INDEX 
Page 
Acknowledgments to those aiding 21, 23 
Amethyst avenue, foundations on, bed rock 
in 72 
Amsterdam avenue, foundations on and 
near, bed rock in 74-76 
Anthony avenue, foundations on, bed rock 
in 71 
Aqueduct, new, section of Harlem River 
at, bed rock in 42 
Assistance from others 21, 23 
Bed rock, depth and nature of, study of 20-21 
depths to, tables of 30-93 
exposures of 21-22 
form of 21-29 
maps showing 11, 20, 22 
sections of 25, 26, 28 
See also names of localities, streets, etc., 
Foundations, etc. 
Bedloe Island, bed rock on, depth to 40 
Boston road, foundations on, bed rock in.. 72 
Broadway, bed rock on and near 44-45, 
49-54,57,66-68,73,76,81 
buildings on and near, foundations of, 
bed rock in 52-54 
sections along, figures showing , 28 
Bronx, Borough of, bed rock in 87-89 
Brooklyn, bed rock in 83-86 
Brooklyn-New York tunnel, bed rock in . . . 35 
Buildings in Manhattan, foundations of, bed 
rock in 51-55, 71-76 
Central bridge, sections of Harlem River at 
and near, bed rock in 43 
Cozzens.Isaachar, onNewYorkCitygeology . 12 
Credner, Hermann, on New York City ge- 
ology 13 
Dana, J. D., on New York City geology 14 
3t River, channels of, bed rock in 30-35 
character of 21 
sections across 32-35 
East River bridge, approach to, bed rock at. 76 
section at, bed rock in 32-34 
East River Gas Company, tunnel of, bed 
rock in 32 
East River reefs, bed rock in, depth to 34 
Eckel, E. C, on New York City geology. ... 16 
Eighth avenue, bed rock near 55-57 
Eleventh avenue, bed rock near 55, 68 
section along, figure showing 28 
Faulting, importance of 20 
Fifth avenue, bed rock on and near 56, 
57, 68-70, 80-82 
buildings on and near, foundations of, 
bedrock in 54-55 
Page. 
Fifty-ninth street, line of, bed rock on 41 
First avenue, bed rock near 57-58, 74-75, 80-81 
Fort Lee, N. J., bed rock at 93 
Forty-second street, section of East River 
on line of, bed rock on 34 
Foundations in Manhattan, bed rock in 51- 
55, 71-76 
Fourth avenue, bed rock on 56, 58-59, 81 
Fulton avenue, foundations on, bed rock in. 71 
Gale, L. D., on New York City geology 12 
Gneissoid "islands" in New York, location 
of 12,21-22 
location of, figures showing 15 
Gratacap, L. P., on New York City geology. 16-17 
Greatneck, N. Y. , bed rock at 93 
Greenport, N. Y., bed rock at 93 
Harlem, bed rock in, character of 27-28 
depth to 23-24,27 
Harlem River, channel of, bed rock in 41-44 
sections across, figures showing 26 
Hell Gate, channel at, character of 21 
Highbridge, section of Harlem River at, 
bed rock in 42 
Hobbs, W. H., on New York City geology.. 19 
Hoboken, bed rock in 89-92 
water front of, bed rock at 89-91 
Hudson River, area west of, bibliography 
of 19 
channels of , bed rock in 36-41 
character of 21 
sections of 40-41 
Jackson avenue, foundations on, bed rock 
in 72 
Jersey City, bed rock in 92-93 
Julien, A. A., on New York City geology. . . 17-18 
Kemp, J. F., on New York City geology ... 14-16 
Lenox avenue, foundations on and near, 
bed rock in 73, 81 
section along, figure showing 28 
Lexington avenue, bed rock on 45-48,56,68 
Long Island City, bed rock in 86 
McAdoo tunnel, bed rock in 40 
Macomb's dam, section of Harlem River at, 
bed rock in 43 
Madison avenue, bed rock near 56, 58, 68-69 
Madison avenue bridge, section of Harlem 
River at, bed rock in 44 
Manhattan Island, bed rock of, depth to.. 22-24, 
44-82 
bed rock of, exposures of 21-22 
form of 21-29 
buildings on, foundations of, bed rock 
in 51-55,71-76 
95 
