MAIN MORAINIC SYSTEM OF THE SCIOTO LOBE. 421 



importance because of their bearing on the question of changes of ice 

 currents. Newberry reports "huge bowlders of Corniferous Kmestone" in 

 Northampton Townsliip, Summit County, which he thinks have been brought 

 from the islands in Lake Erie.^ If so, the early ice movements across these 

 islands must have been southeastward — a very different course from that of 

 the later movements. Bowlders of the same class were reported to the 

 writer from Talmadge Township (which is southeast of Northampton), but 

 they were long ago burned for lime. The source of these bowlders should 

 be more conclusively demonstrated before inferences are drawn as to 

 changes of ice currents. 



It has been reported by Whittlesey that copper occurs in the drift as 

 far east as Weymouth, Medina County, Ohio.^ 



Bowlders of red, jaspery conglomerate, thought to be from the Huronian 

 rocks north of Georgian Bay, are not rare in the vicinity of Mansiield 

 and northward from there to Norwalk and Brownhelm, and they are 

 occasionally found still farther east, one being reported near Andover, Ohio. 

 They are quite common in western Ohio, northern Kentucky, and Indiana, 

 and a few have been found as far west as southeastern Iowa. Those near 

 the eastern limit of their known distribution indicate a transportation in a 

 direction slightly east of south, though their main distribution appears to 

 have been west of south. Chamberlin and Salisbury have cited the 

 following evidences of southward movement into Ohio from the Htiron 

 Basin : 



To the east of the Lake Michigan trough lay the capacious vallej- of Lake 

 Huron, flanked by Georgian Bay. There is strong evidence that these valleys 

 directed these glacial streams southward in the retiring stages of glaciation, at least, 

 and presumably at all stages. This is shown both b}^ striation and by transportation. 

 Copper, presumed to come from the Lake Superior region, has been found in eastern 

 Michigan and even in Ohio. In the I'emarkable bowlder belt of Logan, Champaign, 

 Miami, Montgomery, and Preble counties, Ohio, and Wayne and Randoijih counties, 

 Ind., are numerous peculiar greenish quartzite bowlders not common to the general 

 drift. Professor Irving has identified specimens of these as derivations from certain 

 quartzites of the typical Huronian region north of Lake Huron, samples in his col- 

 lection being indistinguishable from the erratics collected bj- one of us. While it is 

 possible that both the native copper and these quartzites ma}' have had an origin 

 farther eastward, these instances, taken in connection with a wider class of evidence, 



1 Geology of Ohio, Vol. I, 1873, p. 206. 



^Smithsonian Contributiona, 18g6, On Fresh Water Glacial Drift, etc., p. 11. 



