The chief objections to the bicycle, then, are the liability of the rider to go over the handles, the impossibility of stopping very quickly, and the inability to remain at rest or go backward, and the difficulty of learning. The first two of these are, to a large extent, overcome in the safety bicycles, but not without the introduction of what is in comparison a certain degree of complication, or without the loss of the whole of the grace or elegance of the bicycle. On almost all of these safety bicycles the rider is better placed than on the unmodified bicycle, but though safer, I do not think bicyclists find them complete in speed, though, no doubt, they are superior in that respect to the tricycle. Though they do not allow the rider to stop without dismounting, the fatigue resulting from this cause is less than it is with a bicycle, owing to the fact that with the small machines the rider has so small a distance to climb. Of these machines, the Extraordinary leaves the rider high up in the air on a full-sized wheel, but places him further back and more over the pedals. The motion of these is peculiar, being not circular, but oval, a form which has certain advantages. In the Sun and Planet and Kangaroo bicycles a small wheel is "geared up," that is, is made to turn faster than the pedals, so as to avoid the very rapid pedaling which is necessary to obtain an ordinary amount of speed out of a small wheel. In each of these the pedals move in a circular path, and their appearance is in consequence less peculiar than that of the Facile, which, in this respect, does not compare favorably with any good machine. The pedal motion on the Facile is merely reciprocating. Riders of machines where circular motion is employed, among them myself, do not believe that this reciprocating motion can be so good as circular, but I understand that this view is not held by those who are used to it. Of course, the harmonic motion of the Facile pedal is superior to the equable reciprocating motion employed in some machines where speed is an object, especially with small wheels. If I have overlooked anything typical in the modified bicycle class, I hope some one will afterward supply the omission, and point out any peculiarities or advantages. That very peculiar machine, the center-cycle, seems to combine many of the advantages of the bicycle and tricycle. On it the rider can remain at rest, or can move backward; he can travel at any speed round curves without an upset being possible; he can ride over brickbats, or obstructions, not only without being upset, but, if going slowly, without even touching them. As this machine is very little known, a few words of explanation may be interesting.