In its steering arrangements and mode of propulsion, its construction is similar to that of the bicycle. The rear wheels are large and light; the fore wheel is smaller, and serves to guide the machine, being acted upon by means of the steering bar or handle, which causes it to bend in the direction indicated by the rider. The pedals are attached to the front wheel, and are shaped like slippers, which facilitates the movement of the legs, and at the same time admits of the feet being disengaged simultaneously. The movement required to propel this machine is a natural one, does not produce unusual fatigue, and is analogous to that of walking. The larger three-wheeled velocipedes have a lever which follows the line of the eccentrics attached to the pedals, and fits on to the axles. By assisting the movement of this lever, the speed of the vehicle is considerably increased, and a simple pressure against it checks the rotary motion of the wheel, and stops the progress of the machine. This lever is, in fact, both a means of impulsion and a brake. As this vehicle is chiefly patronized by the fair sex, the seat is more commodious than that of the bicycle; having sides and back of wicker, and a horse-hair cushion. The tricycle is simply a hack, while the bicycle is a blooded horse that fully demonstrates the “poetry of motion.” The tricycle is easier to guide, and safer to ride than the two-wheeled machine; there is however more friction, and its speed is much less rapid. It has, thus far, been found impossible to construct a three-wheeler with the pedal method of propulsion, that could compete with the bicycle in speed or pleasure of driving. Large wheels are necessary for speed. If a guiding wheel be applied to a tricycle of this kind large enough to run rapidly on the road, and to counterbalance the size of the other wheels, it would be unsteady of motion; the rider would be apt to be thrown headlong at any jar, and the whole machine would be rendered unsafe. Many of the larger manufacturers have built the tricycle to some extent. Most of them have discontinued their make, finding it unprofitable, and that the machine gave but little satisfaction. The Bradford Brothers of New York City obtained a patent, and entered largely into the business, at considerable expense. They, however, soon stopped the manufacture, and gave exclusive attention to their four-wheeled machines. The three-wheeled velocipedes of Messrs. Kimball Brothers, Boston, seem to be as popular as any in the market; but the sale is mostly local, and but few of them are manufactured. Various inventors have endeavored to obtain power, by additions to the gearings, in the shape of spring wheels and levers, but with little success. Others have applied the principle of the crank to be turned by the hand, using the hand for steering purposes.