Like nitrate of soda, but even to a greater extent, its most favourable action is obtained when it is applied along with other manurial ingredients. It should be applied at least a month earlier than nitrate. It has been shown that in the case of chalky soils a certain loss of ammonia in sulphate of ammonia is apt to take place, due to the action of the lime; and this leads us to point out that, in preparing mixed manures, care ought to be taken that it is not mixed with any compound containing free lime or caustic alkali, as otherwise loss of ammonia will ensue. It should never, for example, be used along with basic slag. FOOTNOTES: [212] From experiments by Lehmann and others with buckwheat and maize, it would seem that certain plants may prefer, at certain stages of their growth, ammonia to nitrates. In the case of maize, ammonia may be preferred in the early stages of growth, while nitrates are preferred as it becomes more mature. In view, however, of our present knowledge of nitrification, it may well be doubted whether the conclusions arrived at from Lehmann's experiments can be accepted. [213] As the expense of converting the ammonia present in the ammoniacal liquor is considerable, the practice of using the liquor itself as a manure has been advocated; but as an objection to this it must be urged that, besides being so bulky a manure, the liquor contains various substances poisonous to plant-life. [214] See Appendix, p. 358. [215] Some crops, however, may with advantage be treated with larger quantities of sulphate of ammonia, such as mangels and potatoes. APPENDIX TO CHAPTER X. NOTE (p. 355). The following table will exhibit the production of sulphate of ammonia in this country from 1870 to 1892:-- Year. Tons. | Year. Tons. 1870 40,000 | 1882 72,000 1871 41,000 | 1883 75,000 1872 42,000 | 1884 87,000 1873 43,000 | 1885 97,000 1874 45,000 | 1886 106,500 1875 46,000 | 1887 113,700 1876 48,000 | 1888 122,800 1877 52,000 | 1889 132,000 1878 55,000 | 1890 140,000 1879 57,000 | 1891 143,500 1880 60,000 | 1892 157,000 1881 65,000 The following table exhibits the sources, and the respective quantities from each source, of the last seven years' production:-- 1886. 1887. 1888. 1889. 1890. 1891. 1892.