10 On Agricultural Chemistry. 



Table II. 



Harvest 1845. Selected Results. (See second section of diagram I., 

 opposite p. 14.) 



Description and Quantities of the Manures per Acre. 



Dressed Corn 

 per Acre, 

 in Bushels 

 and Pecks. 



Total 

 Corn 

 per Acre, 

 in lbs. 



Straw 

 per Acre, 

 in lbs. 



Section 1. 

 , , 2. 14 tons of farm-yard manure . 



bush, pecks. 

 32 01 



lbs. 



1441 

 1967 



lbs. 



2712 

 3915 , 



Section 2. 



, , 5(2. No manure . . • . • 

 , , 56. Top-dressed with 252 lbs. of carbonate 1 

 ammonia (dissolved), at 3 times, dur-/ 

 ing the spring , . . .J 



26 3| 



1732 



9ft«4 



3599 



Section 3. 









q (Sulphate of ammonia 168 lbs. 1 top-dressed) 

 " '* (Muriate of ammonia IBSlbs.) at once j 

 jQ (Sulphate of ammonia 168 lbs. Hop-dressed | 

 ' ' ' (Muriate of ammonia 168 Ibs.j at 4 times j 



33 11 

 31 31 



2131 

 1980 



4053 

 4266 



with superphosphate of lime), and which is now, also, without 

 manure, gives rather more than 22J bushels of dressed corn, the 

 correctness of the result of plot 3, the permanently unmanured 

 plot, is thereby fully confirmed. 



This plot No. 5, previously two-thirds of an acre, was, in this 

 second year, divided into two equal portions ; one of these (•' plot 

 5a") being, as just said, unmanured, and the other ("plot 5Z> ") 

 having supplied to it in solution, by top-dressings during the 

 spring, the medicinal carbonate of ammonia, at the rate of 250 lbs. 

 per acre : and it is seen that we have, by this pure but highly 

 volatile ammoniacal salt alone, the produce raised from 22^ 

 bushels to very nearly 27 bushels! 



In the next section of the table are given the results of plots 9 

 and 10, the former of which had in the previous year been manured 

 by superphosphate of lime and a small quantity of sulphate of 

 ammonia, and the latter by superphosphate of lime and silicate 

 of potass. To each of these plots H cwt. of sulphate and 



cwt. of muriate of ammonia were now supplied. Upon plot 9 

 the whole of the manure was top-dressed, at once, early in the 

 spring; but on plot 10 the salts were put on at four successive 

 periods. The produce obtained by these salts of ammonia alone 

 is 33 bushels and three-eighths, when sown all at once, and nearly 

 32 bushels when sown at four different times — quantities which 

 amount to about 10 bushels per acre more than was obtained 



