Page:Popular Science Monthly Volume 46.djvu/625

Rh the roll. Even the finest and faintest scratch of a diamond point can be taken up this way and retransferred to another piece of steel and printed to the paper, so little is lost in the operation.

The roll is now put through the same process of hardening previously used on the die, and we are then prepared to make a great many duplicates of the original. One hundred or more facsimiles of the die can be made in less time than it took to produce the original. For instance, it takes a picture engraver about six weeks to engrave a portrait like that of Martha Washington on the left of the one-dollar United States note, and it can be reproduced in fifteen minutes by means of the transfer press and a roll taken from the original die.

Imagine, if you can, the work it would be to engrave by hand the two hundred postage stamps that are usually put on the plate from which they are printed, or the forty or fifty coupons of a bond. An endless job, you say, and yet that is just what would have to be done if it were not for the transfer press. And not only is it possible to thus readily multiply facsimiles of the original, but the reproductions are exact in every respect and detail, excepting the almost imperceptible loss in the process, which is natural and unavoidable.

Transferers work from a paper model made with prints from the original dies, which are very carefully put together in such a way as will give a very good idea of the effect of the finished work. These models are also submitted to and accepted by the party for whom the work is to be done.

After the plate is transferred it shows hollows around the work, made by the pressure of the roll, which must be brought back to a flat surface again; otherwise a clean proof could not be taken. These hollows are flattened by first carefully marking the outline of the work on the back of the plate, by means of "calipers" made for the purpose, then laying the face of the plate on a polished hardened-steel anvil and hammering around the outline. All scratches, guide lines, and marks that have been used by the transferer are then removed by burnishing the surface, and the plate is ready for the engraver's hands, for there is always some flourishing and finishing to be done before the plate is ready for the printing press.

Plate printing is the opposite of block or woodcut printing in this respect: The line that is to print the color is cut into and below the surface in plate work, and may be so fine that it can not be seen without the aid of a strong magnifier, and yet print perfectly clear and unbroken, while in block the line is left standing and must have some appreciable thickness. For this reason wood engraving can never be as delicate as plate, for it could not