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gas, liquor, obtained, water, air and iron

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AMMONIA (Formula, NH,; atomic weight, 17.oi. Synonyms, spirits of hartshorn, vola tile name is supposed to be derived from Ammonia, the district of Libya, where it was first prepared, or from its being first manufactured from camel's dung collected by the Arabs at the Temple of Jupiter Ammon in the same locality.

Ammonia exists in the air as carbonate of ammonium ; in rain water, especially in that of thunder showers, as nitrate ; in sea water, and in many of the mineral springs. It is present in most kinds of clay and soils, in sesquioxide of iron, and in the majority of iron ores. Sal ammoniac and ammonium alum are found as minerals, the former chiefly in volcanic regions and in some specimens of rock salt. Ammonia is obtained by the dry distillation of animal or vegetable matter containing nitrogen. The horns and hoofs of animals produce large quantities, and for this reason it is sometimes called spirits of hartshorn.

Urine is, no doubt, the oldest source of ammoniacal compounds, as sal ammonic prepared from it was an article of commerce in Europe as early as ipo. The methodical collection of urine and working it up into ammoniacal compounds, have been carried out in the neighborhood of some large towns, e.g., Paris, according to a work entitled " Industrie des Produits Ammoniacaux " we find that in Paris there are daily 2,200 tons of urine and night soil taken out of the foss& and left to settle in large reservoirs. Sulphate of iron or zinc is used as a disinfectant, and the solid matter is separated from the liquid sewerage forming 85-95 per cent., which is now called eau vanne. In three or four weeks the fermentation is complete, the urea has vanished, and there has been formed principally ammonium carbonate, along with sulphydrate, sulphite, chloride, ammo nio-magnesian, phosphate compound ammonias, and other substances of intensely disagreeable smell.

Large quantities of ammonia can be extracted from Peruvian guano, but its value as a manure is so great that the process of extraction patented by Young, in 1841, can never be remunerative.

Ammonia is also obtained from peat, from bituminous shale, and as a by-product in the manu facture of beet-root sugar.

In England ammonia is chiefly obtained from gas liquor. In the dry distillation of coal, as practiced in gas works for obtaining gas for illuminating purposes, it is necessary to purify the gas by subjecting it to a cooling and washing with water. In this process two products are obtained from the gas—an oily and an aqueous substance which, by settling in the tanks, separate from each other and form tar and gas liquor, in which many ammoniacal substances are con tained.

Ammonia is a colorless gas of an extremely pungent smell, and sharp alkaline taste. It contains one atom of nitrogen, combined with three of hydrogen, which two elementary bodies show, when free, no tendency to combine, but can be made to unite under certain circumstances, the result being ammonia. These elements, however, may be decomposed by the electric dis charge, or very slowly by heat. Ammonia gas does not support either combustion or respiration. Animals die when immersed in it. It is feebly combustible ; when issuing in a fine stream into air it may be kindled, and burns with a pale flame. It colors turmeric paper brown, and turns red litmus paper blue, both colors disappearing on exposure to air. Taste hot and strongly alka line, and is poisonous when breathed—it destroys the mucous membrane.

Liquid Ammonia is an aqueous solution of the volatile gas ammonia, and in this state is generally used in photography. Water at ordinary temperature absorbs about loo times its vol ume. A fluid dram of ammonia liquor fortior contains 15.83 grains of ammonia, and has a sp. gr. of 0.891. The liquor ammonia of the pharmacopoeia has a sp. gr. of 0.959, and a fluid dram con tains 5.2 grains of It is a common error to confound these two, but it will be seen that the ammonia liquor fortior contains 200 per cent. more ammonia. Liquor ammonia is extremely alkaline, but differs from the other alkalies in the fact of its being volatile.

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