S O A 
S O A 
order to ascertain the proportions of its in- 
i»red tents; bnt the result of their experi- 
ments is various, because thev used soap con- 
laining various quantities of water. From the 
experiments of Darcet, Lelievre, and Pel- 
letier, it appears that soap newly made and 
-exposed to sale contains 
60.94 oil 
8.56 a Heal i 
30.50 water 
100.00 
Soap is soluble both in water and in alco- 
hol. Its properties as u detergent are too 
well known to require any description. 
Soap made with tallow and soda has a 
white colour, and is therefore known by the 
name of white soap ; but it is usual for soap- 
makers, in order to lower the price of the 
article, to mix a considerable portion of rosin 
with the tallow ; this mixture forms the com- 
mon yellow or turpentine soap of this coun- 
try. 
Soap of potass, or soft soap. Potass may 
be substituted for soda in making soap, and 
in that case precisely the same process is to 
be followed. It is remarkable, that when 
potass is used, the soap does not assume a 
. solid form; its consistence is never greater 
than that of hog's lard. This is what in 
tais country is called soft soap. Its proper- 
ties as a detergent do not dili’er materially 
from those of hard soap, but it is not nearly 
convenient for use. The alkali employed 
by the antient Crawls and Germans in the 
formation of soap was potass; hence we see 
the reason that it is described by the Ro- 
mans as an unguent. The oil employed for 
making soft soap in this country is whale-oil. 
A little tallow is also added, which, by peculiar 
management, is dispersed through the soap 
in fine white spots. 
Some persons have affirmed that they 
knew a method of making hard soap with 
potass. Their method is this : After forming 
the soap in the manner above described, they 
add to it a large quantity of common salt, 
boil it for some time, and the soap becomes 
solid when cooled in the usual way. That 
this method may be practised with success, 
has been ascertained by Messrs. Darcet, 
Lelievre, and Pelletier ; hut then the hard 
soap thus formed does not contain potass 
but soda ; for when the common salt (muriat 
of soda) is added, the potass of the soap de- 
composes it, and combines with its muriatic 
acid, while at the same time the soda of the 
sdt combines with the oil, and forms hard 
soap; and the muriat of potass formed by this 
double decomposition is dissolved in water, 
and drawn off along with it. 
Chaptal has lately proposed to substitute 
wool in place of oil in the making of soap. 
The ley is formed in the usual manner, and 
jnade boiling hot, and shreds of woollen 
cloth of any kind are gradually thrown into 
it ; they are soon dissolved. New portions 
arc to be added sparingly, and the mixture 
is to be constantly agitated. W hen no more 
cloth can be dissolved, the soap is made. 
This soap is said to- have been tried with suc- 
cess. It might doubtless be substituted for 
soap with advantage in several manufactures, 
provided it can be obtained at a cheaper 
rate titan the soaps at present employed. 
Some time ago a proposal was made to 
substitute the muscles of lish instead of tal- 
low or oil in tiie manufacture of soap; but 
the experiments of Mr. Jamieson have de- 
monstrated that they do not answer the pur- 
pose. 
Soap of ammonia. This soap was first 
particularly attended to by Mr. Berthollet. 
It may be formed by pouring carbonat of 
ammonia on soap of lime. A double de- 
composition takes place, and the soap of 
ammonia swims upon the surface of the liquor 
in (he form of an oil ; or it may be formed 
with still greater ease by pouring a solution 
of muriat of ammonia into common soap 
dissolved in water. 
It has a more pungent taste than common 
soap. Water dissolves a very small quantity 
ot it; but it is easily dissolved in alcohol. 
W hen exposed to the air, it is gradually de- 
composed. The substance called volatile 
linament, which is employed as an external 
application in rheumatisms, colds, & c. may 
be considered as scarcely any thing else than 
this soap. 
All the alkaline soaps agree in the proper- 
ties of solubility in water and alcohol, and in 
being powerful detergents. 
Soaps, earth;/. The earthy soaps differ 
essentially from the alkaline in their proper- 
ties. They are insoluble in water, and inca- 
pable of being employed as detergents. 
They may be formed very readily by mixing 
common soap with a solution of an earthy 
salt ; the alkali of the soap combines with the 
acid of the salt, while the earth and oil unite 
together and form an earthy soap. Hence 
the reason that all waters holding an earthy 
salt are unfit for washing. They decompose 
common soap, and form an earthy soap in- 
soluble in water. These waters are well 
known by the name of hard waters. Hitherto 
the earthy soaps have been examined by Mr. 
Berthollet only. 
Soap of lime. This soap may be formed 
by pouring lime-water into a solution of com- 
mon soap. It is insoluble both in water and 
alcohol. Carbonat of fixed alkali decom- 
poses it by compound affinity. It melts with 
difficulty, and requires a strong heat. 
Soap of barytes and of strontiau resemble 
almost exactly the soap of lime. 
Soap of magnesia may be formed by mix- 
ing together solution of common soap and 
sulphat of magnesia. It is exceedingly white. 
It is unctuous, dries with difficulty, and pre- 
serves its whiteness after desiccation. It is 
insoluble in boiling water. Alcohol and fixed 
oii dissolve it in considerable quantity. Wa- 
ter renders its solution in alcohol milky. A 
moderate heat melts it ; a transparent mass 
is formed, slightly yellow, and very brittle. 
Soap of alumina may be formed by mixing 
together solutions of alum and of common 
soap. It is a flexible soft substance, which 
retains its suppleness and tenacity when dry. 
It is insoluble in alcohol, water, ami oil. 
Heat easily melts it, and reduces it to a beau- 
tiful transparent yellowish, mass. 
Metallic oxides are capable of combining 
with oils by two different processes: 1. By 
mixing together a solution of common soap 
with a metallic salt. 2. By uniting the me- 
tallic oxide with the oil directly, either cold 
>r by the assistance ot heat. "The first o! 
hese combinations is called a metallic soap ; 
.he second a plaster, bee Plaster. 
S 0 c 
Soaps , metallic. These soaps have been , 
examined by Mr. Berthollet ; who has pro- 
posed some of them as paints', and others as 
varnishes ; but it does not appear that any of 
them has been hitherto applied to these pur- I 
poses. 
1. Soap of mercury may be formed bv 
mixing together a solution of common soap 
and of corrosive muriat of mercury. The 
liquor becomes milky, and the soap of mer- 
cury is gradually precipitated. This soap 
is viscid, not easily dried, loses its white co- 
lour when exposed to the air, and acquires 
a slate-colour, which gradually becomes deep- 
er, especially if exposed to the sun or to heat. 
It dissolves very well in oil, but sparingly in 
alcohol. It readily becomes soft andiluid 
when heated. 
2. Soap of zinc may be formed by mixing 
together a solution of sulphat of zinc and of 
soap. It is of a white colour, inclining to 
yellow. It dries speedily, and becomes tri- 
able. 
3. Soap of cobalt, made by mixing nitrat 
ot cobalt and common soap, is of a dull 
leaden colour, and dries with difficulty, 
though its parts are not conducted. 
Mr. Berthollet observed, that towards the 
end of the precipitation there fell down some 
green coagula, much more consistent than 
soap of cobalt. r i hese he supposed to be a 
soap ot nickel, which is generally mixed with 
cobalt. 
4. Soap of tin may be formed by mixing 
common soap with a solution of tin in nitron- 
muriatic acid. It is white. Heat does not 
fuse it like other metallic soaps, but decom- 
poses it. 
5. Soap of iron may be formed by means 
of sulphat of iron. It is of a reddish-brown 
colour, tenacious, and easily fusible. When 
spread upon wool, it sinks in and dries. It 
is easily soluble in oil, especially of turpen- 
tine. Berthollet proposes it as a varnish. 
6. Soap of copper may be formed by means 
of sulphat of copper. It is of a green colour, 
has the feel ot a resin, and becomes dry and 
buttle. Hot alcohol renders its colour deep- 
er, but scarcely dissolves it. Ether dissolves 
it, liquefies it, and renders its colour deeper 
and more beautilul. It is very soluble in 
oils, and gives them a pleasant green colour. 
7. Soap of lead may be formed by means 
of acetite of lead. It is white, tenacious, and 
very adhesive when heated. When fused it 
is transparent, and becomes somewhat yellow 
if the heat is increased. 
8. Soap of silver may be formed by means 
of nitrat of silver. It is at first white, but 
becomes reddish by exposure to the air. 
W hen fused, its surface becomes covered 
with a brilliant iris ; beneath the surface it is 
black. 
9. Soap of gold is formed by means of 
muriat of gold. It is at first white, and of the 
consistence of cream. It gradually assumes 
a dirty purple colour, and adheres to the 
skin. 
10. Soap of manganese is formed of sul- 
phat of manganese. It is at first white, ar4 
then by absorbing oxygen it becomes red. 
SOCAGE, an antient tenure, by which 
lands were held on condition of ploughing the 
lord’s lands, and doing the operations of hus- 
bandry, at their own charges. 
SOC'CLS, in antiquity, a kind of high 
shoe, reaching above the ancle, worn by 
