IOWA ACADEMY OF SCIENCES. 109 



the Ordovician. The water contains twenty to twenty-five 

 per cent less of calcium and magnesium carbonates than 

 the other waters examined. This may result from an 

 artesian character of the well, the water coming from 

 sandstones underneath the Niagara; or a small adjacent 

 stream may find its way into the well through fissures in 

 the rock. Several analyses showing a varying amount of 

 free and albuminoid ammonia may incline rather to the 

 latter alternative. The analysis was made in May, 1900, 

 by Miss Herrinton. 



Total solids ',86 6 



CaCOa 154.9 



MgCOs 07 



Si02 23.00 



FesUs and AhOs 80 



NaCl and KCl 24.00 



COs free and partly united 114.00 



CaS04 4 08 



Nitrates 1 38 



Free ammonia 084 



Albuminoid ammonia 0.032 



(). The Cedar Biver. The sample was taken from the 

 river at Ivanhoe bridge, May, 1900; analyzed by Mr. 

 Rayner. 



Total solids 234 2 



CaCOs. 147 1 



MgCOs -,7.5 



SiOe 2 



Fe203 and AI2O3 2.2 



NaCl and KCl 20 



CO2 free and partly united 80.0 



CaS04 5.1 



Nitrates 0.77 



Free ammonia 0.12 



Albuminoid ammonia 0.27 



In all the waters examined the ratio of magnesium car- 

 bonate to calcium carbonate is about one to two with the 

 exception of Mr. Young's water where the ratio is one to 

 three. 



We desire to thank Professor W. H. Norton for valuable 

 suggestions in connection with these investigations. 



