12 On Agricultw^al Chemistry. 



Table III. 



Harvest 1846. Selected Results. (See third section of diagram I., 

 opposite p. 14.) 



Description and Quantities of the Manures per Acre. 



Dressed Corn 

 per Acre, 

 in Buihels 

 and Pecks. 



Total 

 Corn 

 per Acre, 

 in lbs. 



Straw 

 per Acre,, 

 in lbs. 







Section 1. 



bush, pecks. 



lbs. 



lbs. 



Plot 3. No manure ..... 

 5, 2. 1-i tons of farm-yard manure . . 



17 3| 

 27 Of 



1207 

 1826 



1513 

 2454 



Section 2. 









10&. No manure ..... 

 10a. Sulphate of ammonia 224 lbs. 



17 21 

 27 \l 



1216 

 1850 



1455 

 2244 



Section 3. 









, , 5<i'. Ash of 3 loads of wheat straw • • 

 , , 5a% Ash of 3 loads of wheat straw, and to})- j 

 dressed with 224 lbs. of sulphate of[ 

 ammonia . . . . .J 



19 0^ 

 27 0 





1541 



2309. 



Section 4, 









6a. Lleblg's wheat manure 448 lbs. . . 

 , , 66. Liebig's wheat manure 448 lbs., with j 

 112 lbs. each of sulphate and muriate) 

 of ammonia . . . . .] 



20 li 



29 Of 



1400 

 1967 



1676 

 2571 



At this third experimental harvest we have on the continuously 

 unmanured plot, namely, No. 3, not quite 18 bushels of dressed 

 corn, as the normal produce of the season ; and by its side we 

 have on plot 10^, — comprising one-half of the plot 10 of the pre- 

 vious years, and so highly manured by ammoniacal salts in 1845, 

 but now unmanured, — -rather more than 17^- bushels. The near 

 approach, again, to identity of result from the two unmanured 

 plots, at once gives confidence in the accuracy of the experiments, 

 and shows us how etFectually the preceding crop had, in a prac- 

 tical point of view, reduced the plots, previously so differently cir- 

 cumstanced both as to manure and produce, to something like an 

 uniform standard as regards their grain-producing qualities. We 

 take this opportunity of particularly calling attention to these 

 coincidences in the amount of produce in the two unmanured 

 plots of the different years, because it has been objected against 

 our experiments, as already published, that confirmation was 

 wanting as to the natural yield of soil and season. 



Plot 2 has, as before, 14 tons of farm-yard manure, and the 

 produce is 27i bushels, or between 9 and 10 bushels more than 

 without manure of any kind. 



On plot lOfl, which in the previous year gave by ammoniacal 



