SCIENCE IN THE INDUSTRIAL WORLD 



office of the Philadelphia Ledger and soon demonstrated 

 that a revolution in newspaper presses was at hand. 



The actual output of this, and other similar machines, 

 was limited to the number of sheets of paper that 

 could be fed to it by hand about two thousand sheets 

 per hour just as in the case of the flat type-bed machine 

 where the paper is carried on a cylinder. But the great 

 advantage lay in the fact that several paper-bearing 

 cylinders could be acted upon at each revolution of the 

 type-bearing cylinder, each one fed by an operator 

 at the rate of two thousand sheets an hour. A single- 

 cylinder machine could produce two thousand sheets; 

 but the same cylinder revolving at the same speed could 

 be made to increase its capacity two thousand sheets 

 for every additional cylinder and feeder. As many 

 as ten of these paper-carrying cylinders were grouped 

 around type cylinders, the output of such a machine 

 being twenty thousand papers an hour. By means of 

 these "ten-cylinder rotary" presses the newspapers 

 were, for the first time, able to meet the demands of 

 their rapidly increasing circulations, and the day of the 

 "ten-minute edition" was in sight. 



Before these rotary machines had been perfected, 

 however, another valuable discovery had been made. 

 This was a method of casting stereotype plates on a 

 curve. By this method it was possible to take duplicate 

 impressions of the type, cast them as solid pieces of 

 metal, and use them on the rotary presses just as the 

 types themselves are used. In this manner a number of 

 presses could be supplied with stereotypes made from a 

 single setting of type, and requiring only the additional 



