+---------+--------------------------+--------------------------+ | | HORSE. | COW. | | +-------------+------------+-------------+------------+ | | Natural. | Dry. | Natural. | Dry. | | +-------------+------------+-------------+------------+ | |Urine.| Dung.|Urine.|Dung.|Urine.| Dung.|Urine.|Dung.| | +------+------+------+-----+------+------+------+-----+ |Carbon | 4.46| 9.56| 36.0| 38.7| 3.18| 4.02| 27.2| 42.8| |Hydrogen | 0.47| 1.26| 3.8| 5.1| 0.30| 0.49| 2.6| 5.2| |Nitrogen | 1.55| 0.54| 12.5| 2.2| 0.44| 0.22| 3.8| 2.3| |Oxygen | 1.40| 9.31| 11.3| 37.7| 3.09| 3.54| 26.4| 37.7| |Ash | 4.51| 4.02| 36.4| 16.3| 4.68| 1.13| 40.0| 12.0| |Water | 87.61| 75.31| 0.0| 0.0| 88.31| 90.60| 0.0| 0.0| | +------+------+------+-----+------+------+------+-----+ | |100.00|100.00| 100.0|100.0|100.00|100.00| 100.0|100.0| +---------+------+------+------+-----+------+------+------+-----+ Hence, weight for weight, the urine of the horse, in its natural state, contains three times as much nitrogen as its dung; that of the cow twice as much; and the difference, especially in the horse, is still more conspicuous when they are dry. It is obvious that the quality of farm-yard manure must depend--1. On the kind of animal from which it is produced; 2. On the quantity of straw which has been used as litter; 3. On the nature of the food with which the animals have been supplied; 4. On the extent to which its valuable constituents have been rendered available by the treatment to which it has been subjected; and 5. On the care which has been taken to prevent the escape of the urine, or of the ammonia produced by its decomposition.