STATE GEOLOGIST. 2f3 



ing water, while at the Observatory, which is 42 feet higher, 

 the water rises within six feet of tho surface. The latter well 

 is obviously supplied from a local basin which occupies a higher 

 level. 



The purity and salubrity of well and spring water, in the 

 Lower Peninsula of Michigan, are generally very great. An 

 analysis of the water from the well on the north side of the 

 University campus, was made by T. C. McNeill, A. B., of tho 

 Laboratory of Applied Chemistry, with the following result: 

 Depth of well, 70 feet 8 inches. 

 Temperature of water, 50 c ' Fall. 

 Free carbonic acid in 100 parts, .015598. 



Solid constituents: 



Carbonate of lime, 0.01 7800 



Carbonate of magnesia, . 006058 



Carbonate of iron, . 000290 



Chlorid of sodium, 0.0' 0448 



Sulphate of soda 0.000507 



Carbonate of soda . 000 1 53 



Sulphate of potash . 00067a 



Silicic acid O.0U073O 



Organic matter, . 002300 



Total, . 028963 



The wells of Detroit, and much of the region along the lake 



and river shore, from Toledo to St. Clair, are sunk in lacustrine 



deposites, which impart a greater per centage of organic and 



soluble matter. The following analysis was made by Prof. S. 



H. Douglass, in 1854, for the Board of Water Commissioners of. 



the city of Detroit. The water was taken from a well at tho 



residence of Amos T. Hall, on Woodward Avenue: 



Chloi id of potassium, . 011 000 



Chlorid of sodium 0.072f 20 



Chlorid of magnesium, . 034760 



Sulphate of potassa 0.010450 



Sulphate of lime, 0.028260 



Silica . 002370 



Carbonate of lime, . 039 1 90 



Carbonate of iron, . 001 020 



Total, '. 0. 199570' 



