EFFECTS OF NITRATE OF SODA ON BARLEY AND OATS. 177 



of nitrate of soda, 165 Ib. of the nitrate of potash ought to have 

 been used. The above result, therefore, even had it been in 

 duplicate, is not so decisive as at first sight it appears to be^ 

 The absolute effect of each, it is obvious, could only have been 

 brought out by a comparison of their effects with the produce of 

 other portions of the field to which nothing had been applied. 



b In 1843, Mr Finnic, at Swanston, Mid-Lothian, obtained 

 the following results from four experimental plots of barley : 



Grain. Straw. 



Nothing gave . . 49 bush. 1 35 stones 



Nitrate of potash, 47 Ib. . 50 ... 154 ... 



Nitrate of soda, 123 Ib. . 60 ... 201 ... 



Common salt, 6 J cwt. . 50 ... 151 ... 



This experiment would also seem to imply that the nitrate of 

 soda is more useful than the nitrate of potash to the barley crop. 

 But the equivalent weights of the two nitrates are 107 for that 

 of soda, and 127 for that of potash. To produce an equal effect 

 with the 123 Ib. of nitrate of soda, therefore, 146 Ib. of saltpetre 

 ought to have been applied, whereas the quantity laid on was 

 only 47 Ib., which produced no sensible effects. This compara- 

 tive experiment, like the former, leaves the matter in doubt, 

 and only shows the necessity of new and more carefully con- 

 ducted trials. 



3. Experiments on oats. 



a By Mr Main, Mid-Lothian, Scotland, in 1846, on oats 

 after turnips 



Grain. Straw. Weight per bushel. 



Nothing gave . . 45 bush. 24 cwt. 40 Ib. 

 Nitrate of soda, 2 cwt. . 45 ... 21 ... 38^... 



In this experiment the application seems actually to have 

 diminished the produce both of grain and of straw. 



b Mr Finnic, Swanston, Mid -Lothian, (Blainslie oats), in 

 1843- 



Grain. Straw. Weight per bushel. 



Nothing gave . . 48 bush. 142 stones 42^ Ib. 

 Nitrate of soda, 123 Ib. 60f ... 225 ... 42^... 



Common salt, 6^ cwt. 55^ ... 166 ... 421... 



In this experiment the nitrate of soda was very successful in 

 increasing the quantity both of grain and of straw, without 



M 



