33. Within the present century, great improvements have been made in the printing business generally, especially in the presses, and in the means of applying the ink. In the old Ramage press, the power was derived from a screw which was moved by a lever; but, in those by several late inventors, from an accumulation of levers.
34. In 1814, printing by machinery was commenced in London, and rollers became necessary for inking the forms. These were made of molasses, glue, and tar, in proportions to suit the temperature of the weather. From these originated composition balls in the following year, and in 1819, hand rollers. Formerly the ink was applied by means of pelt balls stuffed with wool.
35. The power-press first used in this country, was invented, in 1823, by Mr. Treadwell, a scientific mechanic, of Boston, who was originally a watch-maker by trade. It acts on the same principle with the hand press, and is equal to three of these of the best construction. Daniel Fanshaw, who first applied steam to printing in the United States, introduced several of these presses into New-York, in 1826. Messrs. Adams and Tufts, of Boston, have each invented a power-press which act on the same principle with Mr. Treadwell's.
36. The presses noticed in the preceding paragraph, are used chiefly in printing books and periodicals requiring moderate speed in their production. But they do not answer the purposes of the daily press in large cities, where from twenty thousand to sixty thousand impressions of a single paper are required every day. To supply this immense demand of the public was the original aim of the inventors of power-presses in England. The first attempt to construct a printing machine was made, in 1790, by William Nicholson, of London; but his machine was never brought into use. The next attempt was made by Mr. Konig, an ingenious German, who but partially succeeded. The first really useful machine was constructed by Messrs. Applegate and Cowper.
37. The machines used in this country are modifications of that originally invented by Mr. Napier, of England. The paper is brought in contact with the form of types by means of a cylinder, while the form is passing underneath it. The press is constructed with one or two cylinders. A double cylinder press will give from 4000 to 6000 impressions an hour. The improvements on this press were made by Robert Hoe & Co., who have permitted Mr. Napier to introduce them into his press in England.
THE TYPE-FOUNDER.
1. The types cast by the type-founder are oblong square pieces of metal, each having, on one end of it, a letter or character, in relief. The metal of which these important instruments are composed, is commonly an alloy consisting principally of lead and antimony, in the proportion of about five parts of the former to one of the latter. This alloy melts at a low temperature, and receives and retains with accuracy the shape of the mould. Several hundred pounds of type-metal are prepared at a time, and cast into bars filled with notches, that they may be easily broken into pieces, when about to be applied to use.