y 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
by another, forms, with the bones of the leg, the ankle joint; while a
third face, directed forwards, is separated from the three inner tarsal
bones of the row next the metatarsus by a bone called the 'scaphoid'
('sc').

Thus there is a fundamental difference in the structure of the foot and
the hand, observable when the carpus and the tarsus are contrasted; and
there are differences of degree noticeable when the proportions and
the mobility of the metacarpals and metatarsals, with their respective
digits, are compared together.

The same two classes of differences become obvious when the muscles of
the hand are compared with those of the foot.

Three principal sets of muscles, called "flexors," bend the fingers and
thumb, as in clenching the fist, and three sets--the extensors--extend
them, as in straightening the fingers. These muscles are all "long
muscles"; that is to say, the fleshy part o