ARTIFICIAL MANURING. 145 



I have been fortunate to remove the difficulties which are 

 opposed to the appHcation of a mere mixture of the elements 

 of manure. If we employ the different elements of manure 

 exactly in those proportions in which they are necessary, 

 according- to experience, for a rich crop of wheat, peas, tur- 

 nips, potatoes, and if, at the same time, we leave them in 

 their common state, they do not produce that etlect which we 

 mig-ht have expected ; the cause of this is, that the ditierent 

 elements of manure i^ossess a very unequal solubility; the 

 ammonia evaporates, the soluble elements are carried otf by 

 the rain, and the effect is more in proportion with the amount 

 of those ing-redients of the manure which are less soluble. 



I have found means to give to every soluble ingredient of 

 manure, by its combination with others, any degree of solu- 

 bility, without altering- its effect on veg-etation. I g-ive, for 

 instance, the alkalies in such a state as not to be more solu- 

 ble than g-ypsum,i which, as is well known, acts throug'h 

 many years, as long- as a particle of it remains on the acre. 



The mixture of the manure has been adapted to the mean 

 quantity of the rain in this country ; the manure which is 

 used in summer has a g-reater deg-ree of solubility than that 

 used in winter. Experience must lead to further results ; 

 and in future the farmer will be able to calculate the amount 

 of produce of his fields, if temperature, want of rain, &c., do 

 not oppose its coming- fairly into action. 



I must, however, observe that the artificial manures in no 

 ■way alter the mechanical condition of the fields, and they do 

 not render a heavy soil more accessible to air and moisture. 

 For such fields the porous stable manure will always have its 

 g-reat value : it can be given together with the artificial 

 manure. 



All manure which is to be used during the winter contains 

 a quantity of ammonia corresponding- with the amount of 

 nitrogen in the grain crops which are to be grown. Expe- 

 riments in which I am at present engaged will show whether 

 in future times the cost of this manure can be greatly les- 

 sened by excluding half or the whole amount of ammonia.^ 



' Equal parts of carbonate of potash and carbonate of lime (chalk), 

 melted together, will dissolve in 460 parts of water. Increase of chalk 

 lessens, while a larger proportion of the other ingredient increases, the 

 solubility. E. N. H. 



* Dr. Krocker, in his laboratory, has determined, in the course of the 

 last term, the ammonia present in moist soils of great varied physical pro- 

 perties. The results are still unpublished; but he remarked to me one 



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