Diluvium. 



155 



In the valley of the Connecticut, we meet with abundant traces of 

 a diluvial current from the north. Thus, the diluvium which covers 

 the red sandstone in the south part of Bernadston, and the north part 

 of Gilt and Greenfield, is composed almost entirely of detritus from 

 the granite, argillaceous slate, and quartz rock, lying a few miles 

 north. In Amherst, the diluvial pebbles and bowlders are granite, 

 gneiss, hornblende slate, and red sandstone conglomerate ; corres- 

 ponding precisely with similar rocks in place in Leverett and Sun- 

 derland, six or seven miles north. But probably a fluvialist would 

 regard all marks of this kind in the Connecticut valley, as having 

 resulted from the action of the river when its barriers were yet un- 

 broken below Northampton and Middletown. And this explanation 

 would probably satisfy the mind, were it not for the evidence already 

 exhibited, that the Connecticut could never have been more than 100 

 or 200 feet above its present level : an elevation not sufficient to pro- 

 duce the diluvium that has been described. 



Another class of facts is still more inexplicable on the fluviatile 

 hypothesis. On the east side of the greenstone and sandstone range, 

 which passes through the west part of West Springfield, and which 

 rises into Mount Tom in East Hampton, we find mixed with the 

 bowlders of sandstone and greenstone, many others of a peculiar 

 sienitic granite, which occurs in place, on the west side of the range 

 above mentioned, in Northampton, Hatfield, and Whately. These 

 must have been driven over the greenstone ridge by a northerly cur- 

 rent : and yet, some of them are two or three feet in diameter, and 

 the ridge is several hundred feet high. As we go northerly, still 

 continuing on the east side of the greenstone, the number and size 

 of these bowlders increase. We find them even upon the summit of 

 Mount Tom ; though as we ascend this precipitous peak, their num- 

 ber and size diminish ; so that on the top, I never saw one more 

 than six or eight inches in diameter. Now this mountain rises 

 nearly a thousand feet above the plain w r hich lies to the northwest ; 

 and on that side it presents a mural face several hundred feet high. 

 Yet these bowlders must somehow have been forced up this precipice ; 

 since the bed from which they originated lies in a northerly direc- 

 tion from the mountain. 



On the banks of the Westfield or Agawam river, in the west part 

 of West Springfield, I found small bowlders of quartz, containing 

 galena and blende. Both the matrix and the ores correspond exactly 

 with those found in Southampton, Williamsburgh, and Whately. All 



