RECESSIONAL ICE BORDERS IN BERKSHIRE, MASS. 359 



burg, and Somerset to a point about three miles northeast of the 

 northeast corner of the Taconic quadrangle, where No. i6 is 

 found, about four miles south of Grout's mill. 



Among these branching and interlacing series of terminal 

 deposits there are several courses by which a complete series 

 may be followed continuously across the county and across the 

 two quadrangles from southeast to northwest. The Farmington- 

 Housatonic-Hoosic series covers the whole interval, and shows 

 that between the southeast and northwest corners of the county 

 the ice-front haked fourteen times, while in crossing the two 

 quadrangles it halted twenty or twenty-one times, the uncertainty 

 depending on the unfinished work at the northwest corner of the 

 Taconic quadrangle. 



Along the west side of the two quadrangles on the less 

 rugged slope to the Hudson the recessional moraines can readily 

 be traced as continuous individuals. They run here in lines 

 more nearly straight, the border drainage was strong, and the 

 series as a whole can be made out with a completeness not pos- 

 sible within the limits of Berkshire county. However, so far as 

 the several interlacing series of fragments in the mountain val- 

 leys are complete, they may be regarded as safe counters for 

 the enumeration of the recessional series, and if, as assumed 

 above, the several ice-borders of the recession are separate and 

 distinct individuals without overlappings, then the series may be 

 regarded as complete, provided there have been no errors or 

 omissions in observation. In order that there might be the 

 least possible chance of such errors or omissions, the counts 

 have been confined as far as possible to the valley deposits ; for 

 in Berkshire county the morainic deposits are concentrated in 

 the valleys and are nearly always more strongly developed there 

 than elsewhere. A series of terminal deposits like any of the 

 stronger ones mentioned above is in fact a series of accentuated 

 points in the recessional moraines. When series do not follow 

 valleys, but cross hills and mountain ridges, they are not by 

 themselves so reliable. Such in part are the two lines from 

 Colebrook and New Boston to Van Deusenville. But where they 

 occur as supplementary lines between clearly defined valley 

 series they may have considerable corroberative value. 



