726 
CASTING A HORSE. 
surrounded with an edging. But, if it be a 
statue, it cannot be withdrawn without breaking 
the mould; and, on this account, it becomes ne- 
cessary to divide the mould into such a number 
of pieces as will separate perfectly from the ori- 
ginal, These are taken off from the statue, and, 
when afterwards replaced, or put together with- 
out the statue, they constitute a perfect mould. 
This mould, its parts having been oiled, to pre- 
vent adhesion, is made to receive a quantity of 
plaster, by pouring it in at a small orifice. The 
mould is then turned in every direction, in order 
that the plaster may fill every part of the surface; 
and, when a sufficient quantity is poured in to 
produce the strength required in the caste, the 
remainder is often left hollow, for the sake of 
lightness, and economy of the material. When 
the cast is dry, it is extricated by separating the 
pieces of the mould, and finished by removing 
the seams and blemishes with the proper tools. 
| If the form or position require it, the limbs are 
| cast separately, and afterwards cemented on. 
Moulds and busts are obtained in a similar man- 
_ ner from living faces, by covering them with new 
_ plaster, and removing it in pieces, as soon as it 
_ becomes hard. 
It is necessary that the skin of 
_ the face should be oiled; and, during the opera- 
he 
_ through tubes inserted in the nostrils. 
_ could not be removed without violence. 
small and delicate impressions in relief, melted 
| sulphur is sometimes used ; also a strong solution 
| of isinglass in proof spirit. 
tion, the eyes are closed, and the person breathes 
Elastic 
moulds have been formed by pouring upon the 
_ figure to be copied a strong solution of glue. 
_ This hardens upon cooling, and takes a fine im- 
pression. It is then cut into suitable pieces, and 
| removed. The advantage of the elastic mould 
is, that it separates more easily from irregular 
surfaces, or those with uneven projections and 
under - cuttings, from which a common mould 
For 
Plaster casts are 
varnished by a mixture of soap and white wax 
in boiling water. A quarter of an ounce of soap 
is dissolved in a pint of water, and an equal 
quantity of wax afterwards incorporated. The 
cast is dipped in this liquid, and, after drying 
a week, is polished by rubbing with soft linen. 
The surface produced in this manner approaches 
to the polish of marble. When plaster casts are 
to be exposed to the weather, their durability is 
greatly increased by saturating them with lin- 
seed oil, with which wax or rosin may be com- 
bined. When intended to resemble bronze, a 
soap is used, made of linseed oil and soda, col- 
oured by the sulphates of copper and iron. Walls 
and ceilings are rendered water-proof in the same 
way. 
CASTING A FCITUS. See Azorrron. 
CASTING A HORSE. The forcing of a horse 
to the ground, in order to subject him to a sur- 
gical operation. It is attended with numerous 
and important risks; and on account of these, it 
| has been wholly discontinued by some practition- 
CASTOR-OIL. 
ers, and ought not, in any case, to be practised 
unless when the restraints of the twitch and the 
side-line are insufficient. The best means for 
casting are the patent hobbles of Mr. Bracy 
Clark; as improved by Mr. Budd; and when these 
are cautiously and skilfully employed, no danger 
whatever may be incurred. A capacious space 
should be selected, and should be thickly littered 
with straw; the hobbles should be attached in 
an order beginning with the forefoot of the op- 
posite side to that on which the animal is to be 
thrown; the legs ought to be drawn as closely 
together as possible, but with such slowness and 
caution as not to alarm the animal; the head 
should be held by a strong snaffle bridle; the 
hinder part should be superintended by an as- 
sistant ready to direct the fall; and then, if all 
the assistants act in concert, they may, by one 
quick and dexterous drawing of the rope, so 
softly capsize the animal as neither to give him 
the slightest shock, nor afford him power to hurt 
himself by struggling. The instant he is thrown, 
the rope must be fastened ; and during the whole 
time of his being down, his head must be held 
fast. Care must be used, however, that he fall 
and lie in such a posture as to have perfect free- 
dom of respiration. 
CASTOR-OIL. The Palma-christi or castor-oil 
plant— Ricinus communis—is a native both of the 
Kast and West Indies, and has a stem from 5 to 15 
or 16 feet in height, and large, bluish-green leaves, 
divided into 7 lobes, serrated and pointed, the 
foot-stalks long, and inserted into the disk. The 
flowers are produced in a terminating spike, and 
the seed-vessels are covered with spines, and con- | 
tain three flattish, oblong seeds. Itis to the seeds | 
of this plant that we are indebted for the drug | 
It is now often prepared by | 
pressing the seeds in the same way as is prac- | 
The oil thus obtained | 
is called cold expressed or cold drawn. But the | 
called castor-oil. 
tised with oil of almonds. 
mode chiefly adopted in the West Indies is first 
to strip the seeds of their husks or pods, and then 
to bruise them in mortars. 
oil which they contain rises to the surface. This 
is carefully skimmed off, strained, to free it from 
any accidental impurities, and bottled for use. 
The oil which is obtained by boiling is considered 
more mild than that procured by pressure, but it 
sooner becomes rancid. The mildest and finest 
Jamaica castor-oil is very limpid, nearly colour- 
less, and has scarcely more smell or taste than 
good olive-oil. Many people, however, have so 
great an aversion to castor-oil, even in its purest 
state, that they do not take it without great re- 
luctance. The uses of castor-oil in medicine are 
well-known. 
amount to a pint or even a pint and a-half; and, 
besides being expensive, is,of uncertain and some- 
times dangerous operation. In most other do- 
mestic animals, however, as well as in man, it 
acts as a mild purgative. 
Afterwards they are | 
tied in linen bags, and boiled in water until the | 
A dose of it to a horse requires to 
