A manual of pharmacy / By William Thomas Brande.

  • Brande, William Thomas, 1788-1866.
Date:
1833
Catalogue details

Licence: Public Domain Mark

Credit: A manual of pharmacy / By William Thomas Brande. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

    18/564 (page 4)
    calyx is small, bell-shaped and five-toothed; the corolla is divided into five narrow, yellow segments; the filaments are numerous, capillary, bearing roundish yellow anthers; the germen is conical, with a slender style and simple stigma ; and the pods, which are three or four inches long and half an inch broad, contain several flattish, brown seeds. The gum is im- ported, -packed in casks, from Barbary and Morocco, in drops or tears, and in small fragments of a pale straw-colour, and more or less transparent or translucent. It is frequently mixed with what is known in the trade under the name of gum Senegal, also an African product, and probably indiscrimi- nately collected from several trees. Gum Arabic exhibits the chemical characters of pure gum. Its specific gravity is 1'35. It is tasteless, readily soluble in water, but insoluble in pure alcohol and ether. Its aqueous solution, if concentrated, is very little prone to change; if much diluted, it becomes acetous when kept. This solution is decomposed by subacetateof lead, and a precipitate is formed composed of gum and oxide of lead. The alkalies and diluted acids dissolve gum without change, but the concentrated acids decompose and alter it. Nitric acid converts a portion of it into mucic or saccholactic acid. It consists of carbon, oxy- gen, and hydrogen. The medical uses of gum Arabic are soon told. It is nutri- tious to a considerable extent, and is placed among the sub- stances termed demulcents. Its chief use is to suspend differ- ent insoluble substances in water; hence it is often mixed Avith oils, resins, gum resins, and the like. The mucilago acacica of the Pharmacopoeia is made by dissolving the powdered gum in twice its weight of boiling water; a solution too thick for most purposes. To allay the irritation excited by a cough, mixtures of mu- cilage and oil, or emulsions, are often of some service; and they may be rendered palatable, and even pleasant, by the addition of sugar and some very slight aromatic. Thus— R Mucil. Acaciao ^j. Olei Amygd. Syrup. Tolutani sa iys. AquDB Cinnam. f 5ij. distillat. f 5iV' M. fiat Mistur. cujus sumatur parum subinde. Or the diluted mucilage may be more simply prescribed as the vehicle of an expectorant; thus— R Mucilagnis acaciao gij. Syrupi Mori, ^j. Acpia) RosiB, giij. Tinct. ScilloP, 3j. M. Cochloaria duo vel tria ampla sumuutur subinde.