116 NEW YORK STATE MUSEUM 



in the river bed (see pi. 8). There are also bands of reddish ortho- 

 clase gneiss along with the dark amphibolite gneiss, which are 

 thought to be a part of the series and to have nothing to do with 

 the granite, though decisive evidence on this point is lacking. 



Though no large masses of this granite have been discovered, 

 the total amount present is considerable. While clearly intrusive 

 in the gneiss and hence younger, it is thought to be much older 

 than the anorthosite, implying also that the amphibolite-gneiss 

 is older than the gabbro. The reasons for holding this view are 

 briefly as follows: 



1 The amphibolite gneiss is very widespread in Dickinson and 

 Waverly townships, and does not show massive cores, such as are 

 nearly always found in the hyperites, which are known to occur 

 only in small masses or in dikes. Two such small masses 

 occur in the immediate vicinity, one to the south of the 

 falls along the railway and the other near the road less 

 than 2 miles west of the village, both with unchanged cores 

 and gneissoid periphery. While no contacts show, these outer 

 gneisses differ somewhat in appearance from the main body of 

 gneiss and are not at all involved with granite. The presence of 

 granite, the more widespread character of the deposit and the 

 more complete metamorphism are the reasons for assuming the 

 older age of the amphibolite rather than regarding it as identical 

 with the gabbro. 



2 The granite occurs so abundantly and constantly cutting 

 these rocks that it seems incomprehensible that it should not be 

 found cutting the syenites and anorthosites to the south if it is 

 really younger than they. This association of this red granite 

 with amphibolite and also with orthoclase gneisses is constant 

 in the northern Adirondacks and must have some significance. 



There are however later granites also. Those associated with 

 the syenites and distinguished by their coarse grain and spindle- 

 shaped quartz have been already described. In addition small 

 masses of granite have been found in a few places in the anortho- 

 site, but unfortunately their precise nature is not clear. They re- 

 semble the older granite, and some of them are unmistakable in- 



