MATERIALS
In a recent pamphlet issued by the Government Printing Office,
containing a list of materials and articles used in the printing and
binding of public documents, the number of items for binding alone
reaches the surprising total of 171. Many of these are materials used in
marbling, others indicate slight variations of color and weight in
standard leathers and cloths. But exclusive of all these the number of
materials called for is over forty.
It is not the writer's purpose to discuss all of these forty or more
materials, but it seems necessary to mention that many materials other
than those used in covering books (always some kind of cloth or leather)
are used in binding. Furthermore, the strength of the book after it is
bound will depend almost as much upon the materials used in its inner
construction as upon those used in covering it. The inner materials, if
not wisely selected as to quality or in reference to the kind of service
which the book is to receive, may cause an otherwise excellently bound
book to give poor service.
In general, however, a reference to binding materials means those which
are used in covering books. It is the cover which renders a book
attractive or unattractive, and which contributes more than any other
one item, except possibly sewing, to the long life of the book. We
should therefore know the initial cost of different covering materials
and the length of service which each material will give under different
conditions. When they are not imitations we should be able to recognize
the best-known materials, either on or off the books. An unscrupulous
binder can easily take advantage of ignorance of these matters.
So far as the librarian is concerned only two classes of materials need
be considered for the covers of books--leathers and book cloths. This
does not indicate a restriction of choice, for when we consider that
leather comes from a large number of animals, that there are a great
many different kinds of cloth, that cloths and leathers can be obtained
in a great variety of colors, there seems to be an embarrassment of
riches. As a matter of fact most librarians confine themselves to four
kinds of leather and four or five kinds of cloth, each in three or four
different shades.
LEATHER
The most expensive materials used in covering books and those which
vary most in quality are leathers, the skins of animals which have been
tanned and made flexible. The best bookbinding leathers are those which
are flexible both in the skin and on books, and the surface of which is
not easily damaged by friction. Owing to the many kinds of leathers and
their variation in quality, it is difficult to learn to know them well.
The skins of all sorts of animals have been used for covering books.
Certain ones, not suitable for library binding, are still used for the
purpose in various parts of the country, so that librarians need to
become expert in their knowledge of which leathers may be employed and
which ought to be rejected.
Variations in the same kinds of leathers are caused by:
(_a_) _Age._ Skins of animals which have not reached full growth should
not be used for binding library books. Since they are immature, the
fibres have not become tough, and they have not reached their maximum
thickness. If the skins which the binder is using are exceptionally
small, it is probable that the animals from which they were obtained
were too young. On the other hand, the skins of very old animals should
not be used, since the fibres of the skins have lost something of their
flexibility and strength. They cannot be readily detected, but they are
sure to give poor service. As an illustration of the effect which age
has upon leather it will be sufficient to note the well-known fact that
calf skin is useless for library purposes, while cowhide within certain
well-defined limits is exceedingly useful.
(_b_) _The sex of the animal._ It has been proved beyond question that
the skin from the female of some animals, notably goats, does not wear
as well as that from the male.
(_c_) _Country from which they come._ It is an interesting fact that the
skin of a sheep which comes from Persia is not the same kind of a skin
as that of a sheep which is raised in the United States. In general, it
may be said that skins from animals inhabiting warm countries are more
likely to be serviceable than those from the same kind of animals
inhabiting cold countries. In the cold countries more of the strength
goes into the fur or hair which protects it, while in warm countries a
greater amount of strength goes into the skin itself.
In addition to variations due to these causes there is likely to be a
certain amount of variation in different parts of the same skin. That
part of the skin which comes from the back of the animal is tougher than
that which comes from the abdomen. The difference is very noticeable in
the skins of some animals, less so in others.
_Decay of Leather._ Of late years there has been much dissatisfaction
expressed over the decay of modern leathers. In many cases leathers 100
years old or more are in a fair state of preservation, while many
leathers--perhaps we should say most leathers--30, 20 or even 10 years
old, show signs of decay, and some have rotted away almost entirely. In
no way is the decay of modern leathers shown more conclusively than in
a long file of the sheep-bound set of the United States Public
Documents. The earlier volumes, covering the 15th Congress up to the
36th, will in general be found to be in a good state of preservation.
About the year 1860, however, marked deterioration appears. In some
cases it seems as if the backs had entirely disintegrated. While a
sheep-bound set is the best example of the decay of modern leathers,
many libraries have been greatly annoyed by the decay of other leathers
which are supposed to be much stronger than sheepskin.
So great was the dissatisfaction with modern leathers that in the year
1900 the Society of Arts in London appointed a committee to investigate
modern leathers and to ascertain the best methods for preparing leathers
for binding. The report of this committee was published in 1905, and a
general knowledge of its contents is necessary for those who wish to
know why leathers decay and how they may be preserved. Another valuable
work which should be carefully studied is entitled "Leathers for
libraries," published by the Sound Leather Committee of the Library
Association in England. In a chapter of this book J. Gordon Parker, Ph.
D., Director of the London Leather Industries Research Laboratories,
tells us that the chief causes of decay are as follows:
1. The introduction of tanning materials other than oak and sumac,
stronger in tannin, and more rapid in their action. Many of these
tanning materials are unstable, and the leather produced
disintegrates on exposure to light and air.
Tanning is the process of changing hides, which are animal matter
subject to decay, into material which is strong and flexible and which
is not subject to decay. There are two groups of tanning materials. The
one called the pyrogallol group, which includes sumac, gall nuts and oak
bark, is commended by the Committee of the Society of Arts. The other is
called the catechol group and is strongly condemned. Among the materials
belonging to the catechol group are hemlock bark and larch, used chiefly
in this country, and turwar bark used largely in tanning East Indian
goat and sheep skins.
The United States Government Printing Office proposals call for leathers
tanned with a pyrogallol tannin, since it has been proved that such
leathers prove most resistant to the evil effects of light, heat and
gas. If a skin has been tanned with sumac, or sumac in combination with
oak bark, it has received the best possible preparation for its life as
a bookbinding leather.
It is not possible, neither is it necessary, to have all leathers tanned
with sumac. Those leathers which are intended to remain on the shelves
for many decades, should be in this tannage. Those which will be
discarded in a few years may be tanned in a less expensive manner. Even
some of the quick, modern materials, which accomplish in a few hours
what once would have taken weeks, are not too poor for leathers which
are not to be kept indefinitely.
Even the expert cannot detect skins which have not been tanned and dyed
properly, but leathers which last a short time may be suspected either
of being improperly tanned or of having some kind of injurious acid in
their composition.
2. The use of dried and cured skins of variable soundness imported
from abroad. Goat, calf and sheep skins are imported into this
country (England) from all over the world; some are simply dried in
the sun, some salted, whilst others are cured with various
ingredients.
3. The use of infusions of acids and other bleaching agents to
produce bright and even shades of colour.
Skins tanned with sumac are light-colored and can be dyed any desired
color. Most other tanning materials, however, make darker-colored skins,
which can be dyed only with dark colors. It has been found possible to
scour and bleach skins with sulphuric acid and to re-tan with sumac.
4. The use of sulphuric or other mineral acids for the purpose of
developing the depth of colour during the process of dyeing.
Sulphuric acid is the cause of decay of over 90% of modern bookbinding
leathers. Having once been used, it cannot be wholly removed without the
use of other chemicals.
5. The shaving and splitting of skins for producing an even
substance.
In splitting and shaving, the long, strongest fibres of the skin are
torn or cut off, and the part which remains for binding purposes is the
weakest part of the skin.
6. Printing and embossing grains upon leather, together with other
methods of finishing now in common use.
There are various ways of bringing out the natural grain of leathers
which are perfectly legitimate and which do no harm. The danger in
graining comes when the grain is embossed by means of a plate, which is
heated and pressed on the skin. No good leather should ever be embossed.
7. The stripping, scouring, souring and re-tanning of East India
leathers (Persians).
Some imported skins are only partially tanned, and it is necessary to
wash out the tannin with some kind of alkali, which also takes out much
of the natural grease of the skin. They are then treated with sulphuric
acid and re-tanned. They are always poor and are seldom sold as
re-tanned skins.
8. The removal of the natural grease or nourishment of the skin.
The foregoing eight causes of decay are beyond our direct control. The
leathers are manufactured and put on the market, and the binder has to
use such as he is able to obtain. No matter how much the librarian may
insist upon leathers free-from-acid, he is helpless if the binder cannot
obtain them. All that he can do is to insist that leathers without acid
must be used, if obtainable.
Although these causes of decay are beyond the librarian's control, there
are several causes of decay quite within his power to avoid. They are
the following, due to improper methods used in binding, or to physical
conditions after the book is on the shelf:
1. Direct sunlight.
2. Gas fumes. This evil is hard to guard against if there are gas pipes
in the building. There is sure to be more or less leakage, and even a
small amount of gas in the air has a bad effect upon leather.
3. Tobacco smoke. This is not likely to be very detrimental in
libraries, since the rules generally forbid smoking.
4. Excessive dampness, which encourages mildew.
5. Extreme dry heat. A temperature much in excess of 70 deg. Fahrenheit is
likely to dry up the oil which gives flexibility to leather.
6. Undue wetting or stretching the leather in covering. Some binders
soak the leathers and stretch them in placing them on the books. When
the leathers dry they shrink, the fibres are strained and the life of
the leather shortened.
7. Use of poor paste in binding. This frequently sets up a fermentation
that is very harmful to leathers.
8. Dust, especially in conjunction with dampness, is very injurious to
leather.
Doubtless there are other things which have a deleterious effect upon
leathers in libraries; but if a library is well ventilated, if
leather-covered books are not kept in cellars or basements that are very
damp, or where direct sunlight can fall upon them, and if the binder
uses good paste and proper care in covering the books, we may reasonably
place the responsibility of undue decay of leathers upon the
manufacturers.
The various reports quoted so far have dealt with qualities of leathers
due to tanning, manufacture, method of binding and time in use. Natural
or mechanical qualities of leathers have not been touched upon. Those
who are interested in this phase of the question should read the report
of Mr. Cedric Chivers on "The relative value of leathers and other
binding materials," made at the meeting of the American Library
Association at Pasadena in 1911. Mr. Chivers employed Mr. Alfred Seymour
Jones, in England, to make tests which would show the tearing and
breaking strain of various leathers. These natural qualities of leathers
are obviously important, but too much stress must not be laid upon them.
It is possible that a leather naturally strong and tough when new would
rapidly deteriorate with age. The records as presented in Mr. Chivers'
report must be taken in conjunction with facts determined by the
investigation of the Society of Arts. In the main, however, it will be
found that leathers which best stood the tests of the Society of Arts
also showed the greatest resistance to the tearing and breaking strains
made by Mr. Chivers.
_Preservation of Leather._ Various attempts have been made both by
librarians and others to discover some substance which would preserve
leather effectually after the book is bound. Some of these attempts have
been temporarily successful, but time alone will tell whether leathers
are permanently preserved by the treatments used, or whether
applications of the preservative must be frequently made. Owing to the
fact that in law libraries practically all the books published previous
to 1900 were bound in sheepskin, the lasting qualities of leathers is a
question that affects law libraries more than any other. Dr. Wire, of
the Worcester (Mass.) County Law Library, who has made a careful study
of the problem, advises the use of vaseline or some other similar
by-product of petroleum well rubbed into the leather with the bare hand
and allowed to dry in the air until the leather has absorbed it. Better
results were obtained by allowing the volumes to dry in the summer by
natural heat instead of artificial heat in the winter. For some books
Dr. Wire makes use of a bookbinder's varnish after the softening product
has thoroughly penetrated the leather. A full description of the
processes may be obtained from Dr. Wire's pamphlet, "Leather
preservation," published in 1911.
Some of the disadvantages of Dr. Wire's method are:
1. The necessity of rubbing in the preservative from three to five
times, according to the condition of the leather at the time of first
treatment.
2. The care necessary to prevent the material used from smearing tables,
trucks, floor, shelves and clothing at time of application; also when
books are back on the shelves the care required to keep from rubbing
against them and the necessity of wiping them off when they are handed
to readers.
3. The tendency of books to swell at the back when first treated in this
way, demanding extra care lest, in an effort to pull out one book, a
whole shelf-full fall to the floor.
4. The repetition of the process after ten years.
It is possible that these drawbacks will be sufficient to dissuade all
except the most stout-hearted from using this method of preserving
leather. Rebinding in cloth seems to be much more simple and, on the
whole, not much more expensive.
The question of a preservative is discussed in the Report of the Society
of Arts, from which the following quotation is taken:
Enquiries have frequently been made as to the use of
preservative pastes upon old bindings. It has been mentioned
that the seasonings of white of egg or blood albumen usually
employed in finishing leather have some preservative effect,
and no harm can arise from the application of very thin
coatings of white of egg. The use of ammonia to thin or
preserve the solution must be avoided, but the whites, after
thorough beating, may be rendered antiseptic by the addition
of a small quantity of camphor, thymol, or some essential oil.
Vaseline has been employed as a dressing, and, if otherwise
suitable, will no doubt have a preservative effect upon the
leather. A very moderate use of the wax, soap, and turpentine
preparations made as shoe pastes, is also likely to be
beneficial, and no doubt a special preparation might be made
on these lines which would be still more suitable. Paraffin wax
dissolved in benzine is also harmless, and the surface to
which it has been applied takes a good polish with a flannel
after drying. Professor Proctor has experimented with a
finish introduced by the Berlin Aniline Company some years
ago for coloured leathers, with apparently satisfactory results.
The preparation is practically a very hard stearine soap with
excess of stearic acid, and is made by boiling 8 parts of
stearic acid with 1 part of caustic soda and 50 parts of water
until thoroughly dissolved, and then adding 150 parts of cold
water and stirring till the material sets to a jelly. It is
applied very thinly with a sponge or rag, and after thorough
drying is polished with a soft brush or flannel. The alkali
present in the soap is useful in neutralising any mineral acids
contained in the leather. In very acid leathers it has been
noticed that the sodium sulphate so formed will sometimes
appear upon the surface as a white film, but this is easily
removed with a damp cloth, and the surface, after drying,
repolished with flannel.
Old books which it is desirable to preserve as long as possible in their
original bindings and books which will be used very little may be
treated with some form of preservative. If the book is to be much used,
it would better be rebound. Dr. Wire's experiments have been carried on
exclusively with law books. Whether the same processes could be used on
books bound in morocco or pigskin is something that has not yet been
determined. Most leather-bound books break first at the joint. The sheep
bindings in a law library would show signs of disintegration long before
the leather reached the breaking point, whereas the librarian would
first notice that morocco was decaying when the leather actually
cracked. Once cracked, no amount of preservative would do any good.
KINDS OF LEATHER[3]
The leathers that have been used in binding books have come from all
sorts of animals, but so far as the librarian is concerned the skins of
four animals only need be taken into consideration--the sheep, the cow,
the pig and the goat. In England some experiments have been made with
sealskin, but it has not been used long enough to give any definite idea
of its resistance to the encroachments of time.
Footnote 3: The prices of leathers given in the text are those
which prevailed during the summer of 1915.
SHEEPSKIN
Sheepskin is a soft, flexible leather with weak fibres, and with a
surface easily abraded. It has been used for bindings practically ever
since books were put into leathers; and, under the old methods of
tanning and manufacturing, proved satisfactory. In many libraries it is
possible to see leather books bound in sheep in the 17th century which
are in a good state of preservation. Even the sheep of the beginning of
the 19th century is frequently well preserved. Since 1860, however, the
quality of sheep has greatly deteriorated. This is bad enough, but
unfortunately sheep likes to masquerade under the name of morocco and
other leathers of a better grade, so that its use is much more extensive
than appears at first sight. In the process of imitation the grain of
the leather imitated is stamped on the skin. When this is done it
generally takes an expert to detect the fact that the leather is not
what it pretends to be, and even experts are sometimes deceived after
the leather is on a book.
The strongest sheepskins are made when tanned with oak bark. Sumac,
which is such a valuable tanning material with other leathers, is here
inferior to oak.
There are two kinds of sheepskin, the wool sheep which is known to all,
and the hair sheep which is not found in the United States, and which in
reality is a cross between a sheep and a goat. The hair sheep comes
from India, China, South America and Africa, generally from mountainous
districts. It has a much tougher fibre and is a better wearing skin than
that of the wool sheep. Unfortunately most of these skins, which are all
imported, are made into shoe leather. When properly tanned they are very
suitable for library binding, and their use for that purpose is
increasing.
The wool sheepskin in its natural color has been used for many years for
binding law books. It is seldom used for anything except government
documents and law books, and for this reason is known as "law-sheep."
_Roan._ Roans, the term used for sheepskins after they are dyed, can be
used advantageously on books which will be handled a great deal, and
which in any event will not stay on the shelves indefinitely. Properly
tanned and dyed, they make a satisfactory leather for a time, but their
life under the best of conditions seldom exceeds ten or twelve years.
While this is true of good roans, it unfortunately remains true that in
the United States, at least, it is difficult to get roans that are
properly tanned and dyed. Therefore, unless one is sure that the quality
of the skin is the best, he should use no sheep under any conditions.
_Skiver._ Skiver is the outside of a sheepskin which has been split, the
inner side being known as the flesher. It is a leather much used for
commercial binding, but since the splitting process takes away a great
part of the strength of the skin, leaving it not much stronger than
strong paper, skiver is wholly unfitted for library use.
COWHIDE
Cowhide, sometimes known as American russia, is a leather which has
increased enormously in use in the last twenty-five years. It is a
thick, coarse leather, rather unattractive in appearance, strong when
new, but with age rapidly deteriorating in quality, even when no
deleterious substance has been used in tanning or dyeing. It is a harder
leather to work than roan, but the quality is much more uniform and it
can be used advantageously for binding fiction and other books which
will be much used. In its natural state (undyed) it can be used in place
of law-sheep for law books, but has a tendency to become dark. It can be
obtained in many colors. Since it is too thick a leather to be used in
full thickness, practically all skins are split, and the amount of flesh
left with the grain determines the weight of the leather. A greater or
less amount is taken off according to the purpose for which the leather
is intended. Bookbinding cowhide costing 20c to 25c. a square foot is
the lightest weight leather that has the right to be called cow.[4] The
life of cowhide is from five to twelve years.
_Buffing._ Buffing is practically only the grain of cowskin from which
almost all the flesh has been split. It is not suitable for library
books, since it is very thin and begins to disintegrate in less than
five years. After it is on the volume it is hard to detect, so that some
library binders have been tempted to use it instead of cow. But as
buffing is never sold as cow, the library binder has no excuse for
keeping it in stock.
Footnote 4: This is the normal price of cow. The European war has
had the disastrous effect of raising the price and lowering the
quality. Until conditions become normal again all cowhide should be
shunned.
PIGSKIN
Pigskin is one of the strongest leathers, having a hard, resisting
surface and a good, tough fibre. In the grain, the holes which were left
when bristles were removed are plainly visible, giving the leather a
distinctive appearance, which can be imitated successfully, but which is
much less often imitated than the grain of morocco. If there be doubt of
the genuineness of pig, soak a piece of the leather until it has
absorbed a quantity of water, and then stretch it. If the grain pulls
out, it is imitation; if genuine, the bristle holes still show plainly.
Oak bark tanning is the best for this leather, and, since it is more
nearly gristle (less fibrous) than other leathers, dyes and chemicals
should not be used which will interfere with its quality of resisting
friction. It should be used in its natural color whenever possible.
Pigskin frequently comes in skins which are too thick for the binder to
work easily, or which are very uneven in thickness. In such cases the
paring down of the skin is likely to injure its strength. Because of its
thickness pig is generally supposed to be more suitable for large than
for small books, but inasmuch as several binders have used it
successfully for years on small books, it may be taken for granted that
it can be used with good results on all books, large or small, which are
to receive hard usage. It needs constant handling, and the absorption of
a certain amount of oil from the hands to keep it pliable. Otherwise it
dries rapidly and cracks along the joint. This, however, is true of all
leathers to a greater or less extent. Pig costs from 40c. to 45c. a
square foot.
GOAT
The leather which makes the strongest and most attractive binding comes
from the skins of goats and is called morocco, because it originally
came from that country. In the course of time goat skins from other
countries were tanned with sumac (originally a distinguishing
characteristic of a genuine morocco), but the same name was applied so
that we now have the paradoxical terms, Turkey morocco, Levant morocco,
etc. Moroccos have a beautiful grain, are flexible, soft and pliable to
the hand, and resist hard wear; qualities which contribute to their
great popularity.
Morocco varies greatly in quality as well as in appearance.
Unfortunately the skins which are best in quality, considering the
length of time they will wear, are not always those best in appearance.
The skins of goats with long hair from the colder countries make
beautiful bindings; but the skins of goats from the hot countries, such
as the interior of Africa, having short hair, while not so attractive in
appearance, are tougher and wear longer. In addition to the many grades
of genuine morocco there are as many more imitations of it made from
sheepskin, cowhide, etc. Only the expert can detect some of them in the
skin, and even he may be deceived when the leather is on the back of the
book.
In general it should be said that genuine morocco is the most expensive
leather that a library can use, and that it can be used to the greatest
advantage only occasionally. It makes an excellent binding for large
reference books which are constantly handled, for art books which must
be attractively bound, and for some periodicals which are much used in
reference work. It is not used nearly so much in libraries to-day as it
was ten or fifteen years ago, and it is quite safe to say that it will
be used less ten years from to-day than it is now.
_Levant morocco_, made from the skins of Angora goats, is the most
expensive and most beautiful leather used in binding. It has a large,
prominent grain, but is far too expensive for any library to use,
especially when it must be conceded that in its wearing quality it does
not equal that of some less expensive moroccos. Mr. Chivers' test showed
that so far as tensile strength goes, this leather is very much weaker
than many leathers much less expensive. When the skin has been subjected
to pressure until the surface is smooth it is known as "crushed levant."
_Turkey morocco_, made of skins of goats from Turkey, is a very strong,
durable leather which all libraries will find occasion to use from time
to time. It is very easily imitated. Under exposure to atmospheric
conditions existing in many libraries its life may not extend beyond
thirty years. In one library at least, where conditions of light and
heat were poor, the best Turkey morocco that the market afforded showed
signs of disintegration within twelve years. Good Turkey morocco can be
obtained for 35c. a square foot.
_Persian morocco_, which comes from the skin of a Persian sheep (not
goat), is not particularly attractive in appearance and is very poor in
quality. It is used extensively for commercial work, but is absolutely
valueless for library binding.
_Niger morocco_ is a goat skin which comes from the interior of Africa,
generally by way of Tripoli, and is by no means a recent discovery,
though we knew little about it five years ago. It is tanned by natives
according to some method of vegetable tanning not completely known at
this time. While in appearance it is not so attractive as some other
moroccos, because of blemishes due to carelessness in handling and to
the imperfect removal of some of the hairs, it has been proved by the
tests made under the direction of Mr. Chivers to be stronger than all
other moroccos; the inference is that it is more durable. Until recently
it has been very hard to obtain in the United States.
_Bock morocco_ is not a morocco but a split Persian sheep so poor in
quality that it is mentioned only to be condemned.
CALFSKIN
Calfskin in all its various characters, such as divinity, kip, marbled,
mottled, smooth, tree, or just plain calf is a very beautiful leather
much used in the past for binding books for individuals. For this
purpose it has, of late years, been crowded out by Levant morocco. It
has a soft, smooth surface which disintegrates rapidly under the action
of heat and gas and has little strength even for temporary use. For the
library it is useless.
RUSSIA LEATHER
This is a brownish-red leather made from the skins of different animals,
tanned with willow bark and filled with a preparation of birch oil which
gives it its peculiar odor. Neither in its genuine form nor in imitation
is it a useful leather for libraries.
SEALSKIN
Although experiments have been made with it in some English libraries
sealskin has never been much used in the United States for library
binding. It is made from the skins of the hair seal, the supply coming
from all parts of the North Atlantic Ocean. According to Mr. Douglas
Cockerell and other binding experts in England, the skin is peculiarly
suited for library use. It is reported to be a hard-wearing leather,
tough and pliable, even in quality so that no part of the skin must be
discarded because too thin or too weak, and possessing a beautiful
grain. The price ranges from a point somewhat higher than that of the
poorer moroccos to one somewhat lower than the higher prices.
Unfortunately it can be easily imitated.
VELLUM
Probably no discussion of leather is complete without mentioning vellum,
a binding material which does not resemble leather, but which
nevertheless is made from calfskin or sometimes from goat skin. It is
prepared by the use of lime, and as far as the actual wear on flat
surface is concerned, is perhaps better than any leather. It is,
however, very susceptible to moisture, which makes it warp; and to
light, which makes it hard and brittle. Since it is very hard, does not
bend easily and is hard to work, its chief use is on the corners of
books to protect them and make them less likely to break or rub. Large
libraries have used it somewhat for this purpose, but the use is dying
out.
In making a study of leathers it is well to obtain samples of all kinds,
including those which are unsuitable for library use, and to examine
them carefully, noting the appearance of the grain, thickness of skin,
flexibility, and softness of surface. Perhaps more money can be wasted
through ignorance of the comparative values of different kinds of
leather which it is permissible to use in library binding, than in
mismanagement of any other part of binding.
CLOTH
Cloth is fully as important as leather in the economy of binding.
Several years ago it was the custom to bind periodicals and other books
which were used comparatively seldom in leather, while fiction,
juvenile and other books which wore out quickly were bound in cloth.
Recently the opposite course has been more favored. Books which receive
unusually hard usage and are in the hands of readers constantly are
bound in leather; while those which are used seldom, including
periodicals, are bound in some kind of cloth. Without doubt the change
is a wise one. Even the best of leather disintegrates in time under the
action of heat, gas, light, etc., and to-day many a volume bound in
leather ten or fifteen years ago has parted from its sides,
necessitating rebinding or recovering. Had it been bound in a good
quality of cloth it would to-day be in good condition, and probably
would remain in good condition for a hundred years. It requires
considerable courage to change the binding of a good set of a standard
periodical, such as the Atlantic or Harper's, from an attractive half
morocco binding to an unattractive buckram. Unquestionably, if economy
is an object, the change should be made, except possibly in the case of
a library which uses these periodicals daily. Every librarian must
decide each case for himself strictly according to the use the set is to
receive, always bearing in mind the fact that leather disintegrates with
time, whereas cloth does not unless exposed to excessive moisture.
No cloth which is suitable for library use is perfectly satisfactory
because it has not the strength of good leather, cannot be used
advantageously on very heavy books, soils easily and with use grows soft
and flabby, especially along the joints. But on the other hand even
those not suitable for libraries which are used by the publisher on
cheap books are much better than poor grades of leathers, such as
skiver, bock, buffing, etc.
The requisite qualities of a good cloth are:
(_a_) Endurance when folded back and forth in the same place, so that it
may withstand the wear at the joint caused by opening the book.
(_b_) Smoothness, so that there will be a comparatively small amount of
friction when withdrawing a book from between two others on the shelf.
(_c_) Ability to withstand constant rubbing back and forth on tables.
(_d_) Color that is fast when exposed to light; if possible it should be
fast to water also, though this is less important.
(_e_) Color should be dyed in the piece, not pressed in by machinery.
Many cloths have some of these qualities but few have all of them. So
far as is known to the writer only the grade of cloth described on page
77 has the last qualification.
Practically all cloth used in the United States is made of cotton. The
best cloths are manufactured by The Holliston Mills, Norwood, Mass.; The
Interlaken Mills, New York City; The Joseph Bancroft & Sons Company,
Wilmington, Del., and by the Winterbottom Company and the Manchester
Book Cloth Company in England. Since a number of grades are made in
several different patterns and a great number of shades for each grade
and each pattern, a variety of choice is permitted. As a matter of
fact, however, most librarians select a good grade with a regular weave
and confine themselves to a few standard shades, such as dark green,
brown, red, dark blue, and tan.
Since the strength of the warp is much greater than that of the weft, it
is advisable when possible to cover books with the warp running across
the cover. This, however, may entail some hardship on the binder for it
may frequently happen that in order to cut his cover economically he
must make the warp run lengthwise of the book. If a strong cloth is used
the advantage is not great enough to be insisted upon.
Each of the American firms mentioned makes three distinct grades, all of
which libraries may use. Each firm uses a different name for each grade.
In other words, there are no general names which can be used for the
corresponding grade in all makes. Therefore for the purposes of this
chapter these cloths will be considered under the heads of Grades 1, 2
and 3, but it must be remembered that this is an arbitrary designation
not known to the trade. Under each grade will be given the specific
names used by the three manufacturers.
GRADE 1
Grade one of cloth, the cheapest that a librarian may use, is not made
of the best quality of cotton thread and should never be used under any
circumstances for full binding. It may be used on the sides of books
bound in leather; if this be done the corners should be covered with
vellum, for this cloth does not withstand hard usage and is likely to
fray at the corners. It is a cloth commonly used by publishers, but
should be used sparingly by the librarian. "Art vellum" made by the
Interlaken Mills, "Aldine vellum" made by the Holliston Mills, and
"Linen finish" made by the Joseph Bancroft & Sons Company, come within
this grade.
GRADE 2
(_a_) Grade two is made of a better grade of cotton and with a closer
weave than the preceding, but is not sufficiently strong to be used for
full binding. It can be used more satisfactorily than the preceding on
the sides of books bound in leather or duck. In common with all cloths,
except the buckram made according to the government specifications
(which will be discussed later), the different colors are not made, as
one might suppose, by dyeing the cloth after it is woven, but by mixing
the color with the sizing or starch which is used in finishing the
cloth, and pressing it into the cloth by machinery. As a natural result
the color rubs off with wear and the natural gray of the original cloth
as first woven appears. "Art canvas" made by the Interlaken Mills,
"Classic buckram" made by the Holliston Mills, and "Polished buckram,"
by the Joseph Bancroft & Sons Company come within this grade.
(_b_) _Buckram._ Under the name of buckram various grades of cloth are
manufactured which resemble to a greater or less degree those mentioned
under Grade 2 (_a_). Generally it is a coarsely woven cloth stiffened
with glue or sizing, and the term originally indicated that the cloth
was made of linen. At the present time linen buckram made in England can
be obtained, but all that is manufactured in the United States is made
of cotton. Linen buckram costs much more than cotton and it is doubtful
if it is any more serviceable. All of the three manufacturers mentioned
make buckrams.
GRADE 3
Prior to 1907 the Congressional set of government documents distributed
to the depository libraries had been bound in sheepskin and the leather
on the volumes had disintegrated so much as to make the set a hard one
to care for. In 1907 the Congressional Printing Investigation Commission
asked librarians of depository libraries to suggest, without considering
cost, suitable binding materials for Government Documents. The number of
replies received was 124, embodying suggestions as follows: full sheep,
11; half-russia, 78; cloth, 25; buckram, 70; linen duck, 20; canvas, 19.
Some librarians expressed more than one preference, so that the total
number of preferences was greater than the total of those replying. Most
of those who favored sheep did so because of their desire for
uniformity. Those who favored half-russia undoubtedly desired half
American russia, or cowhide. 134 expressed preference for some form of
cloth.
After receiving the replies from librarians the Printing Investigation
Commission obtained samples of cloth from various cloth manufacturers in
the United States and the Bureau of Standards made a series of chemical
and physical tests to determine the durability of these cloths. Chemical
tests were made to discover whether the colors were fast when exposed to
light. It is to be regretted perhaps that no tests were made to
determine whether the cloths were fast to water and that this
qualification was not included in the final specifications. Admitting,
however, that a cloth which is fast to sun and water both is a valuable
cloth for bookbinding, it is evident that the quality of fastness to
water is not a vitally important one for cloth used in the United
States. The total number of books injured by water is so small as to
make insistence upon this quality entirely unnecessary. If books become
so soiled that they need to be washed they should be bound in waterproof
cloth.
Because many volumes of Government Documents are sent to Porto Rico and
the Philippines where insects eat almost anything of an animal or
vegetable character, the desirability of the cloth as an article of diet
for insects, was also tested.
The physical tests indicated:
_a._ Number of threads per inch of warp and weft.
_b._ Absorption of moisture.
_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 documents
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 assistants 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 x 30 and 23 x 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 circumstances. 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.