I therefore willingly accede to your request for a Lecture upon some part of the anatomy of the human body, relying upon the intrinsic interest of the subject to make amends for my own deficiencies in expounding it; and I select the HUMAN FOOT, because a few of the more important points of its construction can be explained without much difficulty, because it affords a good illustration of some of the principles of animal mechanism, and because its form constitutes one of the great characteristics whereby man is distinguished from the lower animals. As an instrument of support and of locomotion it excels the foot of any other animal. It evinces its excellence by enabling man to stand upright in a way that no other animal can do; and so efficiently does the foot accomplish this and perform the task of carrying the body, that the hand is set at liberty to minister to the will. Thus is the foot instrumental in giving us an advantage over other animals, and in enabling us to provide the means of defence; and, thus, it aids us to carry out those wondrous works which are second only to the marvellous results of creative power. We are accustomed to regard the hand as the great agent by which all this is attained, and we are apt to forget how much it is indebted to the foot. We do not reflect that, if the foot of man presented no distinguishing peculiarity, the hand, like the corresponding part in other animals, would be compelled to share with it the task of carrying the body, and could, therefore, not be devoted to the various offices which it is now free to perform. Little right has the hand to say to the foot, “I have no need of thee.” _The principle of “division of labour.”_ In this concentration of locomotive power in the foot we have an illustration of what is called the “principle of division of labour,” a principle with which all civilized communities are familiar, and to which we are much indebted for the present advanced state of the arts and sciences; but which we may be said to have borrowed from the economy of nature. We find ever-increasing manifestations of it as we ascend in the animal series, from the lower and more simple to the higher and more complicated forms. Indeed, just as each step in civilization is attended with a further development of this principle, so is each division of the animal kingdom distinguished from those below it by the more distinct assignation of particular functions to particular organs, and by the consequent improvement of the mode in which the functions are performed. While, in proportion as the several organs acquire more distinct speciality in their work, so do they become, more and more, dependent upon one another, and, more and more, subjected to the control of central government, which is represented by the brain.