222 Oil the Manuring of Grass Land. 



Meadow Hay. Eye Grass. 



Boussingault. Thompson. 



Potash 18-11 



Soda 1-35 



Lime 22-95 



Magnesia 6-75 



Oxide of iron, alumina, &c. 1-69 



Phosphoric acid .. .. 5-97 



Sulphuric acid .. .. 2-70 



Chlorine 2-59 



Silica 37-89 



100-00 100-00 98-15 



The following analysis is by M. Isidore Pierre, translated in 

 the 'Chemist,' August, 1857, from ' Comptes Rendus.' This hay 

 gave 69-011 grammes of ash per kilogramme : — 



Grammes. 



Silica 19-406 



Phosphoric acid 4-440 



Lime 12-637 



Ma2;nesia 1-824 



Soda 15-956 



Potassa 12-527 



66-790 



These figures will be conclusive. No thoughtful reader will 

 require one word of argument to prove that he must supply his 

 grass-land with minerals if he intend it to produce the crops which 

 it is capable of yielding. It should also be borne in mind that 

 •75 per cent, of ash is probably below the average, and that in 

 some cases this quantity is doubled. I have myself recently 

 burnt a sample of hay sent to me from London which left 1-5 

 per cent, of ash, and it was not artificially dried in the laboratory. 



But the case is only half stated. We must make the same 

 inquiry relative to nitrogen which we have made relative to 

 minerals. What quantity of this is removed annually from each 

 acre which produces the crop I have supposed ? 



Tlie nitrogen in hay varies, and hence different chemists give 

 different estimates of its quantity. I subjoin three, and the lowest 

 of them is calculated to make the farmer think — may I not say 

 when added to what precedes, to make him reform his practice? 



Boussingault estimates the nitrogen of liay at 1*15 per cent., 

 according to which we shall take from each acre of land per year 

 64*4 lbs., corresponding to 119'6 lbs. of ammonia.* 



* By ammonia here is signified the oxide of ammonium, NH4O, the compound 

 intended by that name when we speak of sulphate NH4 O, SO3 + HO, nitrate 

 NH4 0, NO.i, or carbonate 2 NH4 O, 3 CO^ of ammonia. They who wish can 

 easily alter the figures to suit the formula NH^. 



