Page 52. “Another drawback to great speed in man (as distinguished from animals) is, ... part of the power which should move (serve as a motive power) ... is dedicated to supporting the trunk.” Now, in the cycle method we support the trunk all right, but should apparently make more use of the arms,—inventors take notice. Page 56. “In this respect the human limbs, when allowed to _oscillate_, exactly resemble a _pendulum_.” Here is the trouble with nature; there is too much oscillation instead of continuous rotation; nature does not go far enough. Page 58. “The trunk also _rotates_ in a forward direction on the foot which is placed on the ground for the time being; the _rotation_ begins at the heel and terminates at the toes.” Thus the rotation is all right so far as it goes. Page 60. “The right side of the trunk has now reached its highest level and is in the act of _rolling_ over the right foot.” Hence see the effort of nature to roll. Page 61. “In traversing a given distance in a given time a tall man will take fewer steps than a short man, in the same way that a large _wheel_ will make fewer revolutions in travelling over a given space than a smaller one. The nave of a large _wheel_ corresponds to the ilio-femoral articulation (hip-joint) of the tall man, the _spokes_ to his legs, and portions of the _rim_ to his feet.” We thank nature very much for this suggestion of the wheel; without it perhaps we should never have conceived of the veritable wheel itself. I also find from another work:[3] “Living beings have frequently and in every age been compared to machines, but it is only in the present day that the bearing and the justice of this comparison is fully comprehensible.” Page 67. “One might find in the animal organism many other appliances the arrangement of which _resembles_ that of _machines_ invented by man.” Page 91. “Let us examine from this point of view the articulation in the foot of man: we see in the tibio-tarsal articulation a _curvature_ of small _radius_.” Page 112. “In addition to this the body is inclined and drawn up again; at each movement of one of the legs it _revolves_ on a pivot.” And so on in all works on animal locomotion will ever be found a continual reference to radius, roundness, and rolling. These quotations show that while we must acknowledge that the fundamental principles involved in the cycle were anticipated, to a certain extent, by nature, we may yet take great credit upon ourselves for developing the new or improved method to such a perfect and useful degree.