Volume 2

The elements of experimental chemistry / by William Henry.

  • Henry, William, 1774-1836.
Date:
1815
Catalogue details

Licence: Public Domain Mark

Credit: The elements of experimental chemistry / by William Henry. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

    25/586 (page 7)
    SECT. HI. niOSPIIATES. T druggists), mixed with one of acetite of lead, in the pro- portion of one part of the former salt to 1^ of the latter, yields a precipitate of phosphate of lead, from which phos- phorus may be procured by distillation. SECTION III. Phosphates. With alkaline and earthy'bases, the phosphoric acid com- poses a class of salts called Phosphates, which have the fol- lowing generic characters. 1. When heated with charcoal, they are not decomposed, nor is phosphorus obtained. 2. They melt, before the blow-pipe, into a hard globule, sometimes transparent, at others opake. .3. They are soluble in nitric and muriatic acids, without eiFei-vescence, and are precipitated from those acids by lime- water and pure ammonia. 4. They are decomposed, in part, by sulphuric acid, and yield a liquor which, on evaporation and distillation with charcoal, affords phosphorus. The phosphate of soda is the only one of these salts which has any important use. It has been introduced into medicine, by Dr. Pearson, as a purgative, the purposes of which it answers, unaccompanied by any nauseous taste. Tlie phosphate of lime, besides being found in the earth in a mineral form, constitutes a large part of the solid matter of animal bones. As an enumeration of these salts can scarcely be into- fcsting to the general student, and as the properties of the various salts, already described, furnish abundant discrimi- nating charactei's of the different alkalis and earths, I deem it sufficient to refer, for a detailed account of them, to Dr, Thpmson'.s Eleipe^JtSj or L3 Grange's Manual,