Urine
An excellent manure, because of the substances contained in it. Of these, one of the most important is Ammonia, either uncombined, or united with various acids to form compounds. From these substances plants are able to obtain the Nitrogen required for the production of protoplasm. There are also various mineral compounds in solution in Urine, in a form available for plants; in fact, the Urine of most animals is of more value as a manure than their solid excrement. Analysis of various Urines gives the following results: Urine of cattle contains 8 per cent. of solid matters; of horses, 11 per cent.; of sheep, 13 per cent.; of pigs, 25 per cent.; and of man, from 3 to 6 per cent. Amongst the substances in Urine are Carbonates, Phosphates, Chlorides, and Sulphates of Ammonia, and of other alkalies, along with a good deal of Urea and of Uric Acid. The two last substances readily undergo chemical changes into Ammonia and its compounds. The addition to the Urine of Gypsum, or of coarse Sulphuric Acid, forms Sulphate of Ammonia, and thus prevents the loss of the Ammonia by evaporation into the atmosphere. Urine should be permitted to become stale or to putrefy before being applied to the soil. It is a very valuable manure for almost all kinds of garden produce and fruit-trees; and, when diluted with three or four times its bulk of water, may be employed in the fluid state. It may also be mixed up as a compost with soil and vegetable refuse. The mass should be allowed to ferment for some time, and may then be applied like ordinary farm-yard manure. Owing to its very strong and unpleasant smell when stale, Urine should not be freely used close to houses. Instead of being allowed to run to waste, as it so often is, arrangements should be made for collecting the farm-yard Urine into a tank, and for storing it up for use as described above.