especially the handles, are nearly all cast out of tin and antimony,
and in brass molds. The metal used is brittle, and requires
strengthening at the weak portions, and this is mostly done with wood
filling or with iron rods, which are secured in the molds before the
metal is poured in.
Aluminum castings, which one has procured at the foundries, are usually
alloyed with zinc. This has a close affinity with aluminum, and alloys
readily; but this mixture is a detriment and causes much trouble
afterwards. While this alloy assists the molder to produce his castings
easily, on the other hand it will not polish well and will corrode in a
short time. Those difficulties may be avoided if pure aluminum is used.
Plaster of Paris molds are the easiest made for pieces where only a few
castings are wanted. The only difficulty is that it requires a few days
to dry the plaster thoroughly, and that is absolutely necessary to use
them successfully. Not only can the softer metals be run into plaster
molds, but gold and silver can be run into them. A plaster mold should
be well smoked over a gaslight, or until well covered with a layer of
soot, and the metal should be poured in as cool a state as it will run.
«To Prevent the Adhesion of Modeling Sand to Castings.»—Use a mixture
of finely ground coke and graphite. Although the former material is
highly porous, possessing this quality even as a fine powder, and
the fine pulverization is a difficult operation, still the invention
attains its purpose of producing an absolutely smooth surface. This is
accomplished by mixing both substances intimately and adding melted
rosin, whereupon the whole mass is exposed to heat, so that the rosin
decomposes, its carbon residue filling up the finest pores of the
coke. The rosin, in melting, carries the fine graphite particles along
into the pores. After cooling the mass is first ground in edge mills,
then again in a suitable manner and sifted. Surprising results are
obtained with this material. It is advisable to take proportionately
little graphite, as the different co-efficients of expansion of the
two substances may easily exercise a disturbing action. One-fifth of
graphite, in respect to the whole mass, gives the best results, but it
is advisable to add plenty of rosin. The liquid mixture must, before
burning, possess the consistency of mortar.
«Sand Holes in Cast-Brass Work.»—Cast-brass work, when it presents
numerous and deep sand holes, should be well dipped into the dipping
acid before being polished, in order thoroughly to clean these
objectionable cavities; and the polishing should be pushed to an extent
sufficient to obliterate the smaller sand holes, if possible, as this
class of work looks very unsightly, when plated and finished, if
pitted all over with minute hollows. The larger holes cannot, without
considerable labor, be obliterated; indeed, it not infrequently happens
that in endeavoring to work out such cavities they become enlarged, as
they often extend deep into the body of the metal. An experienced hand
knows how far he dare go in polishing work of this awkward character.
«Black Wash for Casting Molds.»—Gumlac, 1 part; wood spirit, 2 parts;
lampblack, in sufficient quantity to color.
«How to Make a Plaster Cast of a Coin or Medal.»—The most exact
observance of any written or printed directions is no guarantee of
success. Practice alone can give expertness in this work. {151} The
composition of the mold is of the most varied, but the materials most
generally used are plaster of Paris and brick dust, in the proportion
of 2 parts of the first to 1 of the second, stirred in water, with the
addition of a little sal ammoniac. The best quality of plaster for
this purpose is the so-called alabaster, and the brick dust should
be as finely powdered as possible. The addition of clay, dried and
very finely powdered, is recommended. With very delicate objects the
proportion of plaster may be slightly increased. The dry material
should be thoroughly mixed before the addition of water.
As the geometrically exact contour of the coin or medal is often the
cause of breaking of the edges, the operator sometimes uses wax to
make the edges appear half round and it also allows the casting to be
more easily removed from the second half of the mold. Each half of the
mold should be about the thickness of the finger. The keys, so called,
of every plaster casting must not be forgotten. In the first casting
some little half-spherical cavities should be scooped out, which will
appear in the second half-round knobs, and which, by engaging with the
depressions, will ensure exactness in the finished mold.
After the plaster has set, cut a canal for the flow of the molten
casting material, then dry the mold thoroughly in an oven strongly
heated. The halves are now ready to be bound together with a light
wire. When bound heat the mold gradually and slowly and let the mouth
of the canal remain underneath while the heating is in progress,
in order to prevent the possible entry of dirt or foreign matter.
The heating should be continued as long as there is a suspicion of
remaining moisture. When finally assured of this fact, take out the
mold, open it, and blow it out, to make sure of absolute cleanness.
Close and bind again and place on a hearth of fine, hot sand. The mold
should still be glowing when the casting is made. The ladle should
contain plenty of metal, so as to hold the heat while the casting is
being made. The presence of a little zinc in the metal ensures a sharp
casting. Finally, to ensure success, it is always better to provide two
molds in case of accident. Even the most practiced metal molders take
this precaution, especially when casting delicate objects.
«How to Make Castings of Insects.»—The object—a dead beetle, for
example—is first arranged in a natural position, and the feet are
connected with an oval rim of wax. It is then fixed in the center of
a paper or wooden box by means of pieces of fine wire, so that it is
perfectly free, and thicker wires are run from the sides of the box
to the object, which subsequently serve to form air channels in the
mold by their removal. A wooden stick, tapering toward the bottom, is
placed upon the back of the insect to produce a runner for casting.
The box is then filled up with a paste with 3 parts of plaster of
Paris and 1 of brick dust, made up with a solution of alum and sal
ammoniac. It is also well first to brush the object with this paste
to prevent the formation of air bubbles. After the mold thus formed
has set, the object is removed from the interior by first reducing it
to ashes. It is, therefore, allowed to dry, very slowly at first, by
leaving in the shade at a normal temperature (as in India this is much
higher than in our zone, it will be necessary to place the mold in a
moderately warm place), and afterwards heating gradually to a red heat.
This incinerates the object, and melts the waxen base upon which it
is placed. The latter escapes, and is burned as it does so, and the
object, reduced to fine ashes, is removed through the wire holes as
suggested above. The casting is then made in the ordinary manner.
«Casting of Soft Metal Castings.»—I.—It is often difficult to form flat
back or half castings out of the softer metals so that they will run
full, owing mostly to the thin edges and frail connections. Instead of
using solid metal backs for the molds it is better to use cardboard,
or heavy, smooth paper, fastened to a wooden board fitted to the back
of the other half of the mold. By this means very thin castings may be
produced that would be more difficult with a solid metal back.
II.—To obtain a full casting in brass molds for soft metal two
important points should be observed. One is to have the deep recesses
vented so the air will escape, and the other is to have the mold
properly blued. The bluing is best done by dipping the mold in
sulphuric acid, then placing it on a gas stove until the mold is a dark
color. Unless this bluing is done it will be impossible to obtain a
sharp casting.
«Drosses.»—All the softer grades of metal throw off considerable dross,
which is usually skimmed off; especially with tin and its composition.
Should much of this gather on the top of the molten {152} metal, the
drosses should all be saved, and melted down when there is enough for
a kettle full. Dross may be remelted five or six times before all the
good metal is out.
«Fuel.»—Where a good soft coal can be had at a low price, as in the
middle West, this is perhaps the cheapest and easiest fuel to use;
and, besides, it has some advantages over gas, which is so much used
in the East. A soft-coal fire can be regulated to keep the metal at
an even temperature, and it is especially handy to keep the metal in
a molten state during the noon hour. This refers particularly to the
gas furnaces that are operated from the power plant in the shop; when
this power shuts down during the noon hour the metal becomes chilled,
and much time is lost by the remelting after one o’clock, or at the
beginning in the morning.
«Molds.»—I.—Brass molds for the casting of soft metal ornaments out
of britannia, pewter, spelter, etc., should be made out of brass that
contains enough zinc to produce a light-colored brass. While this hard
brass is more difficult for the mold maker to cut, the superiority
over the dark red copper-colored brass is that it will stand more heat
and rougher usage and thereby offset the extra labor of cutting the
hard brass. The mold should be heavy enough to retain sufficient heat
while the worker is removing a finished casting from the mold so that
the next pouring will come full. If the mold is too light it cools more
quickly, and consequently the castings are chilled and will not run
full. Where the molds are heavy enough they will admit the use of a
swab and water after each pouring. This chills the casting so that it
can be removed easily with the plyers.
II.—Molds for the use of soft metal castings may be made out of soft
metal. This is done with articles that are not numerous, or not often
used; and may be looked upon as temporary. The molds are made in
part the same as when of brass, and out of tin that contains as much
hardening as possible. The hardening consists of antimony and copper.
This metal mold must be painted over several times with Spanish red,
which tends to prevent the metal from melting. The metal must not be
used too hot, otherwise it will melt the mold. By a little careful
manipulation many pieces can be cast with these molds.
III.—New iron or brass molds must be blued before they can be used for
casting purposes. This is done by placing the mold face downward on a
charcoal fire, or by swabbing with sulphuric acid, then placing over a
gas flame or charcoal fire until the mold is perfectly oxidized.
IV.—A good substantial mold for small castings of soft metal is made of
brass. The expense of making the cast mold is considerable, however,
and, on that account, some manufacturers are making their molds by
electro-deposition. This produces a much cheaper mold, which can be
made very quickly. The electro-deposited mold, however, is very frail
in comparison with a brass casting, and consequently must be handled
very carefully to keep its shape. The electro-deposited ones are made
out of copper, and the backs filled in with a softer metal. The handles
are secured with screws.
«Plaster Molds.»—Castings of any metal can be done in a plaster mold,
provided the mold has dried, at a moderate heat, for several days.
Smoke the mold well with a brand of rosin to insure a full cast. Where
there are only one or two ornaments or figures to cast, it may be done
in a mold made out of dental plaster. After the mold is made and set
enough so that it can be taken apart, it should be placed in a warm
place and left to dry for a day or two. When ready to use the inside
should be well smoked over a gaslight; the mold should be well warmed
and the metal must not be too hot. Very good castings may be obtained
this way; the only objection being the length of time needed for a
thorough drying of the mold.
«Temperature of Metal.»—Metals for casting purposes should not be
overheated. If any of the softer metals show blue colors after cooling
it is an indication that the metal is too hot. The metal should be
heated enough so that it can be poured, and the finished casting have
a bright, clean appearance. The mold may be very warm, then the metal
need not be so hot for bright, clean castings. Some of the metals will
not stand reheating too often, as this will cause them to run sluggish.
Britannia metal should not be skimmed or stirred too much, otherwise
there will be too much loss in the dross.
CASTING IN WAX: See Modeling.
CASTINGS, TO SOFTEN IRON: See Iron. {153}
«CASTOR OIL:»
«Purifying Rancid Castor Oil.»—To clean rancid castor oil mix 100
parts of the oil at 95° F. with a mixture of 1 part of alcohol (96 per
cent) and 1 part of sulphuric acid. Allow to settle for 24 hours and
then carefully decant from the precipitate. Now wash with warm water,
boiling for 1/2 hour; allow to settle for 24 hours in well closed
vessels, after which time the purified oil may be taken off.
«How to Pour Out Castor Oil.»—Any one who has tried to pour castor
oil from a square, 5-gallon can, when it is full, knows how difficult
it is to avoid a mess. This, however, may be avoided by having a hole
punched in the cap which screws onto the can, and a tube, 2 inches
long and 3/4 of an inch in diameter, soldered on. With a wire nail
a hole is punched in the top of the can between the screw cap and the
edge of the can. This will admit air while pouring. Resting the can
on a table, with the screw-cap tube to the rear, the can is carefully
tilted forward with one hand and the shop bottle held in the other.
In this way the bottle may be filled without spilling any of the oil
and that, too, without a funnel. It is preferable to rest the can on
a table when pouring from a 1- or 2-gallon square varnish can, when
filling shop bottles. With the opening to the rear, the can is likewise
tilted forward slowly so as to allow the surface of the liquid to
become “at rest.” Even mobile liquids, such as spirits of turpentine,
may be poured into shop bottles without a funnel. Of course, the main
thing is that the can be lowered slowly, otherwise the first portion
may spurt out over the bottle. With 5-gallon round cans it is possible
to fill shop bottles in the same manner by resting the can on a box or
counter. When a funnel is used for non-greasy liquids, the funnel may
be slightly raised with the thumb and little finger from the neck of
the bottle, while holding the bottle by the neck between the middle and
ring fingers, to allow egress of air.
«Tasteless Castor Oil.»—
I.—Pure castor oil 1 pint
Cologne spirit 3 fluidounces
Oil of wintergreen 40 minims
Oil of sassafras 20 minims
Oil of anise 15 minims
Saccharine 5 grains
Hot water, a sufficient quantity.
Place the castor oil in a gallon bottle. Add a pint of hot water and
shake vigorously for about 15 minutes. Then pour the mixture into a
vessel with a stopcock at its base, and allow the mixture to stand for
12 hours. Draw off the oil, excepting the last portion, which must be
rejected. Dissolve the essential oils and saccharine in the cologne
spirit and add to the washed castor oil.
II.—First prepare an aromatic solution of saccharine as follows:
Refined saccharine 25 parts
Vanillin 5 parts
Absolute alcohol 950 parts
Oil of cinnamon 20 parts
Dissolve the saccharine and vanillin in the alcohol, then add the
cinnamon oil, agitate well and filter. Of this liquid add 20 parts
to 980 parts of castor oil and mix by agitation. Castor oil, like
cod-liver oil, may be rendered nearly tasteless, it is claimed, by
treating it as follows: Into a matrass of suitable size put 50 parts
of freshly roasted coffee, ground as fine as possible, and 25 parts of
purified and freshly prepared bone or ivory black. Pour over the mass
1,000 parts of the oil to be deodorized and rendered tasteless, and
mix. Cork the container tightly, put on a water bath, and raise the
temperature to about 140° F. Keep at this heat from 15 to 20 minutes,
then let cool down, slowly, to 90°, at which temperature let stand for
3 hours. Finally filter, and put up in small, well-stoppered bottles.
III.—Vanillin 3 grains
Garantose 4 grains
Ol. menth. pip. 8 minims
Alcoholis 3 drachms
Ol. ricinus 12 ounces
Ol. olivæ (imported), quantity sufficient 1 pint
M. ft. sol.
Mix vanillin, garantose, ol. menth. pip. with alcohol and add castor
oil and olive oil.
Dose: One drachm to 2 fluidounces.
IV.—The following keeps well:
Castor oil 24 parts
Glycerine 24 parts
Tincture of orange peel 8 parts
Tincture of senega 2 parts
Cinnamon water enough to make 100 parts
Mix and make an emulsion. Dose is 1 tablespoonful.
V.—One part of common cooking molasses to 2 of castor oil is the best
{154} disguise for the taste of the oil that can be used.
VI.—Castor oil 1 1/2 ounces
Powdered acacia 2 drachms
Sugar 2 drachms
Peppermint water 4 ounces
Triturate the sugar and acacia, adding the oil gradually; when these
have been thoroughly incorporated add the peppermint water in small
portions, triturating the mixture until an emulsion is formed.
VII.—This formula for an emulsion is said to yield a fairly
satisfactory product:
Castor oil 500 c.c.
Mucilage of acacia 125 c.c.
Spirit of gaultheria 10 grams
Sugar 1 gram
Sodium bicarbonate 1 gram
VIII.—Castor oil 1 ounce
Compound tincture of cardamom 4 drachms
Oil of wintergreen 3 drops
Powdered acacia 3 drachms
Sugar 2 drachms
Cinnamon water enough to make 4 ounces.
IX.—Castor oil 12 ounces
Vanillin 3 grains
Saccharine 4 grains
Oil of peppermint 8 minims
Alcohol 3 drachms
Olive oil enough to make 1 pint.
In any case, use only a fresh oil.
«How to Take Castor Oil.»—The disgust for castor oil is due to the
odor, not to the taste. If the patient grips the nostrils firmly before
pouring out the dose, drinks the oil complacently, and then thoroughly
cleanses the mouth, lips, larynx, etc., with water, removing the last
vestige of the oil before removing the fingers, he will not get the
least taste from the oil, which is bland and tasteless. It all depends
upon preventing any oil from entering the nose during the time while
there is any oil present.
«Castor-Oil Chocolate Lozenges.»—
Cacao, free from oil 250 parts
Castor oil 250 parts
Sugar, pulverized 500 parts
Vanillin sugar 5 parts
Mix the chocolate and oil and heat in the water, both under constant
stirring. Have the sugar well dried and add, stirring constantly, to
the molten mass. Continue the heat for 30 minutes, then pour out and
divide into lozenges in the usual way.
CAT DISEASES AND THEIR REMEDIES: See Insecticides and Veterinary
Formulas.
«CATATYPY.»
It is a well-known fact that the reactions of the compounds of silver,
platinum, and chromium in photographic processes are generally
voluntary ones and that the light really acts only as an accelerator,
that is to say the chemical properties of the preparations also change
in the dark, though a longer time is required. When these preparations
are exposed to the light under a negative, the modification of their
chemical properties is accelerated in such a way that, through the
gradations of the tone-values in the negative, the positive print is
formed. Now it has been found that we also have such accelerators in
material substances that can be used in the light, the process being
termed catalysis. It is remarkable that these substances, called
catalyzers, apparently do not take part in the process, but bring about
merely by their presence, decomposition or combination of other bodies
during or upon contact. Hence, catalysis may be defined, in short, as
the act of changing or accelerating the speed of a chemical reaction
by means of agents which appear to remain stable.
Professor Ostwald and Dr. O. Gros, of the Leipsic University, have
given the name of “catatypy” to the new copying process. The use
of light is entirely done away with, except that for the sake of
convenience the manipulations are executed in the light. All that
is necessary is to bring paper and negative into contact, no matter
whether in the light or in the dark. Hence the negative (if necessary
a positive may also be employed) need not even be transparent, for the
ascending and descending action of the tone values in the positive
picture is produced only by the quantity in the varying density of the
silver powder contained in the negative. Hence no photographic (light)
picture, but a catatypic picture (produced by contact) is created, but
the final result is the same.
Catatypy is carried out as follows: Pour dioxide of hydrogen over the
negative, which can be done without any damage to the latter, and lay a
piece of paper on (sized or unsized, rough or smooth, according to the
effect desired); by a contact lasting a few seconds the paper receives
the picture, dioxide of hydrogen being destroyed. From a single
application several prints can be made. The acquired picture—still
{155} invisible—may now in the further course of the process, have
a reducing or oxydizing action. As picture-producing bodies, the
large group of iron salts are above all eminently adapted, but other
substances, such as chromium, manganese, etc., as well as pigments with
glue solutions may also be employed. The development takes place as
follows: When the paper which has been in contact with the negative is
drawn through a solution of ferrous oxide, the protoxide is transformed
into oxide by the peroxide, hence a yellow positive picture, consisting
of iron oxide, results, which can be readily changed into other
compounds, so that the most varying tones of color can be obtained.
With the use of pigments, in conjunction with a glue solution, the
action is as follows: In the places where the picture is, the layer
with the pigments becomes insoluble and all other dye stuffs can be
washed off with water.
The chemical inks and reductions, as well as color pigments, of which
the pictures consist, have been carefully tested and are composed of
such as are known to possess unlimited durability.
After a short contact, simply immerse the picture in the respective
solution, wash out, and a permanent picture is obtained.
CATERPILLAR DESTROYERS: See Insecticides.
«CATGUT:»
«Preparation of Catgut Sutures.»—The catgut is stretched tightly
over a glass plate tanned in 5 per cent watery extract of quebracho,
washed for a short time in water, subjected to the action of a 4 per
cent formalin solution for 24 to 48 hours, washed in running water
for 24 hours, boiled in water for 10 to 15 minutes, and stored in a
mixture of absolute alcohol with 5 per cent glycerine and 4 per cent
carbolic acid. In experiments on dogs, this suture material in aseptic
wounds remained intact for 65 days, and was absorbed after 83 days. In
infected wounds it was absorbed after 32 days.
CATSUP (ADULTERATED): See Foods.
CATTLE DIPS AND APPLICATIONS: See Disinfectants and Insecticides.
CEILING CLEANERS: See Cleaning Preparations and Methods, and also
Household Formulas.
«CELERY COMPOUND.»
Celery (seed ground) 25 parts
Coca leaves (ground) 25 parts
Black haw (ground) 25 parts
Hyoscyamus leaves (ground) 12 1/2 parts
Podophyllum (powdered) 10 parts
Orange peel (ground) 6 parts
Sugar (granulated) 100 parts
Alcohol 150 parts
Water, q. s. ad. 400 parts
Mix the alcohol with 150 parts of water and macerate drugs for 24
hours; pack in percolator and pour on menstruum till 340 parts is
obtained; dissolve sugar in it and strain.
CELLS, SOLUTIONS AND FILLERS FOR BATTERY: See Battery Solutions and
Fillers.
CELLARS, WATERPROOF: See Household Formulas.
CELLOIDIN PAPER: See Paper.
«Celluloid»
«New Celluloid.»—M. Ortmann has ascertained that turpentine produced
by the _Pinus larix_, generally denominated Venice turpentine,
in combination with acetone (dimethyl ketone), yields the best
results; but other turpentines, such as the American from the _Pinus
australis_, the Canada turpentine from the _Pinus balsamea_, the
French turpentine from the _Pinus maritima_, and ketones, such as
the ketone of methyl-ethyl, the ketone of dinaphthyl, the ketone of
methyl-oxynaphthyl, and the ketone of dioxy-naphthyl, may be employed.