The Committee on Science and the Arts of the Franklin Institute of
Pennsylvania thus stated the peculiarities of Mr. Palmer's invention:--

"_First,_ An ingenious arrangement of springs and cords in the _inside_
of the limb, by which, when the wearer is in the erect position, the
limb is extended, and the foot flexed so as to present a natural
appearance.

"_Second_. By a second arrangement of cords and springs in the inside of
the limb, the foot and toes are gradually and easily extended, when
the heel is placed in contact with the ground. In consequence of this
arrangement, the limping gait, and the unpleasant noise made by the
sudden stroke of the ball of the foot upon the ground in walking, which
are so obvious in the ordinary leg, are avoided.

"_Third_. By a peculiar arrangement of the knee-joint, it is rendered
little liable to wear, and all lateral or rotary motion is avoided. It
is hardly necessary to remark that any such motion is undesirable in an
artificial leg, as it renders its support unstable."

Before reporting some of the facts which we have seen, or learned by
personal inquiry, we must be allowed, for the sake of convenience,
to exercise the privilege granted to all philosophical students, of
enlarging the nomenclature applicable to the subject of which we are
treating.

Man, according to the Sphinx, is successively a _quadruped_, a _biped_,
and a _triped_. But circumstances may change his natural conditions. If
he loses a leg, he becomes a _uniped_. If he loses both his legs, he