History of the Typewriter

—288— Fig. 208. likely to prove a great convenience. This machine will make clear carbon and stencil duplicate copies, and is particularly desirable for writing cards and labels. Wirt’s Typewriter. This machine is designed to write music as well as ordinary writing. In order to obtain this result 280 musical signs and letters are engraved upon a prismatic cylinder, and these can be used by means of twenty-eight direct-acting keys, shift-keys, and a shift- drum, which latter is also operated in the newer type of instruments by means of a shift-key. The type cylinder has the form of a sixteen-cornered prism, is mounted on a horizontal axle, and can be later- ally moved on the same. It is also mounted on a slide by means of two supports, which are connected with two springs which make the drum return automatically to its central position after having moved sideways. The drum is therefore adapted to two distinct motions, the one being rotary and the other a sliding motion. When one of the keys is depressed the cylinder sets itself so that the sign which one intends to write comes opposite the striker, which presses the paper and the ink ribbon against the cylinder. The distance to which the cylinder will slide on the axle is set by pins counter-balanced by spiral springs, the pins stopping the movement of the shift-lever by entering into holes bored through the slide bar. When music is being written the cylinder will not only write the sign, but also