13 



This is, however, the gain over manure spring appHed. If we 

 take plot 7, where $12.25 worth of manure was fall applied, 

 we get a yield of 16. 48 tons, a gain of 0.63 tons in favor of 

 manure. 



Or, take plots i, 4, 7, and S, another series that may be com- 

 pared, because the fertilizer used on each represents the same 

 cost. 



Cost of fertilizer Yield 



per half acre. per acre. 



Plot 4, manured Feb. II, 3>^ cords per half acre, $12.25 10.18 tons. 



" 7, " fall, " " " 12.25 16.48 " 



" 8, " " " " " 12.25 16.13 " 



Average • • 14.26 



p, ( bone-black, 404 lbs. per half acre, > 



chemcals ] muriate of potash, I22>^ lbs. " [ 12.25 IQ-SS " 



Chemicals, ^ s^iph^te of ammonia, 86 lbs. " ) 



Gain resulting from chemicals instead of manure . . 5.59 " 



In a series of experiments carried on at Durham, under the 

 supervision of Mr. D. E. Stone, the following results were 



obtained : 



Cost per Yield per 

 half acre. acre. 



Plot 2, (one half acre), 5 cords manure, $i7-5o '5 08 tons. 



" 4, " " 10 " 35-00 16.32 " 



( dis. b. black, 162 lbs., ) 



" 3, " " chemicals ^ mur. of pot., 50 " > 5.00 13.56 " 



( sulp. of am., 38 " ; 



" 6, " " Stockbridge manure, 250 lbs., 5.00 8.13 " 



" 7, " " Bowker's H. and D., 250 lbs., 4.50 8.48 " 



" 8, no fertilizer of any kind 5-46 " 



In this series we see that the comparatively small amount of 

 fertilizer used on plot 3, costing only $5, gave a very credit- 

 able yield, even alongside of $17.50 worth of manure; and 

 that $10 per acre gave an increased crop of 8.10 tons, or a ton 

 at a cost of $1.23, but this is on the assumption that all of the 

 chemicals were used up last year, which will not prove to be 

 the case. 



