Part 2 (1/2)
[Ill.u.s.tration: Stamp, ”Congo”, 25 centimes]
[Ill.u.s.tration: Stamp, ”British Guayana”, 1897, 1 cent]
[Ill.u.s.tration: Stamp, ”British Guayana”, 1897, 2 cents]
[Ill.u.s.tration: Stamp, ”New Zealand”, 5 pence]
[Ill.u.s.tration: Stamp, ”Toga”, 3 d.]
[Ill.u.s.tration: Stamp]
Crowns and post-horns figure on many stamps and both are significant of the authority and purpose of these seemingly trifling bits of paper. An interesting combination of these two emblems is found on one of the newspaper stamps of Hungary. In this case the crown is not merely a creation of the artist's fancy but the historic crown of Saint Stephen, the ”iron crown of Hungary,” so called because it has within its rim an iron band said to be made from one of the nails of the cross.
In all these subjects of thought I have mentioned only a few examples under each head. The number might be multiplied many times, did I not fear to weary you.
But, turning from the purely pictorial side, let us consider the material side of stamps and the various methods employed in producing them. The design having been selected, it becomes necessary to reproduce it in some form suitable for making stamps in large quant.i.ties. In a general way we may divide stamp printing into two cla.s.ses: printing from metal plates and printing from stone, or lithography. The first cla.s.s contains two grand sub-divisions. In the first of these sub-divisions the lines to be reproduced are sunken below the surface of the plate.
This is known as _taille douce_ or line engraving. It is also called copper plate and steel engraving. The copper plates for our visiting cards are familiar examples of this style of work and our national paper currency presents very beautiful and elaborate results of the process.
The second sub-division is known as typography or surface printing. As its name indicates, the lines to be reproduced are at the surface of the plate, the other parts being cut away. A newspaper is an example of typographical printing, the term being applied to designs made up from type, as well as to specially prepared plates.
I need not suggest to you how wide a field for thought and exploration this subject of engraving opens to us, leading as it does directly into the world of books, pictures and art. But at present we must confine ourselves to the subject as applied to postage stamps, save for a brief consideration of its origin and history.
The art of engraving owes its origin to the Florentine goldsmiths of the fifteenth century. They were accustomed to ornament their work with incised lines which were filled with black enamel. A design thus filled with enamel was called a _niello_, a derivative of the word _nigellum_ (the most black). The bra.s.s and nickel signs with black letters, which we find at the doors of business houses, are modern forms of _nielli_.
While making a _niello_, the artist naturally wished to see how the work was progressing and if any alterations were required. It was not desirable to put the enamel in the design because it was difficult to remove. To avoid this an impression of the work was taken in clay, from which a sulphur cast was made. The lines of the cast were filled with lamp black. Thus a copy of the work was obtained which reproduced its coloring and showed the condition of the engraving. A more simple process was discovered later. This consisted in filling the lines of the engraving with a thick ink and pressing a sheet of damp paper against them. Sufficient pressure was used to force the paper into the lines and take up the ink on its surface. This was the beginning of line engraving and plate printing. The process was at first employed for the preservation and duplicating of designs for goldsmith's engraving and afterwards for the sake of the work itself. It was not until the next century that the process a.s.sumed a leading place in the world of art. If it were not going too far away from our subject we might study the early engravers and their work with much profit and entertainment. But it is our purpose to consider the subject only so far as it applies to postage stamps.
Until the early part of the present century copper was practically the only metal used for engraving. Only a limited number of impressions can be taken from a copper plate because it wears rapidly, and it is not suited to such work as the production of postage stamps. About 1830 the way was found to make steel of sufficient softness and fineness of grain to be available for engraving. To-day annealed steel is almost exclusively used for this purpose. Annealed steel is steel which has been softened without being decarbonized. The surface is carefully ground and polished to a mirror-like brightness. Any work which is to be reproduced many times, such as postage stamps and parts of bank-notes, is made on small pies of steel called dies.
If the design to be used is in the shape of a drawing or engraving, a sheet of gelatin may be laid over it and the outlines traced with a sharp-pointed instrument. More often a photograph is taken on a ferrotype plate and the outlines scratched into the plate. These outlines are filled with vermilion. A piece of paper is then laid on the plate and the two pa.s.sed through a hand-press. This is called ”pulling”
an impression. While the ink of the impression is still moist it is sprinkled with powdered vermilion to strengthen the lines. The block of steel is then covered with an etching ground (a composition of asphaltum, wax, resin and ether) and the impression is transferred to this. The outlines are cut through the etching ground and bitten into the steel with acid. The coating is then removed from the block and the artist proceeds with the engraving. The mechanical details and various methods of engraving are highly interesting but time will not permit their discussion.
An engraver is seldom expert in more than one style of work. Each makes a specialty of some branch, portraiture, lettering, scroll-work, etc.
For this reason several engravers are usually employed on each die for a postage stamp. And in this inability of one individual to do all styles of work equally well lies one of the great securities against counterfeiting.
In the course of making a die, proofs are usually taken and these are much prized by collectors.
The die being finished, it is placed in a bath of cyanide of pota.s.sium and heated until the vessel containing it is red hot. This process occupies from fifteen minutes to half an hour for dies but may take as much as an hour for a large plate. The die is then transferred to a bath of oil, to cool and temper it. By this process it is thoroughly hardened.
[Ill.u.s.tration: From ”The Popular Science Monthly,” Vol. XLVI, No. 5.
Copyright, 1895, by D. Appleton & Co.]
In the case of postage stamps, where it is desired to exactly duplicate the design many times on a plate, recourse is had to transfer rolls. A transfer roll is a piece of soft steel, in shape a cross section of a cylinder. The edge is sufficiently wide to receive an impression from the die. We show you here a picture of a transfer press. From each side of the roll projects a small pin or trunion. These pins form an axle for the roll and by them it is held in the carrier of the press. A is the roll in the carrier. The die is placed on the table or bed B. The roll is held against the die with a pressure of many tons, obtained by compound leverage. By means of the wheel, E, and the connecting pinion and rack, the bed, carrying with it the die, is moved back and forth under the roll. This is called ”rocking” and by it the soft steel of the roll is forced into the die and a reverse impression of the design is obtained. The roll is then hardened and, by a reversal of the process, impressions from it are transferred to the steel plate from which the stamps are to be printed. The plate is, of course, soft at first and is hardened after the required number of designs have been transferred to it. This process is so perfect that the most delicate lines of the die are repeated with absolute fidelity on the plate. When many plates of a stamp are likely to be needed, it is customary, in order to avoid risk of wear or damage to the original die, to make duplicate dies, called transfer dies, and from them the necessary rolls to make the plates.
The plates are made with great care. They are touched up by hand and subjected to close scrutiny and the work is often gone over a number of times before the result is p.r.o.nounced satisfactory. Incidentally any guide lines and marks used by the transferrer are removed by burnis.h.i.+ng.
In the older issues of United States stamps, such lines and dots are frequently found on the stamps but the later issues are very free from them.
Plates that have become worn are ”re-entered,” that is to say, the transfer roll is applied to the plate in the original position and the lines thus sharpened and deepened. If, by any mistake in making or re-entering a plate, the roll is incorrectly placed and then changed to the correct spot, a double impression of some of the stronger lines will result. This is called a ”double transfer” and sometimes, though wrongly, a ”s.h.i.+fted die.” These double transfers are quite common in the United States stamps made before 1861 but are scarce in the late issues, either because the work is now more carefully done or because any mistakes have been corrected. Such a correction is effected by turning the plate on its face on a hard substance, hammering on the back until the surface is driven up smooth and then entering the design anew.
A number of very delicate machines are used as aids to the engraver, though much more for bank-notes and large pieces of work than for postage stamps. These are called ruling machines, medallion rulers, cycloidal and geometric lathes. Ruling machines are used to make the backgrounds of portraits, the shadings of letters and similar work.