332 GEOLOGY OF OLD HAMPSHIRE COUNTY, MASS. 



He will then find the texture of the rock to be tiuer, and in some instances 

 it contains a portion of hornblende, while the proportion of quartz is dimin- 

 ished somewhat and the feldspar frequently becomes red. Coming- nearer 

 Northampton, however, we find the hornblende more and more abundant 

 until we arrive at the eastern edge of the range, where we find a rock 

 containing little else than feldspar and liornblende." 



lie notes the abundant veins of granite in the brook 2 miles south of 

 the church in Whately, and the many minute faults of the rock and its 

 peculiar conglomerated character. "The rock here contains numerous 

 embedded masses of other primitive rocks, as gneiss, mica-slate, quartz, 

 liornblende, and a finer kind of syenite, all almost uniforndy rounded." 



He mentions a third locality of syenite west of the road, a mile north 

 of the village of Whately, associated with "greenstone-slate nearly allied 

 to hornblende-slate, and unstratified primitive greenstone. It consists of 

 nearly equal jiroportions of feldspar and hornblende — the former white 

 and compact or very finely granular, entirely destitute of foliated structure 

 or pearly luster."^ A study of this rock in tliin section shows it to be an 

 amphibolite. The white spots of supposed feldspar are parts of the finely 

 granular ground mass, which are free from green hornblende, and it is not 

 diff'erent from the other beds of amphibolite nnmed abo^•e, with which it is 

 associated. (See p. 191.) 



In the Reports of 1S33- and ISSo an extended account of the rock is 

 •iiveii, wliicli is reprinted almost verljatim in the Rejiort of 1841,^ with the 

 sup|)ression of a single very suggestive theory. 



He describes the rock as a quaternary compound of feldspar, horn- 

 blende, quartz, and mica. He describes the "conglomerated sienite " of 

 Whately in detail: 



It is in fact a real conglomerate, and in some places the nodules are so numerous 

 that it lias very much the appearance of the coarse pudding-stones of the newer rocks. 

 The nodules vaiy in size from the diameter of half an inch to that of 6 or 8 inches. 

 They are not smoothed, like the pebbles in the more recent conglomerates, by mechan- 

 ical attrition, but they appear like masses of rocks that have been partly melted down 

 by heat. Upon the whole, I think I have ascertained the presence of hornblende- 

 slate, mica-slate, and quartz rock in these nodules. When the rock is broken they 

 are knocked out without difiQculty, like the pebbles of a common conglomerate. 



' Geology of Connecticut River: Am. Jour. Sci., 1st series, Vol. VI, p. 29. 

 ' Rept. Geology of Massachusetts, p. 463 

 'Ibid., p. 668. 



