182 SUGGESTIONS FOR NEW EXPERIMENTS 



Increase. 



No application . yielded 26^ cwt. of hay. 



Nitrate of soda, 1^ cwt. ... 37 ... 10J cwt. 



Nitrate of soda, 2 cwt. ... 64 27 ... 



If the field was uniform in quality and natural productive- 

 ness, these results indicate a much larger proportional increase 

 from the additional half cwt. in the second experiment, than 

 from the 1J cwt. in the first. Is such a result likely often to 

 follow from such additional doses of fertilising substances ? 



2. Mr Kuhlmann, in 1843, applied to old grass-land in the 

 neighbourhood of Lille, in French Flanders, nitrate of soda in 

 the proportions of 133 and 266 kilogrammes per hectare respec- 

 tively, with the following results per hectare : 



Increase. 



No application . gave 4000 kilos, of hay. 



Nitrate of soda, 133 kilos., ... 4800 ... 800 kilos. 



Nitrate of soda, 266 5725 ... 1725 ... 



In this case the increase of produce was nearly in proportion 

 to the quantity of nitrate applied 133 kilogrammes causing an 

 increase of 800, and 266 kilogrammes an increase of 1725 kilo- 

 grammes of dry hay. 



These experiments give rise to various questions, such as 

 to what extent can the increase in the doses of a manuring 

 substance be profitably carried ? on what crops will the larger 

 doses be most economically applied ? on what soils will they 

 be most successful ? To solve these questions, further experi- 

 ments are to be desired. 



5. Suggestions for new experiments with the nitrates of 

 potash, soda, lime, and magnesia. 



I offer the following suggestions for further experiments 

 with these nitrates : 



1. The effect of each or any of these nitrates, applied alone 

 as a top-dressing to corn-crops, or as an application to root- 

 crops after they are above the ground. Especially, their effects 

 upon wheat and barley, and upon beets, turnips, and cabbage, 

 ought to be accurately noted. 



