I. II. III. Urate of ammonia 10.70 9.0 3.24 Oxalate of ammonia 12.38 10.6 13.35 Oxalate of lime 5.44 7.0 16.36 Phosphate of ammonia 19.25 6.0 6.45 Phosphate of magnesia and ammonia ... 2.6 4.20 Sulphate of potash 4.50 5.5 4.23 Sulphate of soda 1.95 3.8 1.12 Sulphate of ammonia 3.36 ... ... Muriate of ammonia 4.81 4.2 6.50 Phosphate of soda ... ... 5.29 Chloride of sodium ... ... 0.10 Phosphate of lime 15.56 14.3 9.94 Carbonate of lime 1.80 ... ... Sand and alumina 1.59 4.7 5.80 Water 9.14 } } 32.3 23.42 Undetermined humus-like organic} 10.00 } matters } } ------ ----- ------ 100.48 100.0 100.00 These analyses illustrate two points--_first_, that in some samples the decomposition has advanced to a greater extent than in others; for we observe that the quantity of uric acid, or rather of urate of ammonia, is greatly less in the last analysis than in the other two, and much smaller than in the fresh dung, which contains from 50 to 70 per cent of uric acid; and _secondly_, that guano is rich in all the constituents of the plant, but especially in ammonia, the best form in which nitrogen can be supplied, in uric acid which by decomposition yields ammonia, and in phosphoric acid. But such analyses are too elaborate for ordinary purposes, and much less convenient for comparison and for estimating the value of the guano than the shorter analysis commonly in use, which gives the water, the loss by ignition (that is, the sum of the organic matters and ammoniacal salts), the phosphates, the alkaline salts, and the quantity of phosphoric acid contained in them, and existing there in a state similar to that in which it is found in the soluble phosphates of a superphosphate. In addition to these, the quantities of sand and other less valuable ingredients are also stated.