BERKEY, GEOLOGY OF SOUTHERN MANHATTAN ISLAND 279 
Serial No. 
Original 
mark 
Location 
Depth 
to rock 
To Rock 
U. S. 
datum 
Rock 
penetra¬ 
tion 
Form¬ 
ation 
Variety and remarks 
290 
Trinity Bldg. 
Manh. 
Typical mica schist show- 
ing dip of 60 0 . 1 
291 
The Ansonia, 
“ 
Mica schist, typical, dip 
Broadway & 74th 
almost vertical. 2 
St. 
292 
Fifth Ave. Hotel, 
2100'± 
“ 
Mica schist, grayish, fine 
Fifth Ave. & 
grained, dip 30°-35°. 3 
23rd St. 
293 
Tribune Bldg., 
about 
“ 
Mica schist, typical. 4 
154 Nassau St. 
250' 
Brooklyn Wells and other Brill Borings 
Serial No. 
Original 
mark 
Locat ion 
Depth 
to rock 
To Rock 
U. S. 
datum 
Rock 
penetra¬ 
tion 
Form¬ 
at ion 
Variety and remarks 
294 
New Amsterdam 
Ford. 
Banded white and black 
Gas Company, 
granitic gneiss, typical 
Ravenswood 
Fordham with some peg- 
matite and micaceous 
portions. 5 
295 
St. George’s 
160' + 
240' + 
“ 
Granitic gneiss quartz- 
Hotel, w'ell at 58 
below 
biotite feldspar rock. A 
Pineapple St. 
surface. 
little garnet. 6 
296 
Foot of Atlantic 
120' 
“? 
White and black banded 
St. 
below 
granitic gneiss. 7 
surface. 
1 Specimen of core taken from 335 ft. below the sidewalk is in the American Museum of 
Natural History. 
2 Specimen of core taken from 127 ft. below the surface is in the American Museum of 
Natural History. 
3 Diamond drill boring. Specimen of core taken at a depth of 1224 feet is in the col¬ 
lection of the New York Mineralogical Club at the American Museum of Natural History. 
4 Nine holes were made. Only one piece of core was seen. Bed-rock said to be at a 
depth of 140-160 ft. Piece of core is in the office of the Superintendent of Building. 
5 Three pieces of an 8-inch core were seen at the Ravenswood plant. 
6 The material is wholly in granular fragments due to the method of drilling. A very 
complete series of samples has been preserved at the hotel. Drilling was in progress when 
examined. The final depth will be somewhat greater. 
7 Pieces of core from this hole are preserved in the Long Island Historical Museum, together 
with pieces from three others. All have been given the same number in the museum and there¬ 
fore it is impossible to be certain that they may not have become interchanged, but by a careful 
comparison of the four lots and their localities, it seems reasonably sure that this hole is correctly 
represented by the pieces of banded Fordham gneiss. 
