Copy 1

The London dispensatory / By Anthony Todd Thomson.

  • Anthony Todd Thomson
Date:
1811
Catalogue details

Licence: Public Domain Mark

Credit: The London dispensatory / By Anthony Todd Thomson. Source: Wellcome Collection.

    142/944 (page 6)
    is insipid, inodorous,. and dissolves completely away in the mouth. Its specific gravity is 1°4523. It is often mixed with the guin Senegal, which is as pure, and with other gums less pure, particularly a kind brought from the East Indies, which is darker-coloured and less soluble'. Gum.is soluble in water, either cold or hot, and forms a viscid solution; which, if evaporated, becomes very thick and adhesive, and at length the gum is obtained in a concrete . form, equally soluble as before. It is also soluble in the ve- getable acids; but is insoluble in alcohol, ether, and in oils: yet, owing to its viscidity, it renders by trituration both the vola- tile and fixed oils and resins miscible with water, and retains them together in the form of a white opaque mixture. Con- centrated sulphuric acid blackens, and partially decomposes it, and acetic acid is produced: strong nitric converts it into the oxalic, malic, and saccholactic acids : muriatic exerts very lit- tle action on it; but the oxymuriatic changes it into citric acid, Solutions of. the: alkalss and alkaline earths dissolve it without producing on it much change. For an account of the action of other agents on it, see Mucilago acacia. ‘The chemical analysis. of gum shows that its constituents are carbon, hydrogen, and oxygen, with a small proportion of nitroge en and lime; w hich last element is supposed to render it incapable of undergoing the fermentative process *. Medical properties. —Gum exerts no action on the living sy- siem}; but is asimple demulcent, serving to lubricate abraded snrtices, and involve acrid matters in the prime vie. In the solid form it is*scarcely ever given, unless to sheath the fau- ces, and allay the tickling irritation which occasions the cough io catarrh and -phthisis pulmonalis ; in which cases a puts ‘ot it is allowed to dissolve slowly in the mouth. It is chiefly used in the state of mucilage. Vide Mucilago acacie. _Officinal preparations. Mucilago acacie. L. ~.D. LEmulsio mi- mosee nilotiwe. E. Emulsio arabica. D. Mistura cornu usti. L. D. Mistura crete. L.D. Mistura moschi. L. Confectio amygdale. L. Pulvis crete compositus. L. Pulvis tragacanthe compositus. L. chisci- carbonaiis calcis. E. Troe. gly cyrrhince glatre. E. Troe. glycyrrhizce cum opto. E, Troc. gummosi. E. ‘ ACETOSZ FOLIA. ° Vide Rumex Acetosa. ACETOSELLA. - Vide Oxalis Acetosella. ACETUM. Lond. Acipum acerosum. Edin. AcrTUuM Vint. Dub. Vinegar. ; This ts a wel] known acid liquor, pisdated by exciting the 1 Gum exudes from the cherry, plum, and other trees of the genus Prunus, im this coyntry. — 9 Murray's Chemistry, vol. iv. 180. : “8 It is sometimes used as foud by the Moors,