The Original Chnzij Bocks — Brainerd and Seehj. 325 
4. Similar to No. 3, but containing in addition to Maclvrea, various species of 
Ortboceras and large masses of Stromatocerium 90 
5. Less massive limestones, quite impure and often disintegrating into nodules 
as though shaly 60 
Grotip C. 265 
1. Dark, iron-grey, dolomite, weathering yellowish 1 
2. Blue, compact, fine grained, pure, limestone, containing fine lines of calcite. 6 
3. Dove colored, compact, brittle, perfectly pure limestone containing small 
nodules of calcite 5 
4. Iron-grey dolomite 3J^ 
5. Like No. 3, only containing larger nodules of calcspar 4)^ 
6. Dark grey, fine grained compact limestone somewhat impure, having a'mot- 
tled aspect when weathered, containing several undetermined species^of Afur- 
cbisonia Ortboceras Sbud usually enveloped in Strephochtus 2 
7. Iron-grey dolomite 1 
8. Blackish, impure limestone, abounding in Rbyncbonella plena SG'^ 
9. Dark or light grey, massive coar.sely granular limestone, mostly made up of 
crinoidal fragments which are sometimes red, containing Rbyncbouella... 2Q% 
10. Same as No. 8 32 
11. Measures concealed 7 
12. Tough, impure dolomite 8 
13. Concealed 24 
157 
Total thickness of A. B. and C 732 ft. 
The map covers a tract of nearly 1^ square miles, including 
the village and the farming land for a mile to the south-west. 
Through this region the rocks crop out, in hundreds of places, 
though more covered by soil than the map might lead one to 
suppose. The ledges dip in various directions, and the explorer 
who runs over them for the first time is greatly perplexed to 
make out the stratigraphy. Notwithstanding the even and reg- 
ular appearance of most of the exposures, the region has evi- 
dently been one of great disturbance though without any traces 
of the metamorphism due to heat. Two great faults run 
obliquely across the measures; one, from near the mouth of 
Tracy brook, south-easterly along the bed of the Little Chazy 
river for forty rods, and on past the south end of the ledge of 
Black River limestone; the other, crossing Tracy ^brook about 
thirty-five rods farther west, and running nearly due south by 
the compass through a point just west of Mr. Hyde's house. 
These two faults divide the tract into three areas Avhich for the 
sake of distinction we shall call the western,*central and north- 
eastern areas. 
There is evidence of further dislocation on the south. The 
ledge of Black River limestone south of Mr. Hayes' house be- 
tween the highway and the river dips south 52 degrees east, at 
an angle of only 5 degrees, and lies too far to the east toj^e con- 
