osc 



526 



OST 



fith in Cuviur's arrangement. Named 

 from egfles, straight, and -x<noi, a wing, 

 being characterised by two straight wings, 

 covered with soft and flexible cases or 

 elytra. They compose the two families, 

 Cursoria, or runners,, and Saltalnria, or 

 jumpers. The Cockroaches are examples 

 of the first, and the grasshoppers and 

 crickets of the second. All the orthoptera 

 are terrestrial; some are carnivorous, 

 some omnivorous, but the greater number 

 feed on living plants. 



OR'TIVE, Lat. ortivus, rising, or eastern. 

 The ortive amplitude of a heavenly body is 

 an arc of the horizon, intercepted between 

 the point where a star rises and the east 

 point of the horizon, the point where the 

 horizon and equator intersect. 



OR'TOLAN. A bird, the JSmberiza hor- 

 tulana, Lin., about the size of a lark ; 

 builds in hedges, is very fat, and common 

 in France, &c. in autumn. It is highly 

 celebrated in the annals of gastronomy, 

 and under the name of Miliaria was sold 

 at enormous prices to the epicures of 

 Home. 



OKVIE'TAN. A medicine once celebrated 

 as an antidote to poisons. Named after 

 Orvietanus, a mountebank, who invented 

 it, or from Orvieto, a town in the Papal 

 territories. 



ORYCTOG'NOSY, from o%vros, a mineral, 

 and yai<r/9, knowledge. 1. The name 

 given by Werner to what is otherwise 

 more generally named mineralogy (q. v.) 



2. That branch of mineralogy which 



has for its object the classification of 

 minerals, and the determination of their 

 nomenclature. 3. Oryctology. 



ORYCTOG'RAPHY, ) from egoxTSS, a fossil, 



ORYCTOL'OGY, ' and Aeyes, discourse. 

 1. That part of geology which treats of 

 fossils. 2. The same as oryctognosy. 



ORY'ZA. Rice. A genus of annual plant. 

 Hexandria Digynia. Name corrupted 

 from the Arabic orez. One species, the 

 O. sativa, which affords the rice, the chief 

 food of the inhabitants of all parts of the 

 east. It grows naturally in moist places, 

 and only comes to perfection in localities 

 where the ground is occasionally over- 

 flowed with water. 



OSCHEOC'ELE, from otr-^tov, the scrotum, 

 and xr^v), a tumour. 1. Any tumour of 

 the scrotum. 2. A scrotal hernia. 



OSCILLATION, Lat. oscillum, from cillo, 

 to move ; vibration. The reciprocal ascent 

 and descent of a pendulum. The axis of 

 oscillation is a right line, passing through 

 the point of suspension parallel to the 

 horizon. The centre of oscillation is that 

 point in an oscillating body into which, 

 *.'all the matter were collected, the vibra- 

 tions would be performed in the same 



tine. 



OSCILLATOR'! A. Minute organised be- 

 ings, having the power of making oscilla- 

 tory movements. 



Os COC'CTOIS. The tail-bone : the first 

 bone of the tail of tailed animals. 



OSCCLA'TION, from osculo, to kiss. A 

 term in geometry for the contact between 

 any given curve and its osculatary circle ; 

 i. e. a circle having the same curvature as 

 the given curve. 



OS'CDLATORY(*<- Oscr LATios). 1. Anos- 

 culatory is a tablet or board with the pic- 

 ture of Christ, the Virgin. &c., kept in 

 Romish churches, to be kissed by the 

 priest, and then delivered to the people 



for the same purpose. 2. For osculatory 



circle (see OSCULATION). 



OsiAN'DaiANS. In ecclesiastical history, 

 a sect of the Lutherans, founded by Osi- 

 ander. 



OS'MAZOME, from Offfvn, odour, and ?x,iK5, 

 juice. A peculiar animal principle, ob- 

 tained by digesting cold water for some 

 hours on slices of raw muscular fibre, eva- 

 porating the liquor to dryness, and treat- 

 ing the fixed remainder with alcohol, and 

 finally dissipating the alcohol by a gentle 

 heat. It has a brownish yellow colour, 

 and the taste and smell of soup. 



OS'MIUM, from off/Mij, smell. A metal 

 discovered by Tennant in crude platinum, 

 and thus named by him from the pungent 

 and peculiar smell of its oxide. It occurs 

 also associated with the ore of iridium. 

 Osmium has a dark grey colour, readily 

 combines with oxygen when heated in 

 the air, and is insoluble in acids, but 

 readily soluble in potassia. 



OS'NABORG. A sort of coarse linen, first 

 imported from Osnaburg in Germany. 



OSS'PRAY, | The sea-eagle or fish-hawk 



OSS'PREY. / (Falco ossifraga, Lin.) about 

 the size of a peacock. It feeds on fish, 

 which it takes by suddenly darting upon 

 them when near the surface of the water. 

 The name is a corruption of the Latin 

 ossifraga, the bone-breaker (os nn&frango). 



OS'SEANS OROs'sEi. In ichthyology , a pri- 

 mary division of fishes, including such as 

 have a bony skeleton. 



OSSIFICA'TIOX, from os, a bone, and 

 facio, to make. 1. The formation of bone : 

 osteogony. 2. In pathology, the conver- 

 sion of membraneous or muscular sub- 

 stances into a bony substance. 



OS'SEOUS, Lat. osseus, bony. Osseous 

 breccia is a mass of fragments of the 

 bones of animals, cemented together by a 

 calcareous gangue, and commonly found 

 in fissures and caves. 



OSTEN'SIVE, from ostendo, to show ; 

 showing. An ostensive demonstration is one 

 which plainly and directly demonstrates 

 the truth of a proposition, in contradis- 

 tinction to an apogogical one, or one 

 which depends upon a reductio ad altut- 



