A sheet of hand-made paper has all round it a rough uneven edge called the "deckle," that is a necessary result of its method of manufacture. The early printers looked upon this ragged edge as a defect, and almost invariably trimmed most of it off before putting books into permanent bindings. Book-lovers quite rightly like to find traces of the "deckle" edge, as evidence that a volume has not been unduly reduced by the binder. But it has now become the fashion to admire the "deckle" for its own sake, and to leave books on hand-made paper absolutely untrimmed, with ragged edges that collect the dirt, are unsightly, and troublesome to turn over. So far has this craze gone, that machine-made paper is often put through an extra process to give it a sham deckle edge.
Roughly speaking, paper varies in quality according to the proportion of fibrous material, such as rag, used in the manufacture. To make paper satisfactorily by hand, a large proportion of such fibrous material is necessary, so that the fact that the paper is hand-made is to some extent a guarantee of its quality. There are various qualities of hand-made paper, made from different materials, chiefly linen and cotton rags. The best paper is made from pure linen rag, and poorer hand-made paper from cotton rag, while other qualities contain a mixture of the two or other substances.
It is possible to make a thoroughly good paper by machinery if good materials are used. Some excellent papers are made by machinery; but the enormous demand for paper, together with the fact that now almost any fibrous material can be made into paper, has resulted in the production, in recent years, of, perhaps, the worst papers that have ever been seen.
This would not matter if the use of the poor papers were restricted to newspapers and other ephemeral literature, but when, as is often the case, paper of very poor quality is used for books of permanent literary interest, the matter is serious enough.
Among the worst papers made are the heavily loaded "Art" papers that are prepared for the printing of half-toned process blocks. It is to be hoped that before long the paper makers will produce a paper that, while suitable for printing half-toned blocks, will be more serviceable, and will have a less unpleasant surface.