Book Description

Excerpt from A Dictionary of Terms Used in Printing A printed page, an engraving, or a bank note may be exactly copied by this invention. Moisten the printed paper with dilute phosphoric acid, lay it face downwards on a clean sheet of Zinc, and put it in a press for a short time. The acid of the unprinted part etches the zinc beneath, while the printed part sets off on the zinc, and thus produces a reverse copy of the printing. Wash the plate with an acid solution of gum, and it will be ready for use. The plate may now be treated as the stone in Lithographic Printing first damped, and then rolled. The affinity of the ink to the letters already set off on the plate, and the repulsion of the other parts of the plate, cause the lines of the device to take the ink, but the other parts remain clean, the printing then follows. See Lithography. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.