“The invention consists in the use of sliding cranks, which project from both sides of the shaft. “One end of each crank is guided by a fixed eccentric groove or track, in such manner that the crank-pin is moved away from the shaft as long as the power is applied to the same by the foot. When the power is not required, on the return stroke, the crank-pin is drawn close to the shaft, and thus, without describing a large circle, the crank-lever is made longer than usual, when required. “Thus, a twelve-inch crank-bar can produce a nine- or ten-inch working-crank, while the crank-pin describes a circle of not more than twelve inches diameter. Heretofore, a twelve-inch circle was described by a six-inch crank. Greater leverage and power are thus obtained by my invention. “+Edwd. A. Lewis.+” * * * * * This is one of the most deceptive schemes in cycle history; if it worked as the inventor implies, we should have perpetual motion in fact. A man cannot transmit power to the wheel while the crank is coming up, except the little he can get by ankle-motion. A close examination will show that, whereas the crank is longer, the man has a proportionally less number of degrees through which he can drive it. Time, as well as force, enters into the problem of driving a bicycle; the time is equal to the number of degrees the crank travels through; here a man only has one-third, or less, of the circle, through which he has any power to turn the wheel. It is of no advantage to have one-third longer leverage if you have one-third, or over, less time, or number of degrees, to transmit power. The enormous mistake of this inventor consists in the fact that it would actually be better if he transmitted his power through the arc of short, rather than that of the long, leverage. If you do not increase your vertical amplitude, or resultant, depend upon it you cannot increase your power unless, at least, you push through a comparable number of degrees at better advantage. [Illustration: F. H. C. Mey, of Buffalo. Velocipede. No. 109,644. Patented November 29, 1870.] “_To all whom it may concern_: “Be it known that I, +F. H. C. Mey+, of Buffalo, in the county of Erie and State of New York, have invented a new and improved Dog-Power Vehicle. “This invention relates to vehicles which move from place to place on roads, pavements, etc., and consists in an improved construction thereof. “_A_ is the driving-wheel, which in this instance is in the front of a vehicle having three wheels, but may be in the rear, if preferred, or in any other location. “The animals being placed in this tread-rim, as represented in Fig. 2, and caused to work, will impart motion to the wheel and to the vehicle, as will be clearly understood. “Having thus described my invention, “I claim as new, and desire to secure by Letters Patent,—