 | This articleneeds additional citations forverification. Please helpimprove this article byadding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Ogive" – news ·newspapers ·books ·scholar ·JSTOR(May 2013) (Learn how and when to remove this message) |
Anogive (/ˈoʊdʒaɪv/OH-jyve) is the roundlytapered end of a two- orthree-dimensional object. Ogive curves and surfaces are used inengineering,architecture,woodworking, andballistics.
The French OrientalistGeorges Séraphin Colin gives as the term's origin theArabical-ġubb (الجُبّ) 'cistern', pronouncedal-ġibb (الجِبّ) invernacular Iberian Arabic, through the Spanishaljibe or archaicallyalgibe.[1]
The earliest use of the wordogive is found in the 13th-century sketchbook ofVillard de Honnecourt, from Picardy in northern France. TheOxford English Dictionary considers the French term's origin obscure; it might come from theLate Latinobviata, the feminineperfect passive participle ofobviare, meaning the one who has met or encountered the other.[2] However, Merriam-Webster's dictionary says it is from the "Middle Englishoggif stone comprising an arch, from Middle Frenchaugive, ogive diagonal arch".[3] According to Wiktionary, the French term comes "from Vulgar Latin augīvus, from Latin augēre, as the ogive goes on increasing, and the arch it forms increases the strength of the vault. In Old French we find the phrase arc ogif, itself from Latin arcus augivus. The word was also written as augive in the 17th century."
| This sectiondoes notcite anysources. Please helpimprove this section byadding citations to reliable sources. Unsourced material may be challenged andremoved.(January 2020) (Learn how and when to remove this message) |
Inballistics oraerodynamics, an ogive is a pointed, curved surface mainly used to form the approximately streamlined nose of abullet or other projectile, reducing air resistance or thedrag of air. The French wordogive can be translated as "nose cone" or "warhead".
The traditional orsecant ogive is asurface of revolution of the same curve that forms aGothic arch; that is, acircular arc, of greaterradius than the diameter of thecylindrical section ("shank"), is drawn from the edge of the shank until it intercepts the axis.
If this arc is drawn so that it meets the shank at zero angle (that is, the distance of the centre of the arc from the axis, plus the radius of the shank, equals the radius of the arc), then it is called atangent orspitzer ogive. This is a very common ogive for high velocity (supersonic)rifle bullets.
The sharpness of this ogive is expressed by the ratio of its radius to the diameter of the cylinder; a value of one half being ahemispherical dome, and larger values being progressively more pointed. Values of 4 to 10 are commonly used in rifle bullets, with 6 being the most common.[citation needed]
Another common ogive for bullets is theelliptical ogive. This is a curve very similar to the spitzer ogive, except that the circular arc is replaced by an ellipse defined in such a way that it meets the axis at exactly 90°. This gives a somewhat rounded nose regardless of the sharpness ratio. An elliptical ogive is normally described in terms of the ratio of the length of the ogive to the diameter of the shank. A ratio of one half would be, once again, a hemisphere. Values close to 1 are common in practice. Elliptical ogives are mainly used inpistol bullets.
More complex ogives can be derived from minimumturbulence calculations rather than geometric forms, such as thevon Kármán ogive used for supersonic missiles, aircraft and ordnance.
One of the defining characteristics ofGothic architecture is thepointed arch.
Pointed arches may[original research?] have originated as in theSitamarhi caves in the 3rd century BCE. The free-standing temple of Trivikrama at Ter in Maharashtra (India) (dated to the Satavahana period of the 2nd century BCE to the 3rd century CE) also contains an ogive arch but it is constructed usingcorbel principles.
Excavations conducted byArchaeological Survey of India (ASI) at Kausambi revealed a palace with foundations from the 8th century BCE until the 2nd century CE, built in six phases. The last phase, dated to 1st–2nd century CE, includes an extensive structure which features four centered pointed arches which were used to span narrow passageways and segmental arches for wider areas.[4] Pointed arches with load-bearing functions were also employed inGandhara. A two pointed-arch vault-system was built inside theBhitargaon temple (as noted byAlexander Cunningham) which is dated to the earlyGupta period of the 4th–5th centuries CE.[5] Pointed arches also appeared in Mahabodhi temple with relieving arches and vaults between the 6th and 7th centuries CE.[6]
The 5th- or 6th-century CE Romano-ByzantineKaramagara Bridge in Cappadocia (in present-day Turkish Central Anatolia) features an early pointed arch as part of an apparent Romano-Greco-Syrian architectural tradition.[7]
Several scholars see the pointed arch as first established as an architectonic principle in theMiddle East inIslamic architecture during theAbbasid Caliphate in the middle of the 8th century CE.[8][6] Pointed arches appeared in Christian Europe by the 11th century CE.[9]
Some scholars have refused to accept an Indian origin of the pointed arch, including Hill[who?] (1993);[10][failed verification] some scholars have argued that pointed arches were used in theNear East in pre-Islamic architecture,[11] but others have stated that these arches were, in fact, parabolic and not pointed arches.[12]
Gothic architecture features ogives as the intersecting transverse ribs ofarches which establish the surface of a Gothicvault. An ogive or ogival arch is a pointed, "Gothic" arch, drawn with compasses as outlined above,[where?] or with arcs of an ellipse as described. A very narrow, steeply pointed ogive arch is sometimes called a "lancet arch". The most common form is anequilateral arch, where the radius is the same as the width. In the laterFlamboyant Gothic style, an "ogee arch", an arch with a pointed head, like S-shaped curves, became prevalent.
Inglaciology, the termogives refers to alternating bands of light and dark coloured ice that occur as a result of glaciers moving through anicefall.[13]
Definitions from Wiktionary
Media from CommonsThe enigmatic example which puzzled [Creswell] was Qasr Ibn Wardan, a building firmly dated to the reign of Justinian I, and he rightly concluded that the northern great arch still standing in the church there is slightly pointed [...]. This he attributed to a local, i.e. Syrian, influence and therefore concluded firmly that Syria was the home of the invention which was later to suffuse so much of the architecture of western Europe. Had he looked more widely in the Byzantine Empire he could have adduced other evidence of the priority of the Greeks.: for instance the Karamagara Bridge which spanned the River Murat near Elazig in Asia Minor, the slight but certain example of the apse arch of St. Apollinaire in Classe in Ravenna, and the insecurely dated but powerful apse arch of St. Irene in Constantinople, as well as examples in Syria itself.
[...] the first prominent monumental use of the pointed arch in Europe occurred at the third church of the Benedictine monastery at Cluny (Cluny III), built between 1088 and 1120 [...].
