Massive Crysfalline Rocks. 



115 



places into a true gneiss, it comes to its end against soda-granite and 

 quartz-diorite. Thus witliin a breadth of only 250 to 350 yards, 

 there is here a passage from a stratum of crystalline limestone 

 through conformable schists, to the massive rocks along which we 

 have to look for contact-phenomena. 



The facts here described are mostly from three south-to-north 

 sections : Section 1, 800 to 400 yards west of the Station (l to n, on 

 the map) ; section 2, about 700 yards (p) ; section 3, about 900 yards 

 (^tos). _ 



In section 1, I to m is the schist ; at m is soda-granite, which 

 becomes hornblendic twenty-five feet above, toward the road ; and 

 then at n, on the north side of the road, the rock is of coarse quartz- 

 diorite. (The locality n is that of the first outcrop of rocks o\\ 

 the road going north-west from the railroad station.) The contact- 

 phenomena in this section are as follows. 



In the first place, the mica-schist is even in bedding against 

 the limestone ; becomes more and more contorted to the northward, 

 or away from it ; and is full of flexures of a yard or so in span for 

 the last fifty feet or more south of the junction with the granite. 



With the increase in the flexures of the layers, the schist becomes 

 interlaminated with nodose-lines of quartz, vein-like in origin ; 

 and, besides, the garnets become somewhat larger. At the junction 

 referred to, the schist is mostly a garnet rock containing much 

 fibrolite and staurolite, and the latter is in some places granular- 

 massive in a small way. Just below the granite, the layers are a 

 compact body of flexures, and in the soda-granite there is another 

 flexed layer rather faintly indicated. 



Figure 9 represents the condition here described ; it was taken 

 from the west side of a little bluff at m ; the height is twenty feet. 

 The dotted portion is that of the soda-granite. The garnet rock of 

 the flexures under the granite contains, like the granite, soda-lime 

 (or triclinic) felspars, with little orthoclase; and the first foot of 

 Fig. 9. Fig. 10. 



lilSli 



'••\--.^':':'' '■■■'•:■■':■'■ ■/■\'-''^ 



the granite is strongly garnetiferoi^s ; — facts which show a degree 

 of transition in the material of the two rocks. The flexed bed 

 within the soda-granite is gneissoid in character and of darker 



