404 STRATIGRAPHICAL GEOLOGY. 



is a conglomerate upon its summit, associated with porpliyry, both of 

 whicli are unhke anything in the neighborhood, while slightly similar to 

 certain ledges in the White Mountain district. The phenomena upon 

 this mountain have been described in the Vermont report (vol. ii, pp. 

 565, 624) as illustrations of the alteration of conglomerate into porphyry 

 and granite. It is stated that 



On the top, just where the southern slope begins, masses of a conglomerate of a 

 decided character, several feet and even rods wide, appear on the side of porphyry 

 and granite. All traces of stratification in the conglomerate are lost, and it passes, 

 first, into an imperfect porphyry, and this into granite, without hornblende, in the 

 same continuous mass, without any kind of a divisional plane between them. Where 

 the conglomerate is least altered, it is made up almost entirely of quartz pebbles and a 

 larger amount of laminated grits and slate, the fragments rounded somewhat, and the 

 cement in small quantity. It is easy to see that a metamorphosis has taken place in 

 all the conglomerates, and some of the pebbles might even be called mica schist. In 

 the cement, also, we sometimes see facets of feldspar. In short, it is easy to believe 

 that the process of change need only to be carried further to produce sienite, por- 

 phyry, or granite. One cannot resist the conviction that the granite rocks of this 

 mountain are nothing more than conglomerate melted down and crystallized, or, at 

 least, that such was the origin of a part of them. [Page 566.] 



The basis of this theory rests largely upon the supposition that these 

 three kinds of rock occur along the line of strike. A revisit to the 

 locality in 1872 shows that these three sorts of rock occupy different 

 layers, the strike being N. 80° W., or nearly at right angles to the course 

 common in the neighborhood. The ledge exposure showing them all is 

 continuous. I do not see why the change in the direction of the strike 

 should have been overlooked in 1858. The fact of this change in the 

 strike, together with a variation in the nature of the rock material, sug- 

 gests whether we have not here the relic of a different formation, resting 

 upon the gneiss. We shall see presently that it extends farther east than 

 the gneiss, bordering the granite of the larger mountain. Little As- 

 cutney has two peaks. The more northerly one is close by Mill river 

 in West Windsor; the other, which is higher, is in Weathersfield, over- 

 looking Black river. I will describe the rocks as they occur on a line 

 from about the house of Mrs. T. Piper in Weathersfield, — the southern 

 foot of the mountain, — over the two peaks towards Brownsville in West 

 Windsor. The south slope is quite steep, and furnishes several outcrops 



