Naples yellow, graduated as nicely to some old ivory model as possible.
It is best not to have it all too uniformly of one tone, since old work
often has its shades. The object here need not be to ape or copy old
work, but to catch what is beautiful in it. Then fill in the outlines
of the pattern, and the dots and irregularities near it, or anywhere,
with brown more or less dark. For this, study old ivory. Then varnish
with SOEHNÉE, No. 3. A great deal depends on the quality of this second
coat. Finally rub down very thoroughly with chamois and hand, and
repeat the process more than once if you want it very much like ivory.
Very extraordinary and perfect imitations of ivory, bone, worn and
glossy parchment and brown leather, wood, marble--in short, of any kind
of work of art which has been rubbed and worn smooth by hand during
centuries, can be made by this process of ivorying with alternate
layers of varnish, colour, varnish, and so on.
When there is no relief the paint itself can be worked with wheel and
tracer, and then repainted and varnished. This is a very beautiful art,
specially applicable to book-covers, and often useful in repairing old
work. I would here repeat what I said, that the object of imitating
effects in old works of art, or in other kinds of art--which is so
staunchly repudiated by mere artisans who themselves are generally
only imitators of the designs of others--is not to make counterfeits,
but to take from age or art beautiful effects, however produced,
and apply them to work. Those who are too conscientious to execute
stencilling on a wall, or to use moulds for leather-work, would do
well to first consider whether they _know enough_ to design a really
good or admirable stencil, or an excellent mould, for it is in the
genius which originates and executes, not in the mere means, tools, and
materials employed, that art consists. Art does not depend in the least
on either making skill difficult or in rendering its methods easy; it
displays skill, but scorns the Chinese standard of mere industry. An
artist like ALBERT DÜRER would never have prided himself on only using
certain tools as being “artistic;” he would, however, have made designs
which would have forced originality and art into a photograph. There
are marvellous effects of corrugation in ancient walls, plays of light
and shade and colour and polish in rock and strand and heaps of ashes,
which LEONARDO DA VINCI knew how to catch and transfer to different
subjects, and at which perhaps the artisans of his time sneered as “not
artistic.”
Age, which gives a certain exquisite charm to wine and words of wisdom,
has done the same to all material things, of which, indeed, it may be
strangely said that wherever it does not destroy a charm it confers
one, like moonlight, which renders nightly shadows more terrible or
else more beautiful.
It is to be regretted that this principle, which is a very important
one, is but little understood. The manufacturers of all decorative
art work at present endeavour without exception to make everything
staringly, cruelly brand new, or else a mere copy of old work. What
they need is to draw, as REMBRANDT did, from age so much of its
peculiar charm as is adaptable to modern work.
I have introduced these remarks because the mender and restorer of old
ivories and bookbindings and pictures, if he regards his occupation as
an art--which it really is--is peculiarly adapted to fully appreciate
them. Restoring, like copying, leads to creating new work. I think that
any person of ordinary intelligence can, with zeal and application,
learn to mend anything as described in this work, and from such mending
it is much easier to learn to make works of minor art. “Short the step
from senator to _podestá_--shorter the step from _podestá_ to king.”
A great merit and peculiarity of ivory, as of horn, is that it is
tough and elastic, as well as of a beautiful transparent or diaphanous
quality. These characteristics have, with the exception of its graining
or texture, been well imitated thus far only in _celluloid_, which is
unfortunately too expensive for very general use, and, what is worse,
too liable to destruction. I, however, confidently anticipate that
ere long some substance will be discovered much superior to celluloid
as a substitute, and probably much cheaper and less perishable. To
_celluloid_ I may, however, add the sulphuretted preparations of
caoutchouc and gutta-percha, known as vulcanite or ebonite. These are
indeed hard, tough, and elastic to perfection, but very dark and opaque.
LEHNER, in his work _Die Imitationen_, observes that imitations of
ivory must be varied to suit the colour and quality of originals.
This requires a study, firstly, of the adhesive or glue which is to
be used. This, when colourless, is known as French gelatine, and is
very expensive. In lieu thereof the experimenter may take best white
Salisbury glue or gum-arabic prepared with alum-water. Secondly, the
body, which may be of carbonate of magnesia, carbonate of lime, such as
powdered marble, sulphuretted lime, or powdered gypsum, chalk, starch,
or flour, white oxide of tin, zinc, sulphate of barytes or Chinese
white, white oxide of lead. In combining, _e.g._, magnesia with the
glue, an addition of ten per cent. of glycerine gives elasticity and
a horn-like clearness. To harden artificial ivory made with glue, the
objects are dipped into strong solution of alum or tannin for about
four minutes. The tannin is best made from gall-apples. Objects thus
made have an antique ivory, yellowish hue. Red chrome alkali may be
used in solution with water instead of tannin, but it gives a stronger
yellow.
According to HYATT’S patent, artificial ivory is made by combining a
syrup made of eight parts shellac and three parts of ammoniac with
forty of the oxide of zinc. This is heated and subjected to pressure.
CELLULOID is the best material for making artificial ivory. It is made
by the combination of cellulose or vegetable fibre in the form of
cotton-wool treated with acid; that is to say, gun-cotton and camphor.
It is sold in thin leaves, &c., which can be softened at from 100°
to 125° centigrade, so as to be moulded to any form. By infusion of
colouring matter, such as oxide of zinc, cinnabar, &c., celluloid is
made to resemble ivory, coral, or tortoise-shell. It has often been
applied to making a perfect imitation of Florentine mosaic, and of
course serves admirably to repair such work when broken.
A very strong cement for ivory, bone, or fine wood is made by boiling
transparent gelatine in water to a thick mass. Add to this gum-mastic
dissolved in alcohol, this solution being one-fourth, and stir into
it pure white oxide of zinc till it forms a fluid like honey. This is
also of itself an artificial ivory, when prepared and dried in the
mass. Another can be made by combining diamond cement (_vide_ Glass)
with powdered ivory and a little glycerine. Also with the same, or
very strong white glue and powdered egg-shells, which latter should
have been boiled. Also white of egg, gum-arabic, a very little strong
vinegar, and levigated egg-shells.
Another recipe for such mending or making of ivory and similar
substances is to take soft and very white paper in pulp, combined with
cotton-wool, treated with very dilute acid or _strong_ vinegar. To
this add powdered egg-shells, made into paste with a little glycerine;
amalgamate this with the paper and cotton mixture as thoroughly as
possible, and submit to strong pressure or rolling.
CELLULOSE in any form, whether made from cotton, linen, wood, or other
vegetable fibrous substance, affords a basis which can be treated
with dilute acid to produce a horny or parchment-like substance. A
modification of this is seen in making celluloid with camphor. These
modified forms of organic creation can be combined with other organic
substances or minerals in great variety. Thus glycerine, and at times
oil of different kinds, in such admixtures confers elasticity, or a
diaphanous appearance; ivory-dust has an affinity for oil and glue; and
these all combine with parchment, boiled ivory-dust, and fibrine or
cellulose.
Certain marine plants, such as _kelp_, yield a fibrous substance which
has very peculiar qualities, and which admits of ingenious combination.
Certain experiments and observations convince me that there is here
a vast field, as yet unexplored, in which science will yet make
discoveries and afford valuable contributions to technology.
The reader who is specially interested in this subject may consult to
advantage _Die Verarbeitung des Hornes, Elfenbeines, Schildpatts und
der Perlenmutter_, &c., von Louis Edgar Andés; Vienna, A. Hartleben,
price 3s.
REPAIRING AMBER
HOW TO PERFECTLY RE-JOIN BROKEN AMBER, AND TO IMITATE IT--HOW TO MELT
AMBER IN FRAGMENTS TO A SINGLE BODY
Amber has been admired in all ages and everywhere from its exquisite
colour and semi-transparency. Many superstitions were attached to it,
and many still believe that to carry a bead made from it is good for
the eyesight. It is principally found on the Prussian coast, off the
German Ocean, but is also picked up in considerable quantities on the
English shore. It is the gum or resin of a now extinct species of pine,
which was probably much like that in New Zealand, which produces the
gum _kauri_, which so much resembles amber.
Some amber is yellow and clear like lemon-candy. This is extensively
imitated for cigar-holders and pipe-mouthpieces, beads, &c. Then there
is the clouded, varying from white to straw-colour, and the beautiful
golden-brown, which appears so rich in sunlight; also the dark-brown
and black. These dark-brown ambers are generally seen in old ornaments,
and are of a kind which is dug out of the earth. Light amber can be
darkened to brown by an artificial process.
Gum _copal_, which comes from Africa, much resembles amber, but is less
beautiful and more brittle. Gum _kauri_, from New Zealand, is very much
like it. Both are used to imitate amber.
There are not many who know how to mend amber when broken. I am assured
that the following is a trustworthy method:--Warm the pieces, dampen
them with caustic potash (_ætz-kali_), and then press them together.
When well done the joining will not be perceptible. It is said that by
this process small pieces of amber, amber-dust, &c., can be made into
blocks.
In imitating amber, the best pieces of copal are picked out, put into
an air-tight vessel, and dissolved in petroleum, sulphuric ether, or
benzole. After being dried in blocks this is submitted to a great
pressure. As it dries the pressure is increased.
It occurred to me many years ago that the proper way to unite copal to
a tough body like amber would be to use a tough or flexible varnish
as a binding medium. I find by the work of LEHNER on Imitations that
he has verified this by experiment. What is also important is, that
the process of hardening by pressure is by this means very much
facilitated. I should judge, by all chemical laws, that a varnish
infused with glycerine in combination with copal, kauri, or amber-dust
would, even without pressure, form in time a substance quite as hard as
amber, and much less brittle. It is to be desired that some technist
would experiment on a variety of gums in this manner, and thus _fix_
or render permanent their beauty. There is a wide field here to be
worked. The subject of meerschaum and amber is fully treated in a work
entitled _Die Meerschaum- und Bernstein-Fabrikationen_, von G. M.
Raufer; Vienna, A. Hartleben, 2 marks.
I may add that carving amber is a very elegant art, yielding beautiful
results. I have known a young lady, the late Miss Catherine L. Bayard,
who excelled in it. It is effected chiefly with fine files and emery
or glass paper, as, owing to its extremely brittle nature, there
is much risk for any save experts to use cutting tools. Amber is a
very expensive material, but objects made from it are of more than
proportionate value. Those who would practise carving it should begin
with pieces of copal. As I have already explained, small fragments and
the dust of both amber and copal can be melted and combined with clear
turpentine into large masses, which are even tougher than the native
gums.
An inferior, but still very pretty, imitation of amber can be made
by combining almost any gum properly clarified and coloured; as, for
instance, gum-arabic or dextrine with gelatine (best quality white) and
glycerine. If thoroughly well combined and dried, this will wear as
well as amber. Some of the gums of fruit-trees--_e.g._, of the peach
and cherry--are very beautifully coloured and clear, and seem to be
admirably adapted to be hardened by the same process. They occur very
frequently in old books of recipes as adhesives or cements. Perfectly
clear glue or gelatine with glycerine and transparent dyes form an
excellent imitation for beads.
INDIARUBBER AND GUTTA-PERCHA
MENDING INDIARUBBER SHOES AND MAKING GARMENTS WATERPROOF, WITH OTHER
APPLICATIONS
Indiarubber or gutta-percha enters into so many familiar and useful
objects that there are few people who would not like to know how to
repair them when injured.
Like the brittle or non-elastic gums, caoutchouc (with which I include
the nearly allied gutta-percha) is greatly modified by admixture with
certain pulverised substances, which form with it a partly mechanical,
partly chemical, combination. Those who would thoroughly study the
subject in all its relations may consult _Kautschuk_ (_Caoutchouc_)
_und Guttapercha_, von Raimund Hoffer; Wien, 1892, Hartleben.
Caoutchouc is partially soluble in carburetted sulphur, ether, pure
petroleum, or benzole, but gutta-percha is perfectly so. In this state
it may be applied as a varnish or coating for repairs, as it hardens
by exposure to the air. When mixed with sulphur and exposed to a
heat of 110° to 115° centigrade, gutta-percha becomes what is called
“vulcanised,” assuming a very light grey colour, is more elastic, and
retains this elasticity at a much lower grade than before. When the
heat is raised to (maximum) 180° the mass becomes very hard, tough,
and black, or like horn. The conditions of its toughness, elasticity,
and hardness depend upon the amount of sulphur used; as in other
combinations, the harder the material becomes the less elastic it
is--that is, the more brittle.
EBONITE is extremely hardened caoutchouc. It is first treated with
chlorine, washed with sulphate of soda infused in water, and finally
mixed with hardening substances and submitted to severe pressure.
As indiarubber or “gum” shoes are in general use, most people would
consider them the proper objects to begin with. To do this, first make
two separate preparations as follows:
I.
Caoutchouc 10
Chloroform 280
II.
Caoutchouc 10
Resin 4
Turpentine 2
Oil of turpentine 40
No. I. is simply kept for a time in a bottle or tightly closed jar by
itself. No. II. is made by cutting the gum very fine, mixing it with
the resin, then adding the turpentine, and finally dissolving the whole
in the oil of turpentine. Then combine I. and II. To repair the shoe,
take a linen patch, steep it in the mixture, and place it over the
rent. When this is dry apply one or more coats.
It may be observed that this preparation may be used not only for
indiarubber shoes, but many other objects. Applied to the soles of
leather boots, and then heated in, repeating the process a few times,
they become perfectly waterproof. This is better when the shoemaker
makes a coating of it between the two soles. I have tested this often.
The inner sole may be made by simply dissolving the indiarubber in
benzole or ether. A solution for ordinary repairing can be made by
simply steeping the indiarubber in benzine.
Rents or holes in ordinary leather shoes or other objects can be very
well repaired in this way. A piece of leather can in this case be
substituted for the linen rag. Boots or shoes which will be very much
exposed to wet should be warmed and then soaked or permeated with a
solution of indiarubber. Preparations for the purpose can be bought of
all dealers in gum and gutta-percha.
Cloth is generally waterproofed by steeping it in a slight solution of
caoutchouc.
Another recipe (LEHNER) is as follows:--
Caoutchouc 150
Tallow 10
Slacked lime 10
This is used to cork or close bottles. To render it more resistant,
substitute pipeclay for the lime. Or if in place of either we use red
oxide of lead, it will form in time an extremely hard and perfectly
waterproof cement of great value.
A STRONG INDIARUBBER CEMENT:--
Caoutchouc, about 90
Pulverised sulphur 10
Or from 6 to 12 of the latter.
This is specially commended as useful to close tins containing fruits,
&c. It is simply vulcanised indiarubber.
MARINE GLUE is a very valuable and generally useful cement. It is
so called because, being perfectly waterproof, it is used for many
purposes in ships. It is applicable not only to repairing indiarubber
or gutta-percha garments, but also to objects of metal, wood, glass,
stone, paper, or cloth; as, for instance, umbrellas, on which, when
torn, a patch or strip of silk or muslin may be gummed, which will last
as long as the rest. It is also good for waterproofing shoes. It is
sold by dealers in ships’ stores, chemists, and others. “It is a good
thing to have in the country.”
HARD MARINE GLUE:--
Caoutchouc 10
Rectified petroleum 120
Asphalt 20
To prepare this, the caoutchouc should be hung in a linen bag in a
cask with a very large bung, or in a large jar, so that the bag shall
be only half immersed. This is kept in a warm place for from ten to
fourteen days, till the solution is effected. Then the asphaltum
may be melted in an iron kettle. Let the rubber solution slowly run
into the kettle over a gentle heat, and stir in the one to the other
till the mass is thoroughly preserved are put in the bag; the edge
is then turned incorporated. When this is effected pour the mixture
into moulds which have been oiled to prevent adhesion. The result is
dark brown or black thin cakes, which are broken with difficulty. The
excellence of this cement is somewhat counteracted by the difficulty
or care which must be observed in using it. To do this, put the vessel
in which it is to be melted in another or a _balneum mariæ_, as for
glue, filled with boiling water. When fluid take the kettle from the
fire and subject it directly to heat till it attains a temperature of
150° centigrade. When it is possible, heat the object to be glued to
100°. The thinner the coat and the hotter the surface the better will
it adhere, unless the objects be such as hard boards. In all cases as
strong a pressure as possible should be employed to bring the two parts
together, which should be continued till the glue has dried. Boxes
which are cemented together by means of marine glue and are also nailed
are of extraordinary strength, and may be thus made air-tight and
waterproof. Those who intend to send articles which can be affected by
sea-air, such as silks and tea, which change their colour and quality
even when packed in the tightest ordinary cases, should employ boxes
well secured with good marine glue. It is also invaluable to secure
clothing against moths, for if anything be very thoroughly dusted and
there are no moths in it, none can get in if it be enclosed in a box
rendered air-tight.
_Apropos_ of which I would say that in America moths, which are far
more of a pest than in Europe, are effectively excluded by means of
bags of strong paper, well tarpaulined or tarred. The objects to be
over and warmed, so that it seals itself up. Strong paper bags are
better than any trunks to exclude moths, but they must always be well
gummed up. Tobacco is no protection at all against these insects. I
have even had an old woollen Turkish tobacco-bag which had been in use
ten years, and which was partly full of tobacco, almost devoured by
moths, which must have eaten no small quantity of tobacco in so doing.
Nor is camphor or any other scent half as effective as hermetic closing
in some substance which insects will not eat.
LEHNER gives a suggestion regarding the rendering walls air-tight which
is of such remarkable practical utility that it ought to be enforced by
health laws in every house. Whenever walls have any tendency to absorb
dampness--and all have it in damp weather, especially in underground
rooms--it is _far_ more dangerous than is generally supposed to put
paper on them. This is so much the case that where workmen, from
carelessness, paste one coat of paper over another on a damp wall,
the mass in time gives out a very poisonous exhalation, so that an
instance is recorded in which several people died, one after the other,
in consequence of sleeping in such a room. To prevent this take the
following waterproof cement:--
Caoutchouc 10
Washed chalk 10
Oil of turpentine 20
Bisulphide of carbon 10
Resin (colophonium) 5
Asphalt 5
These are combined in a large flask, kept in a moderately warm place,
and often shaken till well incorporated. The wall to be covered should
be brushed and wiped, and in some cases heated, until extremely dry.
Then, using the cement, apply the paper in the ordinary way. It will
stick with great tenacity, this being a very tight and strong glue.
All wall-paper whatever is more or less productive of malaria in damp
weather, as is the smell of a _damp_ library, or one where the scent
of old paper is rankly and offensively perceptible. Therefore every
precaution should be taken to render it innocuous.
Even if no paper be applied, this cement is very valuable when simply
used to coat the interior or exterior of damp walls. It can, of course,
be used to repair many articles of indiarubber, and to mend shoes, tan
garments, &c. _Apropos_ of which latter I may here remark that all
persons who intend to rough it in the bush as colonists, or go into
any region where mending or getting mended is difficult--as I myself
have many a time experienced--would do well to carry a tight tin box of
waterproof glue, with which torn shoes, and very often torn clothes,
can be promptly repaired. In fact, with the aid of a little rough
stitching, or even without it, garments of leather, muslin, and even
of cloth can be made to hold together with certain cements, which will
literally bind anything.
It is well worth while for those who propose to live in the wilderness,
wherever it may be, to know how to prepare or make indiarubber
garments. The recipe is very easily made:--
Gutta-percha 10
Benzine 100
Linseed-oil varnish 100
The gutta-percha is dissolved in the benzine; the solution, when clear,
is poured into a bottle already containing the varnish, and all is
then thoroughly shaken. This mixture, when spread on woven fabrics of
any kind, renders them completely waterproof. The garments can then
be cut out and “sewed;” that is, bound together with the same cement.
According to LEHNER, this cement can be used for making the soles of
shoes, and is marvellously elastic. All travellers, and assuredly all
housekeepers, should have this cement among their possessions.
It may also happen to a traveller to find himself with an aching
hollow tooth in a region where no dentist is accessible. Should he
have with him some gutta-percha (bleached is best for this purpose) he
may combine it with very finely pulverised glass. (To _levigate_ or
powder anything as fine as flour, it must be pounded in a mortar, or on
metal or hard stone _under water_.) Then warm and thoroughly mix the
gutta-percha and glass. Make it into little pencils, which, when they
are to be used, must be dipped in hot water. This cement may be also
used for a great variety of other purposes.
A very admirable cement, which should be found in every stable and
known to every one who owns a horse, is made as follows:--
Hartshorn and resin ammoniacum (_Ammoniakharz_) 10
Purified gutta-percha 20-25
Heat the gutta-percha to 90°-100° centigrade, and thoroughly
incorporate it with the powdered resin. The chief use of this admirable
composition is to fill up cracks or splits in horses’ hoofs. It may
also be used for plaster on occasion. To apply it to hoofs, warm it and
spread it in with a warmed knife. It sets so hard that it will hold
nails.