614 
INDEX. 
Day, its length influenced by tempera¬ 
ture, 220 - 221, 630 - 632, 638 - 
639. 
— calculation of, 638 - 639. 
— length of, at different geological 
epochs, 220 - 221. 
Daubeny, Prof. 106. 
Deposition of quaternary, 148. 
Delaware quaternary, 2. 
Deltas of various streams, 6, 7, 8. 
Delthyris, 338, 339, 342, 343, 345. 
Delthyris shaly limestone, 325, 343. 
Deposition, laminae of, distinct from 
stratification, 148. 
Deranged strata, 330 - S36, 367 - 396, 
403. 
Deranged and folded strata, 298, 405. 
— Champlain division, 370, 373,381, 
382, 386. 
— of Long-island division, 419, 420, 
434, 435. 
Desmidiacea, 51, 54. 
Details of geological survey of New- 
York island, 581 - 604. 
Dewey, Prof. 383. 
Diagonal cleavage of slate, 370. 
Diallage, 465, 483, 577. 
Diary of geol. survey of N. Y. island, 
581 -604. 
Dicotyledonous plants, 29. 
Dicranurus, 345. 
Dictyocha, 50. 
Differential of geological periods, 221. 
Diluvion or drift distinct from the upper 
drift, 130. 
Diopside, 481, 531, 532, 539. 
District, First Geological, extent of, 1. 
Disintegration of rocks, causes of, 37. 
Diseases caused by the stagnation of 
marshes, 9. 
— modification of, 246. 
— and its synonims, 158. 
— discussion on its origin, 216-228. 
Disadvantages of the Shawangunk lead 
mines, 361. 
Discussion of the origin of the drift, 
216 - 228. 
Dislocations, 430. (Vide faults.) 
Disbrow, Mr. 134. 
Division of the rock formations, 2. 
Division, Alluvial, 4- 123, 229-245. 
— Catskill, 299 - 316. 
— Champlain, 299, 366 - 422. 
— Coal, 295, 298. 
— Drift, 158, 228, 
— Erie, 299, 317 - 324. 
— Helderberg, 299, 324 - 353. 
— Long-island, 246, 248-278. 
— Ontario, 299, 353 - 365. 
Division, Quaternary, 123 - 158i 
— Ked-sandstone, 246, 248, 285 - 
294. 
— Trappean, 246, 248, 278 - 285. 
Divisional planes of slate, etc. 388. 
— roof slate coincident with strata, 
420. 
Dip of strata, 251, 252, 253, 255, 264, 
381, 382, 386, 405, 407, 408, 409, 
410, 412, 414, 427, 450,451,452, 
454, 455, 457, 583 - 604. 
Dip of strata of red sandstone, 281. 
— explained, 293. 
— of old red sandstone, 306. 
— Erie division, 316, 317. 
— Helderberg division, 330-336,351. 
— metamorphic, 443. 
— Potsdam sandstone, 419. 
— Shawangunk grit, etc. 356 - 357, 
359. 
— laconic rocks, 422, 429, 449. 
— primary, 520 - 620, 543 - 546, 583 
-604. 
— tables of, 606 - 622. 
— not perpendicular to the axis of 
elevation, 333, 356, 357, 517. 
— of rocks from Pine hill to Green- 
pond mountain, 363. 
Disintegration, 37, 312, 455, 459, 520, 
593, 597. 
Dolomitic limestones of the laconic 
and metamorphic rocks, 425, 431, 
441 - 464. 
Drift division, 2-4, 158. 
— composition of, 160. 
Drift and upper drift, 130, 156. 
— discussion of its origin, 216 - 228. 
— hills and valleys, 226. 
— grooves and scratches, 136, 198 - 
211, 431, 447, 569. 
— tables of, 199. 
— of New-York island, details, 581 
-604. 
— hills and valleys, 160 - 162. 
— overlies the tertiary of Long island, 
248, 250. 
— and its synonims, 156. 
— summary of conclusions, 228. 
— topographical features, 160. 
— deposits of, accounted for, 223, 
225. 
— supplementary remarks, 636, 637. 
Drifting sands, 30, 32, 233. 
— mode of arresting, 31. 
— origin, 31. 
Drift wood, 295. 
Drowned meadow beach, 27. 
Drowned lands of Orange co. 16, 466. 
— of Columbia co. 15. 
Dykes to protect from inundation, re¬ 
commended, 6, 9, 18. 
Dykes of trap, in white limestone, 
79, 282, 405, 449, note 477, 479. 
— greenstone, 533, 540. 
Dynamics of geology, discussion of 
the drift, 216 - 228. 
£. 
Easlhampton beach, 26. 
Eaton, Prof. 85, 88, 92, 104, 105, 107, 
141, 384. 
Eaton’s neck, alluvial changes, 26. 
Echelon movements of strata, 333,365, 
— masses of strata, 409, 517. 
Echinella, 50, 240. 
Echinellea, 51, 52, 238. 
Economical applications of the meta¬ 
morphic limestones, 444 - 446. 
Edenite, 468. 
Eddy currents, 225, 226, 275. 
Eddies, deposits from, 295, 296, 299. 
Egg shells, lime whence derived, 78. 
Ehrenberg’s communication on infuso¬ 
ria, 48. 
Eights, J. 81, 123. 
Elephant fossil, bones of, in alluvia, 
44, 47. 
Elevation during the quaternary epoch, 
154, 158, 218 272, 629. 
— preceding the Helderberg lime¬ 
stone, 628. 
— of primaiy of Highlands, 288, 628. 
— after the carboniferous epoch, 296. 
— of mountains, 405. 
— of parts of the earth’s surface, 219> 
272. 
Elevatory movements, periods of, 334, 
368, 628-629. 
Ellenville lead mine, 358. 
Emmons, Prof. 124, 129, 152, 153, 187, 
190, 399, 464, 484. 
Emergence of land, effects on our cli¬ 
mate, 296. 
Encrinites, 344, 347, 348, 351. 
Encroachments of the sea, 19. 
Epidote, 481, 536, 577. 
Epochs, geological, 249, 272. 
— of disturbance of the Long-island 
and superior formations, 272. 
— of serpsntine and trappean rocks, 
284, 288. 
— of elevation, 288, 296. 
Epsom salts, 86, 354. 
Equatorial currents, 221. 
Equilibrating currents of the ocean, 
227. 
Equivalency of the Long-island divi¬ 
sion, 272 - 273. 
