11. S. Tarr — Central Massachusetts Moraine. 148 



Ayer Junction, a distance of twenty-four miles I have had no 

 opportunity for studying the surface geology, but just southeast 

 of Ayer Junction distinct morainal deposits are found and a 

 quite continuous band of moraine extends from here westward 

 to the Connecticut river, passing south of Winchendon, Royal- 

 ston, Orange and Turner's Falls. This line of moraine is fifty 

 miles long and thus from Cape Ann to the Connecticut, a 

 distance of ninety-four miles, moraine has been found in 

 seventy miles, the remaining twenty-four not having been 

 examined. 



To briefly describe the Cape Ann moraine it may be said 

 that the essential features are sharp peaks and hummocks of 

 drift, completely enclosed kettle-holes of unstratified drift, and 

 a surface thickly strewn with bowlders chiefly of granite 

 locally derived. While the entire surface is bowlder strewn, 

 the most excessive development of bowldery deposits is in 

 trains, or parallel bands extending a little north of east at right 

 angles to the direction of glacial motion. There are several 

 square miles of such bowldery places on Cape Ann where the 

 bowlders are literally piled one upon another with rarely any 

 soil showing. A better development of the "bear-den" mo- 

 raine would be difficult to find. Parallel with these bowlder 

 lines are ridges of drift and the corresponding valleys. 



While the material composing the moraine is considerably 

 Jess clayey than ordinary till it is, with rare exception, an 

 unstratified deposit quite closely resembling till. A few 

 patches of stratified drift and a single serpent kame occur on 

 the island. 



On the mainland west of Cape Ann much the same charac- 

 ter marks the moraine, except that bowlders are less numerous, 

 as long as the moraine rests on the granite. Where it is found 

 upon the metamorphic rocks as in Wenham and westward the 

 bowlders decrease perceptibly in abundance and size, the de- 

 posits are more sandy and they merge more commonly into 

 stratified deposits. At the same time the distinctly "shoved" 

 moraine narrows. These facts are undoubtedly to be referred 

 in part to the change in character of supply, but chiefly to the 

 more moderate relief which permitted the deposition of sand 

 and gravel deposits. Some of the morainal peaks are partly 

 buried beneath such deposits. 



In the region between Ayer Junction and the Connecticut 

 River the morainal accumulations are quite puzzling. The 

 country is hilly and deeply scored by both east and west and 

 north and south valleys. The result has been a complicated 

 distribution of the morainal deposits which renders exact state- 

 ments concerning the detailed history of their formation quite 



