History of the Typewriter

— 44 — proceeded clown the side, beneath the key-levers, then up the other side, and again over the top. Each key as depressed caused the cylinder, by pawls, G, and ratchet wheels, F, to partly revolve ; at the end of the line the cylinder shifted along the axis rod for the line-spacing, the rack, I, engaging with a spring flange, H, on the cylinder, thereby acting as a cam. Incident with this movement the clamp, E, rotated quickly across the printing point, the ratchet wheels, F, having a slip-space for the purpose. The weighted cord passed over three pulley wheels, two of which are seen at K and L. These pulley wheels imparted the requisite power for winding the ribbon and rotating the cylinder for letter spacing and line spacing. The next diagram illustrates one of Sholes’s later attempts, probably about the year 1870 ; it differs chiefly in the design of the framework and the adoption of the well-known keyboard. Fig. 29 It would appear to be about this time that the late Mr. G. W. N. Yost was invited to Milwaukee to inspect the then last machine made. Up to that time, some fifty machines had been made, mostly in country blacksmith style, at an average cost of about fifty pounds per machine. Mr. Yost, with the trained eye of a skilled mechanic, saw at once where the defects were. He suggested certain minor alterations and improvements, but he pointed out, and urged the absolute importance of such an instrument being made under the most skilful supervision. He indicated precisely how necessary it was that the most perfect fit should be obtained for the various parts, how skilfully each part would have to be adjusted, how finely the various working parts would have to be made. He drew attention to the fact that only the most perfectly equipped factory, having all the latest forms of machinery procurable, could