A number of valuable books have been written on the fundamental principles of locomotion by means of walking, riding upon animate beings, flying and creeping, and also upon all kinds of inanimate or mechanical motors, but little has been said about physical properties underlying the intervention of a wheel between the body of man and the surface to be travelled over, the motor being man himself.
The interesting art of man-motor carriages has already developed an industry of such great importance that the certainty as to its permanency is beyond cavil, and, believing that it will yet assume much greater proportions and become of more and more absorbing interest, there seems to be some excuse for an attempt to place even a limited amount of personal information before those connected with the industry and before the admirers of the art. There are few industries the product of which is dispersed among so varied a class of patrons, and scarcely none in which the patron takes so lively an interest in the respective articles produced.
In most industries, where a machine is the product, the consumer is expected to be an expert in the art to which the industry appertains, and is therefore supposed to be capable of individual judgment as to the merits of what he acquires; if a steam-engine is the object of the purchase, it is expected that an expert of some ability in the art will judge of and afterwards run and repair it; but how could this be expected with a bicycle?
There is probably no other machine used by mankind, with the possible exception of the watch, that does service to such a variety of individuals as the cycle. Now, it would be of little use to write a book for popular reading on the mechanical construction of a watch, because from its very nature none but an expert could appreciate the facts, if any were given; but greater hope might be entertained in regard to a larger machine, because the buyer can at least see what he is about. You never heard of a bicycle-rider blaming his repairer for stealing the wheels out of his machine and substituting others, because he can see, however inexperienced he may be, that this has not been done. Now, if we all could, by a little observation, learn one-half as much about our watches as we can about our bicycles, the poor watch-maker would never suffer the indignities so universally and unjustly heaped upon him. The primary knowledge above hinted at as possible, among the hoped-for patrons of this work, seems to be an auspicious circumstance in connection with an effort to teach them a little more.
CHAPTER III.
CAN WE IMPROVE UPON THE CREATOR’S METHODS?
“We find in a great number of standard treatises a sort of accusation brought against nature for having entirely wasted a great part of the force of our muscles by causing them to act under a disadvantageous leverage.”—E. J. Marey.[1]
À propos of fundamental principles, what are the requirements needful for the most successful means of man-motor locomotion? In more homely phrase, how can a man, without calling upon the storage of energy other than that inherent in his own body, propel himself from place to place with the least amount of physical exertion? It is evident now, that under very many circumstances the means provided us by the Creator for such purposes are not the most economical; that is to say, it has been found that if we employ a medium through which to transmit our energy, the energy will be more economically expended, in carrying our bodies from place to place, than if we apply the force directly to the work as nature seemed to intend in presenting us with a pair of legs. The writer cheerfully concedes, for one, that for almost all purposes the legs are very practical; as, for instance, in climbing a tree or a pair of stairs, a rail fence, or even a very steep hill, or when, as in some of our early travels, we are compelled by an embarrassing paucity of funds to take to the cross-ties of a poorly ballasted railroad. And further, we admit that the invention of a pair of legs, if properly claimed in a patent, would, with perfect justice, have entitled the inventor to all uses to which they could be put, including the pumping of a bicycle. But we are perfectly willing to infringe the leg patent, provided we can improve upon it even for certain purposes, as we have in adopting the modern bicycle, in its use, for instance, upon a reasonably smooth level road. Why we have been able to thus improve upon nature’s device is not quite clear. Undoubtedly, however, there is some unnecessary friction in the leg method; it cannot be on account of impact with the air, because a man on a bicycle certainly catches as much air himself, in addition to that of the machine, as he would do in walking. Evidently, then, there must be more motion or extra friction or both in the body, in the leg method, than is really essential in conveying one over a good road. Probably the main cause of this friction is that the rider’s body is supported differently; it requires less muscular strain to sit than to stand. We not only know this from experience, but it is proved by the fact that the temperature of the body is lower while sitting than while standing; also still lower when lying down, showing that less energy is being expended and less muscle consumed. Since the spirit of the writer began to wrestle with the foregoing leg versus cycle controversy, by happy chance he fell upon an estimable work[2] of which a careful perusal would almost make us think that nature really had an embryo cycle or wheel method in view when we were planned for legs. The great interest attaching to the above-mentioned work arises from the fact that the book was written before the cycle was at all broadly known to be of any assistance to the self-propulsion of man under any circumstances. This work must be read to be appreciated. I give some quotations, the application of which shows that, in the minds of some, the Creator had an idea of a wheel within a wheel; in short, that nature seemed to want to roll.
Let us quote from page 51, “Animal Locomotion.”
“When the right leg is flexed and elevated, it rotates upon its iliac portion of the trunk in a forward direction to form the arch of a circle which is the converse of that formed by the right foot, if the arcs alternately supplied by the right foot and the trunk are placed in opposition, a more or less perfect circle is produced, and thus it is that the locomotion of animals is approximated to the wheel in mechanics.”