FLATTENED PEBBLES. 



35 



Single pebbles sometimes show striking curvatures, as in Fig. 13, where a represents a pebble ten inches 

 long, and a little more than one inch wide ; b shows a smaller one less curved, 5i inches long and half au 

 inch wide. 



Fig. 14 was copied from No. t T of the State FlG - 13 - 



Cabinet from Wallingford, one-fifth the natural 

 size. The bowlders of this conglomerate scattered 

 over the fields, often contain interesting exhibitions. 

 Fig. 15 was copied from one five feet long. It shows 

 a band of pebbles in the lower part, interstratified 

 with schist, and in the upper part a crooked vein 

 of white quartz. The lower part is what we not 

 unfrcquently meet in sandstone. The upper part 

 occurs almost exclusively in the highly metamor- 

 phic schists. 



FIG. 16. 



FIG. 15. 



A still more interesting case is shown in another 

 bowlder a few feet long, represented imperfectly in 

 Fig. 16. Here the folia of the schists are bent con- 

 siderably. On the inner side is a quartz pebble of 

 considerable size, which is elongated and bent some- 

 what ; but as we go outwardly the pebbles are so 

 much flattened that they can hardly be distin- 

 guished from the quartzose folia of the rock. At 

 the time this sketch was taken we did not fully 

 realize the important bearings it might have upon 

 theory, therefore we fear that it is not as minutely 

 accurate as to every pebble as could be desired. 

 Still the general facts above named are quite man- 

 ifest, and these are all that is important. 



The preceding facts would justify some inferences additional to those drawn from the 

 Newport rock. But we will first describe another locality on the east side of the Green 

 Mountains, where the metamorphic processes, begun at Newport and carried still farther 

 at Wallingford, are completed in the most satisfactory manner. It is at Plymouth, along 

 the west shore of Plymouth Ponds, most fully developed perhaps, just where the ponds 

 are separated by a mass of detritus, which was most probably the Moraine of an ancient 

 glacier, as will be described in another place. The schist here, which is decidedly for the 

 most part talcose schist, and not far from some of the gold diggings, has an easterly dip 

 from 50 to 60, in a direction a few degrees east of north. As the ledges crowd closely 



