BROMINE AND ITS DERIVATIVES (BROMIDES, BROMATES, ETC.). Bromine is a dark-reddish-brown, vola tile fluid, emitting pungent and acrid fumes, caustic in action and taste. It is sparingly soluble in water (1 to 33), very soluble in chloroform, and likewise in ether and alcohol, both of which, however, it gradually decomposes. It combines freely with bases to form salts.
As regards the bromates, the small proportion of bromine contained entitles them to consideration only in connection with their respective bases. The list of bromides is somewhat extended, there being no less than seventeen salts, and these, with half a dozen bromates and a number of other compounds, bring the total of bromine derivatives up to thirty one. Some, however, are to be regarded as chemicals purely, or chemical curiosi ties, rather than medicaments, and a few are so rare or expensive as to inhibit gen eral employment.
Bromide of ammonium is a white, granular salt that may, however, with exposure to light and air take on a more or less yellowish hue. Its action is prac tically the same as that of the potassium, sodium, calcium, lithium, and strontium salts, at least as regards the nervous sys tem. It also, in Small doses, is, to some extent, an alterative and hepatic stimu lant; but in this particular is no better than, and perhaps not so active as, potas sium bromide. It is the least palatable of the bromine salts, has a pungent, saline flavor (bromine taste), and is odorless.
Calcium bromide is capable of evolv ing SO per cent. of bromine: a propor tion greater than obtains to any other bromide; hence it has been lauded as a succedaneuin for all the salts of alkaline base. It is had as a white, deliquescent salt, possessed of the usual pungent saline taste.
Lithium bromide presents much the same physical properties as the fore going; is sharp and bitter to the taste, white, granular, odorless, and the most difficult of all the salts to keep, owing to its deliquescent character.
Potassium bromide appears as color less, odorless, cubical, translucent, non hygroscopic crystals of bitter, pungent, saline taste, and contains an average of 67 per cent. of bromine.
Sodium bromide exhibits a consider ably larger percentage (77.5) of bromine than its potassic congener, and, though it has characteristic bromine taste, it is most palatable of all the salts, and the best borne by the stomach, though this latter claim has been disputed in favor of strontium bromide. It is a white, odorless salt, fairly permanent under all ordinary conditions of the atmosphere, and is found in the shops in two forms: as a granular powder and as small, mono clinic crystals.
Strontium bromide is a comparatively recent addition to the materia medics, and occurs in colorless, odorless crystals, only less deliquescent than lithium bro mide, and possessed of the usual bitter. saline flavor; it contains 65 per cent. of bromine.
Bromal, tribromaldeliyde, or tribro macetyl-oxide, is a limpid, colorless, oily liquid possessed of a peculiar, sharp odor and irritating taste, obtained through the decomposition of alcohol by bro mine; it is soluble in water, alcohol, and ether, but is not employed medic inally. Its derivative, bromalhydrate, however, was introduced with a view of affording an analogue of, and substitute for, chloral-hydrate, but has failed to secure the favor of medical men so con fidently expected. It is a crystalline solid with the taste of bromal.
Bromalin, or bromethylformamide, contains only about half as much bro mine as potassium bromide,—i.e., about 24 or 25 per cent.,—and offers no ad vantages over the common bromide salts; hence requires little attention. It must not be confounded with bromelin: a preparation representing the digestive principle embodied in the pine-apple.
Bromamide is a synthetic body ob tained by the union of bromine and formamide, and occurs in colorless, odor less, needle-shaped crystals insoluble in hot, but slightly soluble in cold, water, freely so in hot alcohol, and also in ether.