1279. The urine of the horse, according to Fourcroy and Vauquelin, contains of carbonate of lime 11, carbonate of soda 9, benzoate of soda 24, muriate of potassa 9, urea 7, water and mucilage 940. In addition to these substances, Brande found in it phosphate of lime. The urine of the ass, the camel, and the rabbit, have been submitted to different experiments, and their constitution has been found similar. In the urine of the rabbit, in addition to most of the ingredients above mentioned, Vauquelin detected gelatine; and the same chemist discovered uric acid in the half solid urine of domestic fowls. 'Guano, the excrement of sea-fowl, likewise contains a considerable portion of this salt.' Human urine contains a greater variety of constituents than any other species examined. Urea, uric acid, and another acid similar to it in nature called rosacic acid, acetic acid, albumen, gelatine, a resinous matter, and various salts are found in it. The human urine differs in composition, according to the state of the body, and the nature of the food and drink made use of. In many cases of disease there is a much larger quantity of gelatine and albumen than usual in the urine, and in diabetes it contains sugar. It is probable that the urine of the same animal must likewise differ according to the different nature of the food and drink used; and this will account for discordances in some of the analyses that have been published on the subject. Urine is very liable to change, and to undergo the putrefactive process; and that of carnivorous animals more rapidly than that of graminivorous animals. In proportion as there is more gelatine or albumen in urine, so in proportion does it putrefy more quickly. As this manure is very strong, it should be mixed with sawdust, weeds, &c.; and if not mixed with solid matter, it should be diluted with water, as, when pure, it contains too large a quantity of animal matter to form a proper fluid nourishment for absorption by the roots of plants. The ammonia and carbonic acid which are evolved during the decay of this species of manure, are produced in such quantities as to be highly injurious, as they are far more than the plants require, and, indeed, more than they can absorb.
