=Leather: General Notes=
The names given to different kinds of leather come sometimes from the
character of its surface, that is, from the "grain," or roughness
or corrugation it has; sometimes from the animal it once covered;
sometimes from the method of tanning; sometimes from the fact that it
is part of a skin which has been split; sometimes from the place or
country where it is made or where the animal it once covered lived, and
sometimes from a combination of two or more of these.
The subject of the leathers used in bookbinding is a very difficult
one. Tanners, dealers and binders, dictionaries, encyclopædias and
books on tanning disagree with one another as to the proper terms to
use in speaking of different kinds of leather. Imitations are many, and
very successful. In the list below I have tried to follow the usage of
binders; but I am sure no expert would accept it throughout as correct.
With this variety in definition goes a corresponding variety in
character in leather of the same name. Different skins tanned in the
same way, apparently, and called by the same name by dealers and
binders, will wear, some well, some not so well. The only quite
definite assertion which can be made is, that of modern leathers, few
save the best morocco and pigskin will keep their strength for any
length of time in an American library, and morocco and pigskin usually
for not much over 20 years.
As the remarks which follow indicate, English leather makers have
recently procured leathers guaranteed to be dressed on the lines
recommended by the Society of Arts Report. See also the revised report,
and the little volume, with samples, called Leather for Libraries by
Hulme, Parker and others.
Leathers made from the skins of animals of the same kind, the goat
for example, though made by the same process, vary somewhat with the
animals' sex, age when killed, the food on which they lived, the
climate in which they matured, and their manner of life, and, if
females, with the fact that they have or have not had young. Also, the
leather made from the skin of one part of the body differs materially
from that made from the skin of another part.
Moreover, some dyes seem to hasten decay, some to retard it. Red seems
least hurtful, black the most so; though this difference is probably
due more to chemicals used in the preparation of the skin for the dye
than to the dye itself. Brown generally stands well; most other colors,
except red as stated, do not.
With all these, and other, factors to be taken into consideration it
is evident that full knowledge of leather is not given to anyone. In a
general way it may be said that good leather cannot be told by name,
or looks, or feel; but only by trial. Dealers, even, cannot tell the
good from the best.
The sum of all advice is, having found, by your own or others' tests,
that a certain leather is good, use it as long as you can get it. The
British museum sets a good example in this. It has in recent years
bound many thousands of volumes in morocco made by Meredith-Jones &
Sons, Wrexham, Wales, which experience thus far shows to be very good.
We have tried it and in the brief trial we have given it, found it
excellent.
Dr. J. Gordon Parker, Herold's Institute, Drummond Road, Bermondsey,
England, has made an arrangement with the council of the Library
Association of England by which he has become their official examiner
of leather and he will test samples for acids, nature of tannage, etc.,
at reasonable rates.
John Muir & Son, tanners and curriers, Beith, Scotland, offices: 3
Arundel St., Strand, London, W. C., England, prepare pigskin for
bookbinding; so do Edw. & Jas. Richardson, Elswick Leather Works,
Newcastle-on-Tyne, England.
J. Meredith-Jones & Sons, Ltd., Cambrian Leather Works, Wrexham, Wales,
make bookbinders' leathers guaranteed to be dressed on the lines
recommended by the Society of Arts Report, and free from mineral acids.
Specialty: Welsh sheep.
Much has been written on the wearing and lasting qualities of leather.
The best discussion of the subject is the Report of the committee
on leather for bookbinding, made to the Society of Arts, England,
and published in its Journal, July 5, 1901. I allude to this report
frequently, and for convenience speak of it as "Report '01." The
committee who made this report found that the leather made today does
not last as long as that made 75 years ago. They found that the heat
and fumes of gas help to hasten the decay of the leather on books.
These factors are more effective in American superheated libraries
than in English ones. If books bound in leather are much handled they
last longer than if they stand undisturbed on the shelves, because the
oil from the hand helps to keep leather soft, pliable, and alive. The
committee concluded that no leather, with the sole exception of Niger
goat, made by the natives on the river Niger in Africa, and imported
just as it leaves their hands, can be fully recommended as free from
elements which lead to its early decay. Since this report was published
imitations of this leather have been put on the market, and it can no
longer be relied upon. We have found it beautiful in color and texture,
easy to work and wearing admirably on large and much-used books. But
it does not keep clean as well as a good morocco of coarse grain. It
is very expensive, and first-class morocco is probably better where
strong, enduring leather is advisable which is only on books which are
to be much used.
The most important points made in the report of the Society of Arts
committee on leather for bookbinding, referred to above, are the
following:
Books bound during the last 80 or 100 years show far greater evidence
of deterioration than those of an earlier date. Many recent bindings
show evidence of decay after so short a period as ten or even five,
years. Modern leather is certainly far less durable than old leather.
The most prevalent decay is a red decay, and this may be differentiated
into old and new, the old red decay being noticeable up to about 1830,
and the new decay since that date.
Another form of deterioration, more noticeable in the newer books,
renders the grain of the leather liable to peel off when exposed to the
slightest friction. This is the most common form of decay noted in the
most recent leathers.
Decay is caused by both mechanical and chemical influences. Of the
latter some are due to mistakes of the leather manufacturer and the
bookbinder, others to the want of ventilation, and improper heating and
lighting of libraries. In some cases inferior leathers are finished (by
methods in themselves injurious) to imitate a better class of leathers,
and of course where these are used durability cannot be expected. But
in the main the injury for which the manufacturer and bookbinder are
responsible must be attributed rather to ignorance of the effect of the
means employed to give the leather the outward qualities required for
binding, than to the intentional production of an inferior article.
Embossing leather under heavy pressure to imitate a grain has a very
injurious effect.
The shaving of thick skins greatly reduces the strength of the leather
by cutting away the tough fibers of the inner part of the skin.
The use of mineral acids in brightening the color of leather, and in
the process of dyeing, has a serious effect in lessening its resistance
to decay.
Quite modern leather dyed black seems, in nearly all cases, to have
perished, although old black morocco (sixteenth, seventeenth and
eighteenth centuries) in good condition is not uncommon.
In a very large proportion of cases the decay of modern sumac-tanned
leather has been due to the sulphuric acid used in the dye bath, and
retained in the skin.
Tobacco smoke has a darkening and deleterious effect on leather
bindings.
Light, and especially direct sunlight and hot air, possess deleterious
influences which had scarcely been suspected.
Gas fumes are the most injurious of all the influences to which books
are subjected, no doubt because of sulphuric and sulphurous acid they
contain. They are especially injurious to books on the upper shelves of
a high room.
The importance of moderate temperature and thorough ventilation of
libraries cannot be too much insisted on. With proper conditions of
ventilation, temperature, and dryness, books may be preserved without
deterioration, for very long periods, on open shelves.
On the other hand, as a general rule, tightly fitting glass cases
conduce to their preservation.
Leather bindings that have been coated with glair or varnish seem to
keep better than those without.
The bookbinder shares, in no small measure, with the leather
manufacturer and librarian, the blame for the premature decay of
leather bindings.
Books are sewn on too few and too thin cords, and are not firmly laced
into the boards. This renders the attachment of the boards to the book
almost entirely dependent on the strength of the leather.
The use of hollow backs usually throws too much strain on the joints in
opening and shutting the book.
If the headbands are not strong the leather of the back is apt to
become torn.
The leather is often made very wet and stretched a great deal in
covering, with the result that, on drying, it is further strained,
almost to breaking point, by contraction, leaving a very small margin
of strength to meet the accidents of use.
The use of oxalic acid for washing backs of books, or of leather for
bookbinding, is fatal to durability. Vinegar, even in its pure state,
is injurious.
Paste should be used in a fresh condition, otherwise it is liable to
undergo an acid fermentation, and to favor the growth of injurious
moulds and bacteria.
In all contracts and specifications for bookbinding, the use of East
India-tanned goat and sheep, whether retanned or not, should be
absolutely forbidden.
It appears to be the general opinion that leather, and especially
Russia leather, lasts better on books that are in constant use. This is
attributed to the slight amount of grease absorbed by the leather from
the hand, and it is suggested that possibly a suitable dressing may be
discovered which would have a similar effect to that produced by this
grease.
While the leather now used for binding books is less durable than that
employed 50 years and more ago, there ought to be no difficulty in
providing leather at the present time as good as any previously made.
It is possible to test any leather in such a way as to guarantee its
suitability for bookbinding.
A reissue of the report summarized above was published, in cloth, in
1905. It is entered in the list of books at the end of this volume.
In this reissue the arrangement of the original report is somewhat
modified; a paper on leather dyes and dyeing has been added; the report
of the scientific sub-committee has been practically rewritten; many
illustrations have been added, some of them colored; 12 samples of
leather prepared in accordance with the committee's conclusions are
inserted; and the volume is handsomely printed, and bound in cloth.
The reissue, however, does not make necessary any change in the above
summary.