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 gum ammoniacum, the last two ingredients to be dissolved in an underground cave furnished with the conductors of electric fire.

The first official substitute for James's powder was introduced into the London Pharmacopœia of 1787. The formula was devised by a Dr. Higgins, and the experiments were made in the laboratory of the Society of Apothecaries. It was composed of equal parts of tersulphuret of antimony and hartshorn shavings. This was found to be stronger than the original, and further experiments were made for the College by Dr. Pearson, who reported in 1791 that James's powder consisted of about equal parts of oxide of antimony and phosphate of lime. The formulas in the London Pharmacopœias of 1809 and 1824 were consequently reduced in strength, one part of the antimonial salt with two parts of horn shavings being substituted. The ingredients were heated to redness in a crucible and afterwards powdered. For the Pharmacopœia of 1851, Mr. Richard Phillips experimented, and mainly confirmed Dr. Pearson's results. The formula remained as in 1824. Meanwhile the Edinburgh Pharmacopœia continued to adopt the stronger combination, while the Dublin Pharmacopœia prescribed a different preparation altogether, tartarised antimony and phosphate of soda solutions being mixed, and a precipitate consisting of teroxide of antimony and phosphate of lime being produced by precipitation by the addition of a solution of chloride of calcium and ammonia. This was a modification of a process advocated by Chevenix in a paper published in ''Phil. Trans.'', 1801. His process was recommended by Abernethy and many other of the leading practitioners of his time. In the British Pharmacopœias the simple formula of one part of antimonious oxide and two parts of calcium