Count Rumford | |
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 Portrait byMoritz Kellerhoven, 1792 | |
| Born | Benjamin Thompson (1753-03-26)26 March 1753 Woburn, Province of Massachusetts Bay, British America |
| Died | 21 August 1814(1814-08-21) (aged 61) Auteuil, Paris, France |
| Known for | Thermodynamics |
| Awards |
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| Scientific career | |
| Fields | Physics |
| Signature | |
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ColonelSir Benjamin Thompson, Count Rumford,FRS (26 March 1753 – 21 August 1814), was an American-born British military officer, scientist and inventor. Born inWoburn, Massachusetts, he supported theLoyalist cause during theAmerican War of Independence, commanding theKing's American Dragoons during the conflict. After the war ended in 1783, Thompson moved to London, where he was recognised for his administrative talents and received a knighthood fromGeorge III in 1784.
A prolific scientist and inventor, Thompson also created several new warship designs. He subsequently moved to theElectorate of Bavaria and entered into the employ of the Bavarian government, heavily reorganising theBavarian Army. Thompson was rewarded for his efforts by being made anImperial Count in 1792 before dying in Paris in 1814.[1]
Thompson was born in ruralWoburn, in theProvince of Massachusetts Bay, on 26 March 1753; hisbirthplace is preserved as a museum. He was educated mainly at the village school, although he sometimes walked almost ten miles toCambridge with the olderLoammi Baldwin to attend lectures by ProfessorJohn Winthrop ofHarvard College. At the age of 13 he was apprenticed to John Appleton, amerchant of nearbySalem. Thompson excelled at his trade, and coming in contact with refined and well educated people for the first time, adopted many of their characteristics including an interest inscience. While recuperating in Woburn in 1769 from an injury, Thompson conducted his first experiments studying the nature ofheat and began to correspond with Baldwin and others about them. Later that year he worked several months for a Boston shopkeeper and then apprenticed himself briefly, and unsuccessfully, to a doctor in Woburn.
Thompson's prospects were dim in 1772 but in that year they changed abruptly. He met, charmed and married a rich and well-connected widow, an heiress named Sarah Rolfe (née Walker). Her father was a minister, and her late husband left her property at Rumford,Province of New Hampshire, which is today in the modern city ofConcord. They moved toPortsmouth, and through his wife's influence with the governor, he was appointed a major in theNew Hampshire Militia. Their child (also namedSarah) was born in 1774.[2]
Following the outbreak of theAmerican Revolutionary War in 1775, Thompson, by now a wealthy and influential landowner, came out as aLoyalist. He was soon using his connections in the colonial militia to recruit and arm Loyalists seeking to fight alongside the British against rebel forces, which earned him the enmity ofPatriots in New Hampshire. Thompson was stripped of his militia commission and a Patriot mob attacked and burned down his house, causing him to flee to British lines, abandoning his wife in the process. He became a political and military advisor to GeneralThomas Gage (to whom Thompson was already passing information on Patriots), and later assistedLord George Germain in organizing and provisioning Loyalist military units.[citation needed]
In 1781, Thompson raised his own military unit, theKing's American Dragoons, which was primarily stationed onLong Island in 1782 and early 1783, where they became notorious for demolishing a church and burial ground in order to erectFort Golgotha inHuntington, New York.[3]
"By 1775 Thompson had sailed for England, where under the auspices of theSecretary for the ColoniesLord George Germain he rose very rapidly in the service of the British government."[4]
During his military career, Thompson conducted experiments to measure the force ofgunpowder, the results of which were widely acclaimed when published in 1781 in thePhilosophical Transactions of theRoyal Society.[5]
In 1779, he was elected a Fellow of theRoyal Society[6] On the strength of hisRoyal Society publication, he arrived inLondon at the end of the war with a reputation as an accomplished scientist.
On 23 February 1784,George III conferred upon him the honor ofknighthood.[6][7][8][9]
In 1799, theRoyal Institution was founded as the result of a proposal by Thompson, for the "formation by Subscription, in the Metropolis of theBritish Empire, of a Public Institution for diffusing the Knowledge and facilitating the general Introduction of useful Mechanical Inventions and Improvements, and for the teaching by courses of Philosophical Lectures and Experiments, the application of Science to the Common Purposes of Life".[10]
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In 1785, he moved toBavaria where he became anaide-de-camp to thePrince-electorCharles Theodore. He spent eleven years in Bavaria, reorganizing the army and establishingworkhouses for the poor. He also inventedRumford's Soup, a soup for the poor,[11] and established the cultivation of thepotato in Bavaria. He studied methods of cooking, heating, and lighting, including the relative costs and efficiencies ofwaxcandles,tallowcandles, andoil lamps.[12]On Prince Charles' behalf he created theEnglischer Garten inMunich in 1789; it remains today and is known as one of the largest urban public parks in the world. He was elected a Foreign Honorary Member of theAmerican Academy of Arts and Sciences in 1789.[13]
For his efforts, in 1791 Thompson was made anImperial Count, becomingReichsgraf von Rumford. He took the name "Rumford" after the town of Rumford, New Hampshire, which was an older name forConcord where he had been married.[14]
Benjamin Thompson has many claims on the interest of the historian of science. He founded the Royal Institution. His methods of conservation of heat and economy of fuel, his designs of stoves, fireplaces and cooking utensils were widely used during his lifetime. He was consulted on the laying out of kitchens in hospitals and institutions. He taught his contemporaries to recognise the fire built on an open hearth, the only means of domestic heating and cooking with which they were acquainted, for the ineffective and wasteful contrivance it really was. He held the most enlightened views, far in advance of his time, on the waste of fuel and the evils of atmospheric pollution in cities.Rumford's constant preoccupation was the application of scientific principles to the improvement of the lot of the poor and the working classes, and it was in the subject of heat and its utilization that he found the greatest outlet for his endeavours.[15]
— Thomas Martin, The Experimental Researches of Benjamin Thompson, Count Rumford
His experiments on gunnery and explosives led to an interest in heat. He devised a method for measuring thespecific heat of a solid substance but was disappointed whenJohan Wilcke published his parallel discovery first.
Thompson next investigated theinsulating properties of various materials, includingfur,wool andfeathers. He correctly deduced that the insulating properties of these natural materials arise from the fact that they inhibit theconvection of air. He then inferred — incorrectly — that air and, in fact, all gases, were perfect non-conductors of heat.[16][17] He further saw this as evidence of theargument from design, contending thatdivine providence had arranged for fur on animals in such a way as to guarantee their comfort.
In 1797, he extended his claim about non-conductivity to liquids.[18] The idea raised considerable objections from the scientific establishment,John Dalton[19] andJohn Leslie[20] making particularly forthright attacks. Instrumentation far exceeding anything available in terms of accuracy and precision would have been needed to verify Thompson's claim. Again, he seems to have been influenced by his theological beliefs,[21] and historian of scienceD. S. L. Cardwell speculated that Thompson wished to grant water a privileged and providential status in the regulation of human life.[22]
He is considered the founder of thesous-vide food preparation method owing to his experiment with a mutton shoulder. He described this method in one of his essays.[23]
Rumford's most important scientific work took place in Munich, and centred on the nature of heat, which he contended in "An Inquiry Concerning the Source of the Heat Which Is Excited by Friction" (1798) was not thecaloric of then-current scientific thinking but a form ofmotion. Rumford had observed the frictional heat generated by boring cannon at the arsenal in Munich. Rumford immersed a cannon barrel in water and arranged for a specially blunted boring tool.[24] He showed that the water could be boiled within roughly two and a half hours and that the supply of frictional heat was seemingly inexhaustible. Rumford confirmed that no physical change had taken place in the material of the cannon by comparing the specific heats of the material machined away and that remaining.
Rumford argued that the seemingly indefinite generation of heat was incompatible with the caloric theory. He contended that the only thing communicated to the barrel was motion.
Rumford made no attempt to further quantify the heat generated or to measure the mechanical equivalent of heat. Though this work met with a hostile reception, it was subsequently important in establishing the laws ofconservation of energy later in the 19th century.
He explainedPictet's experiment, which demonstrates the reflection of cold, by supposing that all bodies emit invisible rays, undulations in the ethereal fluid.[25] He did experiments to support his theories of calorific and frigorific radiation and said the communication of heat was the net effect of calorific (hot) rays and frigorific (cold) rays and the rays emitted by the object. When an object absorbs radiation from a warmer object (calorific rays) its temperature rises, and when it absorbs radiation from a colder object (frigorific rays) its temperature falls. See note 8, "An enquiry concerning the nature of heat and the mode of its communication" Philosophical Transactions of the Royal Society, starting at page 112.[full citation needed]
Thompson was an active and prolific inventor, developing improvements for chimneys, fireplaces and industrial furnaces, as well as inventing adouble boiler, akitchen range, and acoffee drip-press pot[26][27][28] roughly between 1810 and 1814. He invented a percolating coffee pot following his pioneering work with the Bavarian Army, where he improved the diet of the soldiers (Rumford's Soup) as well as their clothes.[29]
TheRumford fireplace created a sensation in London when he introduced the idea of restricting the chimney opening to increase the updraught, which was a much more efficient way to heat a room than earlier fireplaces. He and his workers modified fireplaces by inserting bricks into the hearth to make the side walls angled, and added a choke to the chimney to increase the speed of air going up the flue. The effect was to produce a streamlined air flow, so all the smoke would go up into the chimney rather than lingering and entering the room. It also had the effect of increasing the efficiency of the fire, and gave extra control of the rate of combustion of the fuel, whether wood orcoal. Many fashionable London houses were modified to his instructions, and became smoke-free.[29]Thomas Jefferson used theRumford fireplace design atMonticello.[30][31]
Thompson became a celebrity when news of his success spread. His work was also very profitable, and much imitated when he published his analysis of the way chimneys worked. In many ways, he was similar toBenjamin Franklin, who also invented a new kind of heating stove.
The retention of heat was a recurring theme in his work, as he is also credited with the invention ofthermal underwear.[32]
Thompson also significantly improved the design of kilns used to producequicklime, andRumford furnaces were soon being constructed throughout Europe. The key innovation involved separating the burning fuel from the limestone, so that the lime produced by the heat of the furnace was not contaminated by ash from the fire.
Rumford worked inphotometry, the measurement of light. He made a photometer and introduced thestandard candle, the predecessor of thecandela, as a unit ofluminous intensity. His standard candle was made from the oil of a sperm whale, to rigid specifications.[33] He also published studies of "illusory" or subjective complementary colours, induced by the shadows created by two lights, one white and one coloured; these observations were cited and generalized byMichel-Eugène Chevreul as his "law of simultaneous colour contrast" in 1839.[34]
After 1799, he divided his time between France and England. With SirJoseph Banks, he established theRoyal Institution ofGreat Britain in 1799. The pair chose SirHumphry Davy as the first lecturer. The institution flourished and became world-famous as a result of Davy's pioneering research. His assistant,Michael Faraday, established the Institution as a premier research laboratory, and also justly famous for its series of public lectures popularizing science. That tradition continues to the present, and the Royal InstitutionChristmas lectures attract large audiences through their TV broadcasts.
Thompson endowed theRumford medals of theRoyal Society and theAmerican Academy of Arts and Sciences, and endowed theRumford Chair of Physics atHarvard University. In 1803, he was elected a foreign member of theRoyal Swedish Academy of Sciences, and as a member of theAmerican Philosophical Society.[35]
In 1772, Thompson married a rich and well-connected widow, an heiress named Sarah Rolfe (née Walker). Her father was a minister, and her late husband left her property at Rumford,Province of New Hampshire, which is today in the modern city ofConcord. They moved toPortsmouth, and through his wife's influence with the governor, he was appointed a major in theNew Hampshire Militia. Their child (also namedSarah) was born in 1774.[36] Thompson abandoned his American wife, Sarah, at the outbreak of the American Revolution; she died in 1792.[37]
After several affairs and a close friendship with Lady Emily (Amelia[38][39]) Mary Lamb Temple[40] (21 April 1787...11 September 1869), Viscountess Palmerston,[41](born Mary Mee[42]), in 1804, he marriedMarie-Anne Lavoisier, the widow of the great FrenchchemistAntoine Lavoisier. Thompson separated from his second wife after three years, but he settled inParis and continued his scientific work until his death on 21 August 1814. Thompson is buried in the small cemetery ofAuteuil in Paris, just across fromAdrien-Marie Legendre. Upon his death, his daughter from his first marriage,Sarah Thompson, inherited his title as Countess Rumford.
Some periodicals and satirical publications of Rumford’s time made references that associated him with men who were publicly linked to homosexuality, notablyGeorge Germain, 1st Viscount Sackville.[43][44][45]. Rumford’s surviving letters and papers do not contain evidence of same-sex relationships, and no independent contemporary documentation corroborates the claims.
Poland–Lithuania:Order of the White Eagle (1789).Mr. P. Carr informed me two days ago that you wished for the dimensions of the Rumford fireplaces. I therefore avail myself of the first post to send them. I state them as I have used them myself, with great satisfaction, the back one half of the opening. Count Rumford makes the back but one third of the opening...
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| Political offices | ||
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| Preceded by W. Knox T. De Grey | Under-Secretary of State for the Colonies with W. Knox 1780–1781 | Succeeded by W. Knox J. Fisher |
