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XXX (188) XXX

i S3 A N A T O M Y. part!. The internal fide of this bafe is adapted to the pre- is proportionally much longer than the bones of the feceding bone ; and the external fide has alfo two fraooth cond and third, which are very (hort. furfaces covered with cartilage, but of a different figure; Of the four, the toe next to the great one has the for the upper one is concave, and, being round behind, largeft bones in all dimenfions, and more externally the turns fmaller as it advances forewards; and the lower toes are lefs.—The little toe, and frequently that next furface is little, fmooth, convex, and very near the edge to it, have the fecond and third bones intimately uniof the bafe. ted into one; which may be owing to their little motion, Os metatarfi of the fourth toe, is near as long as the and the great preffure they are fubjedled to. former, with a triangular flanting bafe, joined to the os c‘u- The toes are of good ufe to us in walking; for, when boides, and made round at its external angle, having one the foie is raifed, they bring our body, with its centre hollow fmooth furface on the outfide, where it is preffed of gravity, perpendicular to the advanced foot. upon by the following bone, and two on the internal The only bones now remaining to complete the defide, correfponding to the former bone ; behind which fcription of the Ikeleton, are the fmall ones, which are is a long narrow furface impreffed by the os cuneiforme found at the joints of the fingers and toes, and in fome other parts, called externum. Os metatarfi of the little toe, is the Ihorteft, fituated Ossa Sesamoidea, which are of very different fiwith its two flat fides above and below, and with the gures and fizes, though they are generally faid to referalidges laterally. The bale of it, part of which reds ble the feed of the fefamum.- -They feem to be noon the os cuboides, is very large, tuberous, and produ- thing elfe than the ligaments of the articulations, or the ced intp a long-pointed procefs externally, where.part firm tendons of firong mufcles, or both, become bony, of the abduftor minimi digiti is fixed; and into its up- by the compreflion v/hich they fuffer. Thus the fefaper part the peronaeus fecundus is inferted. Its infide moid bones at the beginning of the gaftrocnemii mufcles, has a flat conoidal furface, where it is contiguous to the are evidently compofed of the tendinous fibres only.— Thefe, at the firfi joint of the great toe, are’ as plainly preceding bone. When we Hand, the fore-ends of thefe metatarfal the fame continued fubftance with the ligaments and the bones, and the os calcis, are our only fupporters; and tendons of the addudtor, flexor, brevis, and abduftor.—£therefore it is neceffary they Ihould be ftrong, and ftiould That which is fometimes double at the fecond joint of that .toe, is part of the‘capfular ligament; and if we ehave a confined motion. The bones of the Toes are much akin to thofe of the numerate the other fefamoid bones that are at any time thumb and fingers; particularly the two of die great found, we may obferve all of them formed in this mantoe are precifely formed as the two laft of the thumb; ner. Their number, figure, fituation, and magnitude, only their pofition, in refpedt of the other toes, is not are fo uncertain, that it were in vain to infill on the difoblique; and they are proportionally much fixonger, be- ferences of each; and therefore we lhall only in general caufe they are fubje&ed to a greater force; for they fu- remark, ftain the force with which our bodies are pulhed forwards x. That where-ever the tendons and ligaments are by the foot behind at every ftep we make; and on them firmeft, the addons of the mufcles llrpngeft, and the principally the weight of the body is fupported, when we compreflion greateft, there fuch bones' are moll commonly found. are raifed on our tiptoes.. The three bones in each of the other four toes, com- 2. Thar, cneteris paribus, the older the fubjedt is in pared to' thofe of the fingers, differ from them in thefe which they are fought, their number is greater, and their particulars.- They are lefs, and fmaller in proportion fize is larger. to their lengths: — Their Safes are much larger than 3. The more labour any perfon is inured to, he has, their anterior ends: Their bodies are more narrow above cateris paribus, the moil numerous and largell offa fefaand below, and flatter on the fides.—The firft phalanx moidea. EXPLANATION of PLATE XIII. Figure L A Male Skeleton. A, Os frontis. B, Os parietale. C, Os temporum. D, Os occipitis. E, Offa nafi. F, Os malae. G, Os maxillare fuperius. H, Os maxillare inferius. I, The teeth, which are fixteen in each jaw. ]£* The feven vertebra of the neck, with their intermediate cartilages. L, <bc. The twelve dorfal vertebra, with their intermediate-cartilages. M, The five lumbar vertebra, and, N,Their intermediate cartilages*.-O, Gs

facrum. P, Os coccygis. 0> Os ilium. R, Os pubis. S, Os ifchium. T, The leven true ribs. U, Thfe five falfe ribs. V, The fternum. X, The clavicle. Y, The fcapula. Z, The os humeri, a, Ulna, b, Radius. c. The eight bones of the carpus, d. The five metacarpal bones, e. The phalanges of the fin-r gers. f, TEe os femoris. g, The patella, h, The tibia, i, The fibula, k, The feyen bones of the tarfus. 1, The five metatarfal bones, m, The phalanges of the toes.