Gas-Well Sections in Central New York. — Prosser. 135 
27 mo Fine grains of whitish quartz 
sand. Similar sample at 
1 1 12. Laurentian 
28 1 1 14 Quartz grains with some of 
greenish color. Similar sam- 
ples from 11 16 and 1118 ft., 
but these contain more of 
the greenish grains. Laurentian 
29 1 120 Light gray quartz grains with 
some dark ones. Ditto 
from 1 122, 1 125 and 1127 ft. Laurentian 
30 1130 Larger proportion of the dark 
colored grains. Laurentian 
31 1 133 Fine grains of white quartz 
mixed with quite a large 
amount of the dark grains. Laurentian 
32 1 1 35 Fine grains with a larger pro- 
portion of the dark ones. 
Bottom of the well. Laurentian 
Diagrammatic Section of the Ilion Well. 
DEPTH, THICKNESS. FORMATION. 
195' 
475' 
580' 
630' 
1 105 ' 
1 135' 
195' 
280' 
105' 
50' 
Drift. 
Utica shale. 
475' 
30' 
Trenton limestone. 
Birdseye limestone; some of the lower 30 feet may 
be in the Calciferous. 
Calciferous formation. 
Laurentian gneiss. 
Bottom of Well. 
From tlie above section it will be seen that the Ilion well 
passed through 195 feet of superficial material before reaching 
bed rock. This proof of a former deep rock basin in the Upper 
