PROBABLE HISTORY OF THE BOULDERS 751 



rived from that hill. But on this point it may be said that the bowlders 

 south of Qiieechy Lake, being of the same character, suggest the begin- 

 ning of a train leading southward, and occasional bowlders of the same 

 kind occur between State Line and Great Barrington, both in the valley 

 of Seekonk Brook and of Williams Eiver, farther east, although par- 

 ticular search for them has not been made in this interval. 



It is, of course, possible that the Great Barrington bowlders were de- 

 rived from some other nearer source than Fryes Hill, but no other out- 

 crop of amphibolite schist is known in the region north and northwest of 

 Great Barrington. Smaller bowlders of the same rock in the same condi- 

 tion were found occasionally on a line running south-southeast from 

 Great Barrington nearly to the south line of Massachusetts. Several 

 were found where this line crosses Konkapot Valley 2 or 3 miles south 

 of Mill Eiver. Two or three small bowlders of this same rock were found 

 about 3 miles south of Tolland, Massachusetts. The latter seem likely to 

 belong to the Eichmond train, for they lie in line of its trend produced. 



Amphibolite schist occu.rs also on Haystack Mountain north of Nor- 

 folk, Connecticut, and at points from 1 to 3 miles farther north, but 

 none of the bowlders mentioned, neither those in the Konkapot Valley, 

 north of Haystack Mountain, nor those south of Tolland, can be sup- 

 posed to come from these outcrops by glacial transportation, for the 

 trend of the ice movement was toward this mountain from Konkapot 

 Valley, and they would have to be carried 10 miles a little north of east 

 to reach the locality south of Tolland. 



Probable History of Bow^lders of the Great Barrington Train 



The rounded, weathered condition of all the bowlders of the Great 

 Barrington train bespeaks a very different history from that of the Eich- 

 mond train. The Eichmond blocks appear to have been plucked from 

 the summit of Fryes Hill by the last ice-sheet, carried on or in the upper 

 part of the ice and strewn across the country on the line of ice move- 

 ment. They appear to have been deposited or let down on the surface. 

 The Great Barrington bowlders, on the other hand, are water worn and 

 weathered and more intimately associated with the till, as if they had 

 been transported in the dirt-laden basal part of the ice. 



These bowlders were in all probability detached from Fryes Hill in 

 preglacial or interglacial times and were water worn and weathered 

 before the coming of the Wisconsin ice-sheet. These characteristics must 

 have been acquired by them before they were finally incorporated into 

 the drift and deposited where they are now found. 



