S. W. Johnson on Nitrification. 239 
ate of potash with garden soil prevents nitrification and 
causes the development of ammonia. (Agronomie, etc., 11, 
excess of active oxygen ; the precess was therefore a putrefac- 
and fire, every decaying plant and animal, the organic matters 
tile oils of cone-bearing trees, are indirectly, means of convert- 
mg a portion of free a a into nitrous and nitric acids, or 
ammonia, : 
