200 BOARD OF AGRICULTURE. 



appearances, bulk or color. Every substance that holds potash, 

 phosphoric acid, lime, soda, and the nitrogenous bodies, has 

 value, and the value depends upon the amount and the condi- 

 tion in which these agents exist in the substance. K we can 

 know what the exact value is of the agent we are using, then 

 we can experiment understandingly and successfully ; but if we 

 are at work in the dark, our results will be wholly unreliable 

 and valueless. 



The results of our experiments have established this point 

 clearly, that in order to grow crops successfully, a// the sub- 

 stances needed by plants must be present in the soil in which 

 they flourish. The soils of cultivatable lands hold in a greater 

 or less proportion all that is essential to the growth of plants. 

 Sometimes one or more of these essentials is largely in excess, 

 or there is more than is needed by any crop for a succession of 

 years ; and often one or more is held in small amount, barely 

 sufficient for some crops and wholly insufficient for others. A 

 soil resulting exclusively from the disintegration or crumbling 

 of limestone rocks will be rich in the calcareous element, but 

 deficient in several of tlie other essentials. Soils resulting 

 largely from feldspathic masses and granite, will hold quite all 

 that supply the elements of nutrition to plants, and sucli are 

 therefore good. No two fields or farms are alike as respects the 

 nature of the soil ; and therefore, when the question occurs, 

 how can this or that farm be restored to fertility, it is necessary 

 to know the general composition of the soil as preliminary to 

 any intelligent attempt to bring it into good tilth. Much of the 

 confusion and doubt which prevail among farmers springs from 

 this difference which exists in soils. Farmers seek for some 

 specific manure which will insure large returns of all kinds ; 

 but no such specific exists, nor ever will. There is, certainly, 

 no specific for our bodily diseases, and therefore, doctors in pre- 

 scribing are said to feel their way in the dark. The farmer 

 who is searching for specifics is groping in thick darkness. The 

 intelligent doctor who is acquainted with the constitution and 

 idiosyncrasies of his patient, possesses in the cure of disease a 

 great advantage over one who knows nothing of such peculiar- 

 ities. The most proper business of the physician is to study 

 the peculiarities of his patients, and the most proper business 

 of the farmer is to study the physicial and chemical peculiarities 



