Artificial Manures for Swedes. 17 



The soot on analysis was found to contain 3 * 833 per cent, of 

 ammonia : it was procured at the rate of Qd. per bushel. 



It having been found on previous trials that it was quite 

 impossible to calculate the yield of each plot by weighing only 

 a small number of roots, the whole produce of each experimental 

 plot was weighed on a weigh-bridge. 



The following table exhibits the yield of each experimental 

 plot and the weight of the trimmed roots calculated per acre : 



Table showing the Produce of trimmed Swedes of Experimental Plots 

 of one-eighth of an Acre, and Weight of Crop per Acre. 



Per i of an Acre. Per Acre, 



tons. cwts. Ibs. tons. cwts. Ibs. 



Plot I. (Guano) yielded ... 1 9 7 11 12 56 

 ,, II. (Guano and dissolved coprolites) 



yielded 1 12 2 12 16 16 



,, III. (Bone-dust) ... 120 8 16 



IV. (Bone superphosphate) 

 V. (Economical manure) 

 VI. (Nut-refuse) . . . 

 VII. (Dissolved coprolites) 

 VIII. (Nothing) 



1 14 2 13 12 16 



15 2 6 16 



150 10 



190 11 12 



13 540 



IX. (Commercial dried night-soil) 130 940 

 X. (Mixture of soot, guano, dis- 

 solved coprolites, and bone- 

 superphosphate) . ,, 151 10 8 



The results obtained in these experimental trials are both 

 interesting in a practical and scientific point of view, and I may 

 therefore be allowed to offer a few remarks which are suggested 

 by them. Before doing this, however, a point of some moment 

 demands special notice. It will be observed that the unmanured 

 portion of the experimental field only gave a produce of 5 tons 

 4 cwts. per acre. The natural inference which may perhaps be 

 drawn from so small a crop is, that the land was not in a proper 

 state of preparation for the turnip-crop, and that, consequently, 

 all the experiments are not to be depended upon ; I have shown, 

 however, by the mechanical analysis of the soil on which the 

 experiments were tried, that it was well pulverized, and have 

 been assured moreover by our farm-manager, that the experi- 

 mental field was in a fit state of preparation for the swedes. 

 The soil, it is true, was naturally poor, shallow, and rested on 

 lime-stone rock, from which it was separated by a clayey subsoil 

 of inconsiderable depth. But far from considering this circum- 

 stance as being calculated to vitiate the results of the trials, there 

 is much reason to believe that a soil of such a description is 

 peculiarly well adapted for the making of experiments from 

 which legitimate and trustworthy inferences may be derived. 

 A poor soil, it strikes me, is much better adapted to bring out 

 the full manurial effect of different fertilizers than land in the 



