COMBINED NITROCxEN IN KAIN 1<» 



since September 188G (for the first few montlis by Scliloesing's 

 method, antl subsequently by Williams' zinc-copper couple 

 method). 



In addition to the analyses of monthly samples of rain, a 

 large number of single samples have been analysed at 

 Rothamsted, as well as about eighty samples by the late Sir 

 E. Frankland.* 



Table VI I. — Nitrogen and Chlorine in Ilothamstcd Rain. Munfhly 

 Averages, 15 years (1889-1903). 



It will be convenient, for the purpose of sunimari.sing the 

 results relating to nitrogen, to confine attention to the fifteen 

 years 1889-1003, as during that period regular determinations 

 both of ammonia and nitrates are availa])le. 



In Table VII. will 1)0 found the average monthly I'ainfall 

 for the period in question, the amount of nitrogen as ammonia 

 and as nitrate (or nitrite), also the chlorine, all expressed both 



* See the Sixth Report of the Rivers Pollution Commission, 1874. 



