Dr. Pereira's Elements of materia medica and therapeutics : abridged and adapted for the use of medical and pharmaceutical practitioners and students and comprising all the medicines of the British Pharmacopœia, with such others as are frequently ordered in prescriptions or required by the physician / edited by Robert Bentley and Theophilus Redwood ; with an appendix.

  • Jonathan Pereira
Date:
1874
Catalogue details

Licence: Public Domain Mark

Credit: Dr. Pereira's Elements of materia medica and therapeutics : abridged and adapted for the use of medical and pharmaceutical practitioners and students and comprising all the medicines of the British Pharmacopœia, with such others as are frequently ordered in prescriptions or required by the physician / edited by Robert Bentley and Theophilus Redwood ; with an appendix. Source: Wellcome Collection.

    69/1180 (page 37)
    [§ Ammonise Phosphas. Phosphate of Ammonia. 2NH40,HO,P05 or (NH4)2HP04. Take of Diluted Phosphoric Acid » . 20 fluid ounces. Strong solution of Ammonia . . a sufficiency. Add the ammonia to the phosphoric acid until the solution is slightly alkaline, then evaporate the liquid, adding more ammonia from time to time, so as to keep it in slight excess, and when crystals are formed, on the cooling of the solution, dry them quickly on filtering paper placed on a porous tile, and preserve them in a stoppered bottle. Characters and Tests.—In transparent colourless prisms. Soluble in water, insoluble in rectified spirit. When treated with caustic potash, ammonia is evolved. The aqueous solution gives a yellow precipitate with nitrate of silver. If twenty grains of this salt be dissolved in water, and solution of ammonio-sulphate of magnesia added, a crystalline precipitate falls, which, when well washed upon a filter with solution of ammonia diluted with an equal volume of water, dried, and heated to redness, leaves 16*8 grains. Dose, 5 to 20 grains.] This salt, as met with in commerce, is usually made by treating bone ash with sulphuric' acid, as in the process described for phos- phate of soda, and converting the acid phosphate of lime so pro- duced into phosphate of ammonia by adding carbonate of ammonia, when phosphate and carbonate of lime are precipitated, and phos- phate of ammonia is left in solution. As thus produced, however, the phosphate of ammonia is generally mixed with a little sulphate, which may be detected by adding chloride of barium to a solution of the salt previously acidified with nitric acid. If there be sulphate present, a precipitate will be formed, insoluble in diluted nitric acid. Therapeutics.—Dr. Garrod states that ' it is capable of dissolving a considerable amount of urate of soda, and clinical experience has shown that it is of great value in the treatment of certain urinary diseases when a tendency to uric acid calculi exists, and also in certain conditions of the gouty habit.' Dose, 5 to 20 grains. Ammoniae Sulphas. Sulphate of Ammonia. NH40,S03 or (2m4)2S04. Prepared, by the aid of sulphuric acid, from the ammoniacal liquors obtained in the distillation of coal, &c, and purified by crys- tallisation or sublimation.