REPORT ON PHOSPHATIC AND AMMONIACAL MANURES. 



137 



We subjoin the following table of particulars : — 



REPORT ON PHOSPHATIC AND AMMONIACAL MANURES. 



By Robert J. Thomson, Grange, Kilmarnock. 



[Premium — Ten Sovcrc igns. ] 



Artificial manures, in spite both of the nitrogen and the 

 mineral theories, are practically comprised in two great classes : 

 Ammoniacal — or, what would, perhaps, be a better term, Nitro- 

 genous — and PJwsphatic; and according to the quantity and con- 

 dition of these constituents in a manure, so is its value. In 

 stating this so broadly, we do not for one moment assert that 

 either nitrogen or phosphoric acid is more valuable intrinsically 

 than any other plant constituent. It is more probable that each 

 is alike valuable. Chemical analysis has revealed the almost 

 unvarying proportional amount of each substance in the plant, 

 and has shown that these are again found in like proportion in 

 the animal. At all events, the amount of each of the combus- 

 tible elements is so large that they, at least, are evidently and 

 indisputably necessary ; and the experiments of Prince Salm 

 Horstmar have sufficiently proved, that when any one single con- 

 stituent of the ash, or incombustible matters of the plant, is with- 

 held from the soil, the plant cannot grow to maturity.* Neither 

 do we mean to ignore from a place in the category of artificial 

 manures those substances other than phosphatic and nitrogenous 



• » 



Anderson's Agricultural Chemistry," p. G3. 



