Igo REVIEWS 
Mineral resources—The chief resources of the area include coal, 
limestone for the cement industry, sand and gravel, shale and clay, 
glass-sand, building stone, and water. Coal is of great importance, the 
region lying within the northern border of the eastern interior coal basin. 
While coal is present at several horizons in the Pennsylvanian, only the 
La Salle bed of the Carbondale formation is at present being mined. 
Workable deposits of clay and shale are confined to the Pennsylvanian 
and Quaternary deposits. Both are of some importance. The Lower 
Magnesian limestone formerly was extensively used as a source of 
natural cement and is still used to a small extent. One of the important 
industries of the region is the manufacture of Portland cement. The 
La Salle limestone is the chief source. The St. Peter sandstone is the 
chief source of building stone. Sand and gravel are abundant. While 
the structure is favorable, no evidence of the accumulation of oil and 
gas has been found other than the local subglacial pockets of gas which 
are in places utilized by private individuals. 
A. CIMeE: 
The Artesian Waters of North Eastern Illinois. By Caru B. 
ANDERSON. Illinois State Geological Survey, Bull. No. 34. 
IQIQ. 
The importance of this report lies in the partial dependence of 
the industries and cities of northeastern Illinois on artesian waters. 
Exclusive of Chicago, whose industries consume 30,000,000 gallons daily, 
the people of the region depend almost entirely on artesian waters. 
The area investigated includes thirteen counties. 
The bedrock comprises Cambrian, Ordovician, Silurian and Penn- 
sylvanian strata. It was found that while some water is obtained from 
all the systems named, the Potsdam sandstone is the best available 
source, a yield of 200 gallons per minute being common from flowing 
wells. For private consumption the shallower horizons are better. In 
general the water is hard. 
The method of treatment is by counties with more detailed dis- 
cussions for the different cities and villages. A large amount of useful 
data are compiled in the report, including water analyses, drilling costs, 
temperature of the water, and the position of the water table. 
A. C. McF. 
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