As so far described the presses were worked by hand power. An important step in the advancement of this art was made by the introduction of _power presses_ worked by steam. These arranged the type on the surface of a cylinder. Probably the earliest form of rotary cylinder press is that invented by Nicholson, British Pat. No. 1,748 of 1790. Its main features are described as follows: “The types, being rubbed or scraped narrower toward the foot, were to be fixed radially upon a cylinder. This cylinder with its type was to revolve in gear with another cylinder covered with soft leather (the impression cylinder), and the type received its ink from another cylinder, to which the inking apparatus was applied. The paper was impressed by passing between the type and the impression cylinder.” The first practical success, however, in rotary steam presses was achieved by König, a German, who in 1814 set up for the _London Times_ two machines, by which that newspaper was printed at the rate of 1,100 impressions per hour. He obtained British Pat. No. 3,321 of 1810, No. 3,496 of 1811, No. 3,725 of 1813, and No. 3,868 of 1814. König’s machine was in 1827 succeeded by that of Applegath and Cowper, which was simpler and more rapid. Many improvements upon the methods for handling the paper were subsequently devised, and double cylinder presses were made which were able to print 4,000 sheets an hour. In 1845 the firm of R. Hoe & Co., which had already been for years engaged in the manufacture of printing presses, brought out the Hoe Type Revolving Machine. The first one of these was placed in the office of the _Philadelphia Ledger_ in 1846, and had four impression cylinders, printing 8,000 papers per hour. The constantly increasing circulation of newspapers, however, continued to make insatiable demands for more rapid work, and to meet this demand the Hoe company in 1871 brought out their continuous web press, in which the paper was furnished to the machine in the form of a roll, and after being printed was separated into sheets. This principle of action gave promise of unlimited speed, and required important reorganization in all parts of the machine. To meet these conditions of increased speed more rapid drying ink had to be produced to prevent blurring, paper of uniform quality and strength had to be made, means had to be devised for printing the opposite side of the web, and severing devices for cutting the web into sheets were needed, but perhaps the most important feature was the device called a gathering and delivering cylinder, whereby the papers could be gathered and disposed of as fast as they could be printed, and much faster than human hands could work. This was the invention of Stephen D. Tucker, and it is the mechanism upon which the speed of the modern press depends, for it would obviously be useless to print papers faster than they could be taken from the machine in proper condition. Many patents were taken by Messrs. Hoe & Tucker covering