264 
ANNALS NEW YORK ACADEMY OF SCIENCES 
a) Brooklyn Tower foundation. ( Continued .) 
Serial No. 
Original 
mark 
Location 
Depth 
to rock 
M. H. W. 
To Rock 
U. S. 
datum 
Rock 
penetra¬ 
tion 
Form¬ 
ation 
Variety and remarks 
49 
G 2 
S. pier S. W. 
corner 
-89.4' 
-86.73' 
10.58' 
Ford. 
Hornblendic gneiss, some 
strongly banded. 
50 
H 2 
S. pier S. E. cor¬ 
ner 
-81.0' 
-78.33' 
13.29' 
Granitic gneiss, 8' core, 
50°-60° dip. 
51 
K 
N. pier N. E. cor¬ 
ner 
-102.3' 
-99.63' 
7.8' 
Gray granitic gneiss, 6' 
core. 
52 
L 
N. pier S. E. cor¬ 
ner 
-88.0' 
-85.33' 
13.0' 
Gray granitic gneiss, 10' 
core. 
53 
M 
N. pier N. W. 
corner 
-104.0' 
-101.33' 
11.0' 
Hornblendic granitic 
gneiss, typical Fordham, 
6' core, 10°-30° dip. 
54 
N 
N. pier S. W. 
corner 
-86.0' 
-83.33' 
10.5' 
Granitic gneiss, 10' core. 
6) New York anchorage. 
55 
A 
Near S. W. cor¬ 
ner of anchorage 
-65.2' 
-62.53' 
? 
Banded hornblendic 
granitic gneiss and schist, 
uncommon, 14' core, 45° 
dip. 
56 
B 
Tompkins St. 
near S. E. .corner 
-64.4' 
-61.73' 
? 
Banded granitic gneiss, 
micaceous, 9' core, 30° 
dip. 
57 
C 
W. side E. of 
center line 
-70.8' 
-68.13' 
? 
Streaked micaceous gran¬ 
ite gneiss and pegmatite. 
8' core. 
58 
D 
E. side, N. of 
center line 
-69.5' 
-67.83' 
? 
“ ? 
Fine grained, garnet if- 
erous mica gneiss. Up¬ 
per part unusual type. 
Lower part favors Ford- 
ham 7' core, steep dip. 
59 
E 
N. W. corner 
-63.6' 
-60.93' 
? 
“ ? 
Mica gneiss, coarser than 
usual, 8' core. 
60 
F 
N. E. corner 
-63.1' 
-60.43' 
? 
“ ? 
Mottled grayish grano- 
diorite gneiss, with gar¬ 
nets, 12' core. 
61 
G 
N. E. corner 20' 
W. 
-60.2' 
-57.53' 
? 
“ 
Streaked micaceous gra¬ 
nitic gneiss. 
62 
H 
S. E. corner 
-95.1' 
-92.43' 
? 
Grayish, garnetiferous, 
granitic gneiss. Mostly 
typical Fordham, 124- 
core. 
63 
K 
N. W. of center 
-76.5' 
-73.83' 
? 
Granitic gneiss. Upper 
portion micaceous and 
garnetiferous, lower typi¬ 
cal Fordham. 
64 
I 
S. clearance line 
of bridge 
-71.7' 
-69.03' 
? 
Grayish, micaceous, 
banded granitic gneiss, 
8' core, typical. 
