196 



GEOLOGY OF OLD HAMPSHIEE COUNTY, MASS. 

 Analyses of the amphibolites, by L. G. Eakins. 



PEOJECTION OF THE LIMESTONE AND AMPHIBOLITE OF THE CONWAY SCHIST 

 THROUGH THE LEYDEN ARGILLITE IN WHATELY. 



Following the road west from the hotel in Whately, one comes in a 

 few steps upon a bridge over a small brook, and to the north across the 

 brook a fresh surface has been exposed in the bluff by blasting. An inspec- 

 tion of the wall reveals small spots of pyinte as the probable cause of the 

 blasting, and, what is of greater interest, one soon finds that a small boss 

 of the black limestone and the amphibolite of the Conway series, both of 

 which are in place a considerable distance to the west, has been here 

 thrust up tlu-ough the argillite with great force. The argillite dips away 

 from the limestone on both sides and mantles round its end, as shown in 

 fig. 11. 



A few rods up the brook, on the other side of the road, several similar 

 bucklings of the limestone and hornblende rock up through the argillite 

 may be seen. This shows, of course, that the Conway mica-schists are 

 earned far beneath the argillite and thus are older than it. The amphib- 

 olite and the limestone are identical with those farther west in the Conway 

 schist and are described above. As an indication of the force with which 

 the limestone was thrust up through the newer rock, there follows a 



