The human foot and the human hand

by George Murray Humphry

THE Human Body is one of the most worthy objects of man’s study. It is the noblest as well as the crowning work of creation. In it material organization is carried to the greatest perfection. It surpasses, therefore, all other physical objects in exquisiteness of construction and in interest. How comes it, then, that most persons are so ignorant respecting it? Men, well informed in other matters, are usually altogether uninformed with regard to this. In every other branch of science we find amateur students pursuing the subject with zeal and success. Geology, Chemistry, Botany, Zoology, and even Comparative Anatomy have each their votaries; but Human Anatomy attracts no one. Why is this? Partly, I think, because opportunities for acquiring such information as is suitable and interesting are not so many as they ought to be.

It must be confessed, also, that we teachers of Anatomy are somewhat to blame. We are too prone, in our Lectures and Examinations, to dwell upon bare details, without enlivening those details with the many bright features of interest with which they are naturally invested; and we fail, therefore, to render it so attractive a science as it might be. The example of those able and animated teachers, John and Charles Bell, who laboured with some success to disperse the clouds that have ever overhung the horizon of anatomy, has been too much forgotten; and the flame which they kindled has almost died out under the chilling apathy of their successors. Truly glad should I be to see a change in this. I cannot but think that if the teachers of Anatomy took higher and more philosophical views of their science there would be no lack of interest on the part of the students. The interest so excited would soon spread beyond the limits of the profession; and there would thus be opened up to the public some of the products of that rich vein of knowledge and of that abundant material for thought which lie buried in the human frame.

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.

For instance, some of the lower animals, as the fresh-water Polyp, present nearly a uniform structure throughout their whole substance; and every part of them consequently performs the same function. There is not one organ for digestion, another for circulation, a third for respiration, and so on; but all these functions are performed by the same structure, and are performed, therefore, in a rude and imperfect manner. Any portion of the creature possesses all the requisites for its own nutrition, and is, so, independent of the remainder, and can live alone. Hence, the polyp may be divided into a number of pieces, each of which goes on living. Gradually, as we ascend from these lowly beings to the higher classes of animals, we find organs and functions more and more distinct from another; a Stomach is provided for the work of digestion, a Heart for circulation, Lungs for respiration. Each of these organs is essential to the existence of the others and of every part of the body; and they are all maintained in harmonious co-operation by the presiding influence of the nervous system.

Or, trace one of the functions in illustration of the same principle. Take the function of Locomotion, which has an especial relation to our present subject. In the Leech and the Worm the whole length of the body is occupied in the work, one part as much as another; and still, it is but a crawl. In the Fish the whole body is buoyed up by the water; it is flattened from side to side, and is all, from the head to the tail, concerned in the lateral stroke by which the animal is driven along; the side fins, which are the representatives of limbs, doing little beyond serving to guide and balance. In the other Vertebrates the work of locomotion is so far concentrated as to be assigned, almost entirely, to the limbs. All four limbs are in most of them devoted to it; while the bones and muscles of the trunk are only indirectly concerned in it. In Man, however, two limbs only are assigned to this important office. In him, therefore, the concentration of locomotive power, in other words the principle of division of labour, is carried out to the greatest extent—a disposition which affords one of the many proofs that the construction of his body combines with the faculties of his mind to place him at the head of the animal kingdom.

In making comparisons of different animals with one another, and in speaking of the relative perfection of their several organs, we must not forget that every organ of every animal is perfect as regards the purpose for which it was made. But some animals are said to occupy a higher position than others, or to be superior to others, because their mechanism is more complex, and they are, thereby, enabled to perform a greater variety of functions. And, in the animal kingdom, in proportion as each function rises into prominence, and becomes well and distinctly performed, so is a special organ assigned to it, and that organ becomes more and more highly elaborated.

You will not misunderstand me, then, when I say that concentration of function and perfection of structure usually go together. And, forasmuch as in the lower limbs of man there is a greater concentration of locomotive function than in any other part of any other animal, you will expect to find, in them, a greater perfection of locomotive mechanism—that is to say, a more complete combination of strength with variety, rapidity, and extent of movement—than is elsewhere to be met with.