238 THE SYSTEM OF FARM-YARD MANURING. 



contains, if the amount of the available food elements 

 that serve to produce the crops, which is the really im- 

 portant point, cannot be determined. 



With such absurd assertions they absolutely hood- 

 wink our ' practical ' farmers, who, but for them, might 

 see clearly into matters, but who appear only too will- 

 ing to accept any assertion that will only leave them at 

 peace, and save them the trouble of c thinking.' 



I remember a case w T here a swindler offered to sell 

 to a wealthy gentleman, at a high price, a mine of 

 almost pure oxide of aluminium, after having shown 

 him, from chemical works, that oxide of aluminium was 

 indispensable for the production of the metal alumin- 

 ium, the market price of which was as much as 41. per 

 pound, and that the ore of the mine offered for sale con- 

 tained nearly 80 per cent, of that valuable metal. The 

 purchaser was not aware that the ore in question is gen- 

 erally known as ' pipe-clay,' an article of almost nom- 

 inal value, and that the high price of the metal arises 

 from the many changes through which the oxide has to 

 pass to effect its reduction to the metallic state. 



It is generally the same with the great stores of pot- 

 ash in the soil. The alkali in the ground, to answer 

 the intended purpose, must, by the agriculturist's art, 

 be converted first into a certain form, in which, alone, 

 it is available as food for plants ; and if he does not 

 understand how to effect this conversion, all the potash 

 in his soil is of no earthly use to him. 



The notion that the farmer need only restore to his 

 land certain substances, without troubling himself about 

 the rest, might not be prejudicial if those who enter- 

 tained it confined the application to their own farms ; 

 but, as a matter of instruction to others, it is untrue 

 and quite exceptionable. It is calculated for the low 

 intellectual standard of the practical man, who, if he in 

 any way succeeds, by certain alterations, in his system, 

 or by the use of certain manuring agents in obtaining 

 better results than another, attributes his success to his 

 own sagacity rather than to the superior quality of his 

 land. He does not even know that the other has tried 



