Page 251 - My FlipBook

ETHER. — 249

.^iTHER-ETHER.
iETHER SULPHURICUS—SULPHURIC ETHER.
Formula.—C^HjyO, or (02^15)20. Sp. gr.—Of pure ether,
0.713; of stronger ether, 0.728; of ordinary officinal ether,
0.750.
Derivation.—Sulphuric Ether is obtained by the distillation of
alcohol and sulphuric acid, and is rectified by re-distillation with
solution of potassa. The form of sulphuric ether employed for
inhalation is still further purified by agitation with water, and it
is freed from this and from an excess of alcohol and deleterious
acid substances by the action of chloride of lime and freshly
calcined lime, when it is known as stronger ether /Ether
Fortior. Pure ether has a Sp. gr., 0.713, and is practically free
from alcohol and water. Sulphuric ether is a colorless, limpid,
volatile and inflammable fluid, with a sweet, penetrating odor
and a hot, pungent taste ; on account of its great volatility, it
should be kept securely in ground-glass-stoppered bottles. It
should never be held near a fire or light. It usually reddens
litmus paper slightly ; when it does so strongly, the ether is im-
pure. The impurities, besides acids and fixed substances, are
heavy oil of wine, an excess of alcohol and water. Acids be-
ing detected by litmus paper, may be removed by agitation with
fixed substances may be removed by evaporating the
potassa ;
ether. Some alcohol is always found in ether, and it is only
when it is present in too great a quantity that the density of the
ether is rendered too high. The quantity of alcohol any prep-
aration of ether may contain, can be determined by agitating it
in a minim measure with half its volume of a concentrated
solution of chloride of calcium. This will remove the alcohol,
and the reduction of the volume of ether when it rises to the
surface will indicate the amount of alcohol which has been pres-
ent. Heavy oil of wine can be detected by the ether becoming
milky when mixed with water. Ether boils at 95° P\, and a
cold of 166° below zero will not freeze it. When kept too
long it undergoes decomposition, and is converted in part into
acetic acid.
It evaporates so readily and completely in the air as to cause a