Pirsson and Washington — Geology of Red Hill, JSf. II. 265 



Another dike of similar size and character occurs in the 

 road about 200 yards from the former up the mountain side. 



A dike of a more grayish color cuts the syenite about one 

 quarter of a mile above the Home farmhouse on the well 

 worn trail leading from it to the top of the North Peak, 



One of similar character to the last was found about half 

 way on the old trail from the highest farmhouse in the saddle 

 to the North Peak. 



Dikes of this kind occur also on the mountain side below 

 the Home farmhouse. 



Outside of the syenite they are also common in the gneiss, 

 and a considerable number have been found in the exposures 

 along the shores of Lake Asquam ; on Fore Point there are 

 several and the little capes of Long Point next southwest from 

 it and shown on the map contain several more. They occur 

 at considerable distances from Red Hill : thus they have been 

 found in the gneiss of Sheparcl's Hill, one in the hotel road- 

 way and others near the Norton house, and at the summit of 

 Mt. Livermore, in these cases some six miles distant from 

 the mountain. 



They are all very narrow, from one to three feet in width, 

 are very dark, quite compact, without noticeable phenocrysts 

 and very commonly are dotted with white amygdules of cal- 

 cite. In nearly all cases where the trend can be observed it is 

 directly towards Red Hill. The microscopic study shows that 

 they are all much alike, composed of plagioclase feldspar and 

 brown hornblende and are the rocks which have been called 

 camptonites. 



Breccia Intrusion. — In the sugar-maple grove just above 

 the Home farmhouse and north of the road there is an intru- 

 sion of a singular rock. The mass is not more than 100 yards 

 in diameter and is surrounded on all sides by the normal 

 nephelite syenite and is therefore judged to be an intrusion in 

 it, although the exposures were such that the actual contact 

 could not be found. It consists of a fine-grained, black rock 

 filled with fragments of nephelite syenite. Usually the frag- 

 ments are no more than single feldspars of the syenite which 

 then appear much like phenocrysts, but from this they increase 

 in size till they are considerable masses. They are so twisted 

 and broken and strung along in flow lines and bordered with 

 angular pieces of feldspar that at first glance it appears as if a 

 mixture of two magmas in the fluid condition had occurred 

 with subsequent crystallization. In some places there are 

 more inclusions than of cement ; in other places the reverse 

 is the case, and variations of this sort may be shown in a single 

 hand-specimen. Furthur details in regard to this are deferred 

 for consideration in the petrographical part of this work. 



