Acts of the Legislature, II, 27, 31, 37, 38, 40, 44, 48,
61, 62, 65, 76, 77, 79, 80, 85, 90, 96, 97, 98, 105, 110,

III

Air-compressors, 144, 213

Allen, Horatio, 38, 42, 238

Allen, Stephen, 13, 28

American Cement Co. of Philadelphia, 193, 198
Amsterdam, New, 2

Analyses of waters used in New York, 284
Aqueduct Commission:

Commissioners, 110, 112, 113, 114, 115, 140, 203,

205

Engineers, 140, 150, 158, 195, 201, 203, 205
Organization and changes, 110

Secretaries, III, 112

Aqueduct, new:

Available head, 117, 184

Blow-offs, 136, 138

Capacity, 184

Construction, 114

Contracts, 286

Cross-section, 182

Divisions, 141

Formulæ for flow, 178, 181

Gaugings, 180

Grades, 116

Investigations for, 90

Location, 116

Brickwork made impervious to water, 70, 170
Brickwork, specifications for, 248, 253, 270
Bronx and Byram works, description of, 92
Bronx conduit put into service, 94

Bronx River as a source of water-supply, 6, 91

Browne, Dr. Joseph, 6, 7

Burr, Aaron, obtains charter for Manhattan (Water)
Company, 10, II

Burham Portland cement, 193

Byram River as a source of water-supply, 91
Cable for Sodom Dam, breaking of, 194
Cable for Sodom Dam, description of, 194

Cages used in shafts of new aqueduct, 146, 227

Campbell, Allan, 81, 90, 104, 106, 110

Cartwright, Geo. W., 33

Celebration of completion of old Croton works, 46
Chesborough, E. S., 108

Chezy formula, 178

Cholera, ravages in 1832 of, 21

Christiaensen, Hendrick, 1

Church, B. S., 62, 83, 104, 140, 195

Clendining Valley:

Arches omitted at, 43

Crossing of, 57

Clinton, Col. De Witt, reports on water-supply, 21

Collect Pond, 2, 4, 6

Colles, Christopher, 4, 6

Commissioners:

Aqueduct, 110, 112, 113, 114, 115, 140, 203, 205

Aqueduct Department, 61

Public Works, 81

Water, 28, 31, 43, 48

Committee of citizens, 109

Common Council, actions of, 5, 6, 7, 10, 13, 35, 36, 44

Construction of new Croton Dam, details of, 207

Consumption of water, 1840-1894, 107

Contracts for change of aqueduct, 77

Contracts for high-service works, 76, 96, 98

Contracts for new aqueduct, 286

Contracts for new aqueduct, form of, 241

Contracts for new reservoirs, 89, 195, 197, 200, 205,

209, 286

Contracts for old aqueduct, 37, 38, 40, 43, 72

Contracts for old reservoirs, 66, 79, 87, 88

Contracts for pipes, 43, 72, 77

Contracts for pumping-engines, 76, 96, 97, 98

Cooper's, Judge, proposal, 7

Cost of water-works, 311

Crane's, Sayrs, proposal, 6

Croton works, old, completion of, 48

Culverts for old aqueduct, 54

Current meter used in new aqueduct, 180

Curtis', Zebina, proposal of, 6

Cuts, open, for new aqueduct, 118

Dams constructed :

Amawalk, 88

Bog Brook, 195

Boyd's Corners, 79, 87

Carmel, 201

Croton, new, 205

Croton, old, 45, 49, 63

Middle Branch, 88

Muscoot River, 88

Sodom, 192

Titicus, 197

Dams proposed:

Garretson's Mill, 33

Halman's Mill, 33

Muscoot Hill, 29

Quaker Bridge, 109, 113, 204

Department of Public Works created, 80

Dewey, Timothy, favors a supply from the Bronx, 27
Diamond-drill, description of, 221

Disbrow, Levi, successful in sinking Artesian wells,
15, 26

Divisions of New Croton Aqueduct, 141

Divisions of Old Croton Aqueduct, 38

Douglass, Maj. D. B., 28, 30, 31, 36, 37, 38, 39, 235
Droughts, 84, 85

Earthen dams, 57, 66, 88, 89, 195, 199, 202, 206
East Branch reservoir, 85, 112, 115, 191
Electric-light plants on New Aqueduct, 145, 293, 295,

297

Ellet, Chas., proposes suspension bridge across Har-
lem River, 39

Engineers consulted by Department of Public Works,

113

Engineers consulted by Water Commissioners, 33
Engineers of Aqueduct Commission, 140, 150, 158,
195, 201, 203, 205

Engineers of Croton Aqueduct Department, 61, 62,
71,73, 78

Engineers of Department of Public Works, 81, 90, 91,
93, 96, 103, 204

Engineers of Water Commissioners, 28, 33, 37. 38
Fences along old aqueduct, 37, 64

Flow in new aqueduct, 178, 183, 307

Flow in old aqueduct, 46

Flume, 200, 202

Formulæ for flow, 178, 181

Formulæ for head required, 186

Freshets, 45, 63, 232

Fteley, A., 140, 181, 190, 201, 203, 204

Gate-houses of Central Park reservoir, 67, 69,

of new aqueduct, 127, 131, 135, 136

of new reservoirs, 193 196, 197, 199,
202, 206, 207, 210

of old aqueduct, 52, 54, 56, 58, 60

Gauging flow through new aqueduct, 180

Geological formations along new aqueduct, 118
Grades of new aqueduct, 117

Grades of old aqueduct, 51

Greene, Gen. Geo. S., 61, 71, 75, 79, 113

Ground-water entering new aqueduct, 126

Grouting defective masonry, 171

201.

Stephens, Samuel, 16, 20, 43

Sullivan's, John L., proposals, 17, 25, 26

Supply from Croton River, 308

Surveys for new aqueduct, above and below ground,
173

Swan, Cyrus, recommends a supply from the Croton
River, 20

Taylor's, Benjamin, proposal, 6

Tea-water Pump, Old, 3, 6

Timbering new aqueduct tunnel, 123, 155, 159, 162
Tracy, E. H., 74, 81, 239

Tunnel for new aqueduct, how excavated, 122
Tunnel under Harlem River, proposed for old aque-
duct, 41

Tunnelling, cost of labor on new aqueduct, 149
Tunnelling, ordinary method for new aqueduct, 146

Tunnelling through sand and gravel, 158
Tunnelling through seamy and blocky ground, 161
Tunnelling through soft ground, 152

Tunnelling under the Harlem River for the new
aqueduct, 159

Wages paid on new aqueduct and reservoirs, 287
Waste-detector of B. S. Church, 104

Waste of water, 48, 64, 104

Waste of water, methods of detecting, 104
Waste-weirs, see Overflow-weirs.

Water, sold in hogsheads, etc., 4, 22, 23
Water Commissioners, Board of, 28, 31, 43, 48
Water Commissioners' report, 30, 31
Water-meters in use, 105, 106

Water-meters, saving effected by use of, 106
Water-phone for detecting waste, 105
Water-rates established in 1887, 280
Watershed of Bronx and Byram rivers, 93
Water-shed of Croton River, description of, 188
Water-stock, issue authorized, 31, 36, 38, 43, 44
Water-supply, complaints about, 6, 13
Water-towers, 76, 96, 98

Waters, analyses of, 284