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 overlapping 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.

The skeleton of the foot is very like that of the hand in some respects.
Thus there are three phalanges in each of the lesser toes, and only two
in the great toe, which answers to the thumb. There is a long bone,
termed 'metatarsal', answering to the metacarpal, for each digit; and
the 'tarsus', which corresponds with the carpus, presents four short
polygonal bones in a row, which correspond very closely with the four
carpal bones of the second row of the hand. In other respects the foot
differs very widely from the hand. Thus the great toe is the longest
digit but one; and its metatarsal is far less moveably articulated with
the tarsus, than the metacarpal of the thumb with the carpus. But a
far more important distinction lies in the fact that, instead of four
more tarsal bones there are only three; and, that these three are not
arranged side by side, or in one row. One of them, the 'os calcis' or
heel bone ('ca'), lies externally, and sends back the large projecting
heel; another, the 'astragalus' ('as'), rests on this by one face, and