Phosphoric acid—as bone-ash, mixed with sufficient sulphuric acid to convert most of the insoluble earthy phosphate of lime into sulphate and soluble superphosphate of lime.
Sulphuric acid—in the phosphatic mixture just mentioned; in sulphates of potash, soda, and magnesia; in sulphate of ammonia, etc.
Chlorine—in muriate of ammonia.
Silica—as artificial silicate of soda.
Other constituents were supplied as under:
Nitrogen—as sulphate and muriate of ammonia; as nitrate of soda; in farm-yard manure; in rape-cake.
Non-nitrogenous organic matter, yielding by decomposition, carbonic acid, and other products—in yard manure, in rape-cake.
The artificial manure or mixture for each plot was ground up, or otherwise mixed, with a sufficient quantity of soil and turf-ashes to make it up to a convenient measure for equal distribution over the land. The mixtures so prepared were, with proper precautions, sown broadcast by hand; as it has been found that the application of an exact amount of manure, to a limited area of land, can be best accomplished in that way.
The same manures were used on the same plot each year. Any exceptions to this rule are mentioned in foot-notes.