_Obs._ This is a species of papier-maché. It is used to make architectural
ornaments, busts, statues, columns, &c. It is very light, and receives a
good polish, but will not stand the weather unless it is well varnished or
painted.
=Cement, Arme'nian.= _Syn._ DIAMOND CEMENT, PERSIAN C., TURKISH C.,
JEWELLERS' C. The jewellers of Turkey, who are mostly Armenians, have a
singular method of ornamenting watch-cases, &c., with diamonds and other
precious stones, by simply gluing or cementing them on. The stone is set
in silver or gold, and the lower part of the metal made flat, or to
correspond with the part to which it is to be fixed; it is then gently
warmed, and the glue is applied, which is so very strong that the parts
thus cemented never separate. This glue will strongly unite pieces of
glass and china, and even polished steel, and may be applied to a variety
of useful purposes.
_Prep._ 1. (Original Armenian formula; Eton.) Dissolve five or six bits of
gum mastic, each the size of a large pea, in as much rectified spirit of
wine as will suffice to render it liquid; and, in another vessel, dissolve
as much isinglass, previously a little softened in water (though none of
the water must be used), in French brandy or good rum, as will make a
two-ounce phial of very strong glue, adding two small bits of gum galbanum
or ammoniacum, which must be rubbed or ground till they are dissolved.
Then mix the whole with a sufficient heat. Keep the glue in a phial
closely stopped, and when it is to be used set the phial in boiling water.
2. (Keller's ARMENIAN CEMENT.) Soak isinglass, 1/2 oz., in water, 4 oz.,
for 24 hours; evaporate in a water bath to 2 oz.; add rectified spirit, 2
oz., and strain through linen; mix this, whilst warm, with a solution
formed by dissolving gum mastic (best), 1/4 oz., in rectified spirit, 2
oz.; add of powdered gum ammoniac 1 dr., and triturate together until
perfectly incorporated, avoiding loss of the spirit by evaporation as much
as possible.
3. (Ure's DIAMOND CEMENT.) Isinglass, 1 oz.; distilled water, 6 oz.; boil
to 3 oz., and add rectified spirit, 1-1/2 oz.; boil for a minute or two,
strain, and add, while hot, first a milky emulsion of ammoniac, 1/2 oz.,
and then tincture of mastic, 5 dr.
4. Isinglass soaked in water and dissolved in spirit, 2 oz. (thick);
dissolve in this 10 gr. of very pale gum ammoniac (in tears), by rubbing
them together; then add 6 large tears of gum mastic, dissolved in the
least possible quantity of rectified spirit.
5. Isinglass dissolved in proof spirit (as _above_), 3 oz.; bottoms of
mastic varnish (thick, but clear), 1-1/2 oz.; mix well.
_Obs._ When carefully made, this cement resists moisture and dries
colourless. As usually met with, it is not only of very bad quality, but
sold at exorbitant prices. "Some persons have sold a composition under the
name of Armenian cement in England; but this composition is badly made; it
is much too thin, and the quantity of mastic is much too small." (Eton.)
Methylated spirit may be used instead of the pure spirit in the above
preparations. Mastic and mastic varnish are also used by jewellers as
cements.
=Cement, Beale's.= Chalk, 60 parts; lime and salt, of each 20 parts;
Barnsey sand, 10 parts; iron filings or dust, and blue or red clay, of
each 5 parts; grind together and calcine. Patented as a fire-proof cement.
=Cement, Boil'er.= _Prep._ Dried clay in powder, 6 lbs.; iron filings, 1
lb. Make into a paste with boiled linseed oil. Used to stop cracks and
leaks in iron boilers, stoves, &c. See CEMENT, IRON, STEAM-BOILER C.
=Cement, Bot'any Bay.= Yellow gum (Botany Bay gum) and brickdust, equal
parts, melted together. Used to cement coarse earthenware, &c.
=Cement, Bot'tle.= _Prep._ 1. Resin, 1 lb.; tallow or suet, 1/4 lb.; melt
together, and stir in the colouring matter.