216 GEOLOGY OF ILLINOIS. 



uninteresting. Its detailed report will consequently be short and some- 

 what unsatisfactory. Such counties as LaSalle, and others in that part 

 of the State, afford the geologist a more interesting field for observa- 

 tion.* 



Economical Geology. Although underlaid by the Coal Measures, coal 

 in workable quantities has not yet been discovered in the county. In 

 the north-western and south-western portions, coal seams may exist, 

 but their character and extent remain to be proved, but it is likely that 

 valuable beds will yet be discovered. The same might also be said of 

 stone suitable for the purposes of building or other economical uses. 

 The stone quarries, if any good ones exist, lie concealed beneath the 

 surface, and have not yet been opened. Lime, as a natural conse- 

 quence, is not burned to an extent that would make it a valuable pro- 

 duction. The railroad and river facilities for transportation will always 

 enable the citizens of this county to obtain coal, stone, and lime from 

 other places with very great ease. Sands and ordinary clays exist in 

 great abundance. Materials for the manufacture of common red brick 

 can be found in most parts of the county, and in the valley of the Il- 

 linois river these materials are of excellent quality. For agricultural 

 purposes, fruit-raising, and wine-growing, this county is very similar to 

 Marshall county. 



* NOTE. The hard, blue limestone which forms the upper bed of the Coal Measures at Sparland, I 

 have no doubt is the same bed outcropping at Jones' Prairie, and at Lonsdale's Quarries, in Peoria 

 county, and usually lies about fifty feet above coal No. 7, and from ninety to one hundred feet above 

 coal No. 6, and one hundred and fifty feet above coal No. 4. As this limestone is mentioned by Mr. 

 SHAW as outcropping in the bluffs of the Illinois, in this county, it may serve as a guide to those in 

 search of coal ; and it will indicate the depth to which it would be necessary to go in the vicinity of 

 its outcrop, to reach either or all of the above named coals. It is probably the same as the limestone 

 No. 32, in the general section of the Coal Measures of LaSalle county, given on page 265, in Vol. Ill 

 of these reports. A. H. W. 



