IOWA ACADEMY OF SCIENCES. 



65 



The excessive amount of free ammonia in deep well 

 water is accounted for by Fox* as follows. 



1. To entrance of rain water into well. 



2. To the beneficial transformation of harmful organic 

 matter into the harmless ammonia, through the agency of 

 sand, clay, and other substances, which act on the water in 

 a manner similar to the action on it of a good filter. 



3. To some salt of ammonia existing in the strata 

 through which the water rises; or, 



4. To the decomposition of nitrates in the pipes of the 

 well. Mr. H. Slater suggests that the agent concerned in 

 this reduction may, in the case of the deep well waters, be 

 the sulphide of iron which is found in the clay. 



Ammonia may be converted into nitrates and nitrites by 

 a process of oxidation, or be obtained from these salts by 

 one of reduction. We conclude, then, that the presence of 

 free ammonia in such comparatively large quantities in 

 these deep well waters is due to the reduction of nitrates and 

 nitrites by sulphide of iron, or some kinds of organic 

 matter, or some other agent, such oxidized nitrogen salts 

 having been produced in past ages by the oxidation of 

 organic matter." 



The State board of health standard limits the free 

 ammonia to .08 parts per million while the Michigan 

 Standard is .05 parts per million and if we attempt to apply 

 these standards we find that of the wells investigated only 

 Dubuque, McGregor No. 2, and the two Manchester will 

 meet the requirement of the two standards and Sabula 

 will meet, in addition to those named, the state limit for 

 free ammonia. 



The amount of albuminoid ammonia in the waters will 

 however meet the most exacting requirements. The only 

 exception is that of the Newton sample and this should be 

 investigated again before any definite conclusions are drawn 

 regarding the amount of albuminoid ammonia. If we ex- 

 cept this sample it is seen that the results vary from .068 

 parts per million to a trace. 



•Sanitary examinatious of water, air and food. Second Ed. p. 92. 



