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 I&7 Part I. A N A T O M Y. the foot; and on the knob, the thia flat cartilage proper The three cuneiform bones are all fb fecured by ligaments, that very little motion is allowed in any of them. to this mufcle plays; in place of which, fornetimes a bone is found:—More externally than the knob, a rough Thefe feven bones of the tarfus, when joined, are hollow is made, for the ftrong ligaments ftretched be- convex above, aftd leave a concavity below, for lodging twixt this bone and the os calcis.—Before, the furface fafely the feveral mufcles, tendons, veffels, and nerves of the os cuboides is flat, fmooth, and flightly divided that lie in the foie of the foot.—In the recent fubjedi, into two planes, for fuftaining the os metatarli of the their upper and lower furfaces are covered with ftrong ligaments, which adhere firmly to them ; and all the bones little toe, and of the toe next to it. The form of the back-part of the os cuboides, and are fo tightly connedfed, by thefe and the other ligathe ligaments connedting the joint there with the os cal- ments, which are fixed to the rough ridges and fofias cis, both concur in allowing little motion in this part. formerly mentioned, that, notwithftanding the many Os cuneiibrme externum, is much of the fliape of a furfaces covered with cartilage, fome of which are of wedge, being broad and flat above, with long fides run- the form of the very moveable articulations, no more ning obliquely downwards, and terminating in a fliarp motion is here allowed, than only to prevent too great a. edge.—The upper furface of this bone is an oblong fhock of the fabric of the body in walking, leaping, fee. fquare.—The one behind is nearly a triangle, but not by falling on too folid a bafe. complete at the inferior angle, and is joined to the os na- Metatarsus is compofed. of five bones, which, in viculare.—The external fide is an oblong fquare, divided their general charadters, agree with the metacarpal as it were by a diagonal: The upper half of it is fmooth, bones ; but may be diftinguifhed from them by the for its conjundlion with the os cuboides: The other is a following marks : i. They are longer, thicker, and fcabrous hollow ; and in its fuperior anterior angle, a ftronger. 2. Their anterior round ends are not fo fmall fmooth impreffion is made by the os metatarfi of broad, and are lefs in proportion to their bafes. 3. Their the toe next to the little one.—The internal fide of this bodies are fharper above and flatter on the fides, with bone is alfo quadrangular, with the foi e-part of its edge their inferior ridge inclined more to the outflde. 4. The made flat and fmooth by the os metatarfi of the toe next tubercles at the lower parts of the round head are larger. to the great one; and the back-part is alfo flat and fmooth, The firft or internal metatarfal bone is eafily diltinwhere the os cuneiforme medium is contiguous to it.— guifhed from the reft by its thicknefs.—The one next to The fore-part of this bone is an oblong triangle, for fu- it is, the longeft, and with its fharp edge almoft perpendicular. The others are fhorter and more oblique, as ftaining the os metatarfi of the middle toe. Os cuneiforme medium, or minimum, is flill more ex- their fituarion is more external. actly the fhape of a wedge than the former. Its up- Os metatarfi pollicis is by far the thickeft and ftrongper part is fquare.;—its internal fide has a flat fmooth eft, as having much'the greateft weight to fuftain. Its furface above and behind, for its conjundHon with the bafe is oblong, irregularly concave, and of a femilunar following bone; with a fmall rough fofla below ; and a figure, to be adapted to the os cuneiforme maximum.— confiderable fhare of it is rough and hollow.—The ex- The inferior edge of this bafe is a little prominent and ternal fide is fmooth and a little hollowed, where it is rough, where the tendon of the peronseus primus mufcontiguous to the laft defcribed bone.—Behind, this bone cle is inferted. On its outfide, an oblique circular deis triangular, where it is articulated with the os navicuiare; preflion is made by the fecond metatarfal bone. Its and it is alfo triangular at its fore-part, where it is conti- round head has generally on its fore-part a middle ridge, guous to the os metatarfi of the toe next to the great one. and two oblong cavities, for the offa fefamoidea; and Os cuneiforme maximum, or internum, differs from on the external fide, a deprefiion is made by the following the two former in its fituation, which is more oblique than theirs.—Befides, its broad thick part is placed be- bone. Os’metatarfi of the lecond toe, is die longeft of the low, and the fmall thin point is above and outwards; five, with a triangular bafe fupported by the os cuneiwhile its under broad furface is concave, for allowing a forme medium and the external fide produced into a prqfafe paflage to the flexors of the great toe.—-The fur- cefs; the end of which is an oblique fmooth plane, joinface of this os’ cuneiforme behind, where it is joined to ed to the os cuneiforme externum. Near the internal the os navicuiare, is hollow, fmooth, and of a circular of the hafe, this bone has two fmall depreflions, figure below, but pointed above.—The external fide edge by the os. cuneiforme maximum, between which is confifts of two fmooth and flat*furfaces, whofe diredtion amade rough cavity.—Farther forwards, we may obferve a is nearly at right angles with each other. With the po- fmooth protuberance, which is joined to the foregoing, fterior, that runs obliquely from below forwards and up- bone. On the outfide of the bafe are two oblong; wards, the os cuneiforme minimum is joined; and with fmooth lurfaces, for its articulation the following the anterior, whofe direction is longitudinal, the os me- bone ; the fuperior fmooth furface beingwithextended longitatarfi of the toe next to the great one is connedted.— tudinally, and the inferior perpendicularly ; between The fore-part of this bone is femilunar, but flat and which there is a rough folia. fmooth, for fuftaining the os metatarfi of the great toe. Os metatarfi of the middle toe, is the fecond in length. -—The internal fide is fcabrous, with two remarkable ■—Its bafe, fupported the os cuneiforme tubercles below, from which the mufculus abdudfor pol- is triangular, but flantingby outwards, where it externum, ends in a licis rifes, and the tibialis anticus is inferted into its up- lharp-pointed little prcctfs and the angle below is. not per part. completed. The