STALL-MANURE AND STRAW. 145 



The remaining less important and invariable, yet 

 minute, inorganic constituents (for example, common 

 salt, sulphuric acid salts, etc.) have not, for simpli- 

 city's sake, been specified. 



Without greatly erring, 1,000 pounds of perfectly 

 dry straw may be deemed equivalent to an ordinary 

 shock (thirty trusses) ; consequently one shock of 

 straw-litter, as manure, will have, according to its 

 constituents, a maximum value of twelve shillings. 

 If now it is estimated that a cow receives annually 

 two shocks of straw (about six pounds per diem) for 

 littering, and that all its solid excrements with half 

 its urine are absorbed thereby, the following propor- 

 tion of prices is exhibited : 



£ s. d. 



20,000 lbs. of solid excrements from a cow have a value of 4 10 



4,000 " urine, " « " "206 



2 shocks of straw, '' «' l' 4 



The manuring value of straw amounts, according- 

 ly, to scarcely one sixth part of the stable-muck, and 

 by increasing the littering to eight pounds per diem 

 would be raised only to one fifth. A load of fresh 

 stall-manure, weighing 15 cwt., would have, in ac- 

 cordance with this calculation, a value of 9^., of 

 which 7^. 6o?. must be allowed for the animal ex- 

 crements, and 1^. 6(f. for the straw of the manure. 



Straw, strictly speaking, operates as manure less 

 by its organic and humus-forming ingredients and 

 by its nitrogen than by its mineral constituents (pot- 

 ash, phosphoric acid, and lime). My conclusion is 

 drawn from the following examination of two 

 13 



