Page:The New International Encyclopædia 1st ed. v. 02.djvu/548

BANK-BILLS. are in conflict. Consult the authorities referred to under the title. BANK DIS'COUNT. See. BANK HOL'IDAYS. In England Sunday, Christmas Day, Good Friday, Easter Monday, the Monday in Whitsun Week, the first Monday in August, the 26th of December (called Boxing Day), or, if that day is Sunday, the 27th, or any day appointed by Order in Council in place of either of the last four days, and any day appointed by royal proclamation as a public fast or thanksgiving day. Banks are to be kept closed on such days, and bills and notes payable on any of these days are declared payable on the next following business day. In this country every (q.v.) is, as a rule, a bank holiday: and negotiable paper payable on such day, without grace, is payable the next business day. If it is entitled to days of grace (see ), and the last day of grace falls on a public holiday, it is payable on the last preceding day, in the absence of a statute varying this rule. BANK-NOTES, . The chief aim in the manufacture of bank-notes is to render counterfeiting impossible, or, at least, easy of detection. This is usually accomplished by peculiarity of paper, design, ink, and printing, or by a combination of these means. English bank-notes are printed with the blackest and most indelible ink on a peculiar kind of handmade paper bearing a distinctive water-mark. (See .) As a further security against counterfeiting, a self-registering machine is used for impressing upon the note a mark known only to the Bank of England officials. The various banks in Scotland issue bank-notes of a paper much like that used in England, but usually they employ several colors of ink besides black in printing them. Until 1837, copper-plate printing was employed for English bank-notes: and from 1837 to 1855 the method of Perkins Heath for the reproduction of designs by the mill and die process was employed. In this process the design was engraved on a soft steel plate, which was then hardened, and the pattern transferred by pressure to a soft steel roller, where, of course, it appeared in relief. The roller of the mill was then hardened, and used to reproduce the pattern on the plate from which the printing was actually done. The great advantage of this method was that a large number of plates of the same pattern could be produced with comparative ease. In 1855 electrotype printing was introduced by Smee and the mechanical officials of the Bank of England, and since that time all English bank-notes have been printed from the electrotype plates.

The extensive use of treasury notes or other forms of paper currency in the United States has led the Bureau of Engraving and Printing of the Treasury Department at Washington to develop methods for producing notes which should not only be difficult to counterfeit, but which should be legible, durable, and artistic in design. In many instances, celebrated artists have been engaged to furnish designs for notes; but more generally the designs have been prepared by the artists belonging to the Bureau. Whoever the designer may have been, the work of transferring the design to the plate and the entire mechanical production of the note, except the manufacture of the paper, is carried out by the Bureau. The paper is made by a private concern only for the Government, the process of manufacture being patented. The principal ingredients of the paper are linen and cotton fibre, into which threads of silk are introduced in such a manner as to be visible in the printed note. The process of manufacture, as carried on at the Bureau of Engraving and Printing, is as follows: The design of the note, including all the lettering and devices thereof, upon a sheet of the required form, being in the hands of the workmen, they first proceed to make the die. A plate of soft, highly polished steel is selected, and upon it is sketched the design, or such portions of it as are of the same color, if more than one tint is to be used in printing. A separate die is needed for every shade used. This is then carefully engraved. It will be understood that, unlike the method of wood-engraving, the lines which take the ink are cut into the plate instead of being raised above its surface. The engraver is limited to such parts of the work as can be done by hand; other portions, such as the scrolls and elaborate tracery, are done entirely by machinery. The principal apparatus used is a complicated piece of mechanism, which actuates a plate to which the steel for the die is attached and caused to press against a diamond point. Perfectly true and delicate lines are thus cut into the metal, making figures technically termed 'cycloid rosettes.' The machine, in theory, somewhat resembles a kaleidoscope, as it requires to be set by accurate pointers and dials to some special figure, which, when the combination is changed, can never be reproduced. One of these instruments is in use, and its work, together with that of the geometrical lathes, can be readily recognized on the national currency.

The die, being complete, is ready for the transfer process. Postage stamps, for instance, are made in sheets of two hundred, so that the die must be transferred that number of times on a single plate. It is first case-hardened, and then put face up, in a press which is made with a combination of levers actuated by the foot, so as to give the tremendous pressure of twenty-one tons on a single line. A cylinder or 'roll' of soft steel is, by careful gauging, placed so as to rest directly over the face of the die, and, at the same time, is so arranged as to revolve easily along its surface even when under the full weight. The pressure is then applied, with the result of forcing the soft steel of the roll into the lines of the engraving, so that when complete, the periphery of the cylinder shows an exact reproduction of the face of the die, only the lines sunk on the die are now raised on the roll. Next, the cylinder is case-hardened. Then the plate— soft steel again— to be used for the final printing is placed in the press, and the roll is arranged above it. Now the cylinder leaves its impression on the plate, the hard steel of the raised lines cutting deep into the surface, so that a precise duplicate of the original die is obtained. This is repeated as many times as there are to be repetitions of the stamp or note on the single plate, which is then ready for use.

The ink for printing is made on the spot. In a large room are ten or a dozen paint-mills, which are busily grinding the colors and oil together. Two large ones are filled with green