201 



TABLE II. EFFECT OF LIME UPON ROTHAMSTED GRASS PLOTS. 



Relative yield of hay on the limed portions, the unlimed part 

 being taken as 100. 



(1) 400 Ibs per acre 448 kgs. per hectare. 



(2) 600 Ibs per acre = 672 kgs. per hectare. 



Another example of these secondary actions between fertilizers 

 and the soil which are not immediately apparent is afforded by 

 nitrate of soda. 



All farmers upon clay have recognized that the use of nitrate 

 of soda leaves the land very wet and sticky. 



Mechanical analyses were made of the soils, and it was sur- 

 prising to find that the nitrated soils were, contrary to expectation, 

 distinctly and regularly coarser, by the loss of some of their finer 

 particles, instead ot having undergone a disintegration accompanied 

 by a greater production of these. 



Table III gives the average mechanical analyses of five pairs 

 of plots from the different Rothamsted fields ; in each pair there 

 was a plot receiving nitrate of soda and one ammonium salts. 



TABLE III. PERCENTAGES AFTER IGNITION. 



