LARGE GLACIAL BOWLDERS 



GEORGE D. HUBBARD 

 Oberlin College 



Mention of large glacial bowlders is not uncommon. In fact 

 most localities glaciated have their " largest in the state." Some 

 lie so as to reveal easily the fact that they have been transported. 

 Others are more or less concealed, and some care is needed to 

 determine whether the rock is really a transported mass or country 

 rock in place. 



A mass of limestone in Ohio covering about three-quarters of 

 an acre, and in places sixteen feet or more in thickness, was men- 

 tioned by Orton in one of the older reports of Ohio geology and 

 cited by Dana. 1 In the Alps was found a mass containing about 

 200,000 cubic feet of rock or enough to cover a fourth of an acre 

 twenty feet deep. 2 Sardeson 3 reports a block of limestone moved 

 a short distance whose width was over 100 feet, thickness several 

 feet, and length unknown. Limestone bowlders, often large 

 masses, are quite common in parts of Illinois, specifically in western 

 Livingston County, in northern McLean, and in parts of Cham- 

 paign, Ford, and Vermilion counties. Following is a detailed 

 description of several masses or " pockets" of this rock which have 

 been studied. 



On the south side of the Champaign-Ford county line one and 

 one-half miles east of the northwest corner of Ludlow township 

 are the remains of a large " pocket." H. Ff. Atwood of Paxton 

 who owns the farm says several loads of the rock have been drawn 

 away for building purposes, but enough remains to mark the place 

 distinctly. 



Near Saybrook, McLean County, are a number of localities 

 where limestone is found at the surface. On the farm of Mr. Riggs, 



1 J. D. Dana, Manual of Geology, 5th ed. (1895), 960. 



2 Ibid., 248. 



3 Jour. Geol. (1905), XIII, 351-57. 



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