_Rectified Sulphuric Æther._
QUALITIES. A colourless liquid of specific gravity 739°. _Odour_,
pungent and fragrant; it is highly volatile, and when perfectly free
from alcohol it boils at 98°; it is extremely inflammable, a
circumstance which should be remembered when it is poured from one
vessel to another by candle light. CHEMICAL COMPOSITION. When pure it
consists of oxygen, hydrogen, and carbon; the rectified æther however
still contains some water and alcohol, for Lovitz obtained an æther of
632. SOLUBILITY. One part requires for its solution ten of water; with
alcohol and ammonia it unites in every proportion. SOLVENT POWERS. It is
one of the most powerful solvents known in vegetable chemistry, as it
dissolves balsams, resins, gum-resins, wax, camphor, extractive, &c.; it
takes up about a twentieth of its weight of sulphur, but it exerts no
solvent power upon the fixed alkalies. FORMS OF EXHIBITION. In any
liquid vehicle, if in decoctions or infusions, they should be previously
cooled. _See Formulæ 20, 22, 23_. MEDICAL USES. It is highly valuable as
a diffusible stimulant, narcotic, and antispasmodic. DOSE, fʒss to fʒij,
which, in order to produce the full effect of the remedy, must be
repeated at short intervals. Æther, independent of such virtues, has
another valuable property consequent upon its rapid evaporation, that of
producing cold and dryness; it is therefore, when externally applied and
allowed to evaporate, a most powerful refrigerant, and has proved
valuable in scalds or burns, in facilitating the reduction of
strangulated hernia, and in diminishing excessive circulation in the
brain; if however it be so confined, that its rapid evaporation is
prevented, a very opposite effect is produced, and it proves stimulant,
rubefacient, and even vesicatory. With regard to the other property
incidental to it, that of producing dryness, I am not aware that it has
hitherto been applied to any pharmaceutical purpose; the fact may be
satisfactorily shewn by a very simple experiment,—by rincing a phial
with æther, to the interior of which drops of water obstinately adhere,
when by exposing it to a current of air, it will be completely dry in a
few minutes. It may be noticed in this place that a mixture of sulphuric
and muriatic æthers evaporates instantaneously, and produces a degree of
cold considerably below 0 of Fahrenheit. OFFICINAL PREPARATIONS.
_Spiritus Æther: Sulph:_ L. _Spir: Æth: Sulph: comp:_ L. _Spir: Æth:
Aromat:_ L. ADULTERATIONS and IMPURITIES. Its specific gravity affords
the best indication of its purity; _Sulphuric Acid_ may be detected by a
precipitation on the addition of a solution of baryta, and by its
reddening the colour of litmus; _Alcohol_, by its forming with
phosphorus a milky instead of a limpid solution. M. Gay Lussac has
observed that when kept for a considerable time without disturbance, it
undergoes spontaneous decomposition, and that acetic acid, perhaps some
alcohol, and a particular oil, are produced from it.