofseventy-seven days. Supposing that the sun has set (supposinga circumpolar sea or body of water unlimited tovision) on September 24, not to rise until March 18, for thatparticular point, giving a period of about fifty days of uniformlyvarying twilight, the pole has about 188 days of continuousdaylight, 100 days of varying twilight, and 77 ofperfect inky darkness (save when the moon has a northerndeclination) in the period of a typical year. During theperiod of a little over four days, the sun shines continuouslyon both the North and South Poles at the same time,owing to refraction parallax, semi-diameter, and dip of thehorizon.

The Collins Line of Steamers.

The breaking up of the Baltic, the last of the famous Collinsline of steamships, calls out a number of interesting factswith regard to the history of the several vessels of that fleet.There were five in all, the Adriatic, Atlantic, Pacific, Arctic,and Baltic. They were built and equipped in New York.Their dimensions were: Length, 290 feet; beam, 45 feet;depth of hold, 31½ feet; capacity, 2,860 tons; machinery,1,000 horse power. In size, speed, and appointments theysurpassed any steamers then afloat, and they obtained a fair shareof the passenger traffic. A fortune was expended indecorating the saloons. The entire cost of each steamer wasnot less than $600,000, and notwithstanding their quick passages,the subsidy received, and the high rates of freight paid,the steamers ran for six years at great loss, and finally thecompany became bankrupt.

The Atlantic was the pioneer steamship of the line. Shesailed from New York April 27, 1849, and arrived in the MerseyMay 10, thus making the passage in about thirteen days,two of which were lost in repairing the machinery; thespeed was reduced in order to prevent the floats from beingtorn from the paddle-wheels. The average time of theforty-two westward trips in the early days of the line was 11days 10 hours and 26 minutes, against the average of thethen so called fastest line of steamers, 12 days 19 hours and26 minutes. In February, 1852, the Arctic made the passagefrom New York to Liverpool in 9 days and 17 hours.

The Arctic was afterward run into by a French vessel at seaand only a few of her passengers were saved. The Pacificwas never heard from after sailing from Liverpool, and allthe persons on board were lost. The Atlantic, after rottingand rusting at her wharf, was deprived of her machineryand converted into a sailing vessel, and was broken up inNew York last year. The Adriatic, the "queen of the fleet,"made less than a half dozen voyages, was sold to the GalwayCompany, and is now used in the Western Islands as a coalhulk by an English company.

The Baltic was in the government service during the waras a supply vessel, and was afterward sold at auction;her machinery was removed and sold as old iron. She wasthen converted into a sailing ship, and of late years has beenused as a grain carrying vessel between San Francisco andGreat Britain. On a recent voyage to Boston she was strainedto such an extent as to be made unseaworthy, and for thatreason is to be broken up.

One cannot but remark in this connection how small hasbeen the advance in steamship building during the quartercentury since the Collins line was in its glory.

CHINESE WOMEN'S FEET.

An American missionary, Miss Norwood, of Swatow, recentlydescribed in aTimes paragraph how the size of thefoot is reduced in Chinese women. The binding of the feetis not begun till the child has learnt to walk. The bandagesare specially manufactured, and are about two inches wideand two yards long for the first year, five yards long for subsequentyears. The end of the strip is laid on the inside ofthe foot at the instep, then carried over the toes, under thefoot, and round the heel, the toes being thus drawn towardand over the sole, while a bulge is produced on the instep,and a deep indentation in the sole. Successive layers ofbandages are used till the strip is all used, and the end isthen sewn tightly down. The foot is so squeezed upwardthat, in walking, only the ball of the great toe touches theground. After a month the foot is put in hot water to soaksome time; then the bandage is carefully unwound, muchdead cuticle coming off with it. Frequently, too, one ortwo toes may even drop off, in which case the woman feelsafterward repaid by having smaller and more delicate feet.Each time the bandage is taken off, the foot is kneaded tomake the joints more flexible, and is then bound up again asquickly as possible with a fresh bandage, which is drawn upmore tightly. During the first year the pain is so intensethat the sufferer can do nothing, and for about two years thefoot aches continually, and is the seat of a pain which is likethe pricking of sharp needles. With continued rigorousbinding the foot in two years becomes dead and ceases toache, and the whole leg, from the knee downward, becomesshrunk, so as to be little more than skin and bone. Whenonce formed, the "golden lily," as the Chinese lady calls herdelicate little foot, can never recover its original shape.

Our illustrations show the foot both bandaged and unbandaged,and are from photographs kindly forwarded byMr. J. W. Bennington, R.N., who writes: "It is an error tosuppose, as many do, that it is only the Upper Ten amongthe daughters of China that indulge in the luxury of 'goldenlilies,' as it is extremely common among every class, even tothe very poorest—notably the poor sewing women one seesin every Chinese city and town, who can barely manage tohobble from house to house seeking work. The pain enduredwhile under the operation is so severe and continuousthat the poor girls never sleep for long periods without theaid of strong narcotics, and then only but fitfully; and it isfrom this constant suffering that the peculiar sullen or stolidlook so often seen on the woman's face is derived. Theorigin of this custom is involved in mystery to the Westerns.Some say that the strong-minded among the ladies wantedto interfere in politics, and that there is a general liking forvisiting, chattering, and gossip (and China womencanchatter and gossip), both and all of which inclinations theirlords desired, and desire, to stop by crippling them."

To the alteration and metamorphism of rocks by the infiltrationof rain and other meteoric waters, M. De Koninck, ofthe Belgian Academy of Sciences, assigns the cause ofmany hitherto unexplained phenomena in geology.

CORRESPONDENCE

Ice at High Temperatures.

Your issues of October 23 and 30 contain some remarkablearticles under the heading of "Ice at High Temperatures."

Prof. Carnelley says; "In order to convert a solid into aliquid, thepressure must be above a certain point, otherwiseno amount of heat will melt the substance," as it passes atonce from the sold state into the state of gas, subliming awaywithout previous melting. And, "having come to this conclusion,it was easily foreseen that it would be possible tohave solid ice at temperatures far above the ordinary meltingpoint."

The first conclusion of the professor is correct, but notnew. The second conclusion is new, but very doubtful asto its correctness, and certainly does not follow as a sequencefrom his premise.

If we try to heat ice in a vacuum, we cannot apply anyheat to the ice direct, but only to the vessel containing theice. The vessel may be much heated; but whether it willconvey heat to the ice quick enough to heat it over 32°, andwhether at all it can be heated over 32°, this is a question ofa different nature. Before crediting such a conclusion wemust know more of the details of the experiments which theprofessor made in order to verify its correctness. Whensaying that "on one occasion a small quantity of water wasfrozen in a glass vessel which was so hot that it could not betouched by the hand without burning it," he evidently assumesthat if the vessel is hot, the ice inside must be equallyso; but this assumption is erroneous. Faraday has madewater to freeze in a red hot platina pot; the ice thus formedwas not red hot like the platina, but was below the freezingpoint. Just so with Professor Carnelley's glass vessel: thevessel was hot, but the ice inside no doubt was "ice cold."If the professor would surround a thermometer bulb withice and then make the mercury rise above the freezing point,we would believe in "hot ice;" not before. Until he does,we prefer to believe that the heat conveyed through the vesselto the ice is all absorbed in vaporizing the ice, and notin raising its temperature above 32°.

Professor Carnelley's further statement, apparently provinghis theory, that the ice at once liquefies as soon as pressureis admitted (say by admitting air), is readily accountedfor by the phenomena connected with the "LeydenfrostDrop." Water in a red hot vessel will vaporize off muchslower than in a vessel heated a little above the boiling point,from the reason that in the red hot vessel noreal contacttakes place between the vessel and the water. At the placewhere the two ought to touch, steam is formed quicker thanit can escape, which steam prevents the contact between vesseland water; therefore, as no real contact takes place, theheat from the vessel can pass into the water but slowly, viz.,in the proportion as it works itself through the layer ofsteam, which in itself is a bad conductor. Just so in Prof.Carnelley's experiment: The heated glass vessel will conveyheat to the ice only at those points where it touches the ice;at those points at once a formation of vapor takes place,which prevents an intimate contact between the glass andthe ice, so that they do not really touch each other, consequentlythe heat can pass into the ice but slowly, having towork its way through the thin layer of rarefied vapor betweenthe two. As soon as pressure is admitted by admittingatmospheric air, vapors can no longer form; an intimatecontact will take place between the glass and the ice, andconsequently the heat be conveyed over quick enough tomake the ice melt away rapidly.

The professor's experiments, therefore, so far as published,do not prove anything to justify his strange conclusion. Itis perfectly true that in a vacuum of less than 4.6 mm. mercurypressure, no amount of heat will melt ice, all heat thatcan be conveyed to the ice being absorbed by vaporization.But before crediting the professor's further conclusion, thatice can be heated much above the freezing point, he mustactually produce "hot ice," not only a hot vessel containingice. N. J.

Schools of Invention.

The school of invention has not yet been established, butits germ is growing in the mechanical schools. This school,according to Hon. W. H. Ruffner, inVa. Ed. Journal, willeducate men, and women too, for the special career of inventingnew things. Why not? We already have somethingclosely analogous in schools of design, where the pupil istrained to invent new forms or patterns, chiefly of an artisticor decorative character. The same idea will be applied to theinvention of machinery, or improvements in machinery, orthe adaptation of machinery to the accomplishment of specialends. Inventions usually spring from individuals strivingto lighten their own labor, or from some idea enteringthe brain of a genius. But we shall have professional inventorswho will be called on to contrive original devices,and his success will depend on the sound and practical characterof his prescriptions.

Proposed Exhibition of Bathing Appliances.

The Board of Health of this city has recently been notifiedthat a Balneological Exhibition, to illustrate the various systemsof bathing, bath appliances, and kindred matters, is tobe held in Frankfort-On-Main, Germany, next summer. Theexhibition will last from May to September, 1881.

H. H. Heinrich, No. 41 Maiden Lane, New York, InventorPatentee, and Sole Manufacturer of the Self-AdjustingChronometer Balance, which is not affectedby "extremes of high and low temperatures, as fullydemonstrated by a six months' test at the Naval Observatoryat Washington, D. C., showing results in temperaturesfrom 134° down to 18°, of 5-10 of a second only,unparalleled in the history of horology and certified toby Theo F. Kone. Esq., Commander U. S. N. in chargeof the Observatory. Mr. Heinrich is a practical workingmechanic and adjuster of marine and pocket chronometersto positions and temperatures, and is now preparedto apply his new balance wheel to any fine timekeepinginstrument, either for public or private use, healso repairs marine and pocket chronometers, as well asall kinds of complicated watches, broken or lost partsmade new and adjusted. Mr. Heinrich was connectedfor many years with the principal manufacturers ofEngland, Geneva and Locle, Switzerland, and for thelast fifteen years in the United States, and very recentlywith Messrs. Tiffany & Co., of Union Square, New York.Shipowners, captains naval and army officers, railroadand telegraph officials, physicians and horsemen, and allothers wanting true time, should send to him. Finewatches of the principal manufacturers, for whom he istheir agent, constantly on hand. His office is connectedby electric wires with the Naval Observatory's astronomicalclock, through the Western Union Telegraph, thusgiving him daily New York's mean time. Many yearsago the British Government made an offer of £6,000 for achronometer for her navy, keeping better time than theones in use, but no European horologist ever discoveredthe sequel which Mr. Heinrich has now worked out toperfection, overcoming the extremes, as stated above.With him is connected Mr. John P. Krugler for thirtyyears connected with the trade as salesman.—Adv.

Toope's Felt and Asbestos Covering for Steam Pipesand other surfaces, illustrated on page 357, present volume,received a Medal of Excellence at the late AmericanInstitute Fair. See advertisement on another page.

Business and Personal.

The Charge for Insertion under this head is One Dollara line for each insertion; about eight words to a line.Advertisements must be received at publication officeas early as Thursday morning to appear in next issue.

The publishers of this paper guarantee to advertisersa circulation of not less than 50,000 copies everyweekly issue.

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Three requisites—pens, pins, and needles. The twolatter you can get of any make, but when you want agood pen get one of Esterbrook's.

For Heavy Punches, etc., see illustrated advertisementof Hilles & Jones, on page 380.

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Among the numerous Mowing Machines now in use,none ranks so high as the Eureka. It does perfect workand gives universal satisfaction. Farmers in want of amowing machine will consult their best interests bysending for illustrated circular, to Eureka Mower Company,Towanda, Pa.

The Inventors Institute, Cooper Union Building, NewYork. Sales of patent rights negotiated and inventionsexhibited for subscribers. Send for circular.

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The E. Stebbins Manuf'g Co. (Brightwood, P. O.),Springfield, Mass., are prepared to furnish all kinds ofBrass and Composition Castings at short notice; alsoBabbitt Metal. The quality of the work is what hasgiven this foundry its high reputation. All workguaranteed.

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The Tools, Fixtures, and Patterns of the TauntonFoundry and Machine Company for sale, by the GeorgePlace Machinery Agency, 121 Chambers St., New York.

Improved Rock Drills and Air Compressors, Illustratedcatalogues and information gladly furnished.Address Ingersoll Rock Drill Co., 1-1/2 Park Place. N. Y.

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Experts in Patent Causes and Mechanical Counsel.Park Benjamin & Bro., 50 Astor House, New York.

Corrugated Wrought Iron for Tires on Traction Engines,etc. Sole mfrs. H. Lloyd, Son & Co., Pittsb'g, Pa.

Malleable and Gray Iron Castings, all descriptions, byErie Malleable Iron Company, limited, Erie, Pa.

Power, Foot, and Hand Presses for Metal Workers.Lowest prices. Peerless Punch & Shear Co. 52 Dey St., N. Y.

Recipes and Information on all Industrial Processes.Park Benjamin's Expert Office, 50 Astor House, N. Y.

For the best Stave, Barrel, Keg, and Hogshead Machinery,address H. A. Crossley, Cleveland, Ohio.

National Steel Tube Cleaner for boiler tubes. Adjustable,durable. Chalmers-Spence Co., 40 John St., N. Y.For Mill Mach'y & Mill Furnishing, see illus. adv. p. 349.

The Brown Automatic Cut-off Engine; unexcelled forworkmanship, economy, and durability. Write for information.C. H. Brown & Co., Fitchburg, Mass.

Best Oak Tanned Leather Belting. Wm. F. Forepaugh,Jr., & Bros., 531 Jefferson St., Philadelphia, Pa.

Stave, Barrel, Keg, and Hogshead Machinery a specialty,by E. & B. Holmes, Buffalo, N. Y.

Split Pulleys at low prices, and of same strength andappearance as Whole Pulleys. Yocom & Son's ShaftingWorks, Drinker St., Philadelphia. Pa.

C. B. Rogers & Co., Norwich, Conn., Wood WorkingMachinery of every kind. See adv., page 348.

National Institute of Steam and Mechanical Engineering,Bridgeport, Conn. Blast Furnace Construction andManagement. The metallurgy of iron and steel. PracticalInstruction in Steam Engineering, and a good situationwhen competent. Send for pamphlet.

Reed's Sectional Covering for steam surfaces; anyone can apply it; can be removed and replaced withoutinjury. J. A. Locke, Agt., 32 Cortlandt St., N.Y.

Downer's Cleaning and Polishing Oil for bright metals,is the oldest and best in the market. Highly recommendedby the New York, Boston, and other Fire Departmentsthroughout the country. For quickness ofcleaning and luster produced it has no equal. Samplefive gallon can be sent C. O. D. for $8. A. H. Downer, 17Peck Slip, New York.

Presses. Dies, and Tools for working Sheet Metal, etc.Fruit & other can tools. Bliss & Williams, B'klyn, N. Y.

For Pat. Safety Elevators, Hoisting Engines. FrictionClutch Pulleys, Cut-off Coupling, see Frisbie's ad. p. 349.

Nickel Plating.—Sole manufacturers cast nickel anodes,pure nickel salts, importers Vienna lime, crocus,etc. Condit. Hanson & Van Winkle, Newark, N. J., and92 and 94 Liberty St., New York.

Wright's Patent Steam Engine, with automatic cutoff. The best engine made. For prices, address WilliamWright, Manufacturer, Newburgh, N. Y.

Machine Knives for Wood-working Machinery, BookBinders, and Paper Mills. Also manufacturers of Soloman'sParallel Vise, Taylor, Stiles & Co., Riegelsville, N. J.

Fire Brick, Tile, and Clay Retorts, all shapes. Borgner& O'Brien, M'f'rs, 23d St., above Race, Phila., Pa.

Steam Hammers, Improved Hydraulic Jacks, and TubeExpanders. R. Dudgeon, 24 Columbia St., New York.

Peerless Colors—For coloring mortar. French, Richards& Co., 410 Callowhill St., Philadelphia, Pa.

Tight and Slack Barrel machinery a specialty. JohnGreenwood & Co., Rochester, N. Y. See illus. adv. p. 380.

Elevators, Freight and Passenger, Shafting, Pulleysand Hangers. L. S. Graves & Son, Rochester, N. Y.

Steam Engines; Eclipse Safety Sectional Boiler. LambertvilleIron Works, Lambertville, N. J. See ad. p. 349.

Magic Lanterns, Stereopticons, and Views of all kindsand prices for public exhibitions. A profitable businessfor a person with small capital. Also lanterns for homeamusement, etc. Send stamp for 116 page catalogue toMcAllister, M'f'g Optician, 49 Nassau St., New York.

Lenses for Constructing Telescopes, as inSci. Am.Supplement, No. 252, $6.50 per set; postage, 9 cts. Thesame, with eye piece handsomely mounted in brass,8.00. McAllister, M'f'g Optician, 49 Nassau St., N. Y.

For best low price Planer and Matcher, and latestimproved Sash, Door, and Blind Machinery, Send forcatalogue to Rowley & Hermance, Williamsport, Pa.

The only economical and practical Gas Engine in themarket is the new "Otto" Silent, built by Schleicher,Schumm & Co., Philadelphia, Pa. Send for circular.

Tyson Vase Engine, small motor. 1-33 H. P., efficientand non-explosive: price $50 See illus. adv., page 380.

English Patents Issued to Americans.

From November 9 to November 12, 1880, inclusive.

Book binding, L. Finger, Boston, Mass.
Draining and sewerage. G. E. Waring Newport, R. I.
Electric gas lighter, G. D. Bancroft. Boston, Mass.
Electric signal. EH Johnsonet al., Menlo Park, N. J.
Horse nail manufacture, S. S. Putnam. Boston, Mass.
Hygienic confection, T. S. Lambertet al., New York city.
Looms, F. O. Tucker, Hartford, Conn.
Reflectors for lamps. J. S. Goldsmith, New York city.
Railroad vehicles, E. R. Esmondet al.. New York city.
Sewing machine. G. F. Newell, Greenfield. Mass.
Steam boilers, D. Sutton. Cincinnati. Ohio.
Steam boilers, W. D. Dickey, New York city.
Toy money box, J. E. Walter. New York city.
Trucks, hand., E. J. Lyburn, Fredericksburg, U. S. A.

HINTS TO CORRESPONDENTS.

No attention will be paid to communications unless accompanied withthe full name and address of the writer.

We renew our request that correspondents, in referring to formeranswers or articles, will be kind enough to name the date of thepaper and the page, or the number of the question.

Correspondents whose inquiries do not appear after a reasonable timeshould repeat them. If not then published, they may conclude that,for good reasons, the Editor declines them.

Persons desiring special information which is purely of a personalcharacter, and not of general interest, should remit from $1 to $5,according to the subject, as we cannot be expected to spend time andlabor to obtain such information without remuneration.

Any numbers of theScientific American Supplement referred to inthese columns may be had at this office. Price 10 cents each.

(1) L. L. asks: 1. How can I grind and polish quartz and agate rock,and what kind of grinding and polishing material should I use? A.Quartz and agate are slit with a thin iron disk supplied withdiamond dust moistened with brick oil. The rough grinding is done ona lead wheel supplied with coarse emery and water. The smoothing isdone with a lead lap and fine emery, and the polishing may beaccomplished by means of a lead lap, whose surface is hacked andsupplied with rottenstone and water. 2. What is the best method ofpolishing steel? A. The usual method is to grind first on a coarsewet stone, then on a fine wet stone, then on a lead lap suppliedwith fine emery and oil, and finally polish on a buff wheel suppliedwith dry crocus and revolving rather slowly.

(2) R. L. J. asks how to make copying black and red inks. A. 1.Bruised Aleppo nutgalls, 2 lb.; water, 1 gallon; boil in a coppervessel for an hour, adding water to make up for that lost byevaporation; strain and again boil the galls with a gallon of waterand strain; mix the liquors, and add immediately 10 oz. of copperasin coarse powder and 8 oz. of gum arabic; agitate until solution ofthese latter is effected, add a few drops of solution of potassiumpermanganate, strain through a piece of hair cloth, and afterpermitting to settle, bottle. The addition of a little extract oflogwood will render the ink blacker when first written with. Half anounce of sugar to the gallon will render it a good copying ink. 2.Shellac, 4 oz.; borax, 2 oz.; water, 1 quart; boil till dissolved,and add 2 oz. of gum arabic dissolved in a little hot water; boiland add enough of a well triturated mixture of equal parts indigoand lampblack to produce the proper color; after standing severalhours draw off and bottle. 3. Half a drachm of powdered drop lakeand 18 grains of powdered gum arabic dissolved in 3 oz. of ammoniawater constitute one of the finest red or carmine inks.

(3) X. inquires: What is the rule for making a counterbalanced facewheel for engines? A. It is a common practice to place the counterweight directly opposite the crank, with its center of gravity atthe same distance from the center of the shaft as the center of thecrank pin, making its weight equal to weight of piston, piston rod,crosshead, and crank pin, plus half the weight of the connectingrod.

(4) A. R. asks: What is the best way to remove cinders from the eye?A. A small camel's hair brush dipped in water and passed over theball of the eye on raising the lid. The operation requires no skill,takes but a moment, and instantly removes any cinder or particle ofdust or dirt without inflaming the eye.

(5) D. F. H. asks: Can I move a piston in a half inch glass tube bythe expansion of mercury? A. Yes, but you will require a long tubeto get any appreciable motion of the piston.

(6) J. W. asks: What size of a bore and what length of a stroke Iwould want for a rocking valve engine of half a horse power? A.About 2 inches cylinder and 3 inch stroke, depending upon pressureand velocity.

(7) R. W. H. writes: In a recent discussion on hot air and steamportable engines it was decided to ask your opinion, which should befinal. Water is scarce, though enough to use steam is easilyprocured. The country is hilly, so that lightness is desirable. Thepower wanted is 6 horse, and movable, that is, on wheels. Which willbe best, hot air engine or steam engine? Which consumes most coalfor a given power? Which will be cheapest in above case? A. Forsmall powers the hot air engine is most economical, but we do notthink it adapted to your purpose. We would recommend the steamengine for a portable power.

(8) J. C. T. writes: 1. I have a water tank for supplying my boiler,which is made of No. 22 galvanized iron; size 30 inches by 9 feet 4inches. How many gallons will it hold? A. 342 gallons. 2. Will it bebetter to have it painted inside? A. Yes. 3. How many years will thetank wear under favorable circumstances, using well water? A.Depends upon the care taken of it.

(9) W. H. C. asks: Is there any way of deadening the noise ofmachinery overhead from the engine room below? The noise comes frommachinery in the weave room of an alpaca mill. A. This is generallyaccomplished by setting the legs of the machines on thick pieces ofIndia-rubber or other non-conductor of sound.

(10) G. H. asks: How can I mount photos on glass and color them? A.Take a strongly printed photograph on paper, and saturate it fromthe back with a rag dipped in castor oil. Carefully rub off allexcess from the surface after obtaining thorough transparency. Takea piece of glass an inch larger all round than the print, pour uponit dilute gelatin, and then "squeegee" the print and glass together.Allow it to dry, and then work in artists' oil colors from the backuntil you get the proper effect from the front. Both landscapes andportraits can be effectively colored by the above method without anygreat skill being required.

(11) C. W. S. asks: 1. Is there any practical and effective methodknown for cutting screws by connecting the slide rest with themandrel of the lathe by gears or otherwise? A. This can be done inthis way: attach a spur wheel to the back of the face plate. Mount asimilar wheel on a short hollow shaft, and support the shaft by anarm bolted to the lathe bed so that the two spur wheels will meshtogether. Fit right and left hand leading screws to the hollow shaftof the second spur wheel, and drill a hole through them as well asthrough the hollow shaft to receive the fastening pin. Now removethe longitudinal feed screw of the slide rest and attach to one sideof the carriage an adjustable socket for receiving nuts filled tothe leading screws. The number of leading screws required willdepend of course on the variety of threads it is desired to cutunless a change of gear is provided. 2. A writer in a foreignjournal claims to make slides, or V-shaped pieces for slide rests,eccentric chucks, etc., on his lathe. Is any such process knownhere, or any process within the capabilities of an amateur mechanicby which the planing machine can be dispensed with? A. For smallwork held between the lathe centers a milling device fitted to theslide rest in place of the tool post will answer an excellentpurpose. This device consists of a mandrel carrying at one end thecutter and at the other end a large pulley. This mandrel isjournaled in a hinged frame supported by a block replacing the toolpost, and is adjusted as to height by a screw passing through an armprojecting from the supporting block. The direction of the belt isadapted to this device by means of pulleys.

(12) J. E. B. asks: 1. What is the best turbine water wheel now inuse? A. There are several wheels in market that seem equally good.You should examine all of them and decide from your own observationwhich is best. 2. What is the rule for finding the horse power ofwater acting through a turbine wheel which utilizes 80 per cent ofthe water? A. Finding the weight of water falling over the dam andits velocity in feet per minute, multiply the weight in pounds bythe velocity, and the result is foot pounds, divided by 33,000, thequotient is theoretical horse power; if your wheel gives out 80 percent. then 80 per cent of that result is the horse power of thewheel. 3. How can I calculate the capacity of a belt? A. You willfind an exhaustive article on the subject of belts on pp. 101, 102,Vol. 42,Scientific American, which contains the information youdesire. 4. What machine now in use is the best, all thingsconsidered, for the manufacture of ground wood pulp? Where are theymanufactured? A. This information can probably be obtained byinserting an advertisement in the Business and Personal column ofthis paper.

(13) C. A. R writes: Wishing to renew my Leclanche batteries, whichwere giving out, I bought some new empty porous cells. Please givethe following information: 1. Can I use the carbon plates of the oldelements over again? If so, do they need to undergo any washing orsoaking; or are they as good as ever? A. Yes. Soak them for a fewhours in warm water. 2. Is there anything I must add to the granularmanganese with which I fill the cells, in order to obtain maximumpower and endurance? Some makers add pulverized or even coarselybroken carbon. Is it an advantage? A. It is an advantage to addgranulated carbon to the manganese. Use equal parts of each. 3. Whatis the exact composition of the curdy mass which forms around andespecially underneath the zincs of newly mounted and old gravitybatteries. Is this substance formed naturally, or is it the resultof using poor zinc or sulphate of copper? A. It is copper, andshould be removed, for it weakens the battery. It is the result ofplacing the zinc in the sulphate of copper solution. 4. Is there anyreal advantage in amalgamating the zincs of the above batteries? A.No. 5. Is there a speedy way of cleaning them when coated with thissubstance? A. They can be cleaned by scraping. 6. At certainoccasions my electric bells began ringing without anybody apparentlyclosing the circuit. I often notice that if I unjoin the batteriesand let them remain thus for a few hours, on reconnecting them thebells would work all right for a week, sometimes a fortnight, whenthe same trouble would again occur. Can you in any way explain thisphenomenon? The batteries are not placed in a very dry part of thehouse, but the wires, which run pretty closely together, are nearlyall exposed, so that I can control the slightest corrosion oruncovering of the conductors. A. There must be some accidentalclosing of the circuit. We could not explain the action of your linewithout seeing it.

(14) J. E. E. asks: What is the number of layers of wire, and thesize used for the primary of the induction coil in the Blaketransmitter, and as near as you can the amount used for secondary?A. For primary, use three layers of No. 20 magnet wire, and for thesecondary use twelve or fourteen layers of No. 36 silk coveredcopper wire. The resistance of the secondary wire should be from 100to 150 ohms.

(15) J. M. I. asks how to make a barometer by coloring ribbon, sothat they will change color, indicating weather changes. A. Use amoderately strong solution of chloride of cobalt in water.

(16) O. C. H. writes: In reply to R. A. R., question 22, inScientific American, December 4, I will say that some months ago Iwas engaged in running a saw mill, lathe, and shingle factory; wastroubled with two hot boxes, and frequently had to stop and applyice. Seeing in theScientific American a reference to the use ofplumbago, I sent for some, and after three or four applications wastroubled no more with hot boxes.

(17) F. W. asks: What is the best way for return pipe to go intothe boiler from radiators—steam at 60 lb. per square inch, fall 15feet? A. If your job is properly piped you can bring your returnpipe in at any convenient place in your boiler below the water line.If you go into the feed pipe, have your connection inside all othervalves.

(18) L. T. G. writes: 1. I have four cells of carbon battery; thesolutions are bichromate of potash and sulphuric acid. Also threecells of the Smee; sulphuric acid one part, to ten of water; and thefour cells of the carbon battery are not sufficient to run my smallelectro-magnetic engine, for more than two or three minutes. I wishto know if it would be injurious to either one of the batteries if Ishould unite them both in one circuit, to run the engine, for aboutone or two hours at a time. A. The batteries will not be injured,but they will not work well together. Better increase the number ofcarbon elements. 2. Will either of the above batteries freeze inwinter, or will cold weather affect their working? A. They will notfreeze, but it is better to keep them at a temperature abovefreezing 3. Is it always best to use the largest wire in connectingbatteries with any instrument, say, above No. 11 or No. 12 wire, asthe larger the wire the less the resistance, thereby getting nearlythe full power of the battery? A. Yes. 4. What purposes are quantityand intensity electricity best suited for respectively? A. Batteriesare arranged for quantity or intensity according to the work to bedone. The maximum effect is obtained when the battery elements arecombined, so that the total resistance in the elements is equal tothe resistance of the rest of the circuit.

(19) J. H. asks: Which would be the strongest, two 2-inch by 4-inchjoists nailed together, or one 4-inch by 4-inch joist? A. One 4-inchby 4-inch.

(20) J. K. B. writes: I suppose every experimenter who uses a carbonbattery has been troubled by the uncertainty of the carbonconnection. The makers of the Grenet battery seem to have solved theproblem. Can you tell us through your correspondence column whatsolder they use, and how they make it stick? A. The carbon is coatedwith copper by electro-deposition; this coating is readily solderedto the carbon support with common soft solder.

(21) M. D. M. asks: 1. Is there a difference in a steam enginebetween the boiler pressure and the pressure on the piston when thepiston is moving 460 feet per minute? A. Yes. 2. About whatdifference? A. From 2 to 8 lb., depending upon size and length ofsteam pipe. 3. Does the difference between them vary with adifference in the motion of the piston in the same engine? A. Notappreciably within usual limits of speed.

(22) F. writes: We have just closed up our steam stone works forthis season, and we wish to know what is best to coat the inside ofour steam boilers to keep them from rusting. Some say black oil, andothers common tallow: which do you recommend as the best? A. Wethink the black oil quite as good and cheaper than tallow. Have thesurfaces thoroughly cleaned before applying the oil.

(23) O. H. asks for a cheap and easy way of amalgamating batteryzincs. A. It depends on the kind of battery. In the Fuller themercury is placed in the porous cell with the zinc. In bichromatebatteries all that is necessary is to dip the zinc in the bichromatesolution and then pour on a drop or two of mercury. It soon spreadsover the entire surface of the zinc. Another method is to dip thezincs in dilute sulphuric acid and then pour on a little mercury,but these methods, except in the case of the Fuller battery, arewasteful of mercury. It is better to apply an amalgamating solutionwith a brush. This solution is made by dissolving one part (byweight) of mercury in five parts of nitro-muriatic acid (nitric acidone part, muriatic acid three parts), heating the solutionmoderately to quicken the action; and, after complete solution, addfive parts more of nitro-muriatic acid.

(24) G. W. asks: 1. Would a perfectly round ball of the samespecific gravity throughout lie still on a level surface? A. Yes. 2.Can a mechanic's square be made so true that a four-inch block maybe made exactly square by such an instrument? A. Yes.

(25) W. H. asks: 1. What is the weight of a boiler 24 feet long, 44inches diameter, ¼ inch thick? A. With two flues, 16 inchesdiameter, 6,900 lb. 2. What is the contents (in gallons) of a tank15 feet deep, 10 feet in diameter, top and bottom diameters beingequal? Please give me a formula. A. Area of 10 feet diameter = 78.54x 15 feet deep = 1,178 cubic feet, and, allowing 7½ gallons percubic foot = 1,178 x 7.5 = 8,835 gallons.

(26) C. L. W. writes: I have constructed a small induction coil tobe used for giving shocks. It is 3 inches long. The primary coil iswound with 3 layers of No. 18 cotton covered wire, and the secondaryconsists of about 12 layers of No. 38 silk covered. 1. How manycells and what kind of battery shall I use to get the best results?A. For temporary use one cell of Grenet battery would answer, butfor continued use some form of sulphate of copper battery is to bepreferred. 2. Is it necessary that the spring and screw in theinterrupter should be coated with platinum? A. Yes; otherwise theywould soon burn out.

(27) H. C. P. writes: In theScientific American of September 18,Mr. B. Y. D., query 26, asks whether a sun dial, made for latitude48° 15', can be utilized in latitude 38° 50' for showing correcttime. To make his dial available in the lower latitudes, he has onlyto lift the south side, so as to give the face a slope to the north,equal to the difference of the latitude, in this case 9° 25'. Forthen the plane of the gnomon being in the plane of the meridian, theedge of the gnomon casting the shadow will be parallel with theearth's axis; and the face of the dial will be parallel with thehorizon of the latitude for which the dial was made, and thegraduation will show the time required; that is, on the suppositionthat it was correctly made, and for a horizontal dial.

(28) O. M. M. asks for a cheap process of plating steel case kniveswith tin. A. Clean the metal thoroughly by boiling in strong potashwater, rinsing, pickling in dilute sulphuric acid, and scouring witha stiff brush and fine sand. Pass through strong aqueous salammoniacsolution, then plunge in hot oil (palm or tallow). When thoroughlyheated remove and dip in a pot of fused tin (grain tin) covered withtallow. When tinned, drain in oil pot and rub with a bunch of hemp.Clean and polish in hot sawdust.

(29) V. R. P. writes: I have an aquarium which contains 4-2/3gallons of water. How many fish must I have in it—average length offish 1½ to 2 inches to insure the health of the fish? At present, Irefill the aquarium semi-weekly. Please tell me a process by which Ican lengthen the time. A. Put in three fish, 1½ inches in length, toone gallon of water, one small bunch of fresh water plants to onegallon of water. Tadpoles (after they have cast their branchia orgills), newts, and rock fish can be used to the extent of six to thegallon. The aquatic plants will supply the fish with sufficientoxygen, so that the water will seldom require changing.

(30) A. S. writes: I am about to construct an aqueduct 1,200 feet inlength, the water level differing 40 feet. By placing a forcing pumpin the valley I could then raise the water to a height of 40 feet,and having erected a tank at that height and connected it by meansof pipes with another tank 1,200 feet distant, but on the samelevel, the water according to a law of nature would travel over thedistance of 1,200 feet. But finding it very difficult to erect tank40 feet high, I would prefer to construct the whole on the incline.Will the forcing pump having just power enough to raise the water 40feet perpendicularly into the tank have sufficient power to force itinto a tank of the same elevation through 1,200 feet of pipe runningon the incline, or must I have more power, and how much more? A. Theforcing pump must have enough more power to overcome its ownadditional friction and the friction of water in the long inclinedpipe. Allow 20 per cent more power at least.

Minerals, Etc.—Specimens have been received from the followingcorrespondents, and examined, with the results stated:

Box marked C. H. (no letter.)—1. and 2. Garnetiferous quartz rock.3 and 4. Micaceous quartz rock. 5. Granite. 6. Basalt with traces ofchalcopyrite.—L. C. G.—They are fossil sharks' teeth, common inmarl beds.—J. E. C.—1. Iron sulphide and lead sulphide. 2.Quartzite, with traces of galena and molybdic sulphide. 3 and 4.Dolomite. 5. Fossiliferous argillaceous limestone, containing tracesof lead sulphide. 6. Lead sulphide in argillite.—C. T. M.—1. Asilicious kaolin. 2. Similar to No. 1. Useful if mixed with finerclay for white ware. 3. Silicions carbonate of lime—some of thiswould probably make fair cement. 4. Brick—the clay from which thiswas made would probably be useful to potters. 5 and 6 are verysilicious clays.

COMMUNICATIONS RECEIVED.

INDEX OF INVENTIONS

Letters Patent of the United States were Granted in the Week Ending:

November 16, 1880,

AND EACH BEARING THAT DATE.

A printed copy of the specification and drawing of any patent in theannexed list, also of any patent issued since 1866, will befurnished from this office for one dollar. In ordering please statethe number and date of the patent desired and remit to Munn & Co.,37 Park Row, New York city. We also furnish copies of patentsgranted prior to 1866; but at increased cost, as the specificationsnot being printed, must be copied by hand.

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TOOPE'S PAT. FELT AND ASBESTOS

as manufactured by Toope's Asbestos Covering Co.,Limited, London, England. Awarded a Medal of Excellenceat the late American Institute Fair. For steamBoilers and Pipes, Steam Pans and Coppers, Hot andCold Water Pipes, Refrigerators, Meat Cars, etc. Samplesfree. A few first-class agents wanted. AddressCHS. TOOPE, Sole Manufacturing Agent in U. S. Officeand Works, 353 East 78th Street, New York City.

FOR SALE-LARGE MACHINE SHOP, WITHMachinery, Tools, Engine, etc.,ready for running.Inquire of A. MONNETT & CO., Bucyrus, Ohio.

50 A Elegant, All New, Chromo & Scroll Cards, no 2 alike,Name Nicely printed, 10c. Card Mills, Morthford, Ct.

PATENT BENDING ROLLS,

HILLES & JONES, Wilmington, Del.

Oline Lubricating Compound, manuf'd by HOLLAND& THOMPSON, Troy, N. Y. Avoids hot journals, dripping,and waste. Send for catalogue of Grease and Cupsfor all kinds of machinery.

PLAYS! PLAYS! PLAYS! PLAYS!

For Reading Clubs, for Amateur Theatricals, TemperancePlays, Drawing Room Plays, Fairy Plays, EthiopianPlays, Guide Books, Speakers, Pantomimes, TableauxLights, Magnesium Lights, Colored Fire, BurntCork, Theatrical Face Preparations, Jarley's WaxWorks, Wigs, Beards, and Moustaches at reducedprices. Costumes, Scenery, Charades. New cataloguessent free containing full description and prices.

ICE AND ICE HOUSES—HOW TO MAKEice ponds; amount of ice required, etc., and full directionsfor building ice-house, with illustrated plan. ContainedinScientific American Supplement, No. 55.Price 10 cents. To be had at this office and of all newsdealers.

THE NEW TOY!

Mechanical grasshopper, jumps6 feet high. Samples free for 10cents, 4 for 25 cents, 1 doz. for 50cts.By mail. Big Profit to Dealers.

ValuableCatalogue of Agents Goodsfree. Address, WORLD M'F'G,CO. 122 Nassau St., New York.

50 CHROMOS, name in new type,10c. by mail.40 Agts. Samples, 10c.U. S. Card Co., Northford, Ct.

WANTED, BY THE SOUTHWARK FOUNDRY ANDMACHINE CO., Philadelphia, a number of first-classfitters on engine work.

ICE-HOUSE AND COLD ROOM.—BY R.G. Hatfield. With directions for construction. Fourengravings. Contained inScientific American Supplement,59. Price 10 cents. To be had at this officeand of all newsdealers.

For Sale.—Engine for Steam Launch,

at a bargain. Cylinder, 4-1/2 in. diameter, 5 in. stroke.For particulars, address JAMES T. MILLER, 119 Monroe St., Chicago, Ill.

SCIENTIFIC AMERICAN SUPPLEMENT.Any desired back number of theScientific AmericanSupplement can be had at this office for10 cents. Also to be had of newsdealers in all parts ofthe country.

THE OPEN FIREPLACE IN ALL AGES.

With 269 illustrations of famous fireplaces of historicaland artistic interest, together with original designsand suggestions for modern use.

^*_*^* For sale by all Booksellers, or will be sent, postpaid, onreceipt of price, by the Publishers,

JAMES R. OSGOOD & CO., BOSTON.

STEAM PUMPS,THE NORWALK IRON WORKS CO.,SOUTH NORWALK, CONN.

CRUSHING AND GRINDING

GOLD and SILVER ORES, BONES, PHOSPHATEROCK, and CHEMICALS. We compelQUARTZ to grind QUARTZ.

Back geared and screw cutting. SmallLathes, Hand Planers for Metal, SmallGear cutters, Slide Rests, Scroll andCircular Saw Machines.Lowest Prices.Send for illustrated catalogue.

MECHANIC WANTED.

A skilled mechanic, capable of constructing and operatinga works for the manufacture of wrought iron pipeand tubing. Address

CENTENNIAL, AND PARIS MEDALS.

Mason's Friction Clutches and Elevators.

WANTED

A thoroughly competent and experienced man to takecharge of a foundry employing 200 men, doing engineand general work. Address A. & Co., Box 773, New York.

BLAKE'S PATENT POSITIVE STEAM TRAP.

This Trap is adapted to allplaces where steam is used forheating ordrying purposes.It is simple in construction,positive in its working andmuch lower in price than anyother Trap.

Descriptive Circular sent onapplication. AddressSALAMANDER GRATE BAR CO,110 Liberty Street, New York.

THE PERFECTED STYLOGRAFIC

The most convenient and economical outfit for writing. Pen, Pencil, and Inkstand in one. Writes 50 large pageswithout refilling. Lasts a lifetime. Attaches to watch chain or neck cord, or fits vest pocket. Price $2.50. Canbe ordered by mail, and exchanged or returned if not suited. For full description of various styles, send forcircular.

READERS' AND WRITERS' ECONOMY CO.,
25-33 Franklin Street, Boston; 4 Bond Street, New York; 38 Madison Street, Chicago.

Phosphor-BronzeWire, Sheets, Rods, Bolts.

Pamphlets and particulars on application toThe Phosphor-Bronze Smelting Co. Limited,2038 Washington Ave., Phila., Pa.

THE MAGICAL ORGANETTE, ONLY $8.00.

Double size Reeds, extra strength and finish.
Circulars and beautiful Set Fancy Cards, 8 Cents.

PERKINS'
High Pressure Engine and Boiler, Etc.

On returning to England, I have arranged withMr.James L. Howard, ofHartford, Conn., to representthe interests ofThe Perkins' Engine Company,Limited, of London, in this country. All communicationsaddressed to him on this subject will receiveattention.

50LithographedChromo Cards, no 2 alike,10c.Name in fancy type.Conn. Card Co., Northford, Ct.

DO YOUR OWN PRINTING

Presses and outfits from $3 to $500Over 2,000 styles of type. Catalogue andreduced price list free.

H. HOOVER, Phila., Pa.

STRAUSS'SLAST. THE HEKTOGRAPH SCHNELL POLKApronounced by critics as unrivalled, the rageat balls and parties, sent on receipt of 15 cts.Hektograph Co. Pub's, 22 Church St., N. Y.

TOOPE'S PATENT FURNACE GRATE BAR.Best and cheapest in the world. CHS. TOOPE, ManufacturingAgent, 353 East 78th Street, New York.

Wanted Manufactured on royalty, a valuable patentedtwo-horse Corn Planter. Box 1525, Terre Haute, Ind.

Pond's Tools,

Engine Lathes, Planers, Drills, &c.

DAVID W. POND, Worcester, Mass.

THE GREAT WORK, splendidly illustrated with coloredplates, now ready. It sells at sight. Agents wanted. Sendfor particulars. Rich Masonic goods, Kt. Templar outfits,and books at hard-pan prices. Send for illustrated catalogue.REDDING & CO., Masonic Publishers, 731 Broadway,New York. Beware of spurious works.

SPARE THE CROTON AND SAVE THE COST.

Driven or Tube Wells

furnished to large consumers of Croton and RidgewoodWater. WM. D. ANDREWS & BRO., 235 Broadway. N. Y.,who control the patent for Green's American Driven Well.

WOOD WORKING

Machinery. Celebrated "Schenck" Planers and Matchers.20,000 ft. flooring, 45,000 ft. surfacing per day. Re-sawers,Moulders, Tenoners, Scroll Saws, etc. H. B. Schenck,Successor to Jno. B. Schenck's Sons, Matteawan, N. Y.

"The 1876 Injector."

Simple, Durable, and Reliable. Requires no specialvalves. Send for illustrated circular.

Shafts, Pulleys, Hangers, Etc.

SOAP AND CANDLES,STARCH, DEXTRINE, and GLUCOSE.IN PRESS.

A Technical Treatise on Soap and Candles, witha Glance at the Industry of Fats and Oils. By R. S.Cristiani. Fully illustrated. 500 pages 8vo, handsomelyprinted on fine paper.

A Practical Treatise on the Manufacture ofStarch, Dextrine, and Glucose. Illustrated byabout 75 engravings. 300 pages 8vo, handsomely printedon fine paper.

HENRY CAREY BAIRD & CO.,
Industrial Publishers, Booksellers, and Importers,
810 Walnut Street, Philadelphia.

WITHERBY, RUGG & RICHARDSON, Manufacturersof Patent Wood Working Machinery of every description.Facilities unsurpassed. Shop formerly occupiedby R. Ball & Co., Worcester, Mass. Send for Catalogue.

$72 A WEEK. $12 a day at home easily made. Costlyoutfit free. AddressTrue & Co., Augusta, Me.

Superior Wood Working Machinery, principally for Cabinet,Piano, and Piano Action Makers. Shafting, Pulleys,and Hangers. P. Pryibil, 461 to 467 W. 40th St., New York.

SURFACE FILE HOLDERS.

By their use a crooked file may be utilized as well as astraight one, andboth are made to do better execution infiling broad surfaces than has hitherto been possible.

No. 4 holds files 12 to 14 in. long. Price 75c. each.
No. 5 " " 14 to 16 in. " Price $1.00 each.

For sale by the trade generally. Manufactured only by the NICHOLSONFILE CO., Providence, R. I.

THE BIGGEST THING OUT. Illustrated book sent free. Address E. NASON& CO., 111 Nassau St., New York.

ORGANS $30 to $1,000; 2 to 32 Stops. Pianos $125 up. Paper free.AddressDaniel F. Beatty, Washington, N. J.

Leffel Water Wheels, With recent improvements.

THREE BEAUTIFUL GIFT BOOKS FOR THE HOLIDAYS.

"THE DORE BIBLE GALLERY."

Containing One Hundred of the choicest of Gustave Doré'sillustrations of the Bible, and a page of explanatory letter-pressfacing each engraving, together with a superb portrait of theartist.

"ATALA"

An American story, and one of the best efforts of the celebratedauthor. Superbly illustrated with numerous full pages of some of ourgrandest scenery, by Gustave Doré. Printed on heavy tinted paper,and richly bound.

"THE WANDERING JEW."

A series of twelve illustrations by Gustave Doré, picturing theweird and unearthly scenes of the legend, with explanatoryletter-press.

"Such books are educators in the highest sense of theterm."—Chicago Inter-Ocean.

"One of the most successful productions that have done honor to thepencil of Gustave Doré."—Providence Journal.

"Contains some of the most striking productions of Doré at amoderate cost."—N. Y. Tribune.

"We are very glad they have been put within the reach of themany."—Hartford Courant.

For sale by all Booksellers, or sent, postpaid, on receipt of price,by the Publishers.

SASH DOVETAILING MACHINE.

Planers, Moulding Machines, Mortisers and Borers, Tenoning Machines,Blind Rabbeting Machines; also, a large variety of other woodworking machines, manufactured by

TELEPHONE Works 1 mile. Price $4. Pat'd. Circulars free.Holcomb &Co., Mallet Creek, Ohio.

AGENTS WANTED TO INTRODUCE a new and novel Account Book to businessmen. A rich harvest to competent parties during the next threemonths. All particulars by return mail.

$5 to $20 per day at home. Samples worth $5 free. AddressStinson &Co., Portland, Me.

ERICSSON'S NEW MOTOR.

ERICSSON'S NEW CALORIC PUMPING ENGINE, FOR DWELLINGS AND COUNTRYSEATS.

Simplest cheapest, and most economical pumping engine for domesticpurposes. Any servant girl can operate. Absolutely safe. Send forcirculars and price lists.

DELAMATER IRON WORKS

THE BLAKE "LION AND EAGLE" CRUSHER,

A patented improvement of the former "New Pattern" Blake machine.Has much greater efficiency than the old. It requires only abouthalf the power to drive, and is transported at much less expense(the size most used weighing several thousand pounds less than theunimproved machine). It requires less than half the time in oilingand other manipulation, and less than half the expense for repairs.Address

W. C. WREN'S
Pat. Grate Bar,
Manufactured by
D. & S. CRESWELL,
EagleIron Foundry,
816 RACE ST.,
PHILADELPHIA, PA.

ROCK BREAKERS & ORE CRUSHERS.

This machine has for twenty years stood theTest, and found to bethebest one made for breaking all kinds of hard and brittlesubstances, such asOres,Quartz,Emery, etc., etc. Mr. S. L.Marsden, for the past twenty years connected with the manufacture ofthis machine, superintends its manufacture.

The Melodette, or Automatic Piano,

The most marvellous mechanical invention of the age. It will playany tune that ever was written, in a melodious and pleasing manner.Difficult and simple music produced in a masterly style, and it canbe played by a child as well as by a grown person, and will furnishmusic for social gatherings of any description, playing hour afterhour, without any knowledge of music being required in theoperation. The most wonderful of all musical inventions; a machinewhich in a purely mechanical manner produces any kind of music,Waltzes, Polkas, Marches, &c., &c., without any practice orknowledge of music whatever; in this respect far superior to anymusic-box, even though it costs many times as much, for there is nolimit whatever to the number of tunes it will play. This instrumentis on a somewhat similar principle to the wonderful Phonograph, theperforations in a flexible strip producing the effect. It has justbeen perfected (the accompanying cut showing it in its improvedform), and is having the largest sale ever obtained by a musicalinstrument in the country. It has solid metal cases in imitation ofgreen bronze; the notes or bars (the music producers) are metal, onsame principle as a tuning-fork, which produce clear and mostmelodious notes, and never get out of tune; the bars are struck bystrikers, the same as the wires are in a piano, only they workautomatically instead of by the fingers. The strip of prepared paperin which the tune is stamped or perforated, is about 10 inches wide,and as it passes through the rollers and over the keys the strikersspring through the perforations in the paper and strike the rightnote; this is all done automatically, without any assistance fromthe operator (except turning the rollers), and the tune is playedperfectly. It would be one of the most appropriate presents to makeanyone, especially where there is no other musical instrument. Itsexecution is admirable, and its capacity or capability almostunlimited. It is selling faster than any musical instrument everinvented. The music is fine, and everybody delighted. The regularretail price of the Melodette is only$5, including a selection ofpopular tunes. Address,The Massachusetts Organ Co., 57WashingtonStreet Boston, Mass., U. S. A., Sole Manufacturers. SPECIALOFFER—Agents Wanted—We wish a good Agent in every town, and bigmoney can be made selling these instruments. We will send a sampleinstrument to any one wishing to act as our agent, for$3.25,BoxedFree, including music price lists, etc., etc., and will giveterritory. Order at once. $50 a week easily made.We have 1000testimonials.

RUBBER BACK SQUARE PACKING.

B represents that part of the packing which, when in use, is incontact with the Piston Rod.

A the elastic back, which keeps the part B against the rod withsufficient pressure to be steam-tight, and yet creates but littlefriction.

This Packing is made in lengths of about 20 feet, and of all sizesfrom 1/4 to 2 inches square.

JOHN H. CHEEVER, Treas. NEW YORK BELTING & PACKING CO., 37 & 38 ParkRow, New York.

THE STEARNS MANUFACTURING CO.,

Designed in its construction for producing lumber economically andrapidly. Plans and estimates for Mills of any capacity furnished onrequest. Also build ENGINES, BOILERS, AND MACHINERY IN GENERAL.

Forster's Rock & Ore Breaker and Combined Crusher and Pulverizer.

Parties who have used it constantly for six years testify that itwill dodouble the work ofany other Crusher, with one-third thePower, and one-half the expense for keeping in repair. The smallersizes can be run with Horse Power.

The BELMONTYLE OIL

Prevents Rust, Tarnish, etc., on Firearms, Machinery, Tools,Cutlery, Safes, Saws, Skates, Stoves, Hardware, etc., without injuryto the polish. In use over 10 years. Highest Testimonials. Samples50 cents, three for $1.00, sent free of expressage. Send forcircular.

The attention of Architects, Engineers, and Builders is called tothe great decline in prices of wrought

It isbelieved that, were owners fully aware of the small difference incost which now exists between iron and wood, the former, in manycases, would be adopted, thereby savinginsurance and avoiding allrisk ofinterruption tobusiness in consequence of fire. Book ofdetailed information furnished to Architects, Engineers, andBuilders, on application.

MICROSCOPES,
TELESCOPES, FIELD GLASSES,
MAGIC LANTERNS,
ANEROID BAROMETERS,
SPECTROSCOPES,
DRAWING INSTRUMENTS,
PHILOSOPHICAL & CHEMICAL
APPARATUS.

Catalogues as follows sent on application: Part 1, MathematicalInstruments, 162 pp.; Part 2, Optical Instruments, 186 pp.; Part 3,Magic Lanterns, 112 pp.; Part 4, Philosophical and ChemicalApparatus, 160 pp.JAMES W. QUEEN & CO. 924 Chestnut St.,Philadelphia, Pa.

"RELIABLE"

Engines a complete success. Prices still 40 per cent. below those ofother makers. Unequaled for efficiency, simplicity, and durability.Prices from $250 for 10 H. P., to $400 for 30 H. P. All complete,with Governor, Pump, and Heater. Address, for circular,

UNIVERSAL GRINDER.

These Grinders consist of a series of disks with beveled edgeslocked together on a shaft. They revolve towards each other atdifferent rates of speed. They combine strength and durability. Nofriction; hence no heat. They will grind all kinds of Grain, alsoQuartz Rocks, Ores, Gypsum, Brimstone Shavings, Shells, Brick Clay,Cork, Rubber, Bone, Oil Cake, Flax Seed, Cotton Seed, and any numberof articles in use by manufacturers and farmers. These Grinders aredisposed of on reasonable terms. Send for Illustrated Catalogue withterms. NEWELL & CHAPIN, foot of West 19th Street, New York.

OTIS'

SAFETY HOISTING

Machinery.

JOHN R. WHITLEY & CO.

European Representatives of American Houses, with First-classAgents in the principal industrial and agricultural centers andcities in Europe. London, 7 Poultry, E. C. Paris. 8 Place Vendême.Terms on application. J. R. W. & Co. purchase Paris goods oncommission at shippers' discounts.

ROOTS' NEW IRON BLOWER.

POSITIVE BLAST.
IRON REVOLVERS, PERFECTLY BALANCED
IS SIMPLER, AND HAS
FEWER PARTS THAN ANY OTHER BLOWER.

PROPOSALS FOR MAIL LOCKS.

SEALED PROPOSALS will be received at this Department,until 12o'clock, noon, on the 26th day of January, 1881, for furnishing anew kind of mail locks and keys for the sole and exclusive use ofthe United States through registered mails.

As the public exposure and searching examination necessary tointelligent bidding on any prescribed model of a lock and key wouldtend to impair, if not entirely destroy, the further utility of suchlocks and keys for the purposes of the mails, the Postmaster Generalprescribes no model or sample for bidders, but relies for aselection on the mechanical skill and ingenuity which a faircompetition among inventors, hereby invited, may develop in samplessubmitted by them.

Specifications of the conditions and requirements relating toproposals, samples, contract, etc., as well as forms of proposal,will be furnished on application by letter to the Second AssistantPostmaster General.

No proposal will be considered unless it shall have been submittedin accordance with such specification and forms.

The contracts which may be made will be in conformity to thespecifications and the accepted proposal. But the right is, however,reserved to reject any and all of the proposals.

SHEPARD'S CELEBRATED
$50 Screw Cutting Foot Lathe.

Foot and Power Lathes, Drill Presses, Scrolls, Circular and BandSaws, Saw Attachments, Chucks, Mandrels, Twist Drills, Dogs,Calipers, etc. Send for catalogue of outfits for amateurs orartisans.

H. L. SHEPARD & CO.,
331, 333, 335, & 337 West Front Street,
Cincinnati, Ohio.

HUB MACHINERY.—HUB TURNING, HUB MORTISING, and Hub Boring Machines.Send for price list and circulars. DAVID JENKINS, Sheboygan, Wis.

ROOFING.

For steep or flat roofs. Applied by ordinary workmen at one-thirdthe cost of tin. Circulars and samples free. Agents Wanted. T. NEW,32 John Street, New York.

The fact that this shafting has 75 per cent. greater strength, afiner finish, and is truer to gauge, than any other in use rendersit undoubtedly the most economical. We are also the solemanufacturers of theCelebrated Collins' Pat. Coupling, and furnishPulleys, Hangers, etc., of the most approved styles. Price listmailed on application to

JONES & LAUGHLINS, Try Street, 2d and 3d Avenues, Pittsburg, Pa.
190 S. Canal Street, Chicago, Ill.

Stocks of this shafting in store and for sale by FULLER, DANA &FITZ, Boston, Mass. Geo. Place Machinery Agency, 121 Chambers St.,N. Y.

Model Engines.

for making small Model steam Engines 1-1/2in. bore, 3 in. stroke, price,$4; ditto 2 in. bore, 4 in. stroke,price, $10, same style as cut. Gear Wheels and Parts of Models. Allkinds of Small Tools and Materials. Catalogue Free. GOODNOW &WIGHTMAN, 176 Washington Street, Boston, Mass.

SEND FOR THE
BEST BAND SAW BLADE

MACHINISTS' TOOLS.

SKATES AND NOVELTIES.

PORTER MANUF'G CO.

The New Economizer, the only Agricultural Engine with Return FlueBoiler in use. Send for circular toPorter MFG. Co., Limited,Syracuse. N. Y.

Advertisements.

Engravings may head advertisements at the same rate per line, bymeasurement, as the letter press. Advertisements must be received atpublication office as early as Thursday morning to appear in nextissue.

The publishers of this paper guarantee to advertisers a circulationof not less than 50,000 copies every weekly issue.

THE WONDERFUL

CHRISTMAS "ST. NICHOLAS."

A special Holiday number, designed for boys and girls everywhere,whether regular readers of the magazine or not;—the best, and, byreason of its immense edition, 105,000, the cheapest Christmas bookpublished, Price 30 cents.

A brilliant Holiday cover; superb pictures by the best Americanartists; a capital acting operetta for children "The Land of Nod,"with words and music; a splendid story by Washington Gladden, "AChristmas Dinner with the Man in the Moon," the illustrations ofwhich rivalDore's; "King Arthur and his Knights," by Sidney Lanier;one of Frank R. Stockton's inimitable FAIRY STORIES; the "TreasureBox of Literature," etc., etc.;—in all, thirty-three departmentsand contributions.

A Grand Holiday Gift-Book of 100 Pages, printed on tinted paper,illustrated with scores of charming pictures, for only 30 cents. Askfor the Christmas (December)St. Nicholas. Four editions of lastyear's Holiday number were demanded. For sale everywhere.Subscription price, $3.00 per year.

$100 PRESENT!

This is the King of Saw Machines. It saws off a 2 foot log in 2minutes. 20,000 in use. The cheapest machine made, and fullywarranted. Circular free. United States Manufacturing Co., Chicago,Ill.

THE NEW YORK BELTING AND PACKING COMPANY

LOOK FOR OUR STAMP

BELTING, HOSE, OR PACKING.

Watchman's Improved Time Detector, with Safety Lock Attachment,Patented 1875-6-7. Beware of Infringements. This Instrument issupplied with 12 keys for 12 different stations. Invaluable for allconcerns employing night watchmen. Send for circulars to E.IMHAUSER, P. O. Box 2875. 212 Broadway, New York.

Mill Stones and Corn Mills.

We make Burr Millstones, Portable Mills, Smut Machines, Packers,Mill Picks, Water Wheels, Pulleys, and Gearing specially adapted toFlour Mills. Send for catalogue.

PULSOMETER

Is more economical in points of original cost,expense for repairs and running expenses, than any other Steam Pumpin the World.

Simple and compact, with no machinery whatever to oil, or get out oforder, it stands at the head of all means of elevating water orother liquids by steam.It needs no skilled labor to look afterit.

Send for book giving full description, reduced prices and manyletters of commendation from leading manufacturers and othersthroughout the country who are using them.

Pulsometer Steam Pump Co., Sole Owners of Hall's Patents in the U.S., 131,515 to 131,543, both inclusive, and theNEW PULSOMETER,Office, No. 83 John St., P.O. Box No. 1533. New York City.

Pictet Artificial Ice Co., Limited,

P.O. Box 3083 142 Greenwich St.,New York. Guaranteed to be the mostefficient andeconomical ofall existing Ice and Cold Air Machines.

H.W. JOHNS'
ASBESTOS

Steam Pipe & BoilerCoverings, Steam Packing, Mill Board, Sheathing, Fire ProofCoatings, &c.

$66 a week in your own town. Terms and $5 outfit free. AddressH.Hallett & Co., Portland, Me.

The George Place Machinery Agency

EMERY WHEELS and GRINDING MACHINES.

Orders may be directed to us at any of the following addresses, ateach of which we carry a stock:

HARTFORD
STEAM BOILER

COMPANY

COLUMBIA BICYCLE.

The Bicycle has proved itself to be a permanent, practical roadvehicle, and the number in daily use is rapidly increasing.Professional and business men, seekers after health or pleasure, alljoin in bearing witness to its merits. Send 3 cent stamp forcatalogue with price list and full information.

AGENTS
CAN MAKE $5,000.00

MANUFACTURERS' CABINET.

By employing Agents for 500 Manufacturers.
By manufacturing rapid selling articles.
By getting, through means of the Cabinet, the best agencies in the world.

Steam Fitters' & Plumbers' Supplies.

BOILER COVERINGS.

ASBESTOS MATERIALS.

Made from pure Italian Asbestos in fiber mill board and roundpacking. THE CHALMERS-SPENCE CO., 40 John Street, and Foot of E. 9thStreet, New York.

CUT THIN LUMBER!!

MAHOGANY,

Rosewood, Satinwood, Walnut, Ash, Red Cedar, Cherry, Oak,Poplar, Maple, Holly, French Walnut, etc., etc.. in Logs, Planks,Boards, and Veneers.

$55.66 Agents' profit per week. Will prove it or forfeit $500.00.Outfit and Samples worth $5.00 free. Address E. G. RIDEOUT & CO., 10Barclay Street, New York.

Steel Castings

From 1/4 to 15,000 lb. weight, true to pattern, of unequaledstrength, toughness, and durability. 15,000 Crank Shafts and 10,000Gear Wheels of this steel now running prove its superiority overother Steel Castings. Send for circular and price list.

Pyrometers.

For showing heat of Ovens, Hot Blast Pipes, Boiler Flues SuperheatedSteam, Oil Stills, etc.

WM. A. HARRIS
PROVIDENCE, R. J. (PARK STREET),

HARRIS-CORLISS ENGINE

"Good Design and Material. Very efficient in action. With thespecial advantages that they can be connected for motion directlywith engine without the use of gearing or belting."

WILBRAHAM BROS.

MICROSCOPES, OPERA GLASSES, SPY Glasses, Spectacles, Thermometers,Barometers, Compasses. R. & J. BECK, Manufacturing Opticians. Philadelphia, Pa. Send forIllustratedPriced Catalogue.

BOGARDUS' PATENT UNIVERSAL ECCENTRIC MILLS—For grinding Bones,Ores, Sand, Old Crucibles, Fire Clay, Guanos, Oil Cake, Feed, Corn,Corn and Cob, Tobacco, Snuff, Sugar, Salts, Roots, Spices, Coffee,Cocoanut, Flaxseed, Asbestos, Mica etc., and whatever cannot beground by other mills, Also for Paints, Printers' Inks, PasteBlacking, etc. JOHN W. THOMSON, successor to JAMES BOGARDUS, corner of White andElm Sts., New York.

New York Ice Machine Company,

ICE AND COLD AIR.

Low Pressure when running. No pressure at rest.Machines guaranteed by C. H. Delamater & Co.

Our new Stylographic Pen (just patented), having the duplexinterchangeable point section, is the very latest improvement. THESTYLOGRAPHIC PEN CO., Room 13, 169 Broadway, New York. Send forcircular.

KNABE

PIANOFORTES.

NON-CONDUCTOR COVERINGS,

FOR STEAM BOILERS AND PIPES.

POWER SHEARS.

DO YOUR OWN PRINTING $3 PRESS prints &c. (Self-inker $4) Larger sizes for larger work. Forold or young. Great money saver. A paying business anywhere for allor spare time. Send two stamps for a catalogue of all sizes.Presses, Type, Cards, Paper &c., to the Manufacturers KELSEY & CO.,Meriden, Conn.

The Asbestos Packing Co.,

BOSTON, MASS., OFFER FOR SALE:

PATENTED ASBESTOS ROPE PACKING,
PATENTED ASBESTOS LOOSE PACKING
PATENTED ASBESTOS JOURNAL PACKING
PATENTED ASBESTOS WICK PACKING
PATENTED ASBESTOS MILL BOARD,
PATENTED ASBESTOS SHEATHING PAPER,
PATENTED ASBESTOS FLOORING FELT,
PATENTED ASBESTOS CLOTH.

Scientific American

This widely circulated and splendidly illustrated paper is publishedweekly. Every number contains sixteen pages of useful information,and a large number of original engravings of new inventions anddiscoveries, representing Engineering Works, Steam Machinery, NewInventions, Novelties in Mechanics, Manufactures, Chemistry,Electricity, Telegraphy, Photography, Architecture, Agriculture,Horticulture, Natural History, etc.

All Classes of Readers find inThe Scientific American a popularresume of the best scientific information of the day; and it isthe aim of the publishers to present it in an attractive form,avoiding as much as possible abstruse terms. To every intelligentmind, this journal affords a constant supply of instructive reading.It is promotive of knowledge and progress in every community whereit circulates.

Terms of Subscription.—One copy ofThe Scientific American will besent forone year—52 numbers—postage prepaid, to any subscriberin the United States or Canada, on receipt of three dollars andtwenty cents by the publishers; six months, $1.60; three months,$1.00.

Clubs.—One extra copy ofThe Scientific American will be suppliedgratisfor every club of five subscribers at $3.20 each;additional copies at same proportionate rate.

One copy ofThe Scientific American and one copy ofThe ScientificAmerican Supplement will be sent for one year, postage prepaid, toany subscriber in the United States or Canada, on receipt of sevendollars by the publishers.

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Air engine, new	385
Amateur mechanics*	390
American Institute of Architects	389
Architects, American Institute	389
Arctic winter, characteristics of	393
Aquarium (29)	395
Balance attach. for valves*	386
Band saw, hand power*	387
Barometer, chemical (15)	394
Battery, Leclanche, to renew (13)	394
Beetle, Hercules, the*	391
Belts, capacity of (12)	394
Business colleges*	383, 388
Carbons, to solder (20)	395
Chinese women's feet*	393
Chisels, tempering	389
Colleges, business*	383, 388
Engine, air, new	385
Engine, steam, single-acting*	390
Eruption of Mauna Loa	385
Exhibition of bathing appliances	393
Feet, Chinese women's*	393
Fires—causes and prevention	384
Glass spinning and weaving	385
Gun, submarine, new	387
Harbor at Montreal, the	387
Hercules beetle, the*	391
Horse-power of turbines (12)	394
Ice at high temperatures	393
Ice, removing from railroads*	387
Induction coil for transmitter (14)	394
Induction coil, small (26)	395
Invention, schools of	393
Inventions, miscellaneous	390
Inventions, recent	387
Knots, learning to tie	392
Leaves, variegation of	392
Light, what is?	384
London underground railway	389
Mantis, the embrace of the	391
Mechanics, amateur*	390
Montreal, the harbor at	387
Noise, to deaden (9)	394
Nut, safety, improved*	386
Packard's Business College*	383, 388
Patents, decisions relating to	393
Petroleum prospects	386
Photos, to color (10)	394
Poultry raising, mechanical	391
Railway, underground, London	389
Safety nut, improved*	386
Safety valve, improved*	386
Schools of invention	393
Screw-cutting foot lathe (11)	394
Steamers, Collins line of	393
Steam heating, return pipe (17)	394
Steel, to tin (28)	395
Submarine gun, new	387
Sun dial, to adjust (27)	395
Telegraph insulator, new*	387
Telegraph wires underground	385
Valve, safety, improved*	386
Valves, balance attachment for*	386
Vanilla, cinnamon, cocoanut	392
Vennor's winter predictions	389
Vessels, sunken, raising	386
Winter predictions, Vennor's	389
Zinc, to amalgamate (23)	395

FIRST DEPARTMENT	FOURTH OR FINISHING DEPARTMENT
SECOND DEPARTMENT	THE BUDGET ROOM
THIRD DEPARTMENT	THE ASSEMBLY ROOM

One copy, one year postage included	$3 20
One copy, six months, postage included	1 60

		page
I.	ENGINEERING AND MECHANICS.—Frager's Water Meter. 3 figures.—Vertical section, horizontal section, and plan	4119
	Transmission of Power to a Distance.—Wire ropes—Compressed air—Water pressure.—Electricity	4120
	The Livadia at Sea	4120
	The Herreshoff Launch	4121
	New Steering Gear. 2 figures.—Steam steering gear for Herreshoff launch	4121

II.	TECHNOLOGY AND CHEMISTRY.—Glucose	4126
	American Manufacture of Corn Glucose	4126
	The Conversions—Starch—Dextrine.—Complete glucose	4126
	Depreciation of a Glucose Factory	4126
	The Fire Risks of Glucose Factories and Manufactures	4126
	Glucose Factory Fires and Ignitions	4127
	The Hirsh Process. ByAdolf H. Hirsh—Improvement in the manufacture of sugar from Corn	4127
	Time in the Formation of salts. ByM. Berthelot	4127
	An Old Can of Preserved Meat ByG. W. Wigner	4127
	Chemistry for Amateurs. 6 figures.—Reaction between nitric acid and iron.—Experiment with Pharaoh's serpents.—Formation of crystals of iodide of cyanogen—Experiment with ammoniacal amalgam.—Pyrophorus burning in contact with the air.—Gold leaf suspended over mercury	4128
	Carbonic Acid in the Atmosphere. 2 figures	4129
	On Potash Fulling Soaps ByW. J. Menzies	4129
	Photography of the Invisible	4134

III.	ELECTRICITY. LIGHT, HEAT, ETC.—Exhibition of Gas and Electric Light Apparatus, Glasgow	4125
	Electric Light in the German Navy. 1 illustration. Armored Frigates Friedrich Karl and Sachsen.—Dispatch Boat Grille, and Torpedo Boat illuminated by Electric Light	4130
	Interesting Facts about Gas and Electricity.—Gas as Fuel.—Gas for Fire Grates	4130
	A New Electric Motor and its Applications. 6 figures. Trouve's New Electric Motor	4131
	On Heat and Light. ByRobert Ward	4131
	Photophonic Experiments of Prof. Bell and Mr. Tainter. ByA. Bregult	4132
	Distribution of Light in the Solar Spectrum. ByJ. Mace andW. Nicati	4132
	Mounting Microscopic Objects	4132
	New Sun Dial. ByM. Grootten. 1 figure	4132
	Antoine Cesar Becquerel, with portrait	4132

IV.	HYGIENE AND MEDICINE.—On the Etiology of the Carbuncular Disease. ByL. Pasteur, assisted byChamberland andRoux. An extremely valuable investigation of the nature, causes, and conditions of animal plagues	4133
	Report on Yellow Fever in the U. S. Steamer Plymouth. By the Surgeon-General in U. S. Navy	4134
	Fuchsin in Bright's Disease	4134

V.	ART, ARCHITECTURE, ETC.—Artists' Homes. No. 7. Sir Frederick Leighton's House and Studio. 10 figures. Perspective, plan, elevation details, etc.	4121
	Initials by Eisenlohr and Weigle, in Stuttgart. Full page	4123
	Suggestions in Decorative Art. 1 figure. Reserved part of a Great Saloon. ByH. Penox, Paris	4124
	Great Saloon (Text)	4124
	Cologne Cathedral The Historical Procession	4124
	Suggestions in Decorative Art. 1 figure. Mantlepiece in Walnut. ByE. Carpenter	4125

Coffin screw, E. A. Cuppers	12,033
Gem setting, Vennin & Peltier	12,037
Lamp bracket, F. R. Seidensticker	12,036
Stove, cooking, H. L. Fennell	12,034
Type, font of printing, J. K. Rogers	12,035

Alloy for coating metals, J. B. Jones	234,482
Axle box, car, H. Hazel	234,568
Bag holder and truck therefor, L. H. Aldrich	234,381
Baling press, W. Duke	234,549
Band cutting and removing apparatus. W. Gray	234,561
Basket splints, machine for shaving, A. B. Fisher	234,398
Belt shifting mechanism for washing machines, L. Sternberger	234,439
Belt shipper, B. H. Hadley	234,563
Bias cutter, W. F. Hood	234,476
Bit brace, N. Spofford	234,624
Bit stock, Q. S. Backus	234,517
Book case, M. C. Dodge	234,461
Book holder, W. B. Daugherty	234,460
Boot and shoe heel, J. G. Ross	234,430
Boot and shoe soles, machine for forming imitation fair stitches to the edges of, Tayman & Bennor	234,503
Boot treeing machine, E. F. Grandy	234,401
Borer and excavotor, earth, J. W. Carley	234,532
Bottle wrapper, M. V. Kacer	234,582
Bridle front, B. A. Wilson	234,445
Buckle, D. C. Bassett	234,453
Buckle, harness, B. H. Cross	234,394
Butter worker, Cornish & Curtis	234,459
Button and stud, N. Nelson	234,604
Buttonhole for cuffs, etc., C. H. Shaw	234,620
Can, E. P. Fox	234,465
Can opener, W. E. Brock	234,527
Car brake, G. Bressler	234,525
Car brake, C. V. Rote	234,493
Car brake, G. A. Small	234,622
Car coupling, W. I. Ely	234,550
Car door fastener, Briggs & Dougherty	234,526
Car, railway, G. L. Waitt	234,507
Car starter, J. Ladner	234,590
Car, stock, W. Neracher	234,420
Car wheel, E. L. Taylor	234,502
Cars, shield for railway Mason & Hanson	234,416
Caster, trunk, J. Simmons	234,496
Chain, J. M. Dodge	234,548
Chains, device for making, H. Wexel	234,444
Chair, W. R. Clough	234,537
Chandelier, extension, T. D. Hotchkiss	234,477
Cheese curd sifter and picker, F. M. Cummings	234,543
Churn, M. F. Mitchel	234,418
Clock, traveling, H. Reinecke	234,612
Clock winding and gas cock mechanism, combined, G. P. Ganster	234,557
Clothes wringer, S. Huffman	234,577
Coal fork, T. R. Way	234,633
Coin, device for holding, counting, and delivering, Van Slyke & Nesom	234,441
Collar and cuff folding machine, M. Hermann	234,571
Confectioners' forms and their application, W. E. H. Sommer	234,623
Corn husks, apparatus for cutting, W. A. Wright	234,640
Corn husks, disintegrating, W. A. Wright	234,641
Corset, C. F. Allen	234,380
Cotton picker, G. Risler	234,613
Cotton press, S. Stucky	234,626
Cradle and carriage, combined, G. F. Doyle	234,547
Crank movements, apparatus for overcoming the dead point in, P. E. Jay	234,496
Crimping pin, C. D. Thompson	234,629
Cuff fastener and supporter, A. B. Case	234,533
Cultivator and seeder, combined, J. D. Chichester	234,390
Current and tide water wheel, H. Fake	234,396
Currycomb, M. Sweet	234,501
Curtain fixture, H. Seehausen	234,495
Draught equalizer, F. H. Sandefer	234 625
Drawer lock, G. E. Bendix	234,454
Drilling machine, T. Naish	234,603
Drip pan for oil barrels, C. E. Laverty	234,411
Electric light burner, J. Sarcia	234,618
Electric lights or motors, automatic cut-out apparatus for, C. F. Brush	234,456
Electric machines, rotating armature for dynamo, E. Weston	234,443
Electrical switch board, J. W. See	234,432
Embroidering machines, jacquard attachment for, M. Umstadter (r)	9,470, 9,471
End board, wagon, H. A. Riggs	234,614
Excelsior machine, C. Howes	234,475
Explosive compound, C. A. Morse	234,489
Eyeglasses, R. Kabus	234,581
Faucet attachment, C. A. Raggio	234,429
Feed bag, T. R. Lowerre	234,593
Fence post, wire, Ticknor & Bebee	234,440
Ferric oxide and cupric chloride, manufacture of, J. F. N. Macay	234,595
Filter, coffee and tea, T. Fitzgerald, Jr.	234,556
Filter, reversible, R. S. Jennings	234,408
Firearm, breech-loading, J. L. Volkel	234,632
Fire escape, Quintavalle & Lindberg	234,611
Fires, process of and apparatus for extinguishing, J. H. Campbell	234,531
Foot, artificial, A. A. Marks	234,596
Fruit drier, G. P. & L. J. Lee	234,412
Fuel burning apparatus, J. Wolstenholme	234,448
Galvanic battery, G. L. Leclanché	234,413
Gas making apparatus, C. F. Dieterich	234,546
Gas pressure regulator, P. Noyes	234,421
Gas, process of and apparatus for manufacturing illuminating, Granger & Collins, Jr.	234,400
Gate, L. P. Allen	234,515
Gate, D. B. Hamilton	234,471
Gate, K. A. Scott	234,619
Gears, machine for cutting the teeth of metal, W. Gleason (r)	9,468
Gears, machine for cutting the teeth of wooden, W. Gleason (r)	9,469
Glassware, mould for pressed, W. Haley	234,564
Glove, R. D. Burr	234,528
Grain binder, C. B. Withington	234,638
Harness, C. E. Berry	234,519
Harness, suspending swinging, C. E. Berry	234,520
Harrow, W. H. Hulings	234,576
Harrow and cultivator tooth, G. C. Winslow	234,639
Hat body, W. W. Thoman	234,505
Hat ironing machine, Hedden & McCormick	234,569
Hatchway door mechanism, J. W. Evans	234,464
Hay press, B. M. Watts	234,509
Head light, locomotive, W. Kelley	234,410
Hides, machine for shaving wool or hair from, J. Curson	234,542
Hinge, gate, J. L. Anderson	234,382
Hopple, C. J. Gustaveson	234,562
Hydrocarbon burner, D. M. Graham	234,468
Hydrocarbon furnace, W. D. Dickey	234,395
Ice cutting machine, E. S. Field	234,397
Inhaler, gas, H. R. Hurd	234,479
Instep holder, McKay & Fairfield	234,488
Insulator, telegraph, C. Bigeon	234,523
Iron with oxide, coating, G. & A. S. Bower	234,524
Iron with zinc and alloys of zinc, coating, J. B. Jones	234,481
Ironing machine, J. Vandercar	234,631
Jewelers' use, tool for, L. G. Grady	234,560
Keg, lager beer, J. B. Hayden	234,473
Knitting machines, feed mechanism for circular, H. Clarke	234,535
Knob attachment, W. H. Gonne	234,466
Ladder, C. D. Cannon	234,389
Lantern holder, P. G. Stephenson	234,500
Lathe, gauge, F. W. Clough	234,536
Life preserver, C. D. Oatman	234,606
Lightning guard for oil tanks, A. A. Knudson	234,484
Limb, artificial, A. A. Marks	234,597
Lock, A. Lemke	234,592
Lock cylinder, H. R. Towne	234,630
Loom. A. L. & C. L. Bigsby	234,521
Lubricating apparatus, automatic, G. W. Baker	234,383
Machine brake, automatic, E. Pitman	234,426
Magnet, relay or sounder, G. Little	234,415
Malt, compressed, Prendergast & Free	234,428
Marble, etc., composition for cleaning, G. P. Cole	234,539
Meat cutter, R. Hübner.	234,470
Meat cutting machine, L. Steigert	234,499
Mercurial fumes, apparatus for condensing, T. W. Dresser	234,462
Metals from their ores, machine for separating precious, G. Hall	234,565
Mirror hanger, C. W. Prescott	234,609
Moulding machines, apparatus for turning cutters for, L. Wenchel	234,635
Mower, lawn, H. G. Fiske	234,553
Musical string instruments, key for, J. Singer	234,643
Needle wrapper, J. M. Woodward	234,514
Optometer, A. Mayer	234,598
Overalls, A. Clement	234,391
Overalls, L. H. Wise	234,512
Packing case, folding, W. H. Yaxley	234,450
Paint cans, machine for filling, W. M. Shoemaker	234,434
Pantaloons elevator, C. B. Plympton	234,427
Paper bag machine, O. E. Davidson	234,544
Paper cutting machine, J. M. Jones	234,409
Paper feeding machine, Griffith & Byrne	234,469
Paper, machine for fringing, S. Garrett	234,399
Paper machine pulp screen, S. L. Gould	234,559
Paper pulp digesters, etc., slide valve gate for, J. Saunders	234,431
Paper pulp pail, E. Hubbard	234,405
Paner tool, H. Dewey	234,545
Planter, check row seed, G. W. Fink	234,555
Planter, corn, Wickey & Brown	234,447
Planter, cotton seed, J. H. Walker	234,508
Plow and seed planter, combined, Sapp & Mantz	234,616
Plow, sulky, W. H. Ryer	234,615
Plumbers' traps, machine for making, F. N. Du Bois	234,463
Pocket, S. Marcus	234,487
Pocketbook, H. J. Lehman	234,414
Portable engine boiler, D. M. Swain	234,627
Preparations melting under 32° Fahrenheit, apparatus therefor, and their application, S. H. Rouart	234,494
Preserving animal and vegetable substances, compound for, J. Hauff	234,567
Pressure regulator, fluid, N. C. Locke (r)	9,466
Printing machines, stretching and drying apparatus for calico, F. J. Crowley	234,541
Printing presses, traversing inking roller for, A. Shedlock	234,433
Propelling vessels, mechanism for, B. Palmer	234,607
Pulley attachment, F. A. Kittell	234,585
Pump, P. E. Jay	231,407
Pump, L. M. Canavel	234,583
Pump, air, W. Auteurietti	234,516
Pump bucket, chain, Laraway & Rockwell	234,588
Pump, diaphragm ship's, J. Edson	234,551
Pump, steam, E. E. Miller	234,601
Radiator, steam, H. Mooers	234,419
Railway chair, J. H. Collingwood	234,458
Railway fish plate, W. Butcher	234,529
Railway signal, pneumatic, J. A. Emery	234,552
Railway signaling apparatus, F. J. Wenker	234,636
Railway switch, T. Solt	234,436
Railway time signal, H. A. Wayne	234,634
Refrigerator, S. B. Clemmens	234,457
Riddle and sieve, E. Oliver	234,605
Roofing and paving material, C. M. Warren	234,412
Roofing composition, C. F. Pearson	234,425
Rudders, raising and lowering ships', R. F. Loper, Jr.	234,594
Saccharine substances, treatment and preparation of, M. Weinrich	234,510, 234,511
Sash fastening, Burgess & Sanford	234,387
Seed huller, cotton, S. Kitchens, Sr.	234,584
Sewing machine, Koch & Wiese	234,587
Sewing machine, E. T. Thomas	234,628
Sewing machine, boot and shoe, E. Woodward	234,513
Sewing machine, button hole, J. H. Applegate	234,451
Sewing machine quilting gauge, J. H. Lavance	234,485
Sewing machine treadle, R. Steel	234,498
Seeding machines, spring hoe attachment for, S. B. Hart	234,566
Shirt, C. A. Gilbert	234,558
Sink outlet cover, J. W. Grows	234,102
Skate, roller, M. C. Henley	234,404
Smoke and gas consuming furnace, W. C. P. Bissell	234,885
Snow scraping machine, G. B. Gruman	234,470
Soda water and other liquids, apparatus for cooling, A. D. Puffer (r)	9,465
Soldering irons, rotary benzine furnace for heating, G. H. Perkins	234,424
Sole edge burnishing machine, Tayman & Bennor	234,504
Spinning frames, mechanism for supporting the spindles of ring, J. Birkenhead	234,522
Spout, sap, I. H. Spelman	234,437
Steam pipes, etc., covering for, J. Merriam	234,417
Steam trap, J. H. Blessing	234,886
Stencil, D. W. Ream	234,492
Stereotype matrices, drying, W. J. Johnson	234,480
Stove, gasoline, W. C. North	234,491
Stove grate, G. Froh (r)	9,463
Stove pipe shelf, S. Ayres	234,452
Stoves, portable extension top for, J. H. Hutchinson	234,575
String instruments, key for tuning, J. Singer	234,642
Telegraph, duplex. A. Muirhead	234,490
Telephone, J. H. Irwin	234,579
Telephone, speaking, S. D. Field	234,554
Telephone system, G. D'Infreville	234,578
Thill coupling, P. Klipple	234,483
Thill coupling. L. B. Lathrop	234,591
Thrashing or hulling cylinder, J. I. McClung	234,599
Thread cutter, M. D. Barringer	234,384
Tinned metal plates by heat and pressure, automatic apparatus for uniting, G. H. Perkins	234,423
Tobacco curing apparatus, A. Gordon	234,467
Tobacco leaves, apparatus for coloring, J. M. Henningsen	234,474
Tobacco, marking plug, W. Painter	234,608
Toilet case, C. Carroll	234,388
Tongue hound for wagons, R. W. McClelland	234,600
Tongue support, wagon. G. F. Wingate	234,446
Tool shank, A. H. Suplee (r)	9,472
Toothpick, E. Osgood	234,422
Toy horse and wagon, F. W. Carpenter	234,534
Toy money bank, C. A. Bailey	234,518
Truck. E. J. Leyburn	234,486
Trucks, rub iron for car, D. E. Small	234,621
Valve, J. P. Hillard	234,573
Valve, balanced, Moore & Pertz	234,602
Vehicle bow trimming, H. Higgin	234,574
Vehicle sand band, J. Hitchcock	234,572
Vehicle seat, F. Oppenheim (r)	9,464
Vehicle spring, G. E. Harris	234,403
Vehicle wheel, J. Ladner	234,589
Vehicle wheel, C. H. Triphagen	234,506
Wagon brake, Whitman & Igon	234,637
Wagon brake shoe, C. A. Skene	234,435
Washing machine, J. G. Crawford	234,393
Washing machine, L. Sternberger	234,438
Watch, acoustic, G. A. Bowen	234,455
Watch case, W. Calame	234,530
Watches, roller abstractor for, B. Frese (r)	9,467
Water closet, S. S. Hellyer	234,570
Water elevator, J. R. Cluxton	234,538
Wells, drilling machine for Artesian and oil, F. Knowlan	234,586
Whiffletree hook, C. Wright	234,449
Wind wheel, J. Sander	234,617
Windmill, Coriell & Adams	234,392
Windmill, W. C. Jacob	234,580
Wood, ornamenting, Pruyn & Hyatt	234,610
Wood turning machine, F. Hanson	234,472
Wrench and screw driver, comb'd, J. K. Collins	234,540

Fish, manufactured, Ferguson, Walker & Co	8,091
Hats, gentlemen's and boys' and ladies' and misses' soft felt, Topping Maynard & Hobron	8,096
Tobacco, plug, G. Wittler	8,097
Jewelry, comprising lace pins, scarf pins, earrings, ear drops, brooches studs, sleeve buttons, and scarf rings. Howard & Scherrieble	8,095
Soap, J. Oakley & Co.	8,094
Tobacco, smoking and chewing, Wilson & McCallay	8,092, 8,093
Yarn, cotton and woolen darning, H. C. Conkle	8,090

New York, 14 Dey Street.	San Francisco, 2 and 4 California St.
Chicago, 152 and 154 Lake St.	Philadelphia, 11 North Sixth Street.
St. Louis, 209 North Third St.	Boston, 21 Doane St.
St. Louis, 811 to 819 North Second St.	Portland, Oregon, 43 Front St.
Cincinnati, 212 West Second St.	London, Eng., 9 St. Andrews St., Holborn Viaduct, E. C.
Louisville, 427 West Main St.	Liverpool, Eng., 42 The Temple, Dale St.
Indianapolis, Corner Maryland and Delaware Sts.	Sydney, N. S. W., 11 Pitt St.
New Orleans, 26 Union St.