The Book: Its History and Development

by Cyril Davenport

The early method of making paper was to allow the pulp to settle at the bottom of a trough like a sieve, with a wire bottom, in which the wires were arranged in a certain way, thick and thin, the trade mark of the maker also being outlined in wire. The faint marks these wires cause in the paper are called watermarks, and although at first they were makers’ marks, they eventually denoted the size of the sheet of paper on which they were shown.

The present method of making paper from rags is to pulp them thoroughly in water, and let the white particles become so thoroughly diffused that the liquid in which they float looks like thin milk.

This thin mixture, however, if left quiet, very quickly resolves itself into a sediment of white fibres with clear water above them. If now the superambient water can be drawn off, and the sediment pressed flat, paper is the result. But it is not so easily done as said. In order to catch the sediment in the most satisfactory way, the milky fluid containing the rag fibres is allowed to flow in a thin stream over a long, shallow trough, which is kept moving onwards and is also so arranged that it has a sideways tremble, backwards and forwards as well. The effect of this is that when the further end of the trough is reached, on its floor there is a thin continuous film of slightly matted fibres, the water from which has flowed away along the sides of the trough. Now another device comes into play; a thin light roller of wire presses lightly on the wet film, and by this pressure the little fibres are pressed upon each other so that they mat, interlace, and cohere together. The paper in this state is of course very delicate, but by reason of a quick drying and carrying off on light rollers it soon acquires the strength necessary to enable it to hold together until it is quite dry. Then it goes through several other stages, the most important of which is pressing. The various processes can obviously be modified easily enough so as to make a thin paper or a thick one. Paper made in this way with a vibratory trough is called “machine made,” and by reason of its fibres laying more or less in a uniform direction the resulting paper is more easily torn in one direction than in the other. If a circular piece be cut out of such pulp and laid on water it will tend to fold up two of its opposite sides.

But ancient paper was made in a trough held by hands and given a lateral movement, then pressed and dried in some simple way. By such a procedure the fibres are thoroughly mixed, and do not lie in one direction more than in another, so that if a circular bit of such paper be laid in water it will turn upwards at the edge evenly all round, and look like a little saucer.

I have mentioned a light wire roller which presses the wet film more or less into shape just before it leaves the long trough to be dried. As long ago as the thirteenth century in Europe the fact that devices could be impressed upon the undried film by thinning it and making it more transparent where touched appears to have been known, and from about that time onwards “watermarks” have fortunately been applied in the same manner, namely, so as to come in the middle of the first leaf of the pair forming a folio. It is also fortunate that the “chains” or wires forming the rollers have always been laid in the same way; it is certainly the obvious one, but obvious ways are not always adopted. The result is that by observing the direction of the strong chain marks and the fine “laid” marks between them much information concerning the folding of the original sheets can be obtained.

In very early papers these rules cannot be safely followed, because early chain marks as well as early watermarks were not produced in the same reliable way. The paper being made in moulds with wire netting at the bottom, the impression came below the paper instead of above it as in the case of the roller, and also the sizes of the sheets were more likely to differ.

Watermarks are the semi-transparent devices which show on certain pages of a printed book. They are to be seen on most papers of the fourteenth to the eighteenth centuries, and there has been a good deal written about them, especially abroad. The devices were outlined in wire and set in the bottom of the trough or on the wire roller I have just described, so that the lines are impressed upon the pulp just when it is in its most sensitive condition. The pressure from the wire device thins the pulp wherever it is touched, and so when dry the device shows lighter than the rest of the paper.

These marks should be called wire marks rather than watermarks, and the French word for them, “Filigranes,” is more correct than ours. The difference in tint between a watermark and the rest of the paper is so distinct that a photographic negative placed under one will render a capital photograph of it, far better than any drawing, but it needs a long exposure.

Watermarks are already of considerable value to Bibliographers, and it is likely that in the near future they will be much more noticed, especially in English books. Many frauds have already been detected by reason of the watermarks, as it is a point that faussaires have so far paid little attention to. The marks are, however, not to be relied on after about 1750, as they do not run reliably in machine made or wove papers.

Armorial devices have been largely used as watermarks. Many of the earlier marks show the arms of towns, especially continental ones, and among others there are the arms of France, Portugal, William and Mary and Queen Anne, shown in full heraldic outlines.