The external form of the foot differs widely from that of the hand; and yet, when closely compared, the two present some singular resemblances. Thus the ankle corresponds in a manner with the wrist; the sole with the palm; the toes with the fingers; the great toe with the thumb. But the toes, or digits of the foot, are far shorter in proportion than the digits of the hand, and are less moveable, the want of mobility being most striking in the great toe--which, again, is very much larger in proportion to the other toes than the thumb to the fingers. In considering this point, however, it must not be forgotten that the civilized great toe, confined and cramped from childhood upwards, is seen to a great disadvantage, and that in uncivilized and barefooted people it retains a great amount of mobility, and even some sort of opposability. The Chinese boatmen are said to be able to pull an oar, the artisans of Bengal to weave, and the Carajas to steal fishhooks, by its help; though, after all, it must be recollected that the structure of its joints and the arrangement of its bones, necessarily render its prehensile action far less perfect than that of the thumb. But to gain a precise conception of the resemblances and differences of the hand and foot, and of the distinctive characters of each, we must look below the skin, and compare the bony framework and its motor apparatus in each (Fig. 18). The skeleton of the hand exhibits, in the region which we term the wrist, and which is technically called the _carpus_--two rows of closely fitted polygonal bones, four in each row, which are tolerably equal in size. The bones of the first row with the bones of the forearm form the wrist joint, and are arranged side by side, no one greatly exceeding or over-lapping the rest. The four bones of the second row of the carpus bear the four long bones which support the palm of the hand. The fifth bone of the same character is articulated in a much more free and moveable manner than the others, with its carpal bone, and forms the base of the thumb. These are called _metacarpal_ bones, and they carry the _phalanges_, or bones of the digits, of which there are two in the thumb, and three in each of the fingers. [Illustration: FIG. 18.--The skeleton of the Hand and Foot of Man reduced from Dr. Carter's drawings in Gray's "Anatomy." The hand is drawn to a larger scale than the foot. The line _a a_ in the hand indicates the boundary between the carpus and the metacarpus; _b b_ that between the latter and the proximal phalanges; _c c_ marks the ends of the distal phalanges. The line _a´ a´_ in the foot indicates the boundary between the tarsus and metatarsus; _b´ b´_ marks that between the metatarsus and the proximal phalanges; and _c´ c´_ bounds the ends of the distal phalanges; _ca_, the calcaneum; _as_, the astragalus; _sc_, the scaphoid bone in the tarsus.]