66 ROCK FLOOR OF GREATER NEW YORK. [bull. 270. 
Summary of records of borings made in New York and vicinity— Continued. 
2. BORINGS IN THE BOROUGH OF MANHATTAN— Continued. 
Location. 
Rivt rside Park extension— Continued. 
Twelfth avenue— Continued. 
20 feet south of 902 
25 feet south of 903 
5 feet south of 904 
25 feet south of 905 
200 feet south of 896 
25 feet south of 907 
25 feet south of 908 
25 feel south of 909 
25 feet south of 910 
25 feet south of 911 
80 feet east of northeast corner 
158th street. 
25 feet north of 913 
25 feet north of 914 
25 feet north of 915 
25 feet north of 916 
25 feet north of 917 
L60 feet north of 913 
100 feet east of 919 
L60 feet south of 920 
Riversidt viaduct. 
Throughout length « 
Manhattan viaduct on Broadway, b 
125th street 
L26th street 
127th street 
Manhattan street 
129th street 
130th street 
50 feet south of 131st street . . . 
131st street to 133d street 
Depth of boring to rock. 
As given. 
Referred 
to U. S. 
datum, 
Sandy 
Hook. 
- 5.66 
2 
-11.50 
4 
12.33 
4 
14 
6 
14.50 
— ,7 
15 
- 7 
L6.33 
- 8 
15. 16 
- 7 
L6.66 
- 9 
is 
-10 
- 8 

5.50 
2 
- 8.33 

5.66 
2 
8. 16 

7.66 

5. 16 
3 
5 
3 
3.50 
4 
-60 
-47 
-13 
-10 
-13 
-30 
- 6 
-13 
13 
- 9 
26 
- 5 
39 
{ •=* } 
38 to 59 
Kind of rock, if known. 
Roek or bowlder. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
Do. 
No rock. 
No rock. 
Do. 
Do. 
Do. 
Do. 
Do. 
( rneiss. 
Do. 
a Williamson, F. S., consulting engineer, 25 Broad street. Riverside viaduct extends nlon 
Hudson River from L27th streel to 135th street. Wash borings were madeat short intervals forth 
entire distance to depths of 60 feet, and al the corner of 131st street and Twelfth avenue todejt 
of 7;> feet. No rock was encountered. The elevation of the street throughout is 12.5 feet above inea 
tide. (For 96th street viaduct see serial number 1199, p. 80. 1 
?>Klapp, Eugene, division engineer, rapid transit commission. "Rock not sounded," 
