_c._ Weight per yard.

_d._ Tensile strength.

_e._ Amount of stretch.

_f._ Amount of friction developed by rubbing two pieces of cloth together.

This test was made because the friction developed in taking a book from between two others is an important matter when a shelf is full of books.

If the friction is great the wear on the back of the book is correspondingly excessive.

_g._ Endurance when folded back and forth in the same place.

_h._ Endurance under extraordinary conditions of rubbing.

Some of these qualities, such as tensile strength, amount of stretch, etc., were comparatively unimportant, but the tests for all were severe and contributed much to our knowledge of the qualities which should enter into the composition of durable book cloths.

After a very careful consideration of the results of the tests and a thorough examination of the samples submitted, a committee of librarians and government officials unanimously chose three samples as the best of all those submitted by the manufacturers. Of these three samples the cloth numbered 666 was considered the most satisfactory.

Although these three samples were excellent, they all had one defect--the color was pressed in by machinery, not dyed in the piece.

After various experiments had been made by the manufacturers this defect was remedied. The Government Printing Office then advertised for bids on cloths which would meet the Specifications drawn up by the Bureau of Standards (See Appendix A). Since that time all the Government doc.u.ments which continue the old sheep-bound set have been sent to depository libraries bound in cloth made according to these specifications.

This cloth is known sometimes as Government Specification Cloth, but is manufactured under the specific name of "Library buckram" by the Holliston Mills, "Art buckram" by the Interlaken Mills, and "Legal buckram" by the Joseph Bancroft & Sons Company. The first two are made in pieces about 40 yards long and 38 inches wide, the Bancroft cloth in pieces 43 yards long and 43 inches wide. It must be admitted that this cloth is not quite so attractive in appearance as some of the old cloths which are not so durable. Some binders claim that it is hard to use. On the whole, however, it supplies a long felt want and is the strongest cloth made that is at all attractive in appearance.

DUCK

Duck or canvas, a rough, heavy cloth much the same in quality as sail cloth, is the strongest cloth used in binding, but has some very decided drawbacks which militate against its use, except when the question of strength overshadows all others. It always makes an unattractive-looking volume--some of the more fastidious librarians rebel against its use; and it readily absorbs dirt and moisture, making it disagreeable to handle if the book has been much used. Duck having a double twisted thread in the weft is much more compact and absorbs dirt and moisture much less rapidly than other kinds. It should be used on the backs (never for full binding) of newspapers and such periodicals as are too heavy to put in library or legal buckram.

IMPERIAL MOROCCO CLOTH

Imperial morocco cloth, manufactured by the Winterbottom Book Cloth Company in England, is made of linen thread and finished with a grain to resemble leather. The kind most used in the United States resembles a straight-grained morocco. It is an excellent cloth in appearance, as well as in durability, but its cost is 50% greater than that of the Government Specification Cloth. It may be used on semi-popular books which will not receive a great amount of use, but which should be as attractive in appearance as possible.

WATER-PROOF CLOTHS

There are several cloths which are waterproof and therefore easily cleaned when the covers become soiled. The best of these are durabline, used exclusively by Cedric Chivers; rexine and pluviusin, used almost exclusively in England; keratol, made in Newark, New Jersey; and fabrikoid, made by the du Pont Powder Company, Wilmington, Delaware. All of these cloths are said to be acid, alkali and germ proof, do not absorb grease and can be washed with soap and water. They are strong, durable cloths, but they have at first a disagreeable odor, are hard to work and hard to letter in gold. In the application of paste to most waterproof cloths, either in the process of binding or in attaching labels to the back, it is first necessary to break down the surface of the cloth or the paste will not hold. This disadvantage no longer exists in the case of fabrikoid. Keratol and fabrikoid are made to imitate leather and are frankly sold as such. Probably the use of these cloths in libraries will always be comparatively small. Because they can be easily cleaned they may be used on the sides of juvenile books, and in rare cases for full binding.

GLUE

No very definite rules can be laid down as to what kind of glue should be used. The matter must be left largely in the hands of the binder, who must see that it is strong, yet flexible; not too poor in quality nor yet the most expensive kind which is generally used on furniture. This is too brittle for bookbinding use.

The best glue for bookbinding is made from skins and shows a dark wine color in the cake. Light colored glues are made chiefly from bones and are not usually so good. To prepare glue for use, soak small pieces in water over night and in the morning melt in the glue pot. It should never be boiled. A careful binder will see that utensils are kept clean and that glue is used in the proper thickness.

Flexible glue, which does not become too hard either before or after use, is made by mixing glycerine with good glue. It has no special advantages for use by binders, but can be used in the library itself for some of the repairs which a.s.sistants may have to make.

PASTE

(For paste used in mending, see p. 167).

The best paste is that made in the ordinary way with flour and water.

The paste should be fresh, for if it is not a certain fermentation takes place which is injurious to the book, especially to leather.

BOARDS

Not the least important part of the make-up of a finished book are the boards forming the sides. There are practically four grades of boards which are known as strawboards; binders, cloth or millboards; semi-tar, and tar boards. The cheapest grade is the strawboard, for which there is no place in library work.

Mill or cloth boards, used for practically all library work, are generally made from waste papers of all kinds, though some may have an admixture of rags. Clay is also mixed with the waste paper pulp and the whole subjected to heavy pressure in the final stages of manufacture.

They are made in two sizes, 20 30 and 23 29 inches, and are put up in 50-pound bundles, the number of sheets in the bundle indicating the thickness of the board. The thickest is a No. 12 which has 12 sheets in a 50-pound bundle. They may have as many as 70 sheets in a bundle, which makes a very thin board. A 20 or 25 board should be used for fiction and juvenile books and a 16 or 18 for heavier books such as magazines.

Prices of good cloth boards run from $40 to $50 a ton.

Semi-tar boards, made from better grade stock than mill board, should have in their composition a certain amount of rags and hemp or naval cordage. They come in the same sizes and weights, costing about $70 a ton.

Tar boards are the best boards obtainable. Made of naval cordage, they are very tough and hard to work. Many of them are allowed to season, in much the same way as lumber seasons, in order to prevent warping. They are much too expensive for library use, sometimes costing as much as $110 a ton.

The matter of boards is not one about which the librarian need exercise great watchfulness. Binders generally use a very good quality, though they sometimes use too thin a board on a heavy book, such as a newspaper or large folio. In such cases a board of suitable thickness can be made by pasting or gluing two or more together.

THREAD

At one time there was no question but that the best thread to be used in binding was linen. In the light of present knowledge it may be doubted if this is true under all circ.u.mstances. All commercially bound books, without exception, are sewed with cotton thread. Even such large books as the Century Dictionary, Webster's Dictionary and the United States Catalog of 1912 are sewed with cotton thread. Since it was unquestionably the aim of the publishers of all these books to issue them in the strongest possible bindings, it is reasonable to suppose that linen would have been used if it were really the best for the purpose. The main reason linen thread has been advised for so long is because its tensile strength is much greater than that of cotton. On the other hand, it is just as true that what we may call the fraying resistance of a cotton thread is greater than that of linen. Take two threads of the same size, one cotton and the other linen, make a loop of each thread with one inside the other, saw back and forth, and the cotton will always cut the linen thread. Furthermore, linen thread deteriorates in quality unless very carefully stored. The publishers soon discovered these facts, and since tensile strength is not an important attribute in a thread that is being used in a book sewing-machine, they use a cotton thread with thoroughly satisfactory results.

In the case of library binding, however, the books are always sewed by hand and the sewer, as she draws the thread tight, is obliged to use some strength; for this reason tensile strength is an important attribute. Hayes' Irish linen thread is generally specified. The Barbour thread is referred to by Mr. Dana and by others, but the writer is not familiar with its use.

Other materials used in binding are gold leaf, paper for end papers, tape, headbands, cord and various concoctions used in finishing the books. Gold leaf should be 18 to 22 karat, and neither aluminum nor silver leaf should be used. Paper for end papers will vary somewhat with the size of the book, but should never be lighter in weight than a 60-pound manila. Large libraries may find it desirable to have an end paper specially made for their own use. Tapes should be linen and not over three-eighths of an inch wide. Cord for use in sewing in the regular way (not overcasting) is a soft twine which can be obtained from all dealers in bookbinding supplies. For all books less than twelve inches in height use four-ply cord; for larger books, five-ply.

CHAPTER V

SPECIFICATIONS

After the librarian has definitely decided upon the binder whom he wishes to employ he must, especially in dealing with binders who are not accustomed to library work, draw up specifications as to ways in which he wishes different cla.s.ses of books bound. If he has employed a binder who thoroughly understands library binding, he may make use of the binder's knowledge in drawing up the specifications. Under certain circ.u.mstances it may be wise to enter into a contract with the binder, but ordinarily in the United States such a course will not be necessary.

After the specifications have been prepared and a schedule of prices agreed upon, the librarian always has the right to refuse to pay for books not bound according to specifications. Therefore, a definite legal contract is not necessary. The librarian, except in the case of a few libraries which according to law must give their work to state officials, is always at liberty to take his custom from one binder and give it to another. Thus sufficient pressure is brought to bear on the binder.

Although the present chapter gives definite specifications for the binding of various cla.s.ses of books, it is always wise to show a certain lat.i.tude in the use of specifications. Local conditions, the papers used in bookmaking which seem to become poorer and poorer with each succeeding year, and the kind of a library which is to use the specifications--all these must be taken into consideration when specifications are drawn up. Moreover, the best specifications will accomplish little if they are not followed by the binder in a workmanlike manner, while good workmanship will sometimes make up for omission of important details in the specifications.

In the main, it will be found that the following specifications may be used as a guide, except possibly in the case of some reference and college libraries which do not issue books for home use. It has seemed best to place first general specifications which apply to all books, followed by additional specifications for each kind of books treated.

The way in which these specifications are carried out is described in the chapter on Processes.

GENERAL SPECIFICATIONS

1. The binder is responsible for all books consigned to his care and must replace or pay for all books lost or injured. When one considers the large number of volumes pa.s.sing through a bindery, coming from many different libraries, the number of books for which the binder is unable to account is surprisingly small.

2. The librarian is the judge of whether the book is bound according to the specifications. Since he has submitted the specifications and the binder has agreed to them he should be the sole judge of the result.