especially large quantity of gum or mucilage, but which have not come
into use for preparing marbling size on account of their cost and of the
less consistency of their mucilages.
The richest in this regard are the seeds of quinces and linseed. Their
mucilage is as viscous as that of flea-bane. Much less gum is contained
in the leaves of mallows of colts-foot or of marsh-mallows.
In closing this chapter upon the mucilages of plants and their
applications as sizing for marbling I again recommend carrageen moss as
the best size, because it has given me during my investigations and in
practice, surprising results of its usefulness for all kinds of marbled
edges.
OX-GALL.
OX-GALL.
THE CHEMICAL CONSTITUENTS OF OX-GALL.
In the bile of every animal are two peculiar acids both containing
nitrogen. One of them free of sulphur, the other containing it, both by
boiling with acids and alkalis yield the same acid free of nitrogen,
which is called cholic acid.
If these two acids be separated from each other in a chemical way we
obtain glycocholic acid, an acid free of sulphur and the other
taurocholic acid containing sulphur. The alkali salts contained in bile
are quite soluble in water or alcohol but insoluble in ether. To produce
it in a pure state mix the bile with as much animal coal, (spodium) so
that finally, on evaporation in the water-bath a dry powder results,
from which is drawn, by the use of absolute alcohol, the now colorless
cholic acid esters, cholesterine, choline, lactic acid, etc. When ether
containing a little water is added, the cholic acid esters are
precipitated as colorless plaster-like masses and crystallize, when left
in the fluid for some time.
The so-called crystallized bile is the final material for the
preparation of acids. The acids of ox-gall have been investigated in the
most thorough manner.
Glycocholic acid is obtained as a colorless precipitate from a watery
solution of crystallized ox-gall, by adding dilute sulphuric acid until
the fluid becomes flocculent, which after a while, especially, if the
water contains a little ether, is changed into a voluminous 'magma' of
fine white needles.
If collected upon a filter, these needles unite and form a lustrous
felt.
Glycocholic acid is sparingly soluble in water but soluble in alcohol.
It forms the principal constituent of bile, it reacts feebly with acid
and tastes bitter-sweet. Taurocholic acid is found only in small
quantities in ox-gall and has no important effect on the colors.
THE EFFECT OF OX-GALL UPON COLORS.
By chemical analysis we have seen that glycocholic acid is the principal
constituent of ox-gall and in combination with taurocholic acid, glycin,
choline and lactic acid is soluble in water. On the other hand, when
pure, it is soluble with difficulty and therefore is only of use to us
when in combination with other acids, as it must combine intimately with
water-colors.
The atomic weight of gall and the insolubility of pure glycocholic acid
in water are the most valuable properties of it for the marbling colors.
The first gives to the colors the expanding power, the latter the
adhesion to paper.
All the lower fatty acids, among which ox-gall may be numbered, possess
properties similar to fatty bodies, namely a less atomic weight than
water. They differ from fatty bodies in this, that they mix with water.
The expanding power and lightness of ox-gall are, consequently,
peculiarities of equal value. Marbling size forms the base for the
colors, which by the consistency of the glutinous mass and by the gall
added to them are prevented from sinking to the bottom. They float like
drops of oil upon the water and only differ from them by the fact that
the colors will spread out on the size, while the drops of oil on the
water are contracted to circular spots of small size. If a drop of oil
were thrown upon the size it would spread out very quickly.
This purely physical occurrence is caused by the different weights of
the bodies and the consistency of the size. The fatty bodies, which are
much lighter than water, float upon it but the gravity of the drop
itself prohibits its spreading out, as it sinks somewhat and is held
together by it. It is different with the size; by the consistency of the
glutinous mass the gravity of the drop is antagonized and as a result it
flattens and spreads out.
As I have already mentioned the insolubility of glycocholic acid binds
the color to the paper. To explain this I will mention a few examples;
the saturated alum solution will cause glycocholic acid to curdle. If,
therefore, we add to ox-gall which is basic the saturated solution of
alum, a soft plaster-like mass is precipitated which consists of
glycocholate of aluminium, insoluble in water. This chemical reaction
explains the durability of the colors. If we desire to marble books or
papers we impregnate them with alum water, allow them to dry partly and
take the edge from the size.
In the same moment that the paper soaked with alum comes in contact with
the colors, the latter become bound by the formation of glycocholates of
aluminium and do not run. They have the same property of fixing colors
that resinous soaps used in the paper manufacture for gluing machine
paper have. If this resinous soap were not too strongly basic, which is
injurious to many colors, it might be applied as a surrogate for
ox-gall.
As the resinous soap on account of its binding quality and insolubility
could also be used in marbling with such colors, upon which it exercises
no injurious effect, I will here give its preparation and former use in
the manufacture of paper. If 2-5 ounces of rosin be boiled with 1-1/3
ounces of sodium lye and if you add by teaspoonful from time to time so
much lye until a sample of it is dissolved by hot water to a clear
fluid, the mass on cooling congeals and forms a quite solid soap. If we
mix a solution of resinous soap with one of alum then we obtain an
insoluble compound of resinous acids and aluminium. In this way
resinous soap is used in gluing paper by adding to the paper pulp, first
resinous soap and then a solution of alum. During this process a thin
layer of insoluble soap of aluminium is formed around every particle of
the paper and thus the running of the ink is prohibited. The same
process occurs with ox-gall contained in the colors, when the edge is
lifted off on paper or book-edges impregnated with alum, by which the
running of the colors is prohibited.
THE PREPARATION OF OX-GALL AND ITS USES.
The preparation of ox-gall to be used in marbling is simple. Take a
quart of fresh bile (ox-gall or fish-gall), place in a bottle which
contains when filled from 1-1/2 to 2 quarts, add 1/2 pint of absolute
alcohol, shake well and leave stand for from 14 days to 3 weeks. Within
this time all particles of gum and all fatty substances which are
present in some galls in comparatively large quantities, will fall to
the bottom and the gall will be thin-fluid, pure and diaphanous,
brownish, yellow or greenish according to the nourishment of the animal
from which it was taken.
Cow-gall contains more gum and fatty substances, than ox-gall;
fish-gall, on the other hand, is thinner than ox-gall and would be the
most useful of them all, if it could be obtained in sufficient
quantities. If the gall is thin and pure it is filtered through paper
which is easily and quickly done as it runs like water. If by filtering
the dregs of the gall the filter should become clogged, a new one must
be used.
The addition of alcohol causes the precipitation of glutinous and fatty
substances and preserves the gall from decomposition. If prepared in
such a way it can be preserved for years without spoiling.
All colors which we intend to use for marbling must be bound to bodies
absolutely insoluble in water; it is therefore a mistake to say, that
the colors dissolve in water. You may grind the color on a marble slab
or in a machine as long as you please, but you will only obtain a great
degree of fineness of the bodies but never a dissolution of the same.
Each body possesses its limit of divisibility; in amorphous bodies the
high divisibility is but natural, but in crystalline bodies this
division must be produced by grinding or washing.
The gall does not combine with these bodies, nor does it penetrate them,
but only clings to them loosely. It can be readily removed in case the
colors should be rendered useless by the addition of too much gall. The
color is allowed to precipitate in the bottle and the water standing
above is poured off, fresh water is added and this manipulation is
repeated several times.
The gall which surrounds every particle of color forms, as it were, the
support of it and adapts it to float upon the size.
Bodiless colors, which give a complete solution with water will run
into each other on being thrown on the size and will flow from the paper
when it is lifted off. The insolubility of the color bodies therefore
prevents them from running although they are disarranged on the size in
drawing and although one color may be compressed or expanded by a
second, yet they all remain separate without mixing, except, perhaps,
that the shade of the first color becomes more intense, because its
color particles are pushed together by the more violent expansion of the
second color.
From this it will be seen that the colors, to be useful for our
purposes, must be thoroughly insoluble. The gall is added during the
process of grinding the color, so that the particles of colors are fully
surrounded by the gall. The gall has an excellent effect on the colors
but it also can act very injuriously if the necessary precautions are
not taken. Carelessness is mostly the reason that the edges do not
possess the demanded lustre of color and why they appear pale, as the
marbler often uses the gall too soon when he notices the smallest
obstacle, (due in most cases to the size.) It is therefore not
astonishing that brilliant comb or peacock-edges are so rarely seen.
It is an obstacle to marbling, that the gall mixes so easily with the
size. It often happens that the gall spoils the size before an edge was
ever produced on it. This happens especially when the size on which the
colors are prepared according to the old method, is too thick. The size
is frequently soiled and spoiled when the colors are prepared, because
the colors can not be perfectly drawn off on thick size. There will
always remain some particles which will not only soil the size but
impregnate it with gall, and which will cause the entire uselessness of
size and color.
A very consistent size will make the preparation of colors extremely
difficult, as they need a double quantity of gall for the purpose of
spreading out. If there is but one color used, the preparation on such a
size would be possible without spoiling it, but with four colors this is
entirely impossible because the repeated drawing off of the colors,
which always leaves particles behind, will, by and by, impregnate the
size so that when the fourth color is prepared the first will not spread
out any further.
The more the impregnation of the gall and size increases, the power of
expansion of the colors decreases and this continues until both
materials are useless.
It is therefore advisable, as I have already stated, in the chapter upon
the varieties of sizes that the colors should be prepared separately on
a small part of size to determine the correct consistency of the latter
and to prohibit the whole size being soiled.
The gall should be kept in a small bottle containing about 1/10 quart
with a perforated stopper from which a small tube protrudes and from
which the gall can be added to the colors in drops.
Although the preparation of the color in this way takes more time, this
trouble is amply repaid by the result.
Fatty bodies are injurious to the size, therefore they must be carefully
avoided because they have the same effect as the gall, they form,
although not insoluble in water, a combination with the size and
prohibit the colors from spreading out. Fatty bodies can be transferred
by glutinous fluids into a state of the most minute division and they
then form emulsions.
Natural emulsions are milk, the yolk of egg, and the milky saps of
plants. For this reason, in many establishments raw milk is used as a
propelling medium for hair-veined edges.
There are also fatty bodies which, in an artificial way, form an
emulsion even with water; for instance, almond, poppy and hemp, if they
are ground to a pulp with a little water yield a milky mixture. All
these emulsions artificial as well as natural, can be employed as
expanding mediums and give better results for marbling than petroleum or
naptha.
Substances Acting Similarly to Gall.
SUBSTANCES ACTING SIMILARLY TO GALL.
There are rosins which are soluble in ammonia or borax. These solutions
possess properties similar to gall and either can be used as an
expanding medium or as an addition to colors. Different experiments with
these solutions gave very good results.
To produce them pour a quart of water into a vessel, warm, add 2/5 of an
ounce of shellac or rosin and a 1/100 part of a quart of ammonia or 2/5
of an ounce of borax so that the rosin becomes dissolved, and then bring
the mixture to a boiling temperature.
Ammonia dissolves the rosins much more quickly and thoroughly than
borax, but the solution in ammonia has the property of gelatinizing the
colors after they have remained standing a short time. They therefore
can only be used in a greatly diluted condition. The borax solution, on
the other hand, has no such effect; not even the concentrated solution.
I mention these two solutions especially, to instigate further
investigations.
SPRINKLING WATER.
SPRINKLING WATER.
Sprinkling water is one of the newer discoveries in the art of marbling
and deserves full consideration on account of its good properties. Its
advantages consist in this, that it produces circular forms upon the
size and has a greater expanding power than gall.
Sprinkling water is used for hair-veined edges and as an addition to the
ground color in marbling.
To prepare it take 1-1/2 ounces of Venetian soap, finely chipped, place
them in a pot with a quart of alcohol, warm up some water in a second
and large vessel in which the pot containing the alcohol and soap is
put, bring the whole to boiling, when the soap will be entirely
dissolved in the alcohol. Keep a quintuple quantity of water in
readiness into which the solution of soap is poured and stir well, the
sprinkling water is then ready for use. The solution of soap in alcohol
is carried out in a water-bath to avoid the ignition of the volatile
vapors which are generated by this process. The alcohol prevents the
foaming of the soap, the soft water the curdling.
The solution when ready is to be kept in a closed bottle.
Generally to the colors which are used for hair-veined edges and marble
more gall is added than to those used for drawn edges. It is, therefore,
easily understood that with these, a more intensively acting expanding
medium must be used to spread out the strong colors into veins.
The sprinkling water is here of great service, because, although ox-gall
in its pure state possesses a sufficient expanding power it is here more
desirable to produce beauty of forms. In this respect the gall is much
inferior to sprinkling water, the former producing all kinds of forms,
the latter only beautifully round and oval ones.
For marbling, the ground color is prepared with gall so far, until it
slightly pushes the other colors aside and then, by and by, so much
sprinkling water is added until the desired expanding power is reached.
Every ground color which is prepared with sprinkling water spoils on
standing two or three days becoming slimy and viscous, and, for
economy's sake, not more color should be prepared with sprinkling water
than is required for one marbling process.
For hair-veined edges, the sprinkling water is used in the same way as
gall. Use a large painter's brush or whisk and move the colors by
beating into veins, with this brush or whisk through a slot, or throw
the sprinkling-water upon the color by means of the sprinkling brush and
sieve. In both cases the same result will be achieved.
ALUM WATER.
ALUM WATER.
In the chapter upon gall I have mentioned in a general way the action of
alum water upon the edges, it remains only therefore to explain the
preparation and application of the same.
To achieve beautiful results from the colors it is indispensable to wet
the book edges or the paper, to be marbled, with concentrated alum
water, so that no spot is left free from moisture, because at that spot
the color would not take.
Concentrated alum water is prepared in the following way; put 2 quarts
of water and 13 ounces of alum into a pot and heat until the alum is
entirely dissolved. This concentrated solution is permitted to cool and
is bottled tightly.
A solution of alum in cold water is much too weak for the above purpose
as alum is but sparingly soluble in cold water.
The book edge or paper, which is to be marbled, is wet with a sponge
dipped into this cold concentrated alum solution and must be allowed to
dry for from 5 to 8 minutes, after which the produced edge may be lifted
from the size. Generally this point finds but too little consideration
in our book-binding establishments.
Edges which have not been treated with this alum water show as a
consequence poor and blotted results, although such little trouble is
necessary to wet the edges with alum water.
With hair-veined edges, where colors are thrown on the size only in very
small quantities, this wetting may be omitted; but with comb, peacock
and bouquet edges, for which four to six colors are used, it is
unavoidably necessary to prepare the edges with alum water because the
glycocholate aluminium formed by the color while in connection with the
alum water is essential to fix the color in such quantities.
Therefore, if it is desired to produce clean and lustrous edges in which
the white lines appear without a trace of color, then this advice is to
be followed, the small trouble being amply repaid by the beauty of the
edges.
Ordinary earth and several of the lake-colors take without wetting of
edges with alum water, but these colors leave much to be desired in
their divisibility and fineness and always appear rugged.
A much finer fixing medium is the acetate of aluminium which can be
easily produced.
Dissolve 1 pound of alum in 3 quarts of warm water, prepare another
solution with the same quantity of soda, mix these two, whereupon the
hydrate of aluminium is precipitated. Allow the latter to settle, pour
the water above carefully off, and filter; the white body which remains
consists of hydrate of aluminium which is readily dissolved by a little
acetic acid, into a clear fluid and can be diluted with the same volume
of water. Then heat the whole liquid, when the excess of acetic acid is
evaporated, we have the desired acetate of aluminium which can be used
in the same way as alum water.
Edges and paper which are to be marbled should only be moistened with
alum water or aluminium acetate shortly before the marbling and should
stand not longer than a half-hour after the sizing of the edges, because
later on, an insoluble layer is formed which only takes color with great
difficulty. It is therefore best to prepare the colors before commencing
the sizing of the edges. If there are a large number of books, it is
better to divide them into two or three lots.
The Preparation of the Colors for Marbling.
THE PREPARATION OF THE COLORS FOR MARBLING.
The want of knowledge of colors gave me the greatest trouble when I
began their manufacture as I had no information as to why this or that
color was unfit for marbling.
The numberless experiments I made to this end remained without results.
It was an exceedingly great trial to my patience, but by the pertinacity
with which I clung to my investigations, I, at last, succeeded in making
the important discovery, that the real value of color for marbling
purposes is its body and that the color itself, which is bound to the
body either naturally or chemically, is of less importance. By this
discovery every difficulty that I had so long experienced was cleared
away and it was made manifest, why it had been impossible for the
marbling art to become sufficiently popular.
From this time on I had a foundation, upon which to continue my
investigations with greater surety. Finally I succeeded in finding that
the colors named later on are good and useful marbling colors.
When we look over the different special branches of our trade, we find
everywhere great progress, which is even noticeable in the smallest
workshop. Already, these wonderful achievements have become common
property, only the art of marbling stood still on account of
insufficient instruction and it has not made any progress in the last
decade. This was due to a large number of men in our trade using
mechanical marblers to avoid those obstacles, which had hitherto offered
themselves in marbling.
The expectations which were placed on the mechanical marblers were not
fulfilled, because, after a short use, and when not carefully kept
clean, they became sticky from dust and color mixing so that they gave
but very indifferent productions. The necessity of continually cleaning
these mechanical marblers and their lack of uniformity are by no means
recommendable properties.
Mechanical marblers should be retired to small book-binderies for use
upon single books, where they are eminently in the right place, driving
away the primitive sprinkled or starched edges.
The interest which was shown in mechanical marblers is a proof that all
members of our trade, who use them, possess a liking for the marbling
art and would be zealous friends of the same, if they but knew of the
methods of marbling, that would give beautiful results without great
difficulty.
To judge rightly the value of a new invention, we have only to see,
whether it is introduced into the wholesale trade and is in continual
use. This is the best test of inventions and the only proper basis,
upon which to judge them correctly. We find the mechanical marblers
exclusively in the small shop, because they do not answer the demands of
the wholesale manufacturer in any way.
What the marbling art is able to offer, a person can only judge, who has
seen exemplary edges and to whom marbling is not a stranger. No kind of
edge, to which color is applied, can be compared to the effective
splendor of marbled edges. In thousands of variations it imitates nature
and delights the eye by its products. Although marbling has hardly
reached the middle rung of the ladder of its development, it to-day
stands unrivalled.
It is clear, that such an art should be fostered and nursed, if it is to
grow to its full development. But here the investigation of one man is
insufficient, a general interest is demanded and I hope, that this will
be aroused by my work. After this slight diversion I will now begin to
treat my real subject, the preparation of colors, and for that purpose,
I will divide the marbling art into three important parts: the size, the
color and the technical application.
The size and the technical application of the colors demand great
attention and practice; on the other hand, the preparation of colors but
labor. The colors are divided into two groups, mineral and lake colors.
In the lake colors, if they are good and strong, the coloring matter
bound to the metallic oxides is equal to one-half of the whole weight of
the color, therefore they can be prepared as good marbling colors
without adding anything but gall. On the other hand, in mineral colors,
which in a natural or chemical way are bound to bodies, the body weighs
much more than the coloring substance and even if the metallic oxide is
the real coloring substance, as is the case with ferric hydrate, the
organic coloring matters derived from the vegetable or animal kingdom
are preferable to the inorganic substances.