Practical prescribing and dispensing for medical students / by William Kirkby.

Date:
1906
Catalogue details

Licence: In copyright

Credit: Practical prescribing and dispensing for medical students / by William Kirkby. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    WEIGHTS AND MEASURES. The Imperial System of weights and measures is official for the purposes of the British Pharmacopoeia; but for convenience in prescribing and dispensing some of the denominations of the apothecaries' weights are retained in use because the avoirdupois ounce of 437'5 grains is not a simple multiple of a grain, and does not, therefore, admit of easy subdivision. Weights. 1 Grain, granum, gr. 1 Ounce, uncia, oz. =:437'5 grains 1 Pound, libra, lb. = 16 oz. =7000 grains It is optional and convenient to use the scruple and drachm of the apothecaries' weights for quantities intermediate between the grain and ounce. I Scruple, scrupulus, 3 =20 grains 1 Drachm, draclmia, 5 =60 grains In the writing of prescriptions the symbol (3) of the apothecaries' ounce is commonly used when ordering solid drugs; but as its value is 480 grains it should only be used when that weight is required. Measures of Capacity. 1 Minim, minimum, min. 1 Fluid drachm, fluidrachma, fl. drm. =60 minims. 1 Fluid ounce, fluiduncia, fl. oz. = 8 fl. drms. 1 Pint, octarius, O. =20 fl. oz. 1 Gallon, congius, C. =8 pints The volume of 100 grains of water at 62°F. is taken as no minims. It is much more general to use the