NOTE XVIII.--Transportation of Stones, &c. p. 381 Gravel smaller and rounder the farther from its native place, § 343. Different sources of _caillou roulés_, § 344, 345. Stones that have begun their migration before the cutting out of the present valleys, § 346. Declivity necessary to enable stones to travel from the top of Mont Blanc to the top of Mont Jura, § 347. Granite from Mont Blanc found eastward in the valley of the Drance, § 348. Machinery employed by nature in transporting rocks, § 349, 350. Instances of transported stones of great size,--from the vicinity of Geneva, § 351, 352,--from the Isle of Arran, 353. How gravity may contribute to the moving of large stones, even when the declivity is small, § 354. Rocking-stones, § 355. Stone in Borrowdale,--in the valley of Urseren, § 356. Large stones are sometimes the remains of veins, § 357. Of the hypothesis of a _debacle_, § 358. Structure of valleys unfavourable to this hypothesis, § 359, 360. Particularly of valleys close at the ends, § 361, 362. Whether the supposition of a _debacle_ is necessary to explain the moving of large masses of rock, § 364. Whether the abrupt faces of hills indicate the existence of any sudden torrent, &c. § 365. Fact concerning the steep faces of the mountains in the south of Africa, § 366. A fact stated that would lead necessarily to belief in a _debacle_; no example of it has yet occurred, § 367. NOTE XIX.--Transportation of Materials by the Sea. p. 413 Of the manner in which the _detritus_ of the land is spread out over the bottom of the sea, § 369, 370. Seas rendered shallower, § 371. Sand banks, § 372. Great system of currents traced in the Atlantic, § 373, 374. How far this transportation of materials may affect the earth's diurnal motion, § 376, 377. Kirwan's misapprehension of Frisi, and of Major Rennell, § 378, 379. His mistake about the tides, § 380, 381,--and about the formation of sand banks, § 384. NOTE XX.--Inequalities of the Planetary Motions. p. 437 These inequalities all periodical, § 385. Circumstances on which this depends, § 386. Affinity of this conclusion to that which Dr Hutton has established with respect to the changes at the surface of the earth, § 387. NOTE XXI.--Changes in the Apparent Level of the Sea. p. 441