CRZENIAM. During the civil war in America from 1861 to 1865, the immense 'expenditure of the U. S. government led to the printing of an unprecedented number of hank-notes, bonds, and currency papers of various kinds. These documents, from the color presented by them, or some of them, obtained the name of greenbacks, a designation which became almost as familiarly used in congress as among the general public. At first., the manufacture of these notes taxed the resources of the government in a very embarrassing way; and there was ample reason to suspect that forged notes and bonds were abundantly in circulation; but, by degrees, a fine and large establishment was arganized at Washington, under the immediate control of the secretary of the treasury. Trt this establishment, everything was conducted from first to last; rags, fibers, plates of :Mel, and colors were taken in, and finished notes were sent out. It was only under very tare circumstances that strangers were admitted to view the operations; but one such oCCaSiOn, in 1S64, led to a general description of the place being given in most of tho newspapers, from which it was copied into some of the English scientific journals.
Speaking of the establishment as it was in 1804, and not touching upon any of the modifications which may since have been introduced, there were distinct and separate departments for mechanical repairs, paper-making, ink-making, paper-wetting, plate engraving, printing, numbering and denominating, and cutting. In the paper-mill, all the paper for the greenbacks was made, with a degree of scrupulous attention and uniformity that cannot always be insured in a private establishment. It was necessary to have a paper that would wear well, would not split easily, and would be sufficiently non-photographic to baffle a forger. Dr. Gwynn made many experiments, with a view to intain excellence on these points; and at length he produced a kind of paper nearly as strong as parchment and as smooth as satin. The nature of the material was known only to himself and the government. There was a fiber in the paper, quite molded or felted into its substance, which could not be photographed without discoloring the sheet to which it was transferred, giving it the appearance of a coarse, black spider web, which would instantly have betrayed the forgery. In another department, the ink was made by means of grinding-machines, one for each of the several colors used in the various kinds of notes and bonds. While these operations of paper-making and ink making were in progress, the engraving of the plates was conducted in another depart ment. The steel-plates were engraved with the most minute and intricate devices which the hand and the eye of the artist could execute: it mattered little what device was selected, provided it were difficult for a forger to imitate. One particular note was, in its main features, an engraved copy of a picture in the rotunda of the capitol at Washing ton; and the engraving is said to have occupied a whole year to execute. All the devices,
of whatever kind, were made to co-operate with delicate water-lines in the paper, to render forgery difficult. As the plates were costly to engrave, and fitted to yield only a certain (though large) number of impressions each, a mode of multiplication was adopted which had for many years been largely used in England. The processes were thus con nected: 1. The engraver executed the design on a smooth plate of soft steel. 2. The plate was hardened by well-known processes of heating and cooling. 3. A roller of soft steel was pressed with immense force over the hardened plate, and took upon its surface the device in Mid'• as the roller was equal in length to the length of the plate, and equal in circumference to its breadth, the curved surface exactly took in the whole of the device. 4. The roller was hardened. 5. The hardened roller was used as a matrix to produce any number of plates in soft steel, which had the device in intaglio, like the original plate. 6. These plates, when hardened, were used to print from.
The paper, the ink, and the plates being thus prepared, all was ready for the printing. In the earlier period of the working of the establishment, presses were used such as arc generally employed by copperplate printers ; each press attended by a woman to place and remove the paper, and a man to manage the inking an time pressure ; but after wards, a large room was filled with hydraulic printing-presses, which conducted the operations much more rapidly. The notes, as fast as printed, were interleaved with sheets of thin brown paper, to prevent blurring. In numbering and denominating the notes, a yellow mordant was employed, of such kind that the note could not be photographed without producing a black impression from the yellow portion. The numbering-machine was worked by a treadle ; there were six disks with figures on their edges, and they so acted on each other by means of ratchets, that they could print any number from 1 to 999,999. For consecutive numbering, the machine adjusted its own figures after each printing. The notes were usually printed four on a sheet. and were afterwards severed and trimmed by a cutting-machiae, which made them all precisely equal in size and shape. So complete was the cheek established in all the operations, that "not even a blank sheet," said a narrator, " much less a printed one, is passed from one hand to another without being counted and receipted for ; end unless there is col lusion from one to another in every process through which the paper has to pass before it is finished, there cannot be an over-issue. The paper is issued from one room, and is re-issued from that room sixteen or eighteen times before it is put into circulation ; being counted, charged, and receipted for each time, and recounted, recharged, and re-ref-dined for through each process that it passes after leaving that room." For the English system, see I314.-.Noti.:s.