LIQUOR AMMONI.E ACETATIS.

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acetic acid, unite with one equivalent, or 17 parts of ammonia; whileone and a half equivalents, or 33 parts of carbonic acid, are evolved.

INGREDIENTS USED. RESULTS.

I eq. Sesquicarb. lj eq. Carb ic . Acid 33____l| eq. Carbonic Acid .... 33

Amm. ... 50 cl eq. Ammonia. . 17 _

1 eq. Acetic Acid. 51 -—d eq. Acetate Ammonia . . 68

In the above diagram no notice has been taken of the water in thehydrated sesquicarbonate of ammonia, nor of that in the vinegar

Properties. —When pure, this liquid is colourless. Any tint, there-fore, which the solution of the shops may have, is referable to impuritiesin either the vinegar or the sesquicarbonate. Filtering it through pow-dered animal charcoal will usually remove any yellow or brown colourwhich it may have. If quite neutral, it will affect neither turmeric norlitmus paper. It is better, however, to have a slight excess of acid pre-sent than of sesquicarbonate ; for if the latter predominate, the solutionis much more irritant; and if employed as a collyrium, might produceinconvenient results.

Characteristics. —It is totally dissipated by heat. When concen-trated it evolves vapours of acetic acid on the addition of strong sul-phuric acid, and gives out ammonia if potash or lime be mixed with it.

Composition. — By evaporating a saturated solution of acetate ofammonia under the exhausted receiver of the air-pump, and over sul-phuric acid, crystals of the acetate are obtained. They are transparentoblique rhomboidal prisms, and consist, according to Dr. Thomson, of

Eq. Eq. wt. Percent.

Acetic Acid. 1 . . . . 51 ... . 38*931

Ammonia.1 . . . . 17 ... . 12*977

Water. 7 . . . . 63 ... . 48*091

Crystallized Acetate Ammonia 1 . . . . 131 .... 99*999

The quantity of dry or anhydrous acetate of ammonia contained in thesolution kept in the shops, varies with the strength of the distilledvinegar. Now, according to Mr. Phillips, 100 grains of distilled vinegarshould saturate 13 grayis of crystallized carbonate of soda. This wouldindicate the presence of 4 - 6 per cent, of acetic acid ; and, consequently,100 grains of liquor ammonias acetatis, prepared from such vinegar,would consist of

Acetate of Ammonia. 6*040

Water. 93*959

Liquor Ammonias Acetatis (Ph. L.) 99*999

Impurities. —This solution ought neither to be discoloured by the ad-dition of hydrosulphuric acid, nor to throw down any precipitate by nitrateof silver or chloride of barium. These substances, therefore, may beemployed to detect, respectively, metallic matter, hydrochloric acid ora chloride, and sulphuric acid. Pure acetate of ammonia occasions noprecipitate with diacetate or acetate of lead; but the liquor ammonia;acetatis of the shops usually does, owing to the presence of some freecarbonic acid or sesquicarbonate of ammonia.

Physiological Effects. —In small doses this solution is regarded astemperant and refrigerant: in large doses, diaphoretic and diuretic.These effects, however, are not very obvious. Wibmer [die Wirkimg, &c.)took it in moderate doses, yet did not observe any diaphoretic, diuretic,