REPORT OF THE DIRECTOR AND STATE GEOLOGIST r23 



by him. 1 The eastern one can be followed as far south as 

 Saratoga. 



To the south of Lake George the valley is filled with sand, and 

 every indication is afforded that the lake formerly extended much 

 farther to the south. The divide near Bloody pond, between 

 the Lake George drainage and the Lake Champlain drainage via 

 Glen lake. Halfway creek and Wood creek, is almost imper- 

 ceptible. 



The rock formations, or hard geology, of Caldwell embrace 

 gneiss, gabbro, and calciferous limestone, and, if the same pro- 

 visional arrangement in series be followed as in our previous 

 reports, they would be described as follows. 



Series 1 The gneisses constitute the high ridges and adjacent 

 foothills. The commonest variety is a light colored, rather 

 acidic rock, of which we select specimen 30, from the crossroads 

 on the lake shore, about 3 miles from the head of the lake, as the 

 typical case. It is strongly foliated and has evidently been very 

 severely squeezed in dynamic metamorphism. The foliation, 

 which is made apparent by the dark silicates, is however due to 

 the parallel alignment of many small, dark patches, which are 

 not continuous. They might easily result from foliation induced 

 by pressure in a rock originally massive and provided with a 

 moderate percentage of dark silicates. Under the microscope it 

 is evident that the component minerals are quartz, microperthite 

 and hornblende, all greatly granulated. The mineralogy shows 

 some marked resemblance to the syenitic rocks, described by 

 H. P. Cushing from Loon lake, in the northern Adirondacks, 

 but the rock is seldom as pronounced a green, and some hesita- 

 tion is felt by us in drawing a more emphatic parallel than the 

 statement of this mineralogic resemblance. If it could be shown 

 anywhere that crystalline limestones were interbedded in the 

 gneisses, we would be compelled to pronounce them sedimentary. 



iDarton, N. H. Geology of the Mohawk valley, 13th an. rep't N. Y. state 

 geologist. 1893. p. 409, specially 425 and 429. Preliminary description of the 

 faulted region of Herkimer, Fulton, Montgomery and Saratoga counties, 

 14th an. rep't N. Y. state geologist. 1894. p. 30, specially p. 52. 



