History of the Typewriter

— 72 — held its alignment perfectly. An examination of the type-bar joints at the end of that time showed practically no wear or play. A further very exacting test was then given them, the type-bars being set to work by machinery, and being made to strike upwards of two million blows. The test was regarded as the equivalent of three years’ very hard work, and again no wear was perceived. Fig. 56 After this it was decided to introduce ball-bearings wherever they could be introduced to advantage, and as a result the makers now say that the machine “ bristles with balls all over.” The carriage of the Densmore is exceedingly light, and moves speedily with very little tension. Again, ball- bearings have been brought into use, and this aids in its light running powers. The carriage does not lift, but the platen is made to swing forward, so that the writing is brought into sight in a moment. The platen is so made that it can be lifted off the machine, carrying with it an unfinished piece of work, and another platen substituted for any special requirement, such as stencil cutting, mani- folding, etc. There is a graduated scale on the paper table, which will permit the paper always being fed in at the same relative position, thus securing absolutely even margins. Facilities afforded for throwing the line spacing out of gear, and the pressure of the feed roll can be lightened in order to permit of the adjustment of paper, or the insertion of a number of thicknesses for carbon work. The feed roll automatically adjusts itself by the mere act of swinging the platen into its normal position.