278 
ANNALS NEW YORK ACADEMY OF SCIENCES 
Serial No. 
Original 
mark 
Location 
Depth 
to Rock 
To Rock 
U. S. 
datum 
Rock 
penetra¬ 
tion 
Form¬ 
ation 
Variety and remarks 
286 
6 
Gas works, Law¬ 
rence Point 
52' 
-34' ± 
1220 + 1 
Ford. 
Chiefly granite gneiss, 
with banded gneiss and 
pegmatite. 
287 
4 
Gas works, Law¬ 
rence Point 
350' + 
Well 400' deep, granite 
gneiss. 
Governors Island 
Two deep wells were bored for water — one near the Hospital at the 
north margin of the island and one in the moat of Fort Columbus. Mate¬ 
rial all in fragments (sand) and chips. Housed at the Quatermaster’s 
Department, Governors Island. P. & J. Conlin, contractors. 
Serial No. 
Original 
mark 
Location 
Depth 
to Rock 
To Rock 
U. S. 
datum 
Rock 
penetra¬ 
tion 
Form¬ 
ation 
Variety and remarks 
2SS 
The well near the 
Hospital drilled 
1901-02 
73' 
-60' + 
1725' 
Manh. 
Many samples of mica 
flakes and quartz mica 
mixture. Coarse mica 
schist, fine hornblende 
schist and pegmatite all 
represented. 
289 
A second well in 
the moat of Fort 
Columbus 
300' ± 
Well 350' deep. Rock 
not seen. 
Plunger Elevator Holes on Manhattan 
The cores taken from these holes have not in most cases been found 
complete, but enough in the following ones could be seen to determine the 
formation. The place where the material can be seen is indicated in each 
1 There are several other shallower wells at this place. No. 286 has been continued 
and now- reaches to a depth of approximately 2000' with no material change in the rock. 
