﻿220 NEW YORK STATE MUSEUM 



Feet 



8600 To Broadway — Manhattan schist (little known except 

 from tunnels already made) 

 14000 To East river, probobly Manhattan schist (same as line A) 

 6000 Manhattan island to City Hall, Brooklyn — uncertain con- 

 dition (same as on line A) 



SUMMARY OF LINE B 



Feet 



8 000 Yonkers gneiss — good quality 



13000 Fordham gneiss — good quality 



21400 In wood limestone — variable quality 



12800 Manhattan schist — good quality 



23 400 Estimated Manhattan schist — fair 



6 000 Almost unknown 



84 600 total 



Line C. Going south from Hill View reservoir 



Feet 



6 000 Yonkers gneiss — good rock 

 17400 To Webster av. — Fordham gneiss — good rock 



5 000 Along contact between limestone and gneiss 



9800 To 138th st. — Inwood limestone with probably two bad 



zones 

 1 800 To Bronx kills — along contact between limestone and 



gneiss — uncertain quality 

 600 Across Bronx kills — mostly in limestone containing a 



fault zone — probably bad ground 



6 400 Crossing Randall's and Ward's islands and Little Hell Gate. 



Nearly all is Manhattan schist of good quality 

 1000 Crossing Hell Gate— Inwood limestone 

 1 200 Crossing Hell Gate — Fordham gneiss of good quality 

 1 800 Astoria point — probably Fordham gneiss of good quality 

 1 000 Crossing another limestone belt 



1 000 To Vernon av. — Fordham gneiss of unknown quality con- 



taining one fault zone 



7 000 To Nott av. — Ravenswood grano-diorite — good rock 



2 800 To Borden av. — Probably Ravenswood grano-diorite. 

 18400 To Fort Greene Park Brooklyn — almost wholly unknown 



but contains probably 5000 or 6000 feet of poor ground 



