102 BOARD OF AGRICULTURE. 



bougTit ; they were used with great satisfaction ; the manufac- 

 turers could obtain certificates from tlie very first farmers in 

 every town of the value of their manures ; and yet they were 

 selling a very inferior article — that is, they were asking a much 

 too high price for the article sold. The article, it may be, was 

 good, but the price was altogether extravagant. 



The chemical test is the only reliable one for the market 

 value of fertilizers ; the only one which will bear thorough 

 scrutiny ; the only one which can be applied economically ; the 

 only one which, with the farmer's best facilities for experiment- 

 ing with manures, he can rely upon. If a farmer is so situated 

 that he can try parallel experiments on soils of precisely or very 

 nearly the same character, and can use a certain quantity — so 

 many dollars' worth of Peruvian guano on so many square rods 

 — and then use a variety of other commercial fertilizers on. 

 other pieces of land, and can crop those pieces with different 

 crops, he may come to pretty nearly as accurate an estimate of 

 values as the chemist ; but still the chemist will have a very 

 great advantage. If, for instance, a piece of land of great uni- 

 formity be divided so as to have several manures used upon it, 

 and grass and wheat and turnips and some other root crop — say 

 parsnips or carrots — grown upon it, so that each manure is tested 

 by these different crops, on tlie same soil and in varying quan- 

 tities also, a very close approximation to the actual value of the 

 manure may be obtained. One manure will be found to benefit 

 the turnip crop, while it does not essentially benefit the wheat 

 or grass crop ; one will benefit Indian corn or mangolds or some 

 rank feeding crop, while the effect upon wheat or upon turnips 

 will not be so very great ; and so the farmer who should attempt 

 to determine accurately, or the experimental farm on which any 

 such series of experiments should be undertaken, with a view 

 to determine accurately the market value of these crops, would 

 be put to immense expense, to very little purpose. A good 

 chemist would, in a short time, save them all the trouble. 



The price which agriculturists ought to pay is about that for 

 which they can procure an equivalent for any manure. Conse- 

 quently, it is not difficult, with sufficient chemical knowledge, 

 to get at a pretty fair scale of prices for the various ingredients 

 of manure. If we take the cheapest available sources of supply 

 of the most valuable ingredients of manures, we find that twenty 



