Ammonia praep. Ph. Lond.

Aqua ammonias purae Ph. Lond.

Alcali volat. caust.Ph.Ed.

Alcali volatile ex fale ammon.vul-gofal ammon. volat.Ph.EA

Some have mixed a quantity of this caustic spirit with the officinal spirits both of sal ammoniac and of hartshorn; which thus become more pungent, so as to bear an addition of a considerable proportion of water without danger of discovery from the taste or smell. This abuse may be detected, by adding to the suspected spirit a quantity of spirit of wine; which, if the volatile spirit is genuine, will precipitate a part of its volatile salt, but has no such effect either on the caustic spirit itself, or on such as is so-phifticated with it.

Some have substituted to the spirit a solution of sal ammoniac and fixt alkaline salt: this liquor eludes the above method of trial, as it de-posites a saline matter on the addition of spirit of wine, in the same manner as the genuine volatile spirit: it may be distinguished by the matter, thus deposited, being not volatile but fixt; or by a fixt salt being left upon evaporating a little of the liquor; or more compendiously, by adding a drop or two of solution of silver made in aquafortis, which immediately produces a milkiness in the counterfeit, but makes no apparent change in the genuine spirit.

The addition of spirit of wine to volatile alkaline spirit affords means of judging, in some degree, of their strength or Saturation as well as of their purity. If the volatile spirit be fully saturated with salt, a quantity of highly-rectified spirit of wine, poured on it slowly down the sides of the glsss, in a cool place, produces immediately an opake dense coagulum on the surface where the liquors touch: on shaking them together, the whole becomes a consistent mass, which soon resolves by warmth into a fluid and a solid part. This is supposed by some to be a volatile soap, composed of the alkaline salt of the one spirit and the oily principle of the other, though in effect it is no more than the alkaline salt itself dislodged, by the vinous spirit from the watery fluid in which it was dissblved: the quantity of salt, thus separated, will be in proportion to the strength of the volatile spirit.

Though volatile alkalies, not caustic, appear from the above experiments to be averse to any union with vinous spirits; a solution of them even in rectified spirit is nevertheless obtainable, by adding it, along with water, in the process by which they are extricated from the sal ammoniac. For this purpose, three pints of proof spirit are put to four ounces of fal ammoniac, and six (or less) of any sixt alkaline salt, and one half of the liquor drawn off with a gentle heat†. Or sixteen ounces of quicklime and eight of sal ammoniac are powdered together, and put into a retort with thirty-two ounces of rectified spirit, and the distillation continued till all the spirit is come over ‡. This preparation has lately come into esteem both as a medicine and a menstruum.

Mixtures of volatile and vinous spirits, flavoured with different aromatic oils, and other like materials, have long been in general use under the name of sal-volatile. The college of London orders a quart of the above dulcified spirit, two drams of essential oil of nutmegs, and the same quantity of essence of lemons, to be mixed together: that of Edinburgh directs a dram and a half of oil of rosemary, and a dram of essence of lemons, to be dissolved in eight ounces of the dulcified spirit. Volatile spirits are impregnated also in the shops with asasetida, in the proportion of four ounces to five pints †, or one ounce to sixteen ounces ‡.

Offa alba Helmontii.

† Spirit, ammonia Ph. Lond.

‡ Spiritus fal. ammon. vi-vi-nofus Ph. Ed,

Splr. ammo-niae comp. Ph. Lond.

Spirit, volat. aromat. vulgo Spir. volat. oleos. & Spir. falinus aromat. Ph. Ed.

These kinds of compositions may be made extemporaneously, by dropping any proper es-sential oils into the dulcified spirit of sal ammoniac, (as now directed above by the London and Edinburgh colleges) which will readily dissolve them without the assistance of distillation. By this method, a sal-volatile may be occasionally prepared, of any particular flavour, or adapted to particular purposes: thus, in hysterical disor-ders, where the uterine purgations are deficient, a preparation of this kind, made with the oils of rue or savin, proves an useful remedy: in weakness of the stomach, oil of mint may be used; and in flatulent cases, those of aniseeds or sweet fennel seeds: these last remarkably cover the pungency of the volatile spirit, and render it supportable to the palate. The dose of these compounds is from a few drops to sixty or more.

The caustic spirit made with quicklime appears in some cases preferable, for these kinds of compofitions to the other volatile spirits; as being perfectly miscible with rectified spirit of wine, in any proportions, without any separa-tion of its volatile alkaline part; and as being a more powerful menstruum for some difficultly soluble oils. The very penetrating pungent volatile spirit, which has lately come into vogue under the name of eau de luce, is said to be made with this caustic spirit, and oil of amber that has been rectified or redistilled till it becomes limpid and loses its smell: one scruple of the oil, so rectified, and ten grains of soap, are directed to be dissolved in an ounce of rectified spirit of wine, and four ounces of the caustic spirit added gradually to this solution: the mixture generally appears milky and if required limpid may be rendered lb by distillation: some tinge it of a fine blue colour, when designed only for smelling to, by adding a drop or two of solution of copper(a).

Spir. ammon. foetid. Ph. Lond.

Spir. ammoniac fuccinat, Ph, Lond.

- volat. foet. Ph. Ed.