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is consumed and decomposed, and the less of the narcotic products of combustion are created than when it burns badly. It is, therefore, important that such fertilizers be used as will best promote the process of combustion.

It is said that too much nitrogen tends to produce a heavy, coarse growth, accompained by the formation of a large per cent. of nicotine and albuminoids in the leaf. Hence it is best to use this element in not too large quantites.

Besides adding stable manure, the deficiencies in nitrogen may be supplied by nitrate of soda, nitrate of potash, sulfate of ammonia, cotton seedmeal, castor pomace, and etc. It is said that phosphoric acid is more generally deficient in the soil than the other mineral constituents required by plants and needs to be supplied in