SECTION III. Phenomena Common to Stratified

PHENOMENA COMMON TO STRATIFIED AND UNSTRATIFIED BODIES.

p. 97

Chemical agents which produce the decomposition of mineral substances at the surface, § 92, 93. Mechanical agents, § 95, 96. Proofs of wearing from the sea shore, § 97, 98. Rivers, § 99, 100. Defiles among mountains, § 102. Supply of the soil from the decomposition of rocks, § 103. Gravel in the soil, § 104, 105. Gold found in the soil, § 106. Tin, § 107. Proofs of waste from mountainous countries, § 108, 109. Structure of Valleys, § 111. Transportation of stones, § 112. Nearest measure of the waste, § 113. General remarks, § 114, 115. No production of minerals on the surface, § 116. Reproduction at the bottom of the sea, § 117. Continued system of decay and renovation, § 118. Defence against the charge of impiety, 119. Antiquity and order of the revolutions of the globe, § 120, 121, 122, 123, 124. Consistency with the Sacred Writings, § 125. Scope of this theory of the earth distinguishes it from others; beauty and extent of its views, § 126. New facts, § 127. Comparison of this theory with that of Buffon, § 129. Of Lazzaro Moro, § 130. Plutonic system, § 131. Distinguished by the principle of compression, § 132. Explains the oblate figure of the earth, ib. Prejudices against this system, § 133. What may be expected from the progress of science, § 134.

NOTES AND ADDITIONS.

NOTE I.--Origin of Calcareous Earth.

p. 143

Dr Hutton's opinion on this subject accurately stated, § 135. Misrepresented by Kirwan, § 136.

NOTE II.--Origin of Coal.

p. 147

Vegetable origin of coal. Opinion of Buffon, § 137.--of Arduino, ib.--of Lehman, § 138. Distinction attempted between wood coal and mineral coal, § 139. Not of different origin, but gradually pass one into the other, § 140. Bovey coal, § 141. Kirwan derives the matter of mineral coal from the decomposition of hornblende, &c. 143. Absurdity of this supposition, § 144, 145, 146, 147.

NOTE III.--Primitive Mountains.

p. 160

Lehman introduced the term Primitive mountains, § 149. Supposed more ancient than organized bodies, § 150. Stratification of primitive mountains denied by Pini, and maintained by Saussure, § 151.

NOTE IV.--Primary Strata not Primitive.

p. 163

Shells found in primary strata, § 152. Sandstone in primary mountains, § 153. Quartzy sand in the schistus of the Grampians, ib. Rocks distinguished by Werner into three orders, § 154. Objections to this arrangement, § 155.

NOTE V.--Transportation of the Materials of the Strata.

p. 171

The transportation of materials, objected to by the Neptunists, is implied in their own system, § 156, 157, 158. Proofs of great transportation from the animal and vegetable remains, found in rocks, § 160.

NOTE VI.--Kirwan's Notion of Precipitation.

p. 180

Difficulty, of precipitating the materials dissolved in the chaotic fluid, § 162. Insufficiency of the explanation attempted, ib.

NOTE VII.--Compression in the Mineral Regions.

p. 181

Effects ascribed to compression by Newton, compared will the effects ascribed to it in this theory, § 163. Fallacy of Kirwan's argument concerning the fusion of Carrara marble, § 165, 166. Heat of the mineral region may be supported without fuel, § 167. Quotation from Newton's Optics, ib. General remarks, § 169.

NOTE VIII.--Sparry Structure of Calcareous Petrifactions.

p. 190

Sparry and organic structure co-exist in certain fossils, § 171. Sparry and stratified structure co-exist in gneiss, marble, &c. § 172.

NOTE IX.--Petroleum, &c.

p. 194

Petroleum, &c. from the distillation of coal, § 173. Gradation from petroleum to coal often met with, § 174. Connection of amber and coal, § 175. Why mines of blind coal have not always petroleum mines near them, § 176.

NOTE X.--The Height above the Level of the Sea, at which Marks of Aqueous Deposition are now found.

p. 199

These marks consist either in stratification or in marine objects, § 177. The marks of stratification observed, 14739 feet above the sea, § 178. Shells in Peru, 14190, § 179. Kirwan's mistake concerning these shells, § 180. His error similar to VOLTAIRE'S, § 181.

NOTE XI.--Fracture and Dislocation of the Strata.

p. 204

Slips, § 182. Rib of limestone in a slip near Huddersfield, § 183, 184. Singular fracture of pudding-stones at Oban in Argyleshire, § 185. Similar phenomena observed by Saussure between Nice and Genoa, ib. Remarks on it, § 186.

NOTE XII.--Elevation and Inflection of the Strata.

p. 209

Junction of primary and secondary strata, § 187. Breccia incumbent on the primary, § 188. Junction of the primary and secondary strata: At Torbay in Devonshire, § 190,--coast of Berwickshire, § 191,--Cullen in Banffshire, § 193,--Ardencaple in Dunbartonshire, Arran, &c. § 194,--Pembrokeshire, § 195,--Jedburgh, § 196,--Ingleborough in Yorkshire, § 197,--Cumberland, § 198. Inflection of the strata, § 199. Remarkable instances in the Alps and Pyrenees, § 200, 201,--on Ben-Lawers in Perthshire, § 202,--coast of Berwickshire, ib.--Plymouth, § 203. Strata suffering such inflections have been soft and ductile, § 204. General property of these inflections, § 205, 206. uniform stretch of the primary strata, § 207. Inferences as to the nature of the elevating force, § 208. Imperfection of other theories. Crystallisation, ib. Marks of undulæ in the schistus, § 209. Elevation of the strata a stronghold of the Huttonian theory, § 210. Elevation of the strata enables us to see far into the interior of the earth, § 211.

NOTE XIII.--Metallic Veins.

p. 239

Specimens of native iron, § 212, 213. Margraaf's specimen, § 214. Kirwan's hypothesis, § 215. Increase of the specific gravity of native gold by fusion, no argument against its igneous origin, § 216. Specimens of gold and silver shooting through quartz, an argument in favour of the Huttonian theory, § 218, 219. Proof in favour of the same from chalcedony including calcareous spar, § 220. Matter that fills veins not from above or from either side, § 221. Opinion of the Neptunists, § 222. Supposed fact that veins are less rich as the depth increases, § 223. No marks of horizontal deposition in veins; their coating differs from stratification, § 224. Neptunists appear to be misled by the term Stratification, § 225, 226. Veins heave or shift one another, § 227. Vast force employed for that purpose, § 228. Veins of different formation, § 231. Pieces of rock insulated in veins, § 232. Supposition that veins have been filled by infiltrations, absurd, 233. Lenticular veins, and Pipe veins, § 234.

NOTE XIV.--On Whinstone.

p. 260

Whinstone, neither of volcanic nor aqueous formation, § 235. Zeolite and carbonate of lime included in whinstone, but not in lava, ib. Not introduced by infiltration, § 236. Disposition of whinstone mountains differs from that of streams of lava, § 237. This argument first employed by Mr Strange, § 238. His general views of this subject, § 239. Explanation of the regular structure of whinstone hills, according to Dr Hutton's theory, § 240. Many hills supposed to be extinguished volcanoes, are rocks of real whinstone that has flowed deep under the surface. Vein of whinstone mistaken for a stream of lava by Faujas, § 241, 242. Submarine volcanoes of Dolomieu, § 243. Objections to this theory, § 244, 245. Dolomieu in another place contends for the aqueous formation of basaltes, § 246. His arguments answered; also those of Bergman, § 248, 249. Argument of WERNER for the aqueous origin of basaltes, § 250. Remarks on the supposed gradual transition of basaltes to argillaceous schistus, § 251, 252. Of the shells said to be found in basaltes, § 253. Instances from Portrush in Ireland, and from Cerigo on the Coast of Greece, ib. and 254,--from the Veronese, § 255. Objections to the Neptunian formation of whinstone, founded on the difference between it and the contiguous stratified rocks, § 256. On the resemblance of the strata below and above certain masses of whinstone, § 257. On the irregularity of the thickness of those masses, § 258. Wedge form masses of whinstone included between strata, § 259. Consequences of this wedge form, § 260. Sandstone fragments included in whin, § 261, 262. Bending of the strata contiguous to whinstone, § 264. Induration, § 265, 266. Charring of coal by whin, § 267. Of the manner in which the bitumen may have been driven off by heat, § 268. Two kinds of fossil coke, § 269. Graduation into plumbago, ib. and 270. Only remaining objection obviated by Sir James Hall's experiments, § 271.

NOTE XV.--On Granite.

p. 307

Granite veins of two kinds, § 274. Veins Of which the communication with large masses of the same stone is not visible: At the Isle of Coll in the Hebrides, § 275,--at Portsoy, § 276,--in Cornwall, § 277,--in Glentilt, § 278. Veins visibly connected with larger masses. Argument furnished by them in favour of this theory, § 279, 280. Impossibility of their being formed by infiltration, § 281. Veins of this kind in Arran, § 282,--Galloway, § 283,--sides of Loch Chloney, Invernessshire, §284,--St Michael's Mount, Cornwall § 285. Fragments of schistus contained in granite, § 287.

2. Granite of Portsoy.

p. 320

Description of this granite, § 288. Pierre graphique of M. Patrin not perfectly the same with that of Portsoy, § 289. Quartz crystallized in the pierre graphique, § 290. Instances of quartz crystallized in other granites. In that of St Agnes in Cornwall, § 291. Whether this crystallization is only found in secondary granites, § 292.

3. Stratification of Granite.

p. 326

Question stated concerning the stratification of granite, § 293. Remarkable examples of stratified granite at Chorley Forest, Leicestershire, and at Fassnet Water in Berwickshire, § 295. Stratification of Mont Blanc, and the Aiguilles of Chamouni maintained by Saussure, § 296, 297. Seems nevertheless doubtful, § 298. In the granite mountains of Arran doubtful; § 300. Explanation of the stratification of granite in this theory, § 301. If granitic veins were found proceeding from real granitic strata, they could not be explained on the principles here laid down, § 302. No such veins have been discovered, § 303. Answer to an objection made to the igneous origin of granitic mountains, § 304, 305. Of the proportion of the earth's surface occupied by granite rocks, § 306. Not exceeding a ninetieth part, § 307, 311. Extent of granite in Scotland erroneously estimated by Dr Hutton, § 312. Amounts perhaps to a twenty-fourth of the whole surface, § 313. Observations on Mr Kirwan's opinion, § 314.

NOTE XVI.--Rivers and Lakes.

p. 350

The rivers have hollowed out the valleys, § 315. Illustration from the course of the Danube, § 316. Courses of many rivers retain marks of having consisted of a series of lakes, § 317, 318. Filling up and draining of lakes, § 320. Instances from the lakes in Cumberland, § 321. Lake of Geneva, § 322. Lakes in North America, ib. Cataracts, § 323. Difficulties in explaining the generation and continuance of lakes exemplified in that of Geneva, § 324. Attempt to resolve these difficulties, § 325, 326, 327, 328. All lakes not equally subject to them, § 329. Wasting of the land by the rivers, proved from the mouths of rivers on bold coasts, § 330. Examples from Cornwall, § 331.

NOTE XVII.--Remains of Decomposed Rocks.

p. 371

Plain of Crau, § 334. Its gravel from the decomposition of pudding-stone, § 385. Same true of much of the gravel in this island, § 337, 338. Mount Rigi in Switzerland the remains of a body of pudding-stone, § 339. Measure of the destruction in the stratified rocks sometimes, afforded by the unstratified, § 340, 341. Rate at which the elevation of mountains has been supposed to decrease, § 342.

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

Relative level of the sea and land subject to change, § 388. Proofs that it has sunk, on the shores of this island, § 389,--on the coasts of France and Flanders, § 390, 391,--on the shores of the Baltic, § 392. This has not arisen from the depression of the sea, but from the elevation of the land, § 393, 394. The surface of the Hadriatic higher now than formerly, § 395, 396. Also of the Mediterranean, § 398. Irregularities in these changes, § 399, 400. Hypothesis of Frisi, that towards the equator the sea is every where rising, § 401. Disproved, ib. Conclusion, § 402.

NOTE XXII.--Fossil Bones.

p. 458

Vegetable and animal remains contained in the fossil kingdom, § 403. Of those that are enveloped or penetrated with calcareous earth, § 405, 406. Of the bones buried in the loose earth, § 407. Bones in Siberia referred to the rhinoceros and the elephant, § 408. Those on the Ohio doubtful, § 408, 409. Opinion of Camper, § 410.--of Cuvier, § 411. Objections to the latter, ib. Enumeration of five species of animals now extinct, § 412. Change in the animal, and vegetable kingdom may account for bones found in countries where no analogous species now exists, § 414. Proofs that the animals whose bones are found in Siberia inhabited that country, § 415-417.

NOTE XXIII.--Geology of Kirwan and De Luc.

p. 477

These authors have improperly drawn religion into their quarrel with Dr Hutton, § 419. De Luc writes a history of what befel the earth before the creation of the sun, § 420. Remarks on Kirwan's geological writings, § 422, 423, 424, 425.

NOTE XXIV.--System of Buffon.

p. 483

In what Buffon's theory of the earth and Dr Hutton's agree, and in what they differ, § 426, 427. Great merit of Buffon, notwithstanding his errors, § 428.

NOTE XXV.--Figure of the Earth.

p. 488

Physical cause of the earth's oblate figure not obvious from its present condition, § 429. How explained by the Neptunists, § 430. Examination of their solution, § 431, 432. Contradiction implied in it, § 433. Insufficiency of Buffon's explanation, § 434. Of the principle on which the oblateness of the earth may be accounted for in Dr Hutton's theory, § 435. Of the changes that would happen in the figure of a terraqueous body like the earth, supposing it ever so irregular, § 436, 437, 438. Two different causes of change, ib. Ultimate figure, that by which the causes of change are best resisted, § 439. Spheroidal figure, never perfectly acquired, § 440. Agreement of this theory with observation, § 441. Probable extension of the system of waste, and renovation to the other planets, § 442, 443. Confirmation from the system of Saturn, § 444, 445.

NOTE XXVI.--Prejudices relating to the Theory of the Earth.

p. 510

Alleged by some that a theory of the earth ought not at present to be attempted, § 446. The quick succession of geological theories has partly arisen from their object being misunderstood, § 447. A succession of theories is often a continued approximation to the truth, § 448. The more various the phenomena of any class, the greater the chance of discovering their true cause, § 449. Reason to think that the leading facts in geology are now known, § 450, 451. A tendency may be observed in geological systems to approach to one another, and to the Huttonian, § 452. Example from that of Saussure, § 453,--of Dolomieu, § 454, 455. The discoveries of Dr Black were necessary for understanding the true theory of the earth, § 457. Use of theory in matters of observation, § 458, &c.

ILLUSTRATIONS, &c.

A VERY little attention to the phenomena of the mineral kingdom, is sufficient to convince us, that the condition of the earth's surface has not been the same at all times that it is at the present moment. When we observe the impressions of plants in the heart of the hardest rocks; when we discover trees converted into flint, and entire beds of limestone or of marble composed of shells and corals; we see the same individual in two states, the most widely different from one another; and, in the latter instance, have a clear proof, that the present land was once deep immersed under the waters of the ocean. If to this we add, that many masses of rock, the most solid and compact, consist of no other materials but sand and gravel; that, on the other hand, loose gravel, such as is formed only in beds of rivers, or on the sea shore, now abounds in places remote from both: if we reflect, at the same time, on the irregular and broken figure of our continents, and the identity of the mineral strata on opposite sides of the same valley, or the same inlet of the sea; we shall see abundant reason to conclude, that the earth has been the theatre of many great revolutions, and that nothing on its surface has been exempted from their effects.

To trace the series of these revolutions, to explain their causes, and thus to connect together all the indications of change that are found in the mineral kingdom, is the proper object of a THEORY OF THE EARTH.

But, though the attention of men may be turned to the theory of the earth by a very superficial acquaintance with the phenomena of geology, the formation of such a theory requires an accurate and extensive examination of those phenomena, and is inconsistent with any but a very advanced state of the physical sciences. There is, perhaps, in those sciences, no research more arduous than this; none certainly where the subject is so complex; where the appearances are so extremely diversified, or so widely scattered, and where the causes that have operated are so remote from the sphere of ordinary observation. Hence the attempt! to form a theory of the earth are of very modern origin, and as, from the simplicity of its subject astronomy is the eldest, so, on account of the complexness of its subject, geology is the youngest of the sciences.

It is foreign from the present purpose to enter on any history of the systems that, since the rise of this branch of science, have been invented to explain the phenomena of the mineral kingdom. It is sufficient to remark, that these systems are usually reduced to two classes, according as they refer the origin of terrestrial bodies to FIRE or to WATER; and that, conformably to this division, their followers have of late been distinguished by the fanciful names of Vulcanists and Neptunists. To the former of these Dr Hutton belongs much more than to the latter; though, as he employs the agency both of fire and of water in his system, he cannot, in strict propriety, be arranged with either.

In the succinct account which I am now about to give of this system, I shall consider the mineral kingdom as divided into two parts, namely, stratified and unstratified substances I shall treat, first, of the phenomena peculiar to the stratified; next, of those peculiar to the unstratified; and, lastly, of the phenomena common to both. Beginning, then, with the first, the subject naturally divides itself into three branches; viz. the materials the consolidation, and the position of the strata.