Of the three forms of printing attention has been given thus far only to the leading branch of the art, which is _type printing_, or “_letter press_,” as it is called, in which the characters are raised in relief and receive ink on their raised surfaces only. A second branch of the art is _plate printing_, in which the lines and characters are engraved in intaglio in a plate, and which, being covered with ink, and the surface of the plate wiped clean, leaves the ink in the undercuts, which is taken up by the paper when pressure is applied through a roller. Plate printing is a very old art, the plate printing press having been ascribed to Tomasso Finiguerra, of Florence, in 1460. The reciprocating table bearing the engraved plate, and the superposed pressure roller turned by hand through its long radial arms, is an ancient and familiar form of press which has been in use for many years. This method of printing finds application in fine line engraving in works of art, card invitations, and bank note engraving. Very ingenious automatic machines have been invented and were in use a few years ago by the United States Government for printing its bank notes, but have since been displaced by the old hand machines. To the credit of the machine, it should be said, that it was from no fault in the machine that this retrograde step was taken, but rather the disfavor of the labor organizations. _Lithography_ is another and quite important branch of the printing art, in which the lines and characters are drawn upon stone with a kind of oily ink to which printers’ ink will adhere, while it is repelled from the other moistened surfaces of the stone. Lithography was invented in 1798 by Alois Senefelder, of Munich. It finds its greatest application in artistic and fanciful work in inks of various colors, and its development into chromo-lithography in the Nineteenth Century has grown into a fine art. Our beautifully colored chromos, prints, labels, maps, etc., are made by this process. A more recent and quite important development of this art is photo-lithography, which will be more fully considered under photography. Many collateral branches of the printing art are interesting in their development, such as calico printing, the printing of wall papers, of oil cloth, printing for the blind, book binding, type founding, and folding and addressing machines, but lack of space forbids more than a casual mention.