Title

Tasmanian industries [No. 18] Lithography.

Author

Author not identified

Source

Mercury (Hobart)

Details

12 June 1873, p.2, col.7 to p. 3, col.1.

Publication date

12 June 1873

Type

Essay/article

Language

English

Country of context

Australia

Full text

 
TASMANIAN INDUSTRIES
[No. 18]
LITHOGRAPHY
A visit to Mr. Major Hood’s Lithographic and Printing establishment in Elizabeth-street will repay the trouble, for a great deal that is very interesting is to be seen there. The growth of the Tasmanian jam trade has, of course, created a demand for labels, and the manufacture of those generally keeps Mr. Hood busy. If the labels are to be lithographed, the design is either engraved on a copper plate, or drawn with a peculiar kind of ink upon prepared paper. If the former is the method employed, the engraved plate is first of all slightly heated, so that the ink will run into the lines of the design, and is then rubbed over the face of the plate, and wiped again, so that none is left except in the cuts made by the engraver’s tool. An impression of the design is then taken upon prepared paper, in a powerful copper plate press. This paper before it goes under the press has a rough surface, but comes out with a gloss upon it. The next part of the process is to transfer the design from the paper to the stone. For lithography a hard, close-grained stone is used, and it has the property of at once absorbing anything of a greasy nature. The stone, which has an almost polished surface, is heated, to make it more absorbent, and the prepared paper, on which the design has been taken from the plate, is then placed upon it and pressed. The ink in which the design appears on the paper being of a greasy nature, is at once absorbed by the stone, and the transfer is complete. We will suppose that several hundred small labels are to be printed in only one colour. The design would be transferred from the copper plate to the stone in the manner we have described, and a large stone being selected for the purpose, half-a-dozen copies of the design would be transferred to it. This having been done, the stone has to be allowed to cool, after which it is rubbed over with an acid solution. Everything is now ready for printing, and the rest of the process appears to be exceedingly simple, while, in fact it is not, but requires a deal of skill and care. If the ink roller, which is nearly similar to those used in all printing offices, were to be passed over the stone, the ink would be absorbed wherever it touched; to prevent this the operator before applying the ink rubs the stone over with a damp cloth. The lines of the design are greasy and repel the water, which remains on the clear parts of the stone, allowing the ink to pass over it without adhering anywhere except on the lines. The paper upon which the design has to be printed is then placed on the stone and pressed. The ink has to be applied after each impression in the same manner as in ordinary printing, and the operator, who perhaps has a large stone before him, has to take care that the ink is evenly distributed, in order that one part of the design may not come out darker than the other. In label printing two, three and sometimes more different colours are generally used in the same design, and when this is the case, there is a stone for each colour. As an illustration, we will suppose that a label has to be printed with a red star in the centre, the star surrounded by a blue circle, and the whole design having a black border. The red star will be transferred to one stone, the blue circle to another, and the black border to a third, and each has to be printed separately, care being taken to ensure perfect accuracy. As we mentioned before, the copper plate is not always used in lithography. A letter may be written on prepared paper and transferred to the stone in the manner we have described; and at Mr. Hood’s we were shown a map of Launceston that was drawn with prepared ink and paper, and then transferred to the stone. When the design is no longer required, the stones have to be cleaned and this is pretty hard work. The surface has to be rubbed down with pumice stone, and finished off with snake stone, great care being taken to keep the surface perfectly level. Besides labels, Mr. Hood prints maps, visiting and other kinds of cards, billboards, plans, &c. In the first room we visited, was the copper plate press and the lithographic press. Here Mr. Brandt, the gentleman in charge of this part of the establishment was hard at work, and by him we were shown the different processes we have described. In the next room two lads were at work printing in different colours. Upstairs some electro-type printing was being done. The electro-types are simply metal blocks, which have been cast to the form of the design. In electro-type colour printing there is a block for each colour, and one is printed after the other, in the same manner we have described in connection with the lithography. In the electrotype room there is a large Albion press, and a small lithographic press for transferring a design from one stone to another. For instance, if a design is on a small stone, and it is intended to print large number of copies, this may be done in less time by transferring it five or six times to a larger stone, from which it can then be printed. In another apartment is a large patent ruling machine, for ruling paper and books. This is done by passing the paper under a row of pens arranged as far apart as it is desired to have the lines. These are not at all like ordinary writing pens. Each is in reality a little fine pointed spout through which the ink drains in small quantities from a piece of flannel that has been thoroughly saturated with it. In the same room there is also an embossing press. The labels are varnished before they leave the premises, and some of them are gummed on the under side. When this is done they are cut and tied up in bundles of five hundred each, ready for delivery. In the yard there is a stamp of Mr. Hood’s own invention for cutting out circular labels for the tops and bottoms of the jam tins. It looks something like a small pile driver, and works on the same principle. The art of lithographic printing is a very interesting one, and a glance over Mr. Hood’s specimen book shown the perfection to which it is now carried.

[Mercury (Hobart), 12 June 1873, p.2, col.7 to p. 3, col.1.
]