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Typo: A Monthly Newspaper and Literary Review, Volume 1

[technical innovations in printing]

A mechanical feeding attachment to printing machines has long been a desideratum. The pneumatic apparatus devised some years ago was costly, and failed to come into general use. A machine has been perfected in America which feeds a sheet at a time more quickly and efficiently than can be done by hand. It is readily adjusted to different sizes of paper. The apparatus has three iron fingers, one of which is always on the pile of paper; and the action of the hand-feeder is closely imitated. The machine is in practical and profitable use in paper-mills and ruling establishments in the United States, and attached to an ordinary cylinder printing machine, renders it entirely automatic.

A Russian inventor has by a very ingenious process extended the art of photo-etching to boxwood blocks. The block is boiled in two separate solutions, by which the pores are filled with insoluble carbonate of copper. It is then polished on the surface, coated with a solution of asphalt on the back and sides, and the face is covered with a gelatine film. The photograph is then taken on the block; and the soluble portions of the gelatine having been washed out, the remaining surface is coated with asphalt. The block is then placed in strong nitric acid for an hour, and afterwards for the same period in sulphuric acid, which changes the unprotected portions into nitro-cellulose. All that remains now to do is to dry the block, to brush it with a hard brush, when the unprotected portions come off as a green powder, and to remove the asphalt with benzine.