In the subjoined tables the composition of a great variety of different kinds of guano is given. Most of these are averages deduced from a considerable number of analyses of good samples. Those of some kinds of guano, such as Peruvian, which present a considerable amount of uniformity, afford a sufficiently accurate idea of the general composition of the variety, but in other cases they are of less value, because the imports of different seasons, and even of different cargoes, differ so greatly in composition that no proper average can be made. Several of these varieties are already exhausted, the importation of others has ceased, and new varieties are constantly being introduced. _Table showing the Average Composition of different varieties of Guano._ -------------------+--------+-------+-------------+---------------------------+ |Angamos.|Peru- | ICHABOE. |Bolivian or Upper | | | vian. | |Peruvian. | | | +-------------+------+-----------+--------+ | | |Old. |New. |Old. |Government.|Inferior| -------------------+--------+-------+------+------+------+-----------+--------+ Water | 12.36 | 13.73 |24.21 |18.89 | 12.55| 16.44 | 14.15 | Organic matter }| | | | | | | | and ammoniacal }| 59.92 | 53.16 |39.30 |32.49 | 35.89| 12.28 | 26.14 | salts }| | | | | | | | Phosphates | 17.01 | 23.48 |30.00 |19.63 | 27.63| 56.09 | 23.13 | Sulphate of lime | ... | ... | ... | ... | ... | ... | 9.65 | Carbonate of lime | ... | ... | ... | ... | ... | ... | 12.87 | Alkaline salts | 7.20 | 7.97 | 4.19 | 8.82 | 15.29| 11.33 | 5.97 | Sand | 3.51 | 1.66 | 2.30 | 6.72 | 8.64| 2.81 | 8.09 | +--------+-------+------+------+------+-----------+--------+ | 100.00 |100.00 |100.00|100.00|100.00|100.00 |100.00 | Ammonia | 21.10 | 17.00 | 8.50| 10.42| 8.99| 2.57 | 3.26 | Phosphoric }| | | | | | | | acid in alkaline}| 1.20 | 2.50 | ... | ... | ... | 3.11 | ... | salts }| | | | | | | | -------------------+--------+-------+------+------+------+-----------+--------+