actiojst of the atmosphere 



155 



In nearly every case, however, the percentage of ammonia, as 

 determined, equalled or exceeded the amount necessary to com- 

 bine with the acid, forming thus ammonium nitrate. Failyer^s 

 researches in Kansas, carried on for a period of four years, 

 during which time water was collected from 266 rainfalls, 

 showed in but seven instances nitric acid equalling or ex- 

 ceeding the ammonia. In all other reported cases the amount 

 is less, with the possible exception of a fall of hail at Nismes, in 

 1845, which is stated to have been sufficiently acid to be sour 

 to the taste. As direct promoters of rock decomposition, neither 

 atmospheric nitrogen nor free nitrie acid need, then, very seri- 

 ous attention. The following tables are, however, of interest, 

 the first being abridged from Johnson's How Crops Feed, and 

 the second from Professor Failyer's paper above quoted. 



Amounts of eain and op ammonia, nitrio acid, and total nitrogen 

 therein, collected at eothamstedd, england, in the years 1855-56, 



CALCULATED PER ACRE, ACCORDING TO MESSRS. LaWES, GILBERT, AND WaY. 





Quantity of rain in 



Imperial gallons. 



1 gal. = 10 lb, water 



Ammonia 

 (in pounds) 



Nitric Acid 

 (In pounds) 



Total Nitrogen 

 (in pounds) 



Total . . 



1855 

 663.332 



1856 



616.051 



1855 



7.11 



1856 



9.53 



1856 



2.98 



1856 



2.80 



1855 



6.63 



1856 

 8.31 



Amounts of rain and of ammonia, nitric acid, and nitrogen therein, 

 collected at manhattan, kansas, 1887-90, according to gr. h. 

 Pailyer. 



Parts per million of water 

 Grammes per acre . . . 

 Pounds per acre . . . 



Total IsTitrogen. 



Means for 4 



years 



0.522 

 1563.0 

 3.44 



Nitrogen in 



ammonia. 



Means for 8 



years 



.388 

 1196.0 

 2.63 



Nitrogen in 



nitric acid. 



Means for 3 



years 



0.166 

 480.0 

 1.06 



It has been demonstrated, however, that nitrogen compounds 

 and nitrogenous matter in the soil may become subject to nitri- 

 fication through the action of bacteria, whereby ammonia, 

 nitrous or nitric acid, carbon dioxide, and water are formed, 

 though, as Wiley says, *' The ammonia and nitrous acid may 



