PAGE

MARINE DEPOSITS

322

Raised Beaches

322

Recent Marine Deposits

323

Burtle Beds, &c.

323

Shingle Beaches .

324

Chesil Bank

. 324

ALLUVIAL DEPOSITS

326

Alluvium, Brickearth and Gravel-Lancashire-South-

west of England, &c.—Romney Marsh-Holderness-

Fenland, &c.—Copford, Clacton, &c.—Thames Valley

-Geology and Archæology, Flint Implements, &c. 326

CHAPTER XI.

Sub-aðrial Phenomena.

338

SPRINGS. Mineral Springs—Thermal Springs

338

SWALLOW HOLES

344

TUFA

346

CAVERNS. Stalactites and Stalagmites

347

LANDSLIPS.

352

ÆOLIAN OR BLOWN SANDS

354

SUBMARINE FORESTS

355

PEAT

Soils. Warp and Trail-Clay-with-Flints-Mould—Terraces , 359

GREY WETHERS

363

357

CHAPTER XII.

IGNEOUS AND METAMORPHIC ROCKS-MLVERAL VEINS.

Classification of Igneous and Metamorphic Rocks, by F. Rutley-General

account of Igneous and Metamorphic Rocks

. 365

MINERAL VEINS. Iron Oros-Lead Ores-Zinc Ores-Copper Ores—Tin

Ore-Gold-Manganese Ores—Plumbago

382

CHAPTER XIII.

DENUDATION AND SCENERY.

Causes and Effects of Denudation-Coast Line-Islands-Inland Features

-Hills—Vales-Plains--Plains of Marine Denudation- Escarpments

- River Valleys-Escarpments and Cliffs-Denudation of Weald-

Lakes—Waterfalls, Cheddar Cliffs-Weathering of Limestone—Tors,

Logan Stones, &c.-Forests_Influence of Man .

387

NOTES ON FEATURES OBSERVABLE ON THE MAIN LINES OF RAILWAY. Great

Eastern Railway-Great Northern Railway–Midland Railway-

London and North-Western Railway-Great Western Railway-

London and South-Western Railway, &c.

413
CHAPTER XIV.

GEOLOGY IN THE FIELD- ITS ECONOMIC AND SCIENTIFIC

BEARINGS-CONCLUSION.

PAGB

Petrological or Structural Features—Faults and Disturbances--Economic

Bearings of Geology-Scientific Bearings of Geology- Darwinian

Theory-Antiquity of Man-Conclusion

420

APPENDIX.

.

A. Glossary of Terms and Addenda

437

B. Synopsis of the Animal Kingdom with especial reference to Fossil

Forms.

443

C. List of the principal Works consulted

451

D. Bibliography

453

INDEX

455

EXPLANATION OF MAP.

As the Map accompanying this volume differs in some respocts from other
geological maps of England and Wales, it may be well briefly to indicate the
changes introduced.

The index of colours has been arranged to show the comparative thicknesses
of the formations.

The Cambrian and Silurian rocks are classified according to Sedgwick, so
that the former group includes the Lower Silurian of Murchison.

The Devonian rocks are shown in the index as representing portions of both
Old Red Sandstone and Lower Carboniferous Rocks, which seoms to be their
true position in the geological scale.

The Neocomian (Wealden and Lower Greensand) or Lower Cretaceous
strata are separated from the true or Upper Cretaceous strata.

The Drift deposits (Boulder Clay and Gravels) which it is attempted to
show, comprise a very small portion of those which are scattered over the greater
part of the country; but as yet they have been mapped only in certain
areas where they are perhaps most extensively developed, and these areas are
shown. It must be remembered, however, that while they obscure so much of
the Chalk and Tertiary strata in the Eastern counties, these older deposits are
generally exposed in the valleys, although in tracts too small to display them
upon the Map.

LIST OF WOODCUTS.

FIG.

PAGE

1. General Section of Malvern

21

2. Penrhyn Slate Quarry .

29

3. Section of Cader Idris

39

4. Section from Mickle Aw Fell to Murton Pike, Lake District .

41

5. The Gorge of Borrowdale, between the Bowder Stone and Castle

Crag.

42

6. Section of Snowdon

44

7. Section of Old Red Sandstone on the north-west escarpment of the

Black Mountains on the borders of Herefordshire

64

8. Section across the Mendip Hills.

84

9. The Idol Rock, Brimham. Pulpit Rocks to the right

90

10. The Peak Table-land, Derbyshire

91

11. General section across the Derbyshire and Yorkshire Coal-field 100

12. Section from Dartmoor to Great Haldon