The report shows that bookbinders and librarians are not, as a general rule, qualified to select leather for bookbinding. In the old days, when the manufacture of leather was comparatively simple, a bookbinder might reasonably be expected to know enough of the processes employed to be able to select his leather. But now so complicated is the manufacture, and so many are the factors to be considered, that an expert should be employed.
"The committee have satisfied themselves that it is possible to test any leather in such a way as to guarantee its suitability for bookbinding. They have not come to any decision as to the desirability of establishing any formal or official standard, though they consider that this is a point which well deserves future consideration."
It is to be hoped that some system of examining and hall-marking leather by some recognised body, may be inst.i.tuted. If librarians will specify that the leather to be employed must be certified to be manufactured according to the recommendations of the Society of Arts Committee, there is no reason why leathers should not be obtained as durable as any ever produced. This would necessitate the examining and testing of batches of leather by experts. At present this can be done more or less privately at various places, such as the Yorkshire College, Leeds, or the Herolds" Inst.i.tute, Bermondsey. In the near future it is to be hoped that some recognised public body, such as one of the great City Companies interested in leather, may be induced to establish a standard, and to test such leathers as are submitted to them, hall-marking those that come up to the standard. This would enable bookbinders and librarians, in ordering leather, to be sure that it had not been injured in its manufacture. The testing, if done by batches, should not add greatly to the cost of the leather.
On the question of the qualities of an ideal bookbinding leather the committee report:--
"It is the opinion of the committee, that the ideal bookbinding leather must have, and retain, great flexibility.... (It) must have a firm grain surface, not easily damaged by friction, and should not be artificially grained.... The committee is of opinion that a pure sumach tannage will answer all these conditions, and that leather can, and will, be now produced that will prove to be as durable as any made in the past."
The committee has so far only dealt with vegetable-tanned leather. I have used, with some success, chrome-tanned calfskin. Chrome leather is difficult to pare, and to work, as it does not become soft when wet, like vegetable-tanned leather. It will stand any reasonable degree of heat, and so might perhaps be useful for top-shelf bindings and for shelf edging. It is extremely strong mechanically, but without further tests I cannot positively recommend it except for trial.
While the strength and probable durability of leather can only be judged by a trained leather chemist, there remains for the binders selection, the kind of leather to use, and its colour.
Most of the leather prepared for bookbinding is too highly finished.
The finishing processes add a good deal to the cost of the leather, and are apt to be injurious to it, and as much of the high finish is lost in covering, it would be better for the bookbinder to get rougher leather and finish it himself when it is on the book.
The leathers in common use for bookbinding are:--
Goatskin, known as morocco.
Calf, known as calf and russia.
Sheepskin, known as roan, basil, skiver, &c.
Pigskin, known as pigskin.
Sealskin, known as seal.
_Morocco_ is probably the best leather for extra binding if properly prepared, but experiment has shown that the expensive Levant moroccos are nearly always ruined in their manufacture. A great many samples of the most expensive Levant morocco were tested, with the result that they were all found to contain free sulphuric acid.
_Calf._--Modern vegetable-tanned calf has become a highly unsatisfactory material, and until some radical changes are made in the methods of manufacturing it, it should not be used for bookbinding.
_Sheepskin._--A properly tanned sheepskin makes a very durable, though rather soft and woolly, leather. Much of the bookbinding leather now made from sheepskin is quite worthless. Bookbinders should refuse to have anything to do with any leather that has been artificially grained, as the process is apt to be highly injurious to the skin.
_Pigskin._--Pigskin is a thoroughly good leather naturally, and very strong, especially the alumed skins; but many of the dyed pigskins are found to be improperly tanned and dyed, and worthless for bookbinding.
_Sealskin_ is highly recommended by one eminent librarian, but I have not yet had any experience of its use for bookbinding.
The leather that I have found most useful is the Niger goatskin, brought from Africa by the Royal Niger Company; it is a very beautiful colour and texture, and has stood all the tests tried, without serious deterioration. The difficulty with this leather is that, being a native production, it is somewhat carelessly prepared, and is much spoiled by flaws and stains on the surface, and many skins are quite worthless. It is to be hoped that before long some of the manufacturers interested will produce skins as good in quality and colour as the best Niger morocco, and with fewer flaws.
Much leather is ruined in order to obtain an absolutely even colour. A slight unevenness of colours is very pleasing, and should rather be encouraged than objected to. That the want of interest in absolutely flat colours has been felt, is shown by the frequency with which the binders get rid of flat, even colours by sprinkling and marbling.
On this point I may quote from the committee: "The sprinkling of leather, either for the production of "sprinkled" calf or "tree" calf, with ferrous sulphate (green vitriol) must be most strongly condemned, as the iron combines with and destroys the tan in the leather, and free sulphuric acid is liberated, which is still more destructive.
Iron acetate or lactate is somewhat less objectionable, but probably the same effects may be obtained with aniline colours without risk to the leather."
CHAPTER XX
Paper--Pastes--Glue
PAPER
Paper may be made by hand or machinery, and either "laid" or "wove."
"Laid" papers are distinguished by wire marks, which are absent in "wove" paper.
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.
Several makers produce coloured handmade papers suitable for end papers. Machine-made papers can be had in endless variety from any number of makers.
The paper known as "j.a.panese Vellum" is a very tough material, and will be found useful for repairing vellum books; the thinnest variety of it is very suitable for mending the backs of broken sections, or for strengthening weak places in paper.
The following delightful account of paper making by hand is quoted from "Evelyn"s Diary, 1641-1706."
"I went to see my Lord of St. Alban"s house at Byflete, an old large building. Thence to the paper mills, where I found them making a coa.r.s.e white paper. They cull the raggs, which are linnen, for white paper, woollen for brown, then they stamp them in troughs to a papp with pestles or hammers like the powder-mills, then put it into a vessell of water, in which they dip a frame closely wyred with a wyre as small as a haire, and as close as a weaver"s reede; on this they take up the papp, the superfluous water draining thro" the wyre; this they dextrously turning, shake out like a pancake on a smooth board between two pieces of flannell, then press it between a greate presse, the flannell sucking out the moisture; then taking it out they ply and dry it on strings, as they dry linnen in the laundry; then dip it in alum-water, lastly polish and make it up in quires. They put some gum in the water in which they macerate the raggs. The mark we find on the sheets is formed in the wyre."
The following are the more usual sizes of printing papers--
Inches.
Foolscap 17 13 Crown 20 15 Post 19 15 Demy 22 17 Medium 24 19 Royal 25 20 Double Pott 25 15 " Foolscap 27 17 Super Royal 27 21 Double Crown 30 20 Imperial 30 22 Double Post 31 19
The corresponding sizes of hand-made papers may differ slightly from the above.
Although the above are the princ.i.p.al sizes named, almost any size can be made to order.
The following is an extract from the report of the Committee of the Society of Arts on the deterioration of paper, published in 1898: "The committee find that the paper-making fibres may be ranged into four cla.s.ses:--
A. Cotton, flax, and hemp.
B. Wood, celluloses (_a_) sulphite process, and (_b_) soda and sulphate process.
C. Esparto and straw celluloses.
D. Mechanical wood pulp.
In regard, therefore, to papers for books and doc.u.ments of permanent value, the selection must be taken in this order, and always with due regard to the fulfilment of the conditions of normal treatment above dealt with as common to all papers."
"The committee have been desirous of bringing their investigations to a practical conclusion in specific terms, viz. by the suggestion of standards of quality. It is evident that in the majority of cases, there is little fault to find with the practical adjustments which rule the trade. They are, therefore, satisfied to limit their specific findings to the following, viz., _Normal standard of quality for book papers required for publications of permanent value._ For such papers they would specify as follows:--
"_Fibres._ Not less than 70 per cent. of fibres of Cla.s.s A.
"_Sizing._ Not more than 2 per cent. rosin, and finished with the normal acidity of pure alum.