INTKODUCTOKY 17 



Calculated to Ibs. per acre on a basis of 31 inches 

 average annual rainfall, these results correspond to the 

 following quantities: 



Lbs. per acre. 



. 1-05 



1-68 1 2-94 



Nitrogen as organic matter 

 ammonia . 



,, nitric acid 



Chlorine as common salt 



0-21 

 25-37 



From analyses of the rain water collected at Eothamsted, 

 in Hertfordshire, the following results 1 were obtained as 

 the mean of observations extending over several years : 



Nitrogen as ammonia . 



,, nitrates and nitrites 



Organic nitrogen 

 Chlorine as common salt 

 Sulphuric acid . 



Lbs. per acre. 

 . 2-4} 

 . 1-0 4-4 

 . 1-0 ) 

 . 24-0 

 17-0 



The proportions of chlorides and sulphates in rain water 

 are extremely variable. They are always much greater 

 at the coast and in the neighbourhood of large towns than 

 in inland country places. The following quantities have 

 been observed : 



Warington, " Chemistry of the Farm.' 



S.M. 



