History of the Typewriter

-143- The Hammond is known as a typewheel, as dis- tinguished from a type-bar machine. In the latter the type is attached at the ends of a series of bars, which are pivoted in a circular frame, each bar making its own impression on the paper. In the Hammond the position is reversed, the type being cast in one integral piece, called the shuttle, which is oscillated upon the outer edge of an annular ring, called the anvil, the desired letter being brought into position in front of a hammer, which, under the impulse of a spring, drives the paper against the type. The primary object of this arrangement is to secure perfect alignment and a uniform impression. Fig. To enable the operator to see his work, the circular frame surrounding the anvil, which holds the type shield and the ribbon, is arranged so that it can be temporarily depressed, returning to position again on being released. In this way the work is kept in sight, and the lifting of the body of the machine is avoided.