MODERN HIGH FARMING. 93 



Where Stassftirt salts are used by manure manufacturers, a con- 

 siderable danger sometimes arises from their containing a serious 

 enemy to vegetation, in the form of chloride of magnesium, which, 

 when not driven off by the application of sufficient heat, constitutes 

 a positive poison to plant life. 



When the lands under cultivation are characterized by the homo- 

 geneity, or equally balanced proportion of their chemical elements, 

 the yearly application of compound, or "complete" manures will 

 sustain their health and strength, and increase their fecundity, but 

 where, as in most cases, one of the essential elements is alone found 

 to be wanting, the others being present in abundance, the temporary 

 employment of a " simple" manure is clearly indicated. 



Supposing, for instance, a soil to be rich in nitrogen and potash, 

 but devoid of phosphoric acid, and presuming cereals to be the de- 

 sired culture, the repeated introduction of phosphatic materials will 

 accomplish what is necessary, until after about the third crop, when 

 the nitrogen will probably have become exhausted. 



That the eventual recourse to compound or "complete" ma- 

 nures is essential, therefore, may be considered conclusive, even if 

 we had not for our guidance the experience of our grandfathers, 

 who, having always contented themselves with their stable offal, 

 were finally compelled to take refuge in the system of rotation, be- 

 cause their manures were incapable of returning, pro rata, the ele- 

 ments their crops had taken away. To set forth any general formula 

 for universal use and for every kind of culture, would be as contrary 

 to our theories as the swallowing of quack specifics for every hu- 

 man ill is against our practice, nor would it be consistent with the 

 doctrine, "do all that you have to do with a full knowledge of what 

 you are doing!" 



It is time that what has been so long and so exclusively known 

 to chemists, should become known to the farmer, and that of two 

 things he should at once choose one. Let him either deny the truth 

 and boldly refuse to be convinced, or fall into the ranks and profit 

 by those lessons taught by nature. They who, dissatisfied with the 

 miserable results of their traditionary usages, seek to raise their minds 



