144 jR. S. Tarr — Central Massachusetts Moraine. 



impossible at present. The distribution is in more or less con- 

 tinuous patches; but distinct lines of moraine cannot be traced 

 for any considerable distance, their continuity being inter- 

 rupted by the irregularity of the topography. As the result of 

 this we find a series of scalloped, serrated lines in the general 

 moraine. These lines and the entire moraine are sometimes 

 broken, yet the general continuity of the deposit is undoubted, 

 for the breaks are rarely a mile in length. 



A vacillating condition at this place is indicated by the 

 great width of the morainal deposits. The moraine-covered 

 tract is often eight or ten miles in width and isolated patches 

 of "shoved" moraine are found both to the north and south 

 of this. 



The central Massachusetts moraine is typically developed at 

 Winchendon, Gardner, and south of Athol and Orange on the 

 Winchendon and Warwick sheets of the Massachusetts topo- 

 graphical map. A detailed description of the moraine on the 

 various sheets will be found in Prof. Shaler's forthcoming 

 monograph on the Surface Geology of Massachusetts. It pre- 

 sents all the features of a typical " shoved " moraine, being 

 rough in outline and bowlder strewn, having hummocks and 

 kettles of unstratified drift and being associated with stratified 

 drift both of contemporaneous and subsequent origin. This 

 stratified drift is of the sand plain, esker and valley drift types. 

 In places the morainal hummocks are made up of roughly 

 stratified layers of till and gravel, they are at times partly and 

 even entirely covered by stratified drift of the overwash type, 

 and sand plains are not uncommonly found amid the morainal 

 peaks and kettles. No distinct frontal apron exists, for the 

 diversity of the topography would not admit of such well de- 

 fined level deposits. 



These observations prove that the ice halted in its retreat 

 from New England at about the line occupied by this moraine. 

 The halt was not of sufficient duration to permit of the forma- 

 tion of a strikingly well defined moraine yet it was long 

 enough for the formation of a well defined morainal band. 

 The varying width in the central part of the State points to 

 some vacillation in the ice front at this place, though this does 

 not seem to have been the case in the eastern part of the 

 moraine near the coast line. 



One of the striking features of the central Massachusetts 

 moraine is its east and west course, since its linear extension is 

 in general direction slightly diagonal to the glacial striae. This 

 is particularly the case in its sea coast end where it can be 

 traced continuously for a score of miles nearly due west, 

 whereas the striae point usually N. 25 W. or even more. Even 



