0)1 Agricultural Chemistry. 



15 



2 cwts. of sulpliate of ammonia, with no direct mineral manure in 

 either case since the first season of 1844, were in this, the fourth 

 season, set apart for the trial of some substance rich in carhon (but 

 not so either in nitrogen or in mineral matter), by the side of pure 

 nitrogenous supply. Thus one half of 9a (9a^) was manured 

 with ground rice, at the rate of 1 ton to the acre. The other half 

 of 9a (9a') had 150 lbs. of sulphate and 150 lbs, of muriate of 

 ammonia ; as also had 96. The effect of the 1 ton of rice is to 

 give 224 bushels of dressed corn, or only 6 bushels more than the 

 unmanured plot ; whilst the ammoniacal salts of 9a^ and 95 gave 

 respectively 26l and 26 bushels. That is to say, with a differ- 

 ence of only half a bushel in the two cases with ammoniacal salts, 

 an average is obtained of 9i bushels more than on the unmanured 

 plot. 



It surely is needless to attempt further to justify, by the results 

 of individual years, our assertion^ that in practical agriculture 

 nitrogenous manures are peculiarly adapted to the growth of wheat. 

 We shall therefore conclude this part of our subject by directing 

 attention to the history of a few of the plots throughout the entire 

 series of years up to the present time, as compared with that of 

 the unmanured plot during the same period. 



The six next tables which follow (numbered V. to X. inclusive) 

 give the results of 6 of the plots thus compared vv^ith the unma- 

 nured one; and in Table XI. we have the results of all those plots 

 brought together in one view. 



Table V. 



