roO NEW YORK STATE MUSEUM 



makes eome 60)^ of the rock and is beautifully marked micro cline. 

 Quartz constitutes 20^ to 25^, much of it occurring as inclusions 

 in the feldspar. From Piercefield on northwest to GTale's and 

 beyond little else than red, granitic gneisses occurs. 



Child wold station is 2 miles west of Piercefield. Between the 

 two there is but one rock cut (1006), situated J mile eaet of Child- 

 wold. This shows the same combination of fine grained, green, 

 gneiss and red, granitic gneiss found in the cuts east of Pierce- 

 field. The strike of these rocks is from n.65 w.to n.75 w.,so that, 

 since crossing the Raquette the railway has followed the strike 

 of the belt. At Childwold the southerly direction is resumed, and 

 different rocks are at once met. At | mile south of Childwold 

 station is a considerable cut (1007) in a greenish, rudely gneissoid 

 rock, which is a decidedly different looking rock from the green 

 gneiss of the preceding exposures and seenus certainly referable 

 to ordinary augite syenite. It is a much firmer, more massive 

 rock, lacks the granular look, is not evenly but very rudely 

 foliated and is much more plainly an igneous rock. Nor is there 

 any associated red gneiee. It also has the precise mineralogy of 

 the augite syenite, the same augite and bronzite with their char- 

 acteristic parallel growths, subordinate hornblende, the three 

 together constituting only some 10^^^ of the rock, which is pre- 

 dominantly feldspathic. The feldspar is mainly microperthite 

 though with considerable oligoclase and some feldspar of uncer- 

 tain nature. There is barely lii of quartz. There are some 

 amphibolitic streaks which may represent either stretched segre- 

 gations or inclusions, probably the former. 



East from this point and lying between it and Big Tupper lake 

 is the large irregular mass of Arab mountain. In a trip across 

 through the w^oods no rock was eeen other than that which 

 seemed clearly referable to the augite syenite, though the numer- 

 ous exposures are of the unsatisfactory character usual in the 

 woods, largely moss-covered and not furnishing fresh material. 

 This line is parallel to and not far south from the belt of red 

 and green gneisses along the railway, just described. 



