Page:Cyclopaedia, Chambers - Supplement, Volume 2.djvu/164

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and ufcd in medicine, were the fruit of the fapapinus, or fa- pima ; and it is evident, that thefe muft be the produce of a pine tree, not of a pitch tree, or any thing of the fir kind. OR r HOCERATITES, in natural hiftory, a name by which fome late authors have called a fpecies of fea fhell, found fre- quently foffile, but not known at prefent in its recent (late ; called by others polytbalamium and tubuim marims concamera- t«s. It" is ufually frrait, but fometimes its end is twilled like the corral amiiKnis. See Tuisulis Concamcrati. ORTHODOXI, in botany, fuch fyftematic writers as have formed their methods on the true natural foundation, and di- vided the plants under their confideration into clanes and ge- nera, according to the characters of their parts of frufiifica- tion. Thefe are either the univerfales, or particulars ; by the firft are meant, thofe who have thus ranged the whole vegetable world ; and by the latter, thofe who have under- taken only fome one clafs of plants, as the umbelliferous, tjfe. Liumsi, Fund. Bot p. 2. ORTHODROMICS, that part of navigation which teaches the art of failing in the arch of fome great circle. The word is Greek, OpMfv««, derived from » f 0®-, rellus, flreight, and i>p®-, curfus, run or diftance ; q. d. the flreight or fhorteft diilance ; and this can only be in the arch of a great circle. OKTHRAGORISCUS, in zoology, the name ufed by Ronde- letius, and fome other authqrs.'for the fifh more commonly known by the name of the mola, and called in Englifh the fmfijb. IVilliiglibfs Hi&.?\k. p. 151. Seethe article Mola. ORTYGOMETRA, in zoology, the name of a bird called in Engliih the daker-hen. It is fomewhat larger than the quail. Its body, in (hape, refembles the common hen. It has two dusky lines on the head: its bread and belly are white: its throat of a dusky brown : its back feathers are black in the middle, and of a tawny colour at their edges : its thighs are variegated with transverfe-white ftreaks. It is common in Ireland, and in fome of the northern counties of England, particularly in Northumberland. The noife it makes is only crex, crex, whence the antients have called it by that name. The Italians call it re cdelle quaglie, or the king of the quails. It.is a very delicately tailed bird. Ray's Ornithol. p. 122. OR V ALA, in botany, the name given by Linnaeus to a genus of plants, ailed papia by Micheli. The characters are thefe : The pcrianthium is compofed of one leaf, it is tubulated and dilated at the mouth, and is crooked and divided into five fe» ments ; the lower two being fhorter than the reft. 1 The flower is compofed of one petal, and is not of the labiated kind ; the tube is of the length of the cup. The limb is erefl, long, and divided into four fegments. The upper of which is oblong, convex, and falcated and lunated at the point. The lower is oblong, and is alfo lunated at the point and the fide ones are oblong and pointed, and divided each ' into three fegment6. The flamina are four filaments of the length of the flower; they are placed under the upper feg- ments of the flower ; the antherse are two in number. The germen of the piftil is divided into four ; the ftyle is fimple, and of the fame length with the Itamina ; the ftigma is bifid, and acute. The feeds are four, and of an oval kidney-like Ihape. Linnai, Gen. Plant, p. 278. Orvala, in botany, is alfo a name ufed by fome authors for

the hprminum, or clary. Ger. Emac. Ind. 2. ORYCTOGRAPHY, is that part of natural hiftory wherein

foflils are defcribed. Wolfm. Difc. Praelim. Logic. §. 81. ORYCTOLOGY, is that part of phyfics which treats of fof- fils, or it is the fcience of foflils. Under this head comes the' doctrine of falts, fulphurs, (tones, gems and metals. Wolfm. Difc. Praelim. Logic. §.81. ORYGMA, ifvyfut, among the Athenians, a name given to the pit, more ufually called barathron; (See Barathron) whence the public executioner received the appellation of o is-1 tw (SfjfWli. It was a dark noifomc hole, and had fharp fpikes at the top, that no man might efcape out ; and others at the bottom, to pierce and torment fuch as were caft in. From its depth and capacioufnefs, it came to be ufed pro- verbially for a covetous mifer, or voracious glutton, that is always craving, and can never be fatisfied ; and fuch a one the Latins called barathro. Potter, Archseol. Grace. 1. 1 . c. 25. T. r. p. 134, feq. ORYX, in zoology, an animal mentioned by Ariftotle and Pliny, with only one horn. Pliny makes it a fpecies of wild goat ; but Columella thinks it was a kind of deer. It is faid, that this creature was of great ufe in Africa, to relieve the torched inhabitants from thirft, there being always found in its body veficles full of a very wholefome and pleafant li- quor. Hofm. Lex. in voc. ORYZEUM, a name given by many of the chemical writers

to gold. OS (C\cl.) — Os argenteum, in natural hiftory, the name of a fpecies of fhcll fifh, of the round mouthed fnail, or lumris achlea kind. It has a very elegant filver colour in the round open- ing, or mouth of the fhell: See Lunaris Cochlea. Os aureum, the golden mouth, in natural hiftory, a name given to a fpecies of cochleae of the lunar kind, or of that cenus which have a round mouth. This, in the OS aureum, is of a fine yellow. See Lunaris Cochlea,

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Os calcis (Cycl.) — This is the targeft bone of the foot, of which it makes the pofterior part, and in fome meafure the bafis. It is oblong and very irregular, and may be divided into a body and two apophyfes, one great and anterior, the other ("mailer, lateral and internal. The body of the os catch has fix fides ; one pofterior, one anterior, one fuperior, one inferior, and two later-al. The pofterior fide is broad, un- equally convex, and as it were divided into two portions, one fuperior, fmall and polilhcd, the other inferior, much larger, unequal, and rough, which, in children, is an apo- phyfis, and may be termed the tubemfvty of the r,s calcis. The lower part of it is bent downward, and terminates in two tubercles or obtufe points, which belong rather to the in- ferior than the pofterior hdes of the bone. The upper fide may be divided into two parts, one pofterior and unequal, having a fmall depretfion ; the other anterior, convex, and cartilaginous, proportioned to the great inferior cavity of the aftragalus. This fide is turned obliquely forward, and by this obliquity becomes part of the forefide, the remaining part of which is loft in the anterior apophyfis. The lower fide is narrow, and behind it lies the two tubercles already mentioned, of which the internal is the biggeft; they both ferve for the infertion of the aponeurofis in" the fole of the foot, but chiefly the higgeft. The two lateral fides are con- tinued over the anterior apophyfis, the external is gentlv con- vex and unequal, covered only with the common integuments and ligaments j the internal is hollow and deprefTed. The greater anterior apophyfis lies in the fame direction with the body, being a continuation thereof. It has five fides or re- markable parts, and were it not for the body -would have a fixth. The upper fide has an irregular and unequal depref- fion, which, together with that in the apophyfis of the aftra- galus, forms a considerable fofiiila. And its anterior extremi- ty has a fmall cartilaginous furface, anfwering to one of thofe in the apophyfis of the aftr'galus. The anterior fide of the apophyfis is broad, oblique, cartilaginous, partly convex and partly concave, and is articulated with a like furface of the os cuboides : this is the forefide of the whole os calcis, when confidered without any divifion. The outfide of the apophy- fis is very rough, being a continuation of the outfide of the body, with a tubercle or eminence of the place where the two fides meet. This, however, is not found in all fubjects. On the lower part of this tubercle is a cartilaginous furface for the paflage of the tendon of the peron&us hngiis: fome- times we fee only fome fmall vefiiges of this eminence, and often none. We fometimes alfo meet with a cartilaginous furface, fmall, lower down, and more forward, near the an- terior extremity of the apophyfis, for the paflage of the fame tendon. The lower fide is a tuberofity continued from the fide of the body, and defigncd for the infertion of mufcles. The lateral apophyfis is almoft common to the body, and to the great anterior apophyfis, and increafes the cavity on the infide of the os calcis. On its upper part it has a very fmooth cartilaginous furface, articulated with one of the inferior furfaces of the aftragalus. This apophyfis is very low down, and its inferior part is fmooth for the paflage of tendons. Wmsl.vfs Anatomy, p. 97, feq. Os calcis luxated. It fometimes happens, that the os cakis above, . and no other bone of the foot, is difplaced or luxated by fome external force j and this happens fometimes toward the ex- ternal, fometimes toward the internal fide of thefoot. When this accident happens, it is eafily difcovered by the violent pain it occafions j and by the inequality of the part, that is, there is a cayity plainly obfervable in one part, and a tumor in the other, on the place. The reduction of this dislocation is very eafy. The patient is to be placed on a bed, and. while two affiftants extend the limb in the oppofite directions, the furgeon replaces the di'flocated bone with his fingers, and the preflure of the palm of his hand, and then there is no more .than a proper bandage and reft required to the cure, Hciftcr, Surg. p. 174. Os cuneifmne. This in the carpus is the third bone of the firft row. It has its name from the Latin emeus, a wedge. Its figure much reprefenting that of a wedge flicking between the two rows. It has a rough furface with a fmall tubercle upon it, which forms the gceateft part of the cubital ede;e of the carpus ; and four articular fides of which one is convex, which compleats the articular convexity of the carpus, one orbicular and internal, or on the concave fide of the carpus, on which the os pififorme is fet ; and two others, which make an angle between them, one for the os femilunarc, and the other for the os unciforme. fflitr/Iaiv's Anatomy, p. S3. The offa citneiformia of the tarfus are fituated before the os fcaphoides The firft of them is the largeft, and the third the leaft j with the os cuboides, thefe form a fort , of arch, which on the fide next the other foot is high, and low on the oppofifce fide. In each' of thefe bones we may diftinguifb the bafis, the apex, and four fides, one pofterior, one anterior, and two lateral; whereof one Is in- ternal, the other external. The firft bone is like a wedge con- torted and bent. Its bafis is low down, unequally rcunded., Uke an oblong tuberofity, ferving for the inferriari of a ten- don; the internal lateral fide, or that which is turned tcwards- Ithe other foot, is unequally convex, and rough, for the infer- tion