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THE 
 
 GREAT STONE BOOK 
 
 NATURE. 
 


 
 THE 
 
 GREAT STONE BOOK 
 
 ATUKE. 
 
 BY 
 
 DAVID THOMAS ANSTED, M.A. 
 
 F.R.S., F.Q.S., ETC. 
 
 LATE FELLOW OF JESUS COLLEGE, CAMBRIDGE; HONORARY FELLOW OF KING'3 
 COLLEGE, LONDON. 
 
 PHILADELPHIA : 
 GEORGE W. CHILD S, 
 
 628 & 630 CHESTNUT STREET. 
 
 1863. 
 
. 7- 
 
 EARTH 
 SCIENCES 
 
 LIBRARY 
 
 o 
 
 PHILADELPHIA. 
 
 \ 
 
 / 
 
CONTENTS. 
 
 $tttmbmJ0rg Chapter, 
 
 THE BOOK OF NATURE. 
 
 Nature a Library rather than a Book Unity of Method in Creation Infinite 
 Resources of Nature Extent to which the Plan of Nature is made out The 
 Study of the " STONE BOOK" What it means Necessity of studying the Lan- 
 guage of Nature to understand the Book Meaning of Geology The Language 
 of Geology a Picture-Language Facilities for observing in Geology Method 
 of Nature illustrated from Astronomy Familiar Causes of Geological Pheno- 
 mena The First Lessons to be learnt Quarries and Cuttings not indis- 
 pensable Page 21 
 
 PAKT THE FIEST, 
 THE LANGUAGE OF THE GREAT STONE BOOK. 
 
 THE RIVER-BED AND THE SEA-BEACH. 
 
 THE RIVER Its first Traces and subsequent Course Passage through the Plains 
 Approach to the Sea Cause of the unfailing Supply of Water The Water 
 muddy after Rain Reason of this The Bed of the River How occupied 
 Passage of a River through a Lake, and the Result General Result at the 
 Mouths of large Rivers Illustration in the Case of the Mississippi THE SEA- 
 BEACHHOW it differs from the River-bed Formation of a Pebble-beach^- 
 Effect of Stones rubbing over each other Incessant Motion of the Water 
 owing to Tidal Action The General Circulation of Water through the Earth 
 the Cause of the Incessant Wearing of the Surface .............................. 35 
 
 1* 5 
 
CONTENTS. 
 
 cr 
 
 THE SUN, THE WIND, THE RAIN, AND THE FROST. 
 
 Result of Drought in cracking the Earth Subsequent Rain splitting and 
 removing large Fragments Effect of Winter, Rain, and Frost The Effect 
 chiefly seen where there is little Cultivation Effect on an exposed Coast 
 Effect of Ice Formation of Glaciers Removal of Stone by Glaciers Limit 
 of Glacier Action-^Effect of Wind on loose Sand Effect of Lightning The 
 Destruction of the Surface perpetual Incessant Alternation of Heat and 
 Cold Direct Action of Rain and Frost Total Amount of Change thus 
 Caused Rocks The different Varieties ......................................... Page 47 
 
 PAET THE SECOND, 
 THE STONES OF THE GREAT STONE BOOK. 
 
 CLAY AND ITS VARIETIES. 
 
 What is meant by Clay Its Origin ALUMINIUM Alumina Forms in which 
 Alumina is known Its Combination with Silica to form CLAY Clay always 
 mixed with Water and foreign Impurities Properties of Clay Production 
 of Brick Various Kinds of Brick-clay Fire-clay Its Composition and Use 
 Terra-cotta How formed Its Advantages and Disadvantages Potter's- 
 clay Where obtained, and how used China-clay Its composition Whence 
 obtained How and where used Floating-bricks and Bath-brick Fuller's- 
 earthIts Nature and Use Lias Its peculiar Properties Alum-clay Its 
 Use Rarity of Fossils in some Clays Drainage of Clay-lands Artesian 
 Springs beneath Clays Curious Remains of Cuttle-fish and other .Animals in 
 Clays Remains of Reptiles Fragments of Vegetation Fruits at Sheppy 
 Chief Deposits of Clay in England Characteristics of each SLATE Its Nature 
 and Uses Origin of Slate Contents of Clay Rocks Felspar a Variety of Clay 
 Lava and Pumice of the same Nature Precious Stones derived from Clay 61 
 
 (Soapier % cfowrt^. 
 
 CHALK. 
 
 The Surface and Landscape in a Chalk District Features of the Chalk in the 
 British Islands The characteristic Peculiarities of Chalk as a Rock Its 
 Contents Its Identity with deep-sea Mud, or Oaze Its Dissimilarity to other 
 Limestones Its probable Origin Flints in the Chalk Their Position and 
 
CONTENTS. 7 
 
 Form Frequent Association with Fossils How produced originally Bed- 
 ding of Chalk Beds often disturbed Chalk-cliffs of the South Coast Chalk 
 in France Accumulations of Material covering parts of the Chalk Portions 
 of the Chalk often removed Texture of Chalk Its Water-content Uses of 
 Chalk, for Building, for Lime, and for dressing Land The History of Chalk 
 and Flint Occasional but rare Occurrence of foreign Substances in Chalk 
 Chalk a good Starting-point for the Young English Geologist ... Page 78 
 
 Chapter % $ iftjy. 
 
 LIMESTONES AND MAKBLE. 
 
 Limestones differ from Chalk in being more Crystalline Passage of Limestone 
 into Marble Limestone only occasionally present on the Earth Its Valuo 
 as a Rock Varieties of Limestone Carbonates of Lime (Limestones Proper) 
 Carbonates of Lime and Magnesia (Magnesian Limestones) and Sulphates 
 of Lime (Gypsum) Marbles Oolites Bedding of Limestones Limestones 
 in the Quarry Quarries Picturesque Objects Underground Quarries 
 Caverns in Limestone Stalactites and Stalagmites in Caverns Bone-contenta 
 of Caverns Human Remains in Caverns Cliff-scenery of Limestone-rock in 
 Derbyshire and elsewhere Beds of Limestone Valuable Minerals found in 
 Limestone Composition of ordinary Limestone compared with that of Chalk 
 "Work of the Coral Animal Position and Locality of Limestone-rock and 
 Marble Sulphate of Lime, Gypsum and Alabaster Position as Rocks Lo- 
 calities Uses Phosphate of Lime Coprolites General Conclusion concern- 
 ing Limestones 91 
 
 % 
 
 SAND AND SANDSTONE. 
 
 Universality of Sand Gold Sands Their Wide Range Silica Sands Nature 
 of Silica Varieties of Silica commonly found Flints ^Their Nature and 
 Composition Appearance under the Microscope Uses of Flint Flint com- 
 mon in Chalk, and other Forms of Silica in other Limestones Sandstone 
 Varieties of Sandstone Their Uses Flagstones Footprints and other 
 Markings on Sandstone Their Origin Abundance in certain Districts The 
 Animals that have made these Markings Sandstones of this kind rarely 
 good for Building Salt in Sandstone Deposits Gypsum found with Salt in 
 Sand Bitumen and Asphalte in Sand-rocks Use of Sandstone in allowing 
 Water to percolate Fossils found with Sand-rocks Minerals in Sandstone 
 and Quartz Gold Sands Quartz Rocks and their Appearance General 
 Barrenness of Quartz Sands and Rocks 106 
 
8 CONTENTS. 
 
 Chapter 
 
 GRANITE, GRANITIC ROCKS, AND LAVA. 
 
 Varieties of Stone not yet treated of Where Granite is best seen and studied 
 Reefs and Detached Rocks and Islands Cliifs Color as well as Form 
 of Granite peculiar Rounded Mountains and Pyramidal Peaks of Granite 
 Granite in Egypt Buildings of Granite sometimes almost indestructible 
 Natural Cliffs of Granite sometimes rapidly worn Composition of Granite 
 Principal Varieties Granite Veins Their Contents Granite in principal 
 Mountain-Chains Porphyry In what it differs from Granite Extreme 
 Hardness of Porphyry Lava Its Nature Basalt Where chiefly found 
 Properties Gneiss and Schists Rotten Granite Picturesque Examples of 
 decomposed Granite in Bavaria Page 121 
 
 PAET THE THIRD, 
 
 THE PLACEMENT AND DISPLACEMENT OF 
 THE STONES IN THE GREAT STONE BOOK. 
 
 % 
 
 IN THE BRICK-FIELD AND THE GRAVEL-PIT. 
 
 Links connecting the Present with the Past The ordinary Means at Hand to 
 determine such Links sufficient Brick Clay How associated Mixed with 
 Sand Supposed to be the Result of a Deluge Section of a Brick-pit Con- 
 dition of a Gravel-pit Marine Shells and similar Fossils found with Gravel 
 Effects of Water Large Districts recently under Water Effect of Tor- 
 rents of Water or Deluges Long Duration of Causes producing Diluvial 
 Appearances Earthquake Action insufficient to account for a Deluge Time 
 required History of a Pebble ........................................................... 135 
 
 IN THE QUARRY AND THE MINE. 
 
 Quarries almost universally accessible All Kinds of Stone are quarried 
 Magnitude of Quarries Points of Interest in Quarries What Lessons will 
 be inculcated in this Chapter Nature of Material quarried Granite Quarries 
 Only some Portions of the Stone workable Reason why there is so much 
 Difference in Quality Joints and Systems of Cracks Veins penetrating the 
 Mass of Stones Frequent Improvement of Quality of Stone in descending 
 
CONTENTS. 9 
 
 Slate Quarries Their Points of Interest Facility of Splitting, or Cleavagz, 
 that characterizes Slate The Sets of Joints LimestmeQuarries Varieties of 
 Limestone Joints in Marble and Limestone Different Kinds of Limestone 
 quarried Limestone generally much broken near the Surface Fossils com- 
 mon in certain Beds Sandstone How bedded Marks of Bedding Joints 
 Basalt Picturesqueness of Quarries in this Rock Columnar Character 
 of the Rock Proof of Igneous Origin of Basalt General Result of the 
 Examination of Quarries Under-ground Quarries at Caen Mining is a kind 
 of under-ground Quarrying Mines generally Mining for Coal Mining in 
 Mineral Veins for Metals and Ores Systems of Mineral Veins Example in 
 Cornwall Right-running Veins and Cross-CoursesGeneral Summary of the 
 Lessons learned in Quarries and Mines Page 151 
 
 CIrapter % 
 
 VOLCANOES AND EARTHQUAKES. 
 
 Volcanic Mountains Their Conical Form Nature of the Eruptions from them 
 Examples of Ancient and Recent Eruptions Elevations at which Eruptions 
 may take place in no way limited Distribution of Volcanoes in Groups in 
 different Parts of the World Volcanoes now extinct Universal Proof of the 
 Reaction of the Interior of the Earth on the Surface Interior of Africa and 
 Australia less Volcanic than other Countries Hot Springs and other Proof 
 of High Temperature at a Small Depth History of a Volcanic Eruption Noises 
 Outbursts of Gas and Steam with Sulphur Slight Shocks and Tremblings 
 of the Ground Eruption of fine Ashes and Dust Lava Nature and Amount 
 of this Substance poured out Little Difference in the Nature of Volcanic 
 Products What Volcanoes indicate Earthquakes Meaning of the Pheno- 
 menonDuration of an Earthquake Range of a Single Disturbance Extent 
 of the Earth's Surface sometimes disturbed Periods when Earthquakes 
 chiefly occur More Earthquakes in Cold than in Warm Weather Changes 
 of Level accompanying Earthquakes Examples in America and India- 
 Upheavals in the Absence of Earthquakes Scandinavian Coast known to 
 undergo Changes of Level Raised Beaches in various Places Importance 
 of recent Changes Laws and Theories of Earthquakes 163 
 
 r 
 
 THE DISTURBANCE OF ROCKS. 
 
 Order observable in Stratified Rocks Appearance of Stratified Rocks illustrated 
 by the Piling of Books^ General Irregularity of the Placing Most of the 
 Rocks are Slanted The Railroad from London to Brighton The Sequence 
 of the Rocks observed, and their Meaning Disruption of the Chalk- -More 
 
10 CONTENTS. 
 
 complicated Examples of Tilted Rocks Further Disturbances indicated- 
 General Result of Travelling across England Order of -the Rocks sometimes 
 disturbed The Reason of this Detached Portions of Rocks Extent and 
 Range of similar Deposits in various Countries Australia and Africa con- 
 trasted with England Complications of Rocks in Mountain-Districts Con- 
 version of one Rock into another under such Circumstances Great Disturb- 
 ance involved Upheaval of the Great Mountain-Chains The Himalayan 
 Chain and the Alps The Andes Older but Lower Mountain- Axes Results 
 of Upheaval on the Rocks Special Language employed by Geologists in 
 describing such Phenomena Explanation of Terms Dip and Strike of Rocks 
 Faults Anticlinal Axis Conformable and Unconformable Stratification 
 Granite the Central Rock of Mountain-Axes Granite formed at Great Depth 
 Derivation of Metamorphic Rocks Catastrophes not necessarily involved 
 in these Changes Objection to assuming that the Changes that have taken 
 place have involved a.System of Interferences Page 181 
 
 PAET THE FOURTH, 
 THE PICTUKES IN THE GREAT STONE BOOK. 
 
 WHAT THE PICTURES ARE, AND WHAT THEY MEAN. 
 
 Necessity of Time in explaining Elevation of Rocks Contents of Rocks- 
 Petrifactions, or Fossils Mode in which Organic Substances may be pre- 
 served Organic Remains The Pictures in the Stone Book Abundance of 
 Remains of Life What Parts are likely to be buried safely Small Pro- 
 portion of the Whole that can thus be presented for Examination Great 
 Variety really found in spite of the Causes of Destruction Further Illus- 
 tration of the Use of Fossils by a Number of Books Real Value of the 
 Geologic Record Simplest Forms of Organization indicated in a Fossil State 
 Sponges found fossil in various Deposits Vegetable Remains found in 
 Coal and the adjacent Rocks Corals frequently indicated by their actual 
 stony Skeletons Peculiarities of Form of the earlier Corals Stony Parts 
 of Star-fishes and Sea-urchins Curious Habits of some of these Animals 
 assist in the Dispersion of their Remains Indications of Worms and Insects 
 and of Crabs and Lobsters not rare Bivalve and Univalve Shells Remains 
 of Fishes and peculiar Structure of such Animals favorable for Preserva- 
 tion Reptiles, Birds, and Quadrupeds Circumstances under which Remains 
 of Quadrupeds might be retained ...................................................... 199 
 
CONTENTS. 11 
 
 Chapter % Cfci 
 
 ANCIENT FORESTS AND MODERN FUEL. 
 
 The Chain of Mineral Fuel through England Coal Scenery Visit to a Coal- 
 mineImpression made on the Visitor The Floor of the Mine The Root- 
 lets of Trees in the Floor Absence of Under-clay in some Coal-fields Coal 
 very regular in some Countries Coal the Remains of Ancient Vegetation 
 Microscopic Evidence of the Origin of Coal Coal Strata and its Fossils 
 Abundance of Ferns indicated Trunks of Trees Appearance of an ancient 
 Forest of the Coal Period Principal Varieties of Trees The Siffillaria, or 
 Scarred-trunk Tree-fern Its Appearance and Chief Characteristics The 
 Roots (Stigmarise) and their Peculiarities The Lepidodendron an ancient 
 Arborescent Club-moss The Calamite: its Nature and Peculiarities Tree- 
 ferns very common Insects found in the Coal-beds Origin of Coal Differ- 
 ences between Wood and all kinds of Coal Multiplication of Beds of Coal 
 on the same Spot Upheaval of Coal Deposits How Coal Forests can have 
 grown in Northern Climates Climate required Possible Alteration of 
 Northern Climates by Changes in the Land Former Archipelago probable 
 
 Enormous Quantity of Vegetation needed to produce a Bed of Coal Origin 
 of Coal Prospect of continued Supplies ...................................... Page 218 
 
 Chapter % <Jf owrimtilj. 
 
 THE PRE-ADAMITE WORLD. 
 
 Remains of Former Inhabitants of the Earth Ancient Stone Weapons Qf Pre- 
 historic Races Relation of Structure to Habits, the Key to this Part of Na- 
 ttiral History Peculiarities of Structure illustrating this Extinct Species 
 of Animals found among the Fossils The Study and Use of Fossils deter- 
 mine the Order of Stratified Rocks, and enable Geologists to identify them 
 
 Mechanical Illustration of this Mode of identifying Rocks Frequent 
 Omissions in the Series of Fossils Imperfection of the Geologic Record 
 Number and Variety of Objects found Fossil Remains of Man and of the 
 larger Quadrupeds Elephants and gigantic Quadrupeds once common in 
 England The Mammoth Curious and anomalous Forms found in India 
 The Sivathere and others Remarkable gigantic Sloth-like Quadrupeds in 
 South America Gigantic Marsupials in Australia Curious Quadrupeds of the 
 older Rocks Birds in a Fossil State Gigantic Birds of New Zealand Foot- 
 prints of Birds and Reptiles Reptiles Frog-like Reptiles (Labyrinthodori) 
 
 Flying Reptiles (Pterodactyl) Marine Reptiles Ichtliyosaur and Plesiosaur 
 Fossil Fishes, with bony Plates coated with Enamel Fossil Sharks and 
 Rays Fossil Cuttle-fishes Ammonites and Belemnites Bivalve Shells State- 
 ment of the Law that Fossils are characteristic of Formations Kinds of 
 Fossils most useful for this Purpose Vast Profusion of Nature in the Accu- 
 mulation and Distribution of Fossils ................ .................................. 240 
 
12 CONTENTS. 
 
 PART THE PIFTH, 
 THE TREASURES OF THE GREAT STONE BOOK. 
 
 GLITTERING TREASURES OF THE EARTH. 
 
 The Earth contains many beautiful and valuable Objects belonging to the 
 Mineral Kingdom Object of the present Chapter to describe only One Group 
 
 The Gems and their Literature Various Ways of viewing the Subject 
 The DIAMOND Anciently valued for special Purposes Classical Account of 
 its Discovery Diamonds associated with Gold Obtained by Washing Marco 
 Polo's Account of Diamond-finding Brazilian Diamonds Composition of the 
 Diamond Cutting of the Diamond Colored Diamonds Large Diamonds 
 The Pitt Diamond and the Koh-i-noor Uses of Diamonds RUBY and SAP- 
 PHIRE Varieties of these Gems Corundum Greek Name for the Ruby 
 The Ruby phosphoric Remarkable Stones Sapphire; its supposed Value 
 about the Person Used to engrave upon EMERALD Its Properties Large 
 Specimens without Flaw very rare Whence obtained Superstitions con- 
 cerning this Stone Large flat Stones admired in the East Supposed Medical 
 and other Properties BERYL, or Aqua-marine Its Appearance and Proper- 
 ties TOPAZ The Oriental Topaz a Sapphire Varieties of Color and Uses 
 of the Topaz GARNET The Carbuncle a Garnet Color and Properties 
 Hyacinth, Zircon, and other Stones MOONSTONE and other varieties of Felspar 
 
 QUARTZ, and the Gems obtained from it Crystal, a Name for Quartz 
 Cairngorm, Jasper, and Bloodstone Agate, Onyx, &c. and Carnelian Use of 
 the Onyx in Cameos CaVs-eye, and other Combinations of Quartz with Water 
 Cavities in Quartz OPAL Its great Beauty and Value TURQUOISE Its 
 History PEARLS Where and how found Seed-Pearls AMBER How found 
 
 Its Value Medicinal Properties CORAL Found in the Mediterranean 
 Curious Superstitions concerning it Polish Superstitions concerning Gems 
 
 Apostle Gems Jet, Malachite, and Lapis-lazuli Jade The Lessons to be 
 learnt from Gems Their great Beauty and small apparent Use The Use 
 of Beauty .................................................................................. Page 267 
 
 Chapter % 
 
 SOURCES OF METALLIC WEALTH. 
 
 How the Metals are met with Native Metals Ores Noble Metals generally 
 found Native They are comparatively rare GOLD How Discovered Chief 
 Localities Properties of Gold Gold-dust, Pepitas, and Nuggets Suddr 
 
CONTENTS. 13 
 
 Influx of Gold from Time to Time Very wide Range of Gold Gold Leaf 
 and Wire Gold occasionally combined with other Metals Transmutation 
 of Base Metals into Gold Real Quantity of Gold obtained very small, com- 
 pared with the Quantities of other Metals found Value of Gold not facti- 
 tious SILVER Its Appearance Less capable than Gold of resisting Acids 
 Native Silver Common Ores of Silvers-Combinations with Lead and Copper 
 Properties and Uses of Silver Silver a Metal very widely distributed 
 De-silverization of Lead MERCURY A Fluid Metal Amalgam found with 
 Sulphur Uses of Mercury in the Arts Divisions of the Base Metals Mal- 
 leable Group COPPER Its Properties and Peculiarities Its History Occa- 
 sionally found Pure in large Quantities Ores Pyrites and Malachite LEAD 
 Common Ores Galena Properties and Uses of Lead IRON Its History 
 Sources of Supply Properties and Uses TIN Its Uses, History, and Pro- 
 perties ZINC When discovered Very volatile Uses NICKEL Its Value 
 in making German Silver Its Properties COBALT Its Uses Ores usually 
 found ARSENIC ANTIMONY BISMUTH MANGANESE CHROMIUM Rarer 
 Metals Meteoric Stones Metals in the Sun and Stars Page 293 
 
 ilje 
 
 THE CIRCULATION OF WATER. 
 
 The Circulation of Water not necessary to Planetary Existence Universal 
 Distribution of Water near the Earth's Surface Water exists in two ways 
 in Rocks Part of it helps to form all Solids Part fills up the Crevices and 
 Open Spaces in all Rocks This State of Things only kept up by the con- 
 stant Circulation Phenomena of Springs and Wells illustrate this Course 
 of Water in its Circulation Water always in the Air How supplied How 
 lifted into the Air by Evaporation from the Sea Drifted along in Clouds 
 Falling on the Earth in Rain Conveyance along the Surface in Rivers 
 Absorbent Power of Sand and Sandstones, Limestones and Chalk Total 
 Quantity of Water in a given Volume of Rock Electrical Action in the 
 Conversion of Water into Steam The Water that falls as Rain Its Course 
 when it enters the Earth No Repose in Nature Changes that take place 
 in the Earth's Interior Deposit generally as Mud Partial Drying under 
 Pressure Subsequent Depression, and final Re-lifting Results of these 
 Movements Destruction and Denudation when Rocks come again to the 
 Surface Result if the Earth were deprived of Water ............................ 313 
 
 2 
 
14 CONTENTS. 
 
 THE SHUTTINGMJP OF THE GKREAT STONE 
 BOOK. 
 
 Copter % <%(jtttni|j. 
 
 CONCLUSION. 
 
 General View of the History of the World Geology a crmralative Science- 
 No Finality in the Discoyeries Observation of Nature the only Path to 
 Geological Discovery Observation possible to all Extreme Importance of 
 accurate Observation No Mystery in Geology Discovery of Systems and 
 Laws the Kesult of accurate Observation The real Method of Nature may 
 bo ultimately made out Geology the most important Department of Natural 
 History Certainty of Benefit from the Study of Nature in a right Manner 
 The one great Lesson of Geology is to enforce the Necessity of a careful 
 Study of existing Methods of Nature Page 327 
 
EXPLANATORY LIST 
 
 ILLUSTRATIONS. 
 
 I. VIGNETTES. 
 
 THIS Plate represents a group of figures of vertebrate animals such as have 
 existed on the earth at various geological periods. Species are selected that 
 are among the most singular in form and proportions, and also among those 
 whose remains are sufficiently perfect to justify a restoration of the complete 
 animal. The following are the names by which they are known to naturalists, 
 and the deposits in which they are found. They are drawn as nearly as possi- 
 ble to the same scale. Most of the animals are alluded to in Chapter the 
 Fourteenth. 
 
 1. MEGATHERIUM, a Newer Tertiary gigantic Sloth. 
 
 2. PALEOTHERIUM, an Older Tertiary animal like the Tapir. 
 
 3. DINORNIS, a very modern but extinct gigantic Bird. 
 
 4. MEGALOSADRUS, a Middle Secondary gigantic Land Reptile. 
 
 5. PLESIOSAURCS, a Middle Secondary gigantic Marine Reptile. 
 
 6. PTERODACTYL, a Middle and Newer Secondary Flying Reptile. 
 
 7. LABYRINTHODON, an Older Secondary and Paleozoic Frog-like Reptile. 
 
 8. DAPEDIUM, 
 
 9. PTYCHOLEPIS, 
 
 i two Secondary Fishes of the Lias Period. 
 
 oft! 
 
 A sketch illustrating the atmospheric and aqueous forces tending to modify 
 the surface of the earth at present. In this view distant snow-clad mountains, 
 with glaciers in the valleys, are represented in their relation to a river convey- 
 ing the worn material to the ocean. The rocks and cliffs enclosing the river 
 are much more widely separated than seems due to the magnitude of the river. 
 Near the sea the destruction caused by the tidal wave is indicated, and thus in 
 many ways the language of the Great Stone Book is taught. 
 
16 EXPLANATORY LIST OF ILLUSTRATIONS. 
 
 Stones of % ooli. 
 
 The Stones of the Book are indicated by a group of very singular boulders, 
 probably worn by exposure to atmospheric influences generally, rather than 
 by water alone. These large egg-shaped stones have been figured from an 
 American sketch. Similar but more angular boulders are found in various 
 parts of Northern Europe. All rocks are Stones of the Book of the "World, 
 and picturesque scenery in every country may be regarded as exemplifying 
 some one or other of them. 
 
 %\t Jjkttttunt mtb Jisplatxnwnt of % Stones. 
 
 In this diagrammatic sketch are illustrated some of the more striking phe- 
 nomena of the disturbance of rocks. In the background is a volcano, the im- 
 mediate indication of the reaction of the interior of the earth on its external 
 surface. On the right are representations of anticlinal and synclinal axes, 
 faults, and other fractures of strata ; and on the left are examples of conform- 
 able and unconformabk stratification, tilted rocks, and also of the accumulation 
 of debris at the foot of cliffs. 
 
 |)ktas m 
 
 A sketch illustrating some of the more remarkable and better-known varie- 
 ties of tree-vegetation supposed to afford the nearest resemblance to the 
 vegetation of the Coal Period. The tree-ferns, and the curious varieties of 
 palms and pines, characteristic of islands in the South Pacific Ocean, are those 
 that have been chiefly referred to for form and general appearance. The 
 actual shapes, proportions, and markings of the remains of trees, found fossil 
 in our coal-measures, are taken as authorities for the wide divergence from 
 these modern types. Many of the principal forms are described in Chapter 
 the Thirteenth, on "Ancient Forests and Modern Fuel." 
 
 |e feasts of % $)o0k. 
 
 A group of some of the most interesting and picturesque minerals and 
 native metals, drawn from specimens in the possession of Professor Tennant. 
 The following are the references to the Plate : 
 
 1. A mass of small Crystals of Quartz or Rock-crystal of the most usual 
 
 form (see p. 109). 
 
 2. A specimen of doubly-refracting Iceland-spar or Crystalline Carbonate 
 
 of Lime. 
 
 3. A fine Crystal of Emerald in its matrix (see p. 275). 
 
EXPLANATORY LIST OF ILLUSTRATIONS. 17 
 
 4. One of the finest Nuggets of Australian Gold (sec p. 295). 
 
 5. A very beautiful specimen of Capillary or hair-liko Native Silver (see p. 
 
 299). 
 
 6. A specimen of Malachite or Carbonate of Copper, showing the concentric 
 
 structure (see p. 304). 
 
 7. Crystals of Specular Iron Ore, from the Island of Elba (see p. 307). 
 
 8. A Crystal of Galena (Sulphuret of Lead) (see p. 305). 
 
 II. DIAGRAMS. 
 
 PAGB 
 
 Section through an Alluvial Valley 39 
 
 Effects of Ice on the Banks of the Dwina. 56 
 
 The Head of Earth, the Sand, and the Clays in a Brick-pit 137 
 
 Section from London to Brighton 183 
 
 Illustration of " Faults" ~ 192 
 
 Anticlinal and Synclinal Axes 195 
 
THE BOOK OF NATURE. 
 
 " To recount almighty works 
 What words or tongue of seraph can suffice, 
 Or heart of man suffice to comprehend ? 
 Yet what thou canst attain, which best may serve 
 To glorify thy Maker, and infer 
 Thee also happier, shall not be withheld 
 Thy hearing." 
 
 PARADISE LOST, Bk. vii. lines 112-118. 
 
ALL know what is meant by the Book of Nature. 
 But Nature is rather a Library than a Book ; for 
 it is the general and well-stored receptacle of all 
 that has ever been created, of all that we know 
 and all we have not yet learned, of all that is 
 animate and all that is inanimate, of all that is 
 happening and all that has happened, not only 
 on the earth, but above the earth and within it 
 and around it. Nothing once existing has entirely 
 disappeared. Every thing has been photographed, 
 and is preserved for use and reference somewhere 
 and somehow. Every year something is discovered 
 that was not before known ; but there remains so 
 vast an amount of material yet unknown and unre- 
 corded, that we may be quite sure it will never be 
 exhausted, however long the human race may re- 
 main on the earth, or however highly the faculties 
 of man may be developed. 
 
 Nature offers many of her books for our study ; 
 
 21 
 
22 THE BOOK OF NATURE. 
 
 for every department of knowledge, large or small, 
 may be looked on as a separate volume. Astro- 
 nomy supplies not a few, Chemistry many more, 
 Zoology and Botany each its quota. Of these a 
 number have been read and studied with more or 
 less success. In a few cases we seem to have 
 learnt something of the general plan of Nature ; 
 in others, mere glimpses are made out of local and 
 partial phenomena. Many departments have only 
 lately attracted attention; many, probably, there 
 are which are not yet known to exist. Some, on 
 the other hand, have been in course of development 
 ever since man was an intelligent and observing 
 animal, recording his own experiences for the 
 benefit of future races. 
 
 Of all this vast wealth of knowledge, there is one 
 book that long escaped notice and study, although, 
 since it was first opened in modern times, it has 
 attracted so much attention, and been so exten- 
 sively read, that its name and some of its contents 
 are familiar to all. It is the book which teaches 
 us concerning the structure and composition of the 
 earth we live on, the history of its gradual pro- 
 gress, and of the inhabitants it has had from time to 
 time. It is, in a word, "The Stone Book." The 
 
THE BOOK 01 NATURE. 23 
 
 leaves are the various and successive layers of earth 
 and rock that make up the whole solid mass laid 
 bare occasionally in the cliff and the quarry, but 
 generally concealed beneath the soil, and trodden 
 negligently under foot; its pictures are the pic- 
 turesque remains of its former inhabitants, now 
 long passed away. The Stone Book is the science 
 of Geology. 
 
 When first studied, the facts of Geology the 
 records of this Stone Book, which can be learnec 1 
 only by careful personal observation and an ac- 
 quaintance with the language of Nature were 
 comparatively disregarded, and great stress was laid 
 on inferences and theoretical views of little value, 
 and based on preconceived notions. It is so in all 
 matters. Ignorance is bold, and takes high but 
 useless flights ; true knowledge is modest, and limits 
 her flight to what she knows she can accomplish 
 safely. Ignorance, having few facts, loses sight of 
 all in her endeavors to generalize ; knowledge, with 
 many facts, finds it difficult so to arrange them as to 
 obtain the conclusions they properly warrant. Even 
 at present, those who study Geology are often more 
 apt to generalize than to study detail ; but as the 
 facts multiply the deductions become more sound, 
 
24 THE BOOK OP NATURE, 
 
 though at the same time more difficult. The earth, 
 however, really contains its own history within itself. 
 The leaves of the Stone Book may be carefully 
 conned : what is found in one may be compared 
 with what is indicated in another ; the illustrations, 
 ancient and modern, may be studied; and if, in 
 this as in many other books, the early pages should 
 seem dry and barren of incident, still, as w T e ad- 
 vance, the plot thickens, and the d&nouement, when 
 reached, interests us all directly and personally, as 
 well as tends to clear up early obscurities in the 
 history of Creation. 
 
 By the opening of the Stone Book, I mean the 
 earliest studies of the earth with a view to make 
 out its history, and these studies teach how Nature 
 speaks rather than what she means. First of all, 
 we must learn the language, and even study the 
 dialect, if we may so far carry into detail our lite- 
 rary illustration. And this is so because here, as in 
 various sciences, the class of objects to be studied, 
 and the mode of studying them, must be governed 
 by circumstances. In Geology it is very necessary, 
 in almost all cases, not only to observe, but to infer. 
 In order to infer, careful observations must first be 
 made, and thus there is a double work to be carried 
 
THE BOOK OF NATUEE. 25 
 
 on. As each point is made out, and each fact dis- 
 covered, its meaning and bearing on the whole must 
 be carefully learnt; and all these bearings being 
 brought together, we obtain at last a sound basis 
 on which to rest our conclusions. 
 
 There is but one way in which Geology can be 
 understood, and that is by a thorough familiarity 
 with all that is going on now, both in the animate 
 and inanimate kingdoms of Nature. These repre- 
 sent the language in which the Stone Book is writ- 
 ten. We may open the book at random, and be 
 astonished, but we cannot be interested or instructed 
 without this : for what is any one the wiser, when 
 he or she has merely stared with astonishment at the 
 strange skeletons in the British Museum, or the still 
 more strange stony monsters perpetually threaten- 
 ing the following night's repose of the visitor to the 
 gardens of the Crystal Palace at Sydenham ? He 
 is none the wiser for these visions, if he does not 
 know how and where the bones were found, accord- 
 ing to what principles the skeleton was converted 
 into the semblance of an animal, to what period 
 of the earth's history they belong, and what rela- 
 tion they bear to existing and familiar races. What, 
 again, can be learned at the seaside by the exami- 
 
ZO THE BOOK OF NATUKE. 
 
 nation of a lofty sea-worn cliff, showing varieties of 
 rock utterly unlike similar rock elsewhere, and 
 placed in all kinds of impossible positions, if we 
 have not been taught what is now being done in 
 other parts of the world that may result in a similar 
 cliff? Who can understand the wonderful columns 
 of Fingal's Cave in Staffa, or the Giants' Cause- 
 Way on the coast of Ireland, who has not fami- 
 liarized his eye to similar appearances, where their 
 origin is more manifest, and their history clearly 
 made out ? Experience and knowledge can alone 
 guide us in these matters. 
 
 When, therefore, we speak of the opening of the 
 Stone Book, we allude to all those inquiries and 
 considerations that are preliminary to the study of 
 Geology properly so called. How few persons, 
 comparatively, think of the grand operations that 
 are always going on around us ! These operations 
 are silent, but they are incessant ; and most of us 
 behave as if the things that go on every day with- 
 out disturbance were not really going on at all. 
 The regularity of a change, no matter what its 
 amount may be, is quite sufficient to make us fancy 
 that there is no change at all. The sun shines, the 
 rain falls, the wind blows, the summer and winter 
 
THE BOOK OP NATURE. 27 
 
 succeed each other, and we grow old, fancying all 
 the time that there is no difference, and little aware 
 that all Nature is getting older as well as ourselves, 
 and that nothing of us, and little that is around us, 
 is the same, in a material sense, to-day as it was a 
 few years ago. The times change, and we change 
 with the times ; and because all change together, 
 we act and talk as if there were no change at all. 
 
 Geology is a history of the earth, a history of 
 what it was, and of how it became what it is, a 
 history of the successive events in its progress, of 
 the succession of plants and animals that have oc- 
 cupied it- To learn the history, we must know the 
 causes that have operated ; and thus we are thrown 
 directly upon the study of existing causes of change. 
 For a long time, no one seemed to imagine that a 
 study of what goes on now could help us to an un- 
 derstanding of the earth's early history. But, if 
 not that, what could ? What can we know of forces 
 concerning which we have no experience? How 
 can we judge of the effect of a rush of water, with- 
 out measuring the effect of the nearest approach to 
 a deluge that comes within our experience ? 
 
 To understand any thing of rocks, we must learn 
 how they have been formed ; and to learn this, we 
 
28 THE BOOK OF NATURE. 
 
 must look out for the nearest approach to such form- 
 ations at present. So, also, to understand fossils, 
 which are the remains of former animals and vege- 
 tables, we must study animals and vegetables now 
 living. The present is the key of the past. 
 
 Strictly speaking, the language in which Geology 
 is written is a picture-language, and the pictures 
 are the events going on around us, according to the 
 ordinary course of Nature. The river and the sea, 
 the heat and the frost, the heavy rain and the con- 
 tinual drought, all afford illustrations. In the same 
 way, illustrations are derived from the plants and ani- 
 mals characteristic of our own and other countries. 
 
 As in all cases where Nature is to be studied, it 
 is of singularly small consequence where or how the 
 study begins. Every one in his own neighbor- 
 hood may find enough to amuse, enough to suggest 
 thought, enough to instruct, and enough to puzzle. 
 Who is there who cannot, within a day's excursion, 
 find some cliff, some railway cutting or tunnel, the 
 bed of some stream, some quarry, or some pit, to 
 study ? Even the sinkings made for the foundation 
 of a house or church, or any public work, are often 
 sufficient. Wherever and whenever we can see 
 below the vegetable soil whether reaching gravel, 
 
THE BOOK OF NATURE, 29 
 
 or sand, or stone of any kind there will be some 
 instructive lesson afforded. 
 
 Let us proceed, then, first, to consider what these 
 common appearances mean, and thus become familiar 
 with the hieroglyphic language in which so much 
 of the Stone Book is written. We may then with 
 advantage study the various materials the rocks, 
 as they are called which make up the part of the 
 earth presented for our investigation. 
 
 There are certain appearances and facts so fa- 
 miliar to all that they are seldom thought of, as 
 being themselves only agents in the great work of 
 Nature. It is, perhaps, the perfection of Nature 
 that, in all stages of her progress, she exhibits at 
 the same time, in different places, the birth or first 
 beginning of her great operations, her work fully 
 developed and in perfect condition, and the same 
 work in a state of commencing decay. The purpose 
 for which it was adapted having been accomplished, 
 the completion of each one operation generally 
 serves as the commencement of a still larger pro- 
 gress in another. An illustration from Astronomy 
 will render this more clear. Our earth of itself 
 gives us, in all points, a perfect habitation, perfect 
 
 in its history of the past, perfect in its adaptation 
 3* 
 
30 THE BOOK OF NATURE. 
 
 to the present. All is in order and harmony, and 
 for long ages men believed, naturally enough, that 
 their habitation was the central and only object of 
 God's care. They thought the sun was made to 
 light them alone by day, and the moon to shine at 
 night only for their benefit, that the twinkling 
 light of the countless stars served only to give a 
 faint addition to their night's glory, and that the 
 occasional comet rushed through space merely to 
 warn them of coming danger, or astonish and dis- 
 turb them. They were right in one sense ; for all 
 these are, no doubt, real purposes, except, perhaps, 
 the last. But they thought not of the earth being 
 one only of a group of similar bodies, performing 
 a part in Nature comparatively very small, that 
 myriads of suns existed which they saw not, and 
 perhaps many more myriads of bodies which they 
 never will see or know of, so long as they remain 
 mortal, that the sun served other earths besides 
 this, and that the earth may be as useful to the 
 moon and stars, and even to the sun and comet, as 
 these are to the earth. The whole of the earth's 
 history may be but as a day in the history of the 
 universe, though each fraction of a moment of that 
 day is fraught with important results to every one 
 
THE BOOK OF NATURE. 31 
 
 of us. It is not, indeed, on that account less real 
 and significant, or less perfect. On the contrary, it 
 is more perfect, and perfect in a higher sense, and 
 is far more significant. Every part illustrates the 
 great whole ; every fact in Nature helps to explain 
 every other fact ; and by continually learning more 
 and more about the particular planet which was at 
 their disposal, astronomers have at length succeeded 
 in gaining important and definite knowledge about 
 the distant bodies which they can only approach at 
 second-hand. 
 
 And just so it is with Geology. Every day's his- 
 tory is the key and the clue to the history of ages 
 long since past. By searching out the meaning and 
 object of the small and apparently unimportant 
 changes that are produced by the ordinary action 
 of familiar causes and known modes of operation, 
 the nature of a deposit of mud, the conversion of 
 m d into stone, the change of stone into some other 
 s stance or some other kind of stone, have been 
 successively made out. The history has been ob- 
 tained by comparing and studying familiar things. 
 
 And of all familiar causes, those that are produced 
 by moving water and changes of temperature are 
 incalculably the greatest. Others are occasional, 
 
32 THE BOOK OF NATURE. 
 
 but these never cease ; others may be larger and 
 more active at certain times or in certain places, 
 these go on at all times and in all places. Thus the 
 river-bed and the sea-beach, as illustrations of the 
 influence of sun and rain, wind and frost, afford 
 admirable first lessons in Geology. They teach the 
 alphabet and grammar of the language of our Stone 
 Book. They cannot be too often looked to, or too 
 much thought of. 
 
 It may seem that the only means of obtaining 
 access to the earth's interior must require some 
 operations of digging or quarrying. No doubt the 
 laying bare the framework of Nature, by breaking 
 through the outer shell or crust, is calculated to 
 teach us much useful information ; but we shall see, 
 as we go on, that there are other and sometimes 
 readier methods of opening the book than by the 
 use of the hammer and wedge, the pick and the 
 gad. Many and good lessons may be learnt, and 
 the early pages of Nature's Book may be studied 
 to advantage, even where mines and quarries are 
 not easily accessible. 
 

 J 1 .-x^V- - 
 
THE GREAT STONE BOOK. 
 
 PART I. 
 
Chapter % <4first 
 
 THE RIVER-BED AND THE SEA-BEACH. 
 
 FAR away among the distant hills are the first trace 
 of the great river that rolls along so grandly as it nears 
 the sea, carrying on its broad bosom the ships that come 
 and go and help to communicate with all parts of the 
 world. Very clear and bright is the water that first 
 bubbles out of the earth and runs along the narrow rocky 
 bed. You might step across it easily there, and walk 
 up through the stream without wetting your ankles. A 
 little further on, indeed, there begin to be holes, in 
 which speckled trout love to take shelter; and further 
 on still is the first mill, near where the country opens 
 out at the foot of the hills, and now villages are seen, and 
 corn-fields and orchards. Afterwards other streams join 
 the growing river : each individually is small, but each 
 helps to increase the supply of water ; and as the river 
 flows onwards it becomes gradually wider and deeper, 
 and moves with a more even and regular pace, utilized all 
 the way, either to drive wheels or to irrigate the soil, or 
 else made to branch off into some canal, on which the 
 barges are constantly travelling, laden with the produce 
 of the interior or carrying into the country various ar- 
 ticle? brought from the sea-coast. 
 
 35 
 
00 LANGUAGE OF THE BOOK. 
 
 The history of a river is often a simple statement of 
 this kind, commencing as a spring of living water, gush- 
 ing from a hill-side, and finding its way in some natural 
 channel over the surface. By small degrees and success- 
 ive additions it becomes a considerable body of water, 
 flowing along a well-defined channel and draining a large 
 tract of country. Occasionally, it meets with obstacles, 
 and is swollen into a lake, or it leaps over a cataract 
 before it leaves the hills; and sometimes, after having 
 long occupied a sufficient channel, it enters a rocky or 
 mountain gorge, where it hurries along over rapids, or 
 dashes with resistless force down a precipice into the 
 valley below. 
 
 At a certain point in its course, our river, as it ap- 
 proaches the sea, meets a body of salt water forced up by 
 the tide, and there the salt water, alternately forced for- 
 ward and carried backwards beneath the fresh, produces 
 a corresponding tide of fresh water, interfering with the 
 otherwise uniform course of the river's current. When 
 the fresh water enters the sea, it floats for some time 
 before it becomes so far mixed with the salt as to form a 
 common part of the great ocean. 
 
 Throughout its course, whether amounting only to a 
 few miles or continuing for hundreds of miles, the water 
 is constantly running. Whence comes this large supply, 
 and how is it that the river never ceases its flow to the 
 sea, and in many countries never seems to alter much in 
 the depth or width of its channel? The small spring 
 that forms the source would not, if multiplied a thou- 
 sand times, fill this wide and deep channel. It is in fact ; 
 by an almost infinite multitude of small streamlets enter- 
 
THE RIVER-BED AND THE SEA-BEACH. 37 
 
 ing, after every shower of rain, from all the gutters and 
 puddles and drains, not only into the river itself, but 
 into all the smaller rivulets that feed it, that the great 
 body of water is obtained that finds its way to the sea. 
 Every shower thus helps to feed the river, and the rain 
 that falls is sure to find some ready means of getting 
 back to the great reservoir from which it originally came. 
 
 If we look at the river after wet weather, we find it 
 muddy : the water is loaded with particles of the soil, 
 and these are carried along as far as we can see. We 
 know that the mountain-rill and the trout-stream are 
 clear and bright, for we can see every pebble at the 
 bottom ; and we might be at a loss to know how the mud 
 came into the water, if it were not for the explanation 
 just given. The soil is washed into the river, and part 
 of it is carried by the river a long way. 
 
 Now let us look at the bottom or bed of the river. 
 Near its source it consists of large, broken, rough stones 
 often huge masses of granite, or limestone, or sand- 
 stone; and if we watch for a few seasons, we shall see 
 that these do not remain in the same place. They are 
 carried down, perhaps, only a few yards in a year, but 
 still they move. We do not suppose that the force of 
 the stream is strong enough to carry them along, for we 
 can easily keep back the water by the hand, but could 
 not with any effort move the larger stones. The stream, 
 however, works insidiously and undermines as it goes 
 along; for the water is always moving a multitude of 
 small stones on which the larger blocks rest, and from 
 time to time, their floor being taken away, they tumble 
 over the direction they take in falling being always 
 
 4 
 
38 LANGUAGE OF THE BOOK. 
 
 governed by that in which the water is going. Being con- 
 stantly rolled over and over, and knocked against by 
 other stones, they are often broken, and as they get down 
 the stream they become smaller and smaller, being more 
 easily and frequently rolled over and broken, till at last 
 they are reduced to pebbles, whose edges are rounded 
 and almost polished by being rubbed constantly one 
 against another. While these pebbles are being made, 
 the smaller particles are converted into still smaller stones 
 and sand. This is the way in which the bed of the 
 brook and mountain stream is produced. It is a mixture 
 of sand and stones of all sizes and shapes, and the whole 
 of it has been obtained by slow degrees from rocks, 
 which were at first hard, solid masses, just like those we 
 now find it so troublesome to climb over to get at the top 
 of the hill. 
 
 The bed of the river lower down is made up nearly in 
 the same way, only instead of stones the mud is brought 
 in from the clay lands on the banks. More clay than 
 sand is carried along by the water, because the particles 
 of clay are smaller, and do not sink so fast as the large 
 pieces of stone. It is not that the clay is really lighter 
 than the stone, because if you take a hard lump of clay 
 and throw it into a basin it will sink to the bottom as 
 fast as any stone, but if you mix it well up the water will 
 look dirty. After a time all the little particles of mud 
 will, however, sink, and the water will clear again. 
 
 The water carries along the mud and stones with it, 
 and the faster it flows the further of course they travel. 
 At last, if the river enters a lake and ceases to run so 
 fast, they sink down, and the river runs clear from the 
 
THE RIVER-BED AND THE SEA-BEACH. 39 
 
 other end ; but if the river flows on to the sea the mud 
 goes with the water, dropping as it goes, but always sup- 
 plied again at every mile from the banks on each side, 
 till at last the fresh water approaches the great body of 
 salt water in the sea. As the sea only rises and falls 
 with the tide, except where the tide runs up the river, 
 there are no longer the means of carrying on the mud, 
 and it sinks to the bottom. 
 
 Do you see now what all this comes to ? The river 
 receives muddy water, sand, and stones, and carries all 
 these along a little way; but as it is always receiving 
 some, and always letting some sink, and always carrying 
 some along to the sea, where it all stops, the bed of the 
 river must be constantly getting higher and higher, and 
 at the mouth of the river there must be a great heap of 
 mud, which the river has been bringing down ever since 
 it was a river. 
 
 SECTION THROUGH AN ALLUVIAL VALLEY. 
 
 a. The hard rock eaten through to form the valley. 
 6. The alluvial mud deposited by the stream, 
 c. The present bed of the river. 
 
 If you look at the banks of a river you will generally 
 find, as marked in the cut annexed, that they are made 
 of nearly the same kind of mud as the bottom or bed : 
 at least, this is the case near the mouth of the river, and 
 where it runs through open country. In these cases, 
 
40 LANGUAGE OP THE BOOK. 
 
 what are now the banks have been at one time the bottom ; 
 and though there seems no change, the channel of the 
 river, or the hollow space along which the water runs, 
 is constantly shifting perhaps only a few inches in 
 a year, but still enough to keep the course clear. The 
 current of the water is always strong enough to eat 
 away part of the banks or the bed to make room for 
 itself. 
 
 The surface of a country is everywhere connected with 
 some one or other of the rivers running through the 
 country, and the whole is constantly being pared away. 
 It is true that the process is slow, but it is incessant ; 
 and the mud thus moved is heaped up at the mouths of 
 the rivers, tending to extend the land horizontally, giving 
 a larger surface and reducing the elevations. 
 
 This is a great lesson in Geology. Over the whole 
 world the hills and mountains are being gradually moved 
 away bodily, and lowered by degrees, because of the rain 
 which falls on them and runs off to form the rivers ; and 
 the stones and mud carried away help to fill up the sea. 
 This is the inevitable effect of rain, and it is not a small 
 effect, for the whole of Holland is entirely formed by 
 the mud thus brought down by the river Rhine; the 
 greater part of Lower Egypt, the most ancient agricul- 
 tural country in the world, was deposited in the same 
 way by the Nile ; an enormous country in India is the 
 result of deposits left behind by the Ganges; and, in 
 America, the city of New Orleans is built on mud which 
 the Mississippi has brought down from the interior of 
 the continent it drains. Every day throughout the year 
 does this great river throw into the Gulf of Mexico 
 
THE RIVER-BED AND THE SEA-BEACH. 41 
 
 sufficient mud to make a conical hill half a mile round 
 at the bottom and sixty feet high. 
 
 Let the reader endeavor to imagine what this would 
 have been if the mud had really been collected and 
 piled in heaps half a mile apart. In the course of a 
 thousand years these hills would have occupied a space 
 as large as the whole of the British Islands, France, 
 Belgium, and Holland. And yet the Mississippi is but 
 one of the great rivers of the earth ; and all the others, 
 whether great or small, are always doing similar work, 
 some of them, perhaps, at a more rapid rate. 
 
 The river-bed, then, is not to be despised. It repre- 
 sents the result of running streams in removing solid 
 matter all over the earth, and a little consideration shows 
 that a great deal of such work is done. 
 
 But it must not be supposed that, having looked at the 
 beds and banks of rivers, we have seen all the effect of 
 moving water. Almost everywhere there is a wide space 
 of comparatively flat land near the river, particularly 
 during the latter part of its course, and all this, too, has 
 been produced by the same cause, though completed long 
 ago. Even far up steep mountains, and away from all 
 rivers, there are often flat patches of cultivated land, and 
 occasionally bogs and marshes; while many rocks, ex- 
 posed to the action of running water, and formerly bare, 
 are now thickly covered with vegetable soil. Almost 
 everywhere we may see, by a little careful examination, 
 some of the changes that have been produced on the land 
 by this powerful agent, many of them commenced and 
 completed within even that short time during which we 
 have any good maps, or an account we can depend upon. 
 
 4* 
 
42 LANGUAGE OP THE BOOK. 
 
 The sea-beach is covered with pebbles and coarse sand, 
 and sometimes with very fine sand and mud, wherever 
 the bare, naked rocks do not present a strong wall against 
 the inroads of the waves. But the sea-beach is not quite 
 like the river-bed : the pebbles are rounder, more uni- 
 form, and more abundant, the broken rocks more jagged, 
 the sands more shifting, the mud is not of the same 
 kind; and altogether there is a sufficient difference to 
 enable any geologist to say at once, if taken to a natural 
 heap of gravel or bed of mud, to which cause the heap- 
 ing together was due. Sea-beaches are found sometimes 
 inland, so that the difference requires to be learned by 
 the young geologist. 
 
 Most persons have listened, at Brighton or elsewhere, 
 to the peculiar and incessant roar of the sea as it breaks 
 upon a pebble shore. Along many miles of beach the 
 restless waves are always either advancing or receding, 
 according as the tide is rising or falling, and every wave 
 carries backwards and forwards a certain breadth of 
 pebbles, which are then made to roll over each other 
 with some force. Now, if stones are rubbed together the 
 corners are knocked off, and they become at last smooth 
 and round, and it is in this way that all pebbles are 
 produced. The particles broken from them form sand ; 
 and as there is thus a constant tendency to grind the 
 .sea-pebbles into sand, there can be no doubt that in a 
 short time they would all be worn away, if there were 
 not an ample supply constantly provided. It is a curious 
 question where the new pebbles come from, and one not 
 always easily answered. Generally, however, we can 
 trace them readily enough to the rocks not far off. .Just 
 
THE RIVER-BED AND THE SEA-BEACH. 43 
 
 as the blocks in the river-bed get broken up and carried 
 away, so those that fall from the cliffs into the sea are 
 turned, after a time, into smaller stones and sand. Where 
 the whole rock is hard the quantity of sand is small, but 
 where the rock is soft, even if it contains hard lumps, 
 there will be a great deal of sand or mud, or both, to 
 mix with the pebbles. But the mud is easily removed, 
 and is generally carried into sheltered nooks, where the 
 tide has little force, and where the water is still. Wher- 
 ever water is left undisturbed the mud will sink and 
 be found at the bottom, leaving the water itself clear and 
 transparent. 
 
 Very large and deep accumulations of gravel and sand 
 exist near the sea, and wells are often dug in such gravel, 
 in places where one would suppose the sea had never 
 been. But a heap of well-rounded beach-pebbles must 
 have been brought to their shape and rolled about in 
 water, so that we are obliged to suppose either that the 
 sea has left that part of the shore, or else that the whole 
 body of the land thereabouts has been upheaved from 
 below; unless, indeed (which is perhaps sometimes the 
 case), the pebbles and sand have been gradually thrown 
 up until they formed a kind of natural wall which the 
 waves do not break through except on very extraordinary 
 occasions. The water in the ocean is just like that in a 
 trough or cistern, the surface of which cannot for any 
 time be kept aslant. It is one of the properties of all 
 liquids to come to a level wherever they are placed, and 
 so the sea must ever retain its level, one part not remain- 
 ing permanently lower on any coast, unless, indeed, the 
 whole body of water in the ocean were to diminish or 
 
44 LANGUAGE OF THE BOOK. 
 
 become lowered by the deepening of its bed ; and of this 
 we should have independent proof. 
 
 Almost everywhere, then, in the neighborhood of all 
 the rivers and little streams, by the sea-side, and even in 
 the open country of some parts of the world, there is a 
 constant movement and shifting of the earth's surface. 
 There is a proverb which says, " continual dropping will 
 wear away stone," and it is perfectly true in every sense ; 
 for where water is constantly dropping or running or 
 beating, by the action of the waves, stone, however hard, 
 is gradually but surely worn away, while sands and mud 
 are eaten into very fast. But water is wonderfully helped 
 in all these cases by the rubbing together of the stones 
 themselves, which at first it may only be just able to 
 move, but which are soon rolled over and over; and since 
 the water never gets tired of doing its work, but takes 
 advantage of every little chance that comes in its way, 
 we find that, however slow the process at first, an im- 
 pression is soon made, and in time the hardest granite is 
 turned into the finest mud, and nothing can resist so 
 indefatigable an instrument. It must be remembered, 
 too, that the rain of to-day, falling on the ground clear 
 and running off by a dirty puddle, becomes the cloud of 
 to-morrow by the process of evaporation, but leaves the 
 mud behind. Passing through the air, it may fall again 
 in rain at some other place ; so that if it has not a long 
 course, and does not on each occasion perform a large 
 task, it at any rate is soon ready to recommence its work. 
 If it runs long over the earth it is always helping to 
 move solid matter, and when it retires into the bosom of 
 the ocean it is still never at rest. There is, indeed, no 
 
THE RIVER-BED AND THE SEA-BEACH. 45 
 
 such a thing as rest for water, even for a moment, for 
 water is always in circulation here and there and every- 
 where, in the sea, in the river, in the air, on the earth, 
 and even within the earth. Not only is it never quiet, 
 but it is always helping to move and disturb and destroy 
 all other created matter. 
 
 This account of what water does in the river and on 
 the sea-beach clears up wonderfully some of the great 
 mysteries of Geology. In Geology we have to examine 
 large results, and we cannot judge of them at all with- 
 out knowing something of the operations now going on 
 upon the earth, since these afford the only means of 
 comparison open to us. In all these water is an import- 
 ant agent. It acts very widely and very powerfully, 
 without ceasing, and often without much noise. Its 
 effects are easily overlooked, and not very easily done 
 justice to, so that there is little fear of its real import- 
 ance being estimated too highly. 
 
 If we would learn the ordinary language of Nature, 
 we must study the familiar expression of her ways as 
 events pass on from hour to hour, from day to day, and 
 from year to year, with a true regularity, and even 
 monotony, in the midst of the greatest apparent irregu- 
 larity. To do this, it is absolutely necessary to consider 
 the effect of water as it circulates through the earth, as 
 it passes from the sea to the sky, and as it returns in 
 refreshing showers from the sky to the earth, and so 
 back again to the ocean. It is this circulation more than 
 any thing that serves as the means of communication 
 the connecting link between the power and the con- 
 veyer of power. It is to the ordinary force of running 
 
46 LANGUAGE OF THE BOOK. 
 
 water that we must refer many changes apparently far 
 too great to be thus brought about. It is to this that we 
 must ultimately refer, even when many other causes act, 
 each of which apparently is much more powerful. 
 
 The river-bed and the sea-beach, inasmuch as they 
 illustrate the ordinary action of running water, are be- 
 yond a doubt the most instructive and the most interest- 
 ing of all the studies preliminary to Geology ; but, after 
 all, they represent only one of several ways in which 
 water acts upon .the earth. They do not include the 
 results of changes of temperature on substances contain- 
 ing water, nor do they refer to the action of ice. Let 
 us pursue the subject, then, a little further in another 
 chapter. 
 
THE SUN, THE WIND, THE RAIN, AND THE FROST. 
 
 THE brook and the wave break up the large stones that 
 fall into the bed of the one from the mountain-side, or 
 come under the action of the other on or near the shore. 
 But how do the large stones first become loosened from 
 the rock, and what are the causes of so much material 
 being supplied to make pebbles, sand, and mud ? If we 
 watch the mountain-side or the sea-cliff, we may obtain 
 an answer to these questions. 
 
 After a long dry season the earth is parched and 
 cracked at the surface, clays gaping with wide fissures, 
 and some other rocks, such as sandstones, showing open 
 splits of considerable depth. In warm countries these 
 are several feet wide and some yards deep; but even in 
 England, though rarely so wide, being measured by 
 inches instead of feet, they penetrate some distance. 
 This is evidently the effect of the sun's heat in drying 
 and so contracting the surface of rocks. Some things 
 swell with heat and become softened, but earth and rocks 
 losing their moisture shrink and get harder, as any one 
 may satisfy himself by a little observation. 
 
 But after long drought comes a shower of rain : the 
 
 rain pours down at once into the cracks, and penetrates 
 
 47 
 
48 LANGUAGE OF THE BOOK. 
 
 far down into the interior of the rock. The part first 
 moistened cools and swells, and acts as a kind of wedge, 
 splitting the whole into pieces if the rock is at all brittle. 
 Down come large fragments tumbling into the bed of the 
 stream; other detached blocks rest for a time on the 
 hill-side, while others come within the influence of the 
 sea, falling at the foot of the cliff, and these before long 
 are all broken up into smaller stones and converted into 
 pebbles or mud. 
 
 But it is not only in summer that the rocks fall to pieces 
 and feed the rivers and the sea. Long-continued rain at 
 any time penetrates through the crevices of rocks and soft- 
 ens the muddy and clayey parts, so that the harder upper 
 beds slip down over the lower ones and fall into the 
 valley below, where they are allowed to disintegrate slowly 
 in the air, or are rapidly broken up by the water. The 
 same result follows : the work begun by the sun or 
 the rain is finished by the river or the sea, and the earth 
 'is pared of yet more of its surface. 
 
 When the winter comes the effect is similar, but still 
 greater. Water swells a little when it is about to freeze, 
 as most people know who have left a narrow-necked jug 
 full of water exposed in winter weather. Almost every 
 night, therefore, for some months of the year in temper- 
 ate climates, there is a continual swelling out and shrink- 
 ing in of the water in rocks, as far as the weather can 
 penetrate. At last, towards spring, the heavy rains come 
 once more and wash down into the lower depths the 
 whole top of the rock, which is then in a state to fall to 
 pieces on the slightest disturbance. 
 
 It might be supposed .that, with all this movement 
 
SUN, WIND, RAIN, AND FROST. 49 
 
 constantly going on, the whole face of a country would 
 be changed every year, so that it would be difficult to 
 know where the landmarks had been placed. It must be 
 remembered, however, that in cultivated countries 
 where the land is drained, where roads and hedges inter- 
 sect the fields, and where men do all they can to prevent 
 injury to the surface the effect is comparatively small. 
 Even in places where men do not grow crops, a natural 
 covering of wood or grass is a very great protection to 
 the surface, the roots binding the soil together, and 
 checking that wearing away that would otherwise be pro- 
 duced by the rain. It is only where the ground is 
 uncultivated that the full effect is seen ; and even then 
 the first change, which turns the hard rock into a rotten 
 earthy soil, will in many cases check further destruction, 
 if the soil is not at once carried off by the rain. 
 
 At the same time it will be evident that near the sea, 
 or in hills and mountains where rivers take their rise, and 
 where there are steep cliffs, there will generally be a 
 large quantity of broken rock ready to be ground up into 
 pebbles every year ; while in other places, exposed to the 
 same weather, there is hardly any amount of alteration 
 or destruction to be noticed. 
 
 Many countries are so placed as to have exceedingly 
 cold weather during a large part of the year. This is 
 the case near the poles of the earth, where there are but 
 two seasons, a short summer, and the long tedious winter; 
 and it is the case also near the tops of several of the 
 great mountain-chains in different parts of the world. 
 Owing to the absence of any quantity of solid earth to 
 get warmed by the sun's rays, these high peaks and 
 
 6 
 
50 LANGUAGE OF THE BOOK. 
 
 ridges are always excessively cold ; and when it would 
 rain below, snow there falls at almost all seasons. 
 
 Ice, or water in the solid state, which, in England, is 
 only occasionally formed during cold winters is always 
 present in these places, and takes the place of water. Let 
 us see what difference this makes in the action of the water* 
 
 Those great mountains the Alps, and particularly the 
 parts of the chain situated in Switzerland, are remarkable 
 for being always covered with snow. People who have 
 not actually travelled can hardly form an idea of the ex- 
 ceeding beauty of a distant chain of lofty snow-capped 
 elevations, shooting up into the sky with every variety of 
 jagged and rounded summit. As you get nearer you see 
 large dark patches, where either naked rock juts out, or 
 where are green slopes covered in summer with cattle ; 
 and then, as you come close to the mountains and go 
 amongst them, you find besides the top, which is always 
 white with snow, there are numerous patches of snow, 
 covering thick heaps of ice, reaching down quite into the 
 valleys. In winter these cover the whole flank of the 
 mountain, and even occupy parts of the lower valley; 
 but in summer the surface-snow melts, and we can easily 
 examine and walk over vast fields of ice. 
 
 I advise any of my readers who have the opportunity, 
 to look carefully at one of these patches, for they show, 
 more clearly than any description, what ice and frost on 
 mountain-sides are able to perform ; but those who have 
 not such opportunity may still feel interested by an ac- 
 count of what others have seen. The path of the ice in 
 the larger ice-fields is marked very distinctly on the 
 mountain-side, and there are often many instances, of 
 
SUN, WIND, RAIN, AND FROST. 51 
 
 exactly the same kind, easily seen and examined within 
 a narrow breadth of country. The mountain-side is, 
 in such cases, smoothed towards the valley, and covered 
 with a continued string of stones of all sizes, the 
 breadth gradually increasing, and terminating at the 
 bottom in a wide and large heap. Just at this point 
 there is, generally, running water, and the heap gradually 
 diminishes during summer. Where the mountain is high 
 and the sides steep, but not too steep to allow the ice 
 to rest on it without falling, there is sometimes no inter- 
 val at all between these broad strips of broken stone. 
 Where the mountain is steeper, the ice and stones are 
 seen at intervals only, and between them are waterfalls, 
 numerous white threads of water leaping down hundreds 
 of feet ; while very often the bottom of the fall, and the 
 valley beyond and below, are so completely blocked up 
 by the broken rocks that it is difficult to walk along. 
 Millions of tons of stone and rock are seen, all of which 
 have been recently moved, and the ice and water which 
 helped to move this vast quantity are still visible. 
 
 The same thing goes on, the constant breaking away 
 of the mountain, continuing during winter by help of 
 the frost in the upper part, where the ice never alto- 
 gether disappears. The stones and mud are thoroughly 
 mixed with the ice and form a part of it ; they gradually 
 come to the top, because the surface of " the ice is always 
 being evaporated by the air, and fresh material is sup- 
 plied by the frozen snows above. 
 
 Such masses of ice, and some of them are many miles 
 in length and of great breadth, are called glaciers. 
 They look as if they were quite still, and the ice of 
 
52 LANGUAGE OF THE BOOK. 
 
 which they consist is often concealed by newly-fallen 
 snow all through the summer ; but they are always in 
 motion, the ice creeping slowly down the valleys with 
 a peculiar motion, and melting at the lower end. From 
 the foot or lower extremity of glaciers proceed the first 
 germs of the principal rivers in Europe, and the ice is 
 advancing incessantly, bearing down along with it, in its 
 progress, the stones and mud torn away from the moun- 
 tain top and sides. These, of course, ultimately enter the 
 valley and are broken up by the running water. 
 
 A glacier may be formed in any part of the world, 
 provided the mountains are sufficiently lofty and the 
 prevailing winds carry moisture enough to insure fre- 
 quent falls of snow. But in those high northern and 
 southern lands where cold sufficient to freeze water is 
 hardly ever absent, as on the shores of the Arctic and 
 Antarctic seas, similar but much larger masses of ice, 
 formed in the same way, taking their origin from the 
 steep cliffs, and coming from the interior and higher 
 land, push forward, occupying creeks and inlets, until 
 at last they break off and float away. 
 
 In some parts of the world the wind combines with 
 the rain and cold, or even acts independently of it, in 
 removing solid matter from one place to another. On 
 the coast of Flanders, between Dunkirk and Ostend, is 
 a tract of country where almost every wind that blows 
 drifts sand to such an extent as to require careful man- 
 agement lest property should be seriously injured. By 
 making nature oppose herself, by bringing vital energy 
 to bear against mere mechanical force, and fixing the 
 loose sands by causing roots of particular kinds of grass 
 
SUN, WIND, RAIN, AND FROST. 53 
 
 to penetrate them in every direction, the sand-drift is 
 either stopped or seriously checked. 
 
 But in Egypt, and over the whole of that wide and 
 large and little-watered tract in North Africa, known 
 as the Great Desert, the moving columns of sand are 
 not checked, and they have already concealed and buried 
 enormous tracts of fertile land, at one time richly culti- 
 vated. There no plants seem likely to grow which could 
 fix the sand, nor are efforts made by human intelligence 
 to combat the natural powers at work. A continual 
 advance of the sand towards the east, due to the preva- 
 lence of westerly winds, is a fact no less influential, and 
 produces results no less marked, in Northeastern Africa, 
 than the alternate frost and thaw of the northern coun- 
 tries of Europe, or the rain that washes down its mil- 
 lions of tons into the great rivers of Central Asia and 
 America. 
 
 Even the lightning-flash, restoring by a suddan and 
 energetic communication the electric equilibrium be- 
 tween the air and the earth, is capable of producing 
 effects which tend to change and disturb the soil and 
 break up solid rock. Instances are on record of con- 
 siderable disruption of hard sandstones effected in this 
 way; and as rocks once broken or split, however hard 
 they may be, are soon worn down and lost sight of, 
 even this source of change and destruction must not be 
 disregarded. 
 
 Sun, wind, and storm, rain, snow, and hail, frost 
 and thaw, summer and winter, are thus found to be 
 all of them favorable to the process, eternally going on, 
 of smoothing and paring away the rough surface inequali- 
 
 5* 
 
54 . LANGUAGE OF THE BOOK. 
 
 ties, and scooping out new channels and furrows on the 
 earth's wide surface. 
 
 There is no day and no hour when such forces are not 
 at work; and we have every reason to conclude that this 
 has always been so, and that at all former periods, as 
 much as at the present time, disturbance and change and 
 mechanical displacement are among the inevitable events 
 of Nature. So far as we can tell, they are inevitable 
 results of the course of Nature as it has been settled for 
 the earth ; for nothing else could arise from the admix- 
 ture of the three conditions of matter, solid, liquid, and 
 gaseous. So long as this has continued, so long must 
 there have been the same equilibrium produced by the 
 same means, a means admirably adapted, no doubt, to 
 carry out the intention of the Great Creator, but very 
 difficult for us fully to comprehend in the present limited 
 state of our knowledge. Without these conditions, how- 
 ever, all would be still with the stillness of death. Life 
 consists in this incessant play. Life, perhaps, means 
 some struggle of this kind, in which the elements are 
 constantly entering into new combinations, constantly 
 releasing themselves from those in which they have for 
 a time been imprisoned. Certainly life, in the sense in 
 which we inhabitants of the earth understand it, has very 
 distinct reference to the conditions of matter on the earth. 
 Were the latter to be changed, were the mean tempera- 
 ture of the air to admit the water generally to be fixed 
 in ice or converted into steam, how enormous would the 
 difference be! how completely would almost the whole 
 group of animals and plants pass away ! 
 
 Thus, then, destruction and renovation, effected by 
 
SUN, WIND, RAIN, AND FROST. 55 
 
 means of air and water, is one of the laws of Nature : it 
 is the law which leads us to all others ; it is the thing to 
 be understood if any thing of Nature's ways is to be 
 learnt. We shall see hereafter how clearly this action of 
 water is marked in all, or nearly all, the rocks that have 
 been formed, and how, if it has not really produced them, 
 it has affected their production. 
 
 We shall also see, if it is n.ot already plain, that heat 
 and cold must be constantly alternating; that there must 
 be a means of producing incessant change of temperature 
 if these vast changes and reconstructions of the earth are 
 to proceed. We do not really know, and probably never 
 can know, what conditions of temperature are most 
 favorable to the rapid destruction and reconstruction of 
 rocks. Geologists assume, without knowing much about 
 it, that a higher temperature than we have now, even 
 in the tropics, has formerly existed all over the earth, 
 and would do more in a given time to effect and alter 
 deposits than is now done in that time. On the other 
 hand, we know that many of our greatest recent changes 
 have been brought about in a very cold climate. At 
 any rate, climates have altered, and perhaps the alter- 
 ation itself has been more important than the nature 
 of it. 
 
 Not one of the elements and causes of change to which 
 we have alluded in this chapter and the last is without 
 very great influence and meaning. The sun, as the 
 source of heat and the direct cause of other changes 
 independent of heat and of a chemical nature, is one of 
 the chief. The wind or periodic and occasional motion 
 of the air acts in many ways, directly and indirectly, but 
 
56 LANGUAGE OF THE BOOK. 
 
 always with much effect. It distributes heat, moisture, 
 and cloud. It induces changes in the electrical state of 
 the air, and thus affects the supply of rain. When inter- 
 rupted, it produces great mechanical pressure. 
 
 The rain is too manifest a source of movement to re- 
 quire more than mention. The frost splits up the ground 
 and prepares it for farther change. The following dia- 
 gram offers a curious illustration of this, in a part of the 
 world where the changes of weather are very great: 
 
 EFFECTS OF ICE ON THE BANKS OF THE DWINA. 
 
 a. Limestone rock. b. Sand hillocks. 
 
 c. The limestone broken up by the winter's frost. 
 
 d. The summer level of the stream. e. The winter level. 
 f. The road on the banks of the river. 
 
 Besides all this, every stream of water running over 
 the surface collects the small results and distributes them 
 in order, carrying some far, leaving others near; while 
 the great ocean, when reached, finally arranges and dis- 
 tributes what is brought down by the river, as well as 
 what it removes by its own waves. 
 
 If we could add together the whole annual amount 
 carried along by rivers and left behind before reaching 
 the sea, including the solid rock broken away and con- 
 verted into boulders, pebbles, sand, and mud, of cliffs 
 ground into sand and mud by the sea, of sands drifted 
 by the wind, of mountain-peaks, jagged rocks, and cliffs 
 thrown down and conveyed away by ice ; and if we could 
 
SUN, WIND, RAIN, AND FROST. 57 
 
 multiply this large total by the number of years during 
 which such work has been going on before our eyes, we 
 should understand, better than we can now, the vast im- 
 portance of considerations of this kind in explaining the 
 great changes that, in the course of that time, have been 
 produced on the earth. Without a careful study of 
 Nature in these matters, in different countries, at various 
 seasons, and under different influences, no one is justified 
 in forming an opinion as to the value of geological evi- 
 dence, and, indeed, no one can fully understand the 
 nature of Geology, or the possible extent of changes on 
 the earth's surface in ancient times. 
 
 Having now considered these fundamental matters, and 
 learnt something of the mode in which Nature acts at 
 present to produce new things out of old, it will be con- 
 venient to pass on at once to consider the materials with 
 which geologists have to deal, the so-called "rocks" 
 not always rocky and hard, but, in a word, the materials, 
 whatever they are, of which the earth's external shell is 
 composed. These, of course, vary in different places. 
 They are all, however, reducible to a small number of 
 principal varieties; for they have either been left behind 
 by water, or built up by animals, or accumulated by plants, 
 or they have undergone some chemical change within the 
 earth, or finally they are, or have been for a long while, 
 within the earth in a melted state. The former are of 
 three kinds : they are clays, limestones, and sandstones. 
 The latter are either lavas or granites, or what are called 
 schists. 
 
 Let us begin with one of the most common and familiar 
 of all, the clays that, in one shape or other, are uni- 
 
58 LANGUAGE OF THE BOOK. 
 
 versally spread over the earth. Of all rocks, clays are the 
 most manifestly derived from water, and they are among 
 the least altered from their original condition as mud. 
 
 They have, however, undergone many and great changes, 
 and are adapted to illustrate our history of the Stones of 
 the Great Book. 
 
THE GREAT STONE BOOK. 
 
 PART II. 
 
CLAY AND ITS VARIETIES. 
 
 BY clay we understand, not merely the substance com- 
 monly so called, whether in the fields helping to make 
 vegetable soil, or in the pits worked for brick-making, or 
 exported to make porcelain, or for other special purposes, 
 but also various minerals and rocks derived from it. 
 In this general sense it is a complicated rock of great 
 importance and of great interest. 
 
 And, first of all, let us go back to its origin, and con- 
 nect it, as far as possible, with the element from which it 
 is derived. It is not desirable to do this in all cases in 
 Geology; for many elementary substances, interesting 
 enough to the chemist, are so rare and have so few pro- 
 perties of general interest as not to be worth considering 
 by the geologist. Not so with clay ; for the element from 
 which it is derived is already manufactured in sufficient 
 quantity to show that it may hereafter possess import- 
 ance in the arts, while it is quite remarkable enough to 
 have attracted much attention, and to have been the 
 object of important experiments. 
 
 There is a beautiful metal recently brought into use 
 for making bracelets, brooches, and some other personal 
 ornaments ; and this metal, while almost of the color of 
 silver, is only about one-fourth its weight, being in fact 
 
 6 61 
 
62 THE STONES OF THE BOOK. 
 
 no heavier than so much glass. It is called ALUMINIUM; 
 and, although new in one sense, its existence as a chemi- 
 cal curiosity has long been known. This singular sub- 
 stance, called a metal, but in many respects very little 
 like other metals, mixes readily with oxygen gas, and 
 when in the mixed state occurs naturally in several dif- 
 ferent forms. It is then known as ALUMINA. Crystal- 
 lized, it becomes a precious ruby or sapphire ; half crystal- 
 lized, but equally pure, it is known as emery, a sub- 
 stance sufficientlyrare, but not costly, and found some- 
 times as a stone, sometimes as a coarse powder. In either 
 form alumina exists ready made in rocks ; whereas the 
 metal aluminium is only to be obtained by an extremely 
 expensive and troublesome chemical treatment of some 
 natural ore. 
 
 When, however, the comparatively rare mineral, alumina, 
 has combined in nature with another very common sub- 
 stance, silica or flint, a third product results, and this is 
 infinitely common and abundant everywhere. This pro- 
 duct, mixed with a little water, is, in fact, CLAY. 
 
 Clay, then, is derived from alumina, as that is derived 
 from aluminium. It is called by chemists a silicate of 
 alumina , to denote its composition, and the form in which 
 one of the metals exists, under ordinary conditions, at 
 the earth's surface. 
 
 Silicate of alumina, however, in a perfectly pure state, 
 without water, is hardly found in nature. It occurs in 
 a complicated and ever-changing series of combinations, 
 and when mixed up with a vast variety of other sub- 
 stances as well as water, it is of universal occurrence. It 
 forms a few rare minerals ; but we will not here trouble 
 
CLAY AND ITS VARIETIES. 63 
 
 ourselves with the rarities, since the commonest clays 
 are exceedingly useful ; and will supply us with ample 
 material for illustration. 
 
 The foundation of all natural clays is, we have seen, 
 silicate of alumina combined with water; and the propor- 
 tion of water varies, according to circumstances, from 
 ten to twenty-five per cent. All clays contain, also, a 
 mixture of sand and some impurities, these latter, indeed, 
 often giving a distinctive character to the varieties. The 
 common materials met with in clays as impurities are 
 the oxides of iron and manganese, carbon, soda, and 
 potash, and more or less lime and magnesia. Other sub- 
 stances may be present accidentally, but these are all very 
 common ; and the quantity of them, and sometimes also 
 the way in which the foreign ingredients are mixed up 
 with the pure mineral, affect the value of the result for 
 those purposes for which the clay is to be used. 
 
 One of the properties of clay, which renders it so much 
 more useful than many substances apparently more valu- 
 able, and so indispensable to man in almost every state 
 of civilized existence, is its plastic nature, or, in other 
 words, the property it has of working up into a paste with 
 water, and when once moulded in this state, and exposed 
 to high heat, parting with the water without losing the 
 form given to it. It is in this way that clay becomes 
 brick. When it has thus been exposed to great heat, 
 and the water got rid of by burning, clay cannot again 
 be made soft and plastic by merely mixing it with water. 
 
 Many stones, if ground very fine and mixed with water, 
 can also be moulded and brought into shape ; but in these 
 cases a complete and permanent hardening would not be 
 
64 THE STONES OF THE BOOK. 
 
 secured by any heat that the mixture could endure with- 
 out melting. Some of the clays (though reckoned as 
 among the most refractory and troublesome of all rocks) 
 will themselves melt in the fire which is intended only to 
 harden them; but this is owing to an excess of soda, pot- 
 ash, limestone, or other flux, any one of which ingredients 
 may help to convert the clay, when burnt, into a sort of 
 opaque glass. It must not be supposed that, merely be- 
 cause they may all be moulded, all clays are essentially 
 of the same kind and equally unlike other minerals. There 
 are, for example, various degrees of plasticity, some very- 
 complete, others very imperfect. It has been found, 
 generally, that pure clays, free from all foreign ingre- 
 dients except pure silica sand, are the most manageable 
 and the best that can be used, since they are not only 
 more easily worked, but the hardest and most beautiful 
 after burning. 
 
 Common brick clay fairly illustrates the general pro- 
 perties of the whole group. Some of the best brick clays 
 contain a great deal of sand, and enough oxide of iron to 
 color them deeply. The dark color of such clays is due 
 also, in part, to minute particles of carbon derived from 
 vegetable matter with which they are mixed; but the 
 material that produces the deep bright red so common 
 w'Ji burnt bricks is iron, and before burning is generally 
 of a dirty yellow or brown tint. 
 
 Besides carbon and iron, and a good deal of sand, brick 
 clay contains lime, potash, and soda. Of all these the 
 less there is the better is the clay, the less risk is there 
 of the bricks running together in the kiln, and the harder 
 and firmer will they be ultimately. It might be thought 
 
CLAY AND ITS VARIETIES. 65 
 
 that too much sand would be injurious; but this is not 
 the case. some of the best clays for burning containing 
 the largest proportion of sand. The iron, or rather oxide 
 of iron, may also be abundant without injury. 
 
 Very fine clays occur in small quantities in some parts 
 of the country, especially near coal-beds, from which can 
 be made bricks which resist any amount of heat in a 
 wind-furnace. These are the fire-clays, and their pro- 
 perties are owing to the almost entire absence of the 
 alkalies and the presence of but little iron. They are 
 often loaded with bitumen, which of course disappears 
 in the kiln where they are burnt. Stourbridge clay 
 from near Oxford, other clays near Newcastle, and others 
 again near Glasgow, are all celebrated for making those 
 bricks which best resist intense heat. They are called 
 fire-bricks, and are made with much greater care than 
 common bricks. Besides the careful working that such 
 clays require before using, they must be exposed for a 
 long time to the air after being taken from the earth, for 
 unless thus seasoned they cannot be depended on. A 
 good deal of the terra-cotta work, used commonly enough in 
 buildings and garden-terraces where ornament is required 
 at small cost, is made of these superior varieties of brick 
 clay; but they are all subject to the great disadvantage 
 of shrinking. This they do very much and very un- 
 equally, while undergoing the intense heat of the kiln 
 necessary to bake them. 
 
 Potter's clay, of a blue color and excellent quality, is 
 obtained from the little peninsula called the Isle of Pur- 
 beck, on the Dorsetshire coast. It is also found else- 
 where, and its peculiar value depends on the composition. 
 
 6* 
 
66 THE STONES OF THE BOOK. 
 
 Some kinds, without much sand, and of very uniform 
 texture, are adapted for the artist's use as modelling-clay ; 
 and these, if burnt, are remarkably smooth and beautiful. 
 Other kinds, without iron, make tobacco-pipes, while the 
 iron varieties are used for the common red pottery-ware 
 seen everywhere,. There are two kinds of pottery, one 
 being dark red and comparatively soft; the other, called 
 stone-ware, of pale color, and very hard. 
 
 China clay is a still finer kind. Formerly the finest 
 China clays were 'only known to occur in China and Ja- 
 pan, and they are still known by their Chinese names, 
 kaolin and pe-tun-tse. Large quantities are now obtained 
 from England, France, and Germany, and are much used 
 in the manufacture of the finer kinds of pottery and 
 porcelain. It is a striking thing to see and examine 
 some of the largest and most regular works where the 
 clay is dug, cleaned, and prepared for the market. This 
 clay is principally derived from Cornwall and Devonshire. 
 The process of cleaning and separating the clay from 
 sand and dirt is carried on in pits, where the raw 
 material is conducted by water and allowed to settle. 
 When afterwards dried, it is cut into bricks and sent to 
 the Staffordshire potteries. The operation is tedious, 
 many months elapsing, even in favorable weather, before 
 the clay is ready ; for it is extremely necessary that the 
 material sent should be as pure as possible. 
 
 There is a kind of clay found in Tuscany, not far from 
 Sienna, and also in France, which has a large admixture 
 of magnesia in its composition, and from which bricks 
 may be made. When either dried or burned, these bricks 
 are much lighter thau water, and they are also very effi- 
 
CLAY AND ITS VARIETIES. 67 
 
 cacious in resisting heat. The common Bath scouring- 
 brick, used for various purposes, is made in the same way, 
 and from somewhat similar materials. 
 
 Fuller's earth is another clay possessed of some curious 
 properties. It consists of nearly twenty-five per cent, of 
 water, dissolving almost entirely when mixed with water, 
 and melting when exposed to heat. This clay absorbs 
 grease very readily, in spite of its water, and is much 
 used in cleaning or fulling cloth. For this reason it is 
 called fuller's earth. 
 
 Some of our clays in England are valuable for pur- 
 poses that at first they would seem hardly fit for. Thus the 
 lias, or " blue lias" a common rock in the middle of Eng- 
 land, is particularly useful in the manufacture of cement. 
 It is a clay which contains much limestone, and burns 
 into a kind of lime, which when made into a mortar sets 
 rapidly in damp air, and even under water. It is thus 
 extremely convenient for building purposes; and the 
 mortar thus formed is called hydraulic cement. It is 
 made from impure clays and limestones, the peculiar pro- 
 perties for which it is valued depending on the presence 
 of foreign substances, so that the impure clays are more 
 valuable than those kinds which are more free from 
 foreign admixture. 
 
 Among the blue clays of the Lias, and below them, 
 are certain slaty beds, from which the alum of commerce 
 is obtained. The coast of Yorkshire near Whitby is one 
 of the places where this manufacture is largely carried 
 on. It might have been thought that alum has little to 
 do with clay : this is not so, for the one is derived from 
 the other; and, as we have already had occasion to re- 
 
68 THE STONES OF THE BOOK. 
 
 mark, the apparent impurities and foreign matters in clay 
 are materials of value in certain important manufactures. 
 
 It will be evident, then, that the ordinary clays under 
 our feet, forming the soil or subsoil of the earth, contain 
 materials of great interest, which are often largely em- 
 ployed for manufacturing purposes. From some such 
 clays we make bricks, an admirable substitute for stone 
 as a building material in our climate; from others, ap- 
 parently little different, we make pottery and porcelain ; 
 from others, again, cements are manufactured; while 
 some yield alum by elaborate chemical preparation. 
 
 These clay-beds do not (like the limestone) show any 
 marks of having been formed by animal or vegetable 
 help, for clay is not a substance that enters directly into 
 the composition of living beings ; and the expressions 
 often made use of in reference to clay as an emblem of 
 mortality are not really very applicable. A vast amount 
 of decomposition and recomposition must, in fact, go on 
 before any kind of substance resembling clay enters into 
 the human frame, or the frame of any animal, as a com- 
 ponent part; and even then the essential elements are very 
 small in amount. Carbon in abundance, and lime, and 
 iron, and even some silica, are traceable in the structure 
 of living tissue, but of clay properly so called (pure hy- 
 drous silicate of alumina) there is none. 
 
 But although this is certainly the case, it is not the 
 less true that clay plays a part in nature hardly exceeded 
 in real importance by any substance. As the soil and 
 subsoil in large districts of cultivated land, its conditions 
 and peculiarities affect all vegetation to an enormous ex- 
 tent. If a clay soil be not well drained, so that the water, 
 
CLAY AND ITS VARIETIES. 69 
 
 when it gets down within the clay, remains for a long 
 time without a chance of absorbing fresh air, a thing 
 very likely to happen in undrained land, the result is 
 exceedingly injurious. 
 
 The moisture, then, instead of encouraging vegetation, 
 completely poisons it, becoming highly mischievous in- 
 stead of beneficial. In drained land, when the stiff clay 
 is treated with lime, or mixed with sand, or in any other 
 way rendered accessible to the water and prevented from 
 caking into bricks, a clay soil is good and useful. 
 
 Stiff clay retains water on the surface in pools, not 
 allowing it to pass down. Whenever, therefore, a bed of 
 such clay, covered by more open and porous rock, is laid 
 bare by a cliff or railway-cutting, or by the natural slope 
 of a hill, it is very likely that the water should come out 
 on the side of the cutting in natural springs. There are 
 very simple conditions also under which, when beds of 
 clay are bored through, or when borings through other 
 rock reach clay, there should be natural jets of water, 
 such as are called Artesian springs. 
 
 Although clay is not formed or separated by animals or 
 vegetables, still many beds of it contain fragments of 
 wood, shells, bone, and other substances, which serve to 
 show very clearly the circumstances under which the de- 
 posit was brought together. It is curious enough to find 
 among these many indications, and sometimes whole 
 skeletons, of animals of which all traces have long passed 
 away from the world of life. 
 
 Among the shells found in the Lias clay, and in an- 
 other bed, called Oxford clay, lying over it in some places, 
 there are various kinds that seem to have had a general 
 
70 THE STONES OF THE BOOK. 
 
 resemblance to the squids and cuttle-fish now living ; but 
 they were provided with a long pen or solid framework 
 different in shape from that of any yet found. The squid 
 now is a soft animal, having a plate of horny or solid 
 matter (generally limestone) for the sake of attaching its 
 muscular system. It has also a very curious apparatus 
 of claws for holding its prey, and a small receptacle of 
 ink, with a tube by which it can shoot out the ink and 
 darken the water. It is not a little curious to find buried 
 in the clay remains of ancient animals of the same kind, 
 such as the thickened and dried ink, the bag in which 
 it was preserved, the delicate little hook by which the 
 creature could touch any thing that came in its way, and 
 the tube conducting to the ink-bag, unemptied at the 
 death of the animal. 
 
 Yet more singular remains are found in the same bed. 
 Among them are entire skeletons of large lizards, shaped 
 like fishes, and evidently adapted to live almost entirely in 
 the water, if we may judge by the presence of fins and the 
 absence of legs. Of such animals we find occasionally 
 not only the hard bones and teeth, but the marks of a 
 soft skin and large fins, showing that the animal was not 
 covered with scales, and there are even the contents of 
 the stomach, with fragments of indigested, half-digested, 
 and digested food, and the bones of the latest prey that 
 had been devoured. 
 
 The parts of clay-beds that are mixed up with lime- 
 stone often contain other remains of animals, such as 
 might be expected in that mineral and not in pure clay. 
 Thus, fragments of coral, and little shells like those at 
 the bottom of the deeper parts of the Atlantic, are here 
 
CLAY AND ITS VARIETIES. 71 
 
 found, with scales and teeth of fishes and shells of un- 
 familiar animals. 
 
 The fragments of vegetation found in these beds are 
 generally water-worn or altered. They do not form good 
 coal; but some of them can be, and are, used for fuel 
 when no better can be had. Some of them are changed 
 into jet, and are valued for ornamental purposes. Much 
 of the clay thus loaded with organic matter, and black 
 or brown with bitumen, is now extensively used in the 
 manufacture of mineral oil. 
 
 The number of different beds of clay found in England 
 is very large, and they are characterized by very different 
 remains. Thus, at the mouth of the Thames, in the Isle 
 of Sheppy, are numerous fruits of tropical trees, with 
 bones of alligators, large serpents and vultures, and even 
 remains of monkeys, all buried together and lying over 
 the chalk. Inside the chalk range in Surrey and Sussex 
 there are other varieties of clay loaded with very minute 
 valves of a small fresh-water animal. Near Weymouth 
 there are clays, with bad coal, used in making pottery. 
 These clays are below the chalk; and others again, be- 
 low them, and on which they rest, are worked near 
 Oxford. These extend eastwards to Cambridgeshire and 
 Lincolnshire, and form the well-known Fen country, 
 out of which rises Ely, on a small island in the middle 
 of a vast level space of such clays. Peterborough is not 
 far off, proving that there must have been some attrac- 
 tion in monkish days to induce a settlement in these rich 
 but uncomfortable and aguish tracts of country. 
 
 The Lias, seen well on the coast at Lyme Regis in Dor- 
 setshire, and Whitby in Yorkshire, and extending through 
 
72 THE STONES OF THE BOOK. 
 
 the midland counties, is another great and thick clay 
 deposit; and others again are known in places further to 
 the west. 
 
 Each of these clay localities is remarkable for some 
 peculiarity by which its clay may be recognized. In 
 many cases the difference in the appearance of the 
 clays is well marked; but, if not, the remains of animals 
 found in them would decide the question. Thus, no 
 fragments of any of the curious and gigantic fish and 
 lizards are met with, except in the group of rocks be- 
 tween the chalk and the coal deposits, while the shells, 
 and even the corals and star-fishes, found in the clay- 
 beds of Herefordshire and Wales, are quite unlike those 
 of the deposits near the middle of England. 
 
 We have already said that, by piercing through many 
 of the clays, springs of water are arrived at which reach 
 or approach the surface. This occurs when the water 
 flows beneath sloping beds of which the uppermost is 
 clay, there being tolerably free communication with the 
 surface on the upper part of the slope, but no means of 
 escape for the water from the other end. In such cases the 
 water is under pressure, and when an opening is made it 
 will immediately rush up in the endeavor to find its level. 
 
 We have hitherto been regarding clay in its most 
 usual form, as a tough, elastic mineral, and a substance 
 which cannot remain hard after long exposure to wet. 
 Let us now look at it in another light. If we use clay to 
 make bricks, of which we build our houses, we also fre- 
 quently use slate to cover them ; and at the present time 
 large slates, under the name of slabs, are very extensively 
 used for making tanks, billiard-tables, &c., and for a 
 
CLAY AND ITS VARIETIES. 73 
 
 variety of other useful purposes. The only limit to the 
 use of slates and slabs is the power to supply them in 
 sufficient quantity at a reasonable price. They combine 
 so much hardness and toughness, with a perfectly flat 
 natural surface obtained with little trouble ; they are so 
 admirably adapted to withstand exposure of all kinds; 
 they are so little absorbent, and affected so little by heat 
 and cold, that for many purposes they could hardly be 
 replaced with advantage by any known contrivance. 
 
 England is rich in these, as in so many other sources 
 of mineral wealth; and some of the great slate-quarries 
 of North Wales, Cornwall and Scotland are among the 
 most valuable mineral properties in the world. 
 
 Slate of all kinds is, however, nothing more than clay 
 that has undergone an enormous squeezing. The slate 
 is hardly more pure or free from mixture with foreign 
 substances than the clay; but in some way or other it 
 has become so completely altered as to assume a curious 
 kind of half-crystalline appearance and condition which 
 no other known substance presents. To satisfy ourselves 
 that slate is nothing more than clay, we have only to 
 observe the surface of the ground in slate districts. In 
 those parts of the country where slates abound, the 
 roads, and even paths, are generally thick clay; for the 
 constant treading of feet and grinding of wheels on the 
 slate reduce it first to a fine powder, and this mixed with 
 rain produces common clay. But, on the other hand, it 
 is equally certain that slate is a very peculiar condition of 
 clay; for, without being actually ground up with water, 
 no amount of mere exposure to weather on the flat surface 
 seems to have much effect upon it. In its most remark- 
 
 7 
 
74 THE STONES OF THE BOOK. 
 
 able characteristic, also, it is singularly unlike clay, for it 
 splits with extreme readiness into thin films when struck 
 in one direction, although it always breaks with jagged 
 edges in every other direction. It is not necessary to 
 direct attention here to the nature of this peculiarity, as 
 it is so universally known; but, although probably only 
 the result of enormous squeezing, the change certainly 
 involves a considerable alteration in the arrangement of 
 the particles. By very simple and familiar means we can 
 reduce slate to clay; we cannot, on the other hand, make 
 slate out of clay by any forces that have yet been brought 
 to bear upon it. 
 
 The capacity of splitting, carried to so great an extent 
 in slate, is called its cleavage, and is a property possessed 
 in an imperfect degree by many minerals when they pass 
 into the crystalline condition. In the case before us, how- 
 ever, the clay can hardly be said to be altered otherwise 
 than in texture, whereas most minerals, when they be- 
 come crystalline, enter into new chemical combinations. 
 Slate is thus an exceptional mineral. 
 
 Few simple minerals exist in beds of clay, although 
 some are occasionally met with. Thus, in many places, 
 a peculiar substance called heavy spar, used in the arts 
 to adulterate white-lead, occurs in crystalline form in the 
 interstices of clay-beds, while transparent crystals of 
 selenite (sulphate of lime) are tolerably plentiful in some 
 of the beds. Hard lumps of the size and shape of a man's 
 skull, occurring irregularly in many clays, consist of im- 
 pure mixtures of carbonate of lime and clay. These are 
 called septaria, because they look as if they had been 
 split into divisions, or septa, the cracks being afterwards 
 
CLAY AND ITS VARIETIES. 75 
 
 filled up. Such lumps are often collected, and serve as 
 the foundation of hydraulic cement, which sets, or hardens, 
 under water. But, although there are these exceptions, 
 clay generally is a rock unfavorable for mineral wealth. 
 Slate, on the other hand, especially when near granite, 
 contains some of the richest and most valuable mineral 
 deposits, especially the ores of copper. 
 
 In addition to the minerals already alluded to, there 
 are numerous very striking and beautiful substances in 
 nature which are so very largely indebted to the clay 
 element as to deserve special remark. Thus the mineral 
 called felspar is also a silicate of alumina ; but either soda 
 or potash to the extent of fifteen per cent, is added to the 
 combination. 
 
 Now, as in one shape or other felspar and closely allied 
 minerals form the basis of all the granites, and also of all 
 the basalts and lavas, all over the world, it will be seen 
 that clay assumes a still greater importance than we have 
 yet attributed to it. From the natural destruction of 
 granite under certain circumstances are produced the 
 finest clays for the manufacture of porcelain j and from 
 the decomposition either of basalts or lava (the name 
 basalt being understood to mean the same as lava, but 
 employed when the volcano from which it was poured 
 out is absent, and all traces of its origin have disappeared) 
 the finest and richest soils are often obtained. Pumice, 
 as well as lava, is a modification of clay. 
 
 Even some precious stones, in addition to the ruby and 
 sapphire, belong to our vulgar clays ; for the garnet and 
 carbuncle are silicates of alumina and lime ; emeralds are 
 silicates of alumina, combined with a rare earth called 
 
76 THE STONES OP THE BOOK. 
 
 glucina, and beryl is a mere modification of emerald. A 
 vast variety of comparatively rare minerals have also a 
 similar composition, including all those common in vol- 
 canic districts, all volcanic ashes and minerals thrown 
 out during eruptions, and those also which are afterwards 
 found in the clefts and cavities of the hardened masses. 
 
 Wonderfully varied, then, are the forms and uses of 
 clay, and the natural combinations of mineral substances 
 of which clay is an essential part. The solid foundations 
 of the earth, or at least all those most solid masses seen 
 near the surface, are in a great measure due to it. Huge 
 mountain-masses, covered or flanked with thick envelopes 
 of limestone, are often, to a depth quite unknown, made 
 up almost exclusively of minerals and rocks of similar 
 origin. They put on various shapes, and are known by 
 many names. Our streets are paved with them, and 
 some of the most enduring monuments of all ages are 
 chiselled out of them when they have become crystallized 
 into granites and porphyries. Our houses are roofed and 
 partly furnished with them, and our schoolboys write 
 upon them. Large tracts of country present them at the 
 surface as the common vegetable soil. Our jewellers 
 work them up into ornaments for the person, as garnets 
 and emeralds, beryls and carbuncles. The real ultimate 
 difference in composition in the case of all these minerals 
 is wonderfully small, while the appearance and all the 
 essential characteristics are as distinct as can well be 
 imagined. 
 
 And so it is everywhere in Nature. She works gene- 
 rally on a large scale with few materials, modifying them 
 and preventing monotony by the occasional introduction 
 
CLAY AND ITS VARIETIES. 77 
 
 of small quantities of other substances having different 
 properties. A little iron or manganese, a small propor- 
 tion of some rare earths or alkalies, or a few grains of sub- 
 stances whose effect we cannot trace, suffice her for the 
 production of a myriad of curious and useful modifications 
 of sand, limestone, and clay; and thus it is that the 
 essential ingredients of clay, slightly added to, form 
 numerous important minerals and rocks that we should 
 never think of comparing with clay, were we not obliged 
 to admit the near relation that exists between them. 
 
 Clay, then, is one of the essential and abundant com- 
 binations with which Nature works. She works rarely 
 on a large scale with the simplest forms of matter, and 
 never with those substances that are exceedingly com- 
 plicated. The great results are produced with a few 
 mixtures of two, three, or four elements, and of these 
 the mixture we call clay is one of the most frequently 
 and largely used, and one that produces some of the mosfc 
 complicated and grand results. 
 7* 
 
er % $n\\ti\. 
 
 CHALK. 
 
 A RIDE over the fine breezy downs near Brighton, or a 
 visit to the chalk hills north of London, is a pleasant 
 treat to any one who can appreciate pure bracing air, and 
 is able and willing to recognize the peculiar beauties and 
 characteristics of English scenery. There is a soft swell- 
 ing undulation about our chalk not elsewhere seen, a 
 smooth outline of richest green through which the white 
 rock constantly peeps, and at intervals a wide hollow 
 sweep of that dead creamy white which we know by ex- 
 perience to mark the pit from whence chalk is being dug 
 or has lately been removed. Let us go into one of these 
 pits, or, if the reader prefers, let us place ourselves in 
 imagination in a boat under the broad arch of some of 
 those bays at the back of the Isle of Wight, with the 
 picturesque Needles rising like ruined columns out of the 
 blue waves. Everywhere the facts are the same, a uni- 
 form mass of white soft rock, marked with lines more or 
 less removed from the horizontal, and occasionally thin 
 strings of black flint indicating these lines with surpris- 
 ing and picturesque regularity. If we travel round the 
 English coast, or into the interior of the country, we find 
 this same chalk very widely ranging. We ought to be 
 proud of it, for one of our island's names, ALBION, is 
 78 
 
CHALK. 79 
 
 derived from its appearance. It forms the Shakspeare 
 cliff at Dover, and the cliffs at Ramsgate and Margate. 
 Beechy Head consists of it. It shows itself at Cromer, 
 in Norfolk, and at Flamborough Head, and is seen in all 
 its characteristic features, crossing the Isle of Wight, and 
 standing out beyond it, as we have said, in isolated pin- 
 nacles of extreme beauty. We find it in Salisbury Plains, 
 in the North and South Downs, in Berkshire, and in the 
 Hertfordshire and Cambridgeshire hills. We pass through 
 it in many of our railway-cuttings. We dig into and 
 through it for water, and we quarry it for making lime, 
 and other purposes. We write with it; we even occa- 
 sionally build with it. 
 
 Let us examine it somewhat minutely. We all know 
 its usual color, its soft texture, its purity when burnt for 
 lime. Most of us know that numerous shells, fragments 
 of star-fishes and corals, and even perfect skeletons of fish 
 covered with scales, are occasionally found in it. It is 
 very picturesque, very characteristic, very useful, and 
 contains very curious things. The shells that we find in 
 it are of many kinds, some almost exactly like common 
 shells of the sea-shore, some very unlike those, and evi- 
 dently belonging to races extremely different. There are 
 fishes in it not much like our sea-fishes ; there are bones 
 like birds' bones, which, however, on careful examina- 
 tion and comparison, turn out not to have belonged to 
 birds, but to have supported in the air flying reptiles, 
 some of them larger than the largest albatross; there are 
 other bones that have not yet been found in England, 
 proving that very large reptiles of other kinds lived when 
 the chalk was formed. 
 
80 THE STONES OF THE BOOK. 
 
 But all these are comparatively rare; whereas, if we 
 take up any fragment of chalk from any part of the 
 mass, and make a careful examination of its particles 
 under the microscope, our eyes are opened to a fact ex- 
 ceedingly remarkable, namely, that all this large mass, 
 often several hundred feet thick, and occupying so large 
 a part of the surface of our island, seems to be one heap 
 of very minute shells, either whole or broken, once be- 
 longing to many varieties of a very few species of small 
 animals, such as those now found at all depths, but 
 chiefly abounding in the deepest profundities of the At- 
 lantic Ocean. Powdered chalk, or chalk mixed with 
 water and reduced to a pulp, is also wonderfully like the 
 mud from coral lagoons in the West Indies; but a large 
 part of it seems absolutely identical, when examined 
 under a powerful microscope, with what is called oaze, 
 the mud brought up, in a state almost tenacious and 
 pasty, from the bed of the North Atlantic Ocean. In- 
 deed, it would seem that after this oaze has had time to 
 allow its particles, long compressed by the weight of the 
 vast column of overlying water, to attain their natural 
 state under the diminished pressure at the earth's 
 surface, it is absolutely undistinguishable from powdered 
 chalk. 
 
 Very unlike the other limestones in texture and some 
 of its properties is this chalk, although it agrees almost 
 accurately with fine marble in its chemical constitution. 
 It is a nearly-pure carbonate of lime j the particles being 
 minute, and only held together by adhesion, not cemented 
 or crystallized in any degree whatever. t This condition 
 explains some of its peculiarities, such as its earthy tex- 
 
CHALK. 81 
 
 ture, allowing us to use it for writing or drawing, and its 
 extreme absorbency. In its driest state as a solid it 
 contains a good deal of water, which cannot be removed 
 by exposure to moderate heat, but when saturated a 
 block measuring twelve inches every way will contain two 
 gallons of water, very nearly one-third part of its total 
 content, and about the same proportion that is contained 
 by soft loose sand. 
 
 From its actual composition and its contents, there can 
 be no doubt that chalk was formed at the bottom of 
 water, and, in all probability, tolerably deep and smooth 
 water. It has undergone little change since, for the 
 particles of which it is built up lie side by side, appa- 
 rently as they were originally placed. Here and there are 
 threads of crystal or calc-spar, and occasionally bands of 
 black flints, sometimes touching each other, sometimes 
 asunder; but these are not rolled like the flints found in 
 the gravel, and the chalk that touches them is generally 
 precisely similar to the rest of the deposit. 
 
 The position and form of the hard angular flints may 
 also be accepted as proof that they were produced where 
 they are, and have never been removed since their crea- 
 tion. The evidence of this is indeed quite as good as 
 that by which we judge from the position and form of the 
 rounded pebbles of the gravel-beds that they are due to 
 the mechanical force of moving water. Gravel is a col- 
 lection of rolled pebbles and sand, while the flints in 
 chalk have never been rolled for a single instant. We 
 have only to look at them to be sure of this. The whole 
 mass of chalk is probably a deposit in deepish water but 
 little disturbed, and the flints do not seem to have been 
 
82 THE STONES OP THE BOOK. 
 
 deposited in the same sense as the chalk has been. They 
 do not seem to have existed at any time as mud j and to 
 understand them we must look for some other origin. 
 
 Making use once more of the microscope, we may 
 learn something that will throw light on this inquiry. 
 The examination of thin slices of flint reveals the same 
 truth as that often indicated on a larger scale visible to 
 the unassisted eye, namely, that these curious black 
 stones contain within their substance sponges or other 
 marine bodies. Not unfrequently we find the spine of 
 some old sea-urchin or sea-egg sticking out from an 
 unworn and unremoved flint; occasionally a shell is 
 there ; very frequently there is a peculiar structure re- 
 minding us of the sea-anemone; and now and then are 
 corals. Some flints are hollow in the middle, the hollow 
 being partly filled with crystals of the same substance, 
 the crystallized flint (silica) projecting inwards, or some 
 small detached stone, with a rough, spongy surface, being 
 loose in the middle. Every thing seems to prove that 
 the flints were formed by chemical agency, brought about 
 during the temporary stoppage of a deposit of chalk-mud, 
 and while the pause admitted of a multitude of sponges 
 and other marine forms of life being accumulated on the 
 ocean-floor. Perhaps some eruption of hot water, charged 
 with silica, may have taken place from submarine vol- 
 canoes. The number of beds of flint is very variable in 
 different places, many being often observable in a single 
 cliff or quarry, while elsewhere a great thickness of chalk 
 exists without any. The flints are generally lying on 
 the ancient floor of chalk, but occasionally they occupy 
 cracks and fissures in the completely-formed deposit. 
 
CHALK. 83 
 
 The way in which this curious accumulation of flint was 
 originally produced in the mass of the chalk remains, as 
 we have already seen, a mystery; nor is it quite manifest 
 why the beds of flint are sometimes regular, sometimes 
 quite irregular, and sometimes altogether broken up. 
 Whatever the reason may be, it would seem impossible to 
 suppose that the whole process of the deposit of chalk- 
 niud, chiefly by marine animals, and of flint hardening 
 on sponges and soft animals, can have been completed 
 without the lapse of a very long period of time. 
 
 But the fact that chalk is met with at such elevations 
 as Dover, and Beechy Head, and the Surrey hills, is an- 
 other startling fact. Originally deposited at the bottom 
 of an ocean, the mud of former times is now a solid 
 mass, several hundred feet thick, no longer near the sea, 
 but composing the whole of the land, at various eleva- 
 tions, in many parts of England, as soft chalk, and, in 
 a somewhat harder state, in Poland, Moldavia, and the 
 Caucasus. Over all these countries then, at any rate, 
 there was sea, and perhaps deep sea, when the chalk was 
 deposited, although some of them are now in the centre 
 of continental land. Of the land of those days we will 
 not now speculate. 
 
 The bedding of chalk, marked very distinctly in many 
 places, is by no means generally horizontal, as we know 
 it must originally have been. Certainly, a deposit of fine 
 mud at the bottom of water can only have been produced 
 in parallel and horizontal planes; for whatever the form 
 and irregularity of the ocean-floor, or the strength and 
 direction of marine currents, an impalpable mud must 
 certainly have been originally accumulated at a dead level, 
 
84 THE STONES OF THE BOOK. 
 
 the mud first filling up the hollow places, and then 
 covering all over with a succession of thin films. But 
 now the beds, though parallel to each other, are no longer 
 horizontal : generally, they are tilted up at an angle of 
 several degrees. The chalk of the North Downs has a dis- 
 tinct tilt towards London, and that of the South Downs 
 towards the coast of the British Channel; while in the 
 Isle of Wight and the coast of Dorsetshire, not far off, 
 the beds are either curved over in magnificent and lofty 
 arches, as seen at Scratchell's Bay, near the Needles, or 
 are absolutely vertical, as at Culver Cliffs, on the east 
 side of the island, between White-cliff and Sandown 
 Bays. 
 
 The white chalk-cliffs of the south coast of England 
 arc, as it were, repeated and reflected by an almost 
 similar series on the opposite shores of the British 
 Channel, between Calais and Havre; and there cannot 
 be a doubt that the mineral deposit is continuous, and 
 that the separation of England from the Continent by the 
 waters of the Channel does not separate the chalk, which 
 is only covered over and concealed, and not entirely eaten 
 through. But chalk, though seen in abundance on the 
 French coast, soon passes into a harder limestone in the 
 interior of France, losing its peculiar texture towards the 
 south, beyond the valley of the Seine. The actual com- 
 position of chalk and of the limestones that it passes into 
 is, however, nearly the same; and there would seem not to 
 be much change in the shells and other remains of ani- 
 mals with which it abounds, although the mineral pecu- 
 liarities of the rock are quite lost. The fact is, that the 
 
CHALK. 85 
 
 passage of chalk into limestone is an event altogether 
 modern compared with the deposit of the chalk-mud. 
 
 Chalk is not only sometimes covered up by other rocks, 
 such as clay, sand, and gravel, but also by the waters 
 of the ocean, which between England and France conceal 
 it from observation. In either case, by very simple 
 means, we can satisfy ourselves of its presence by the 
 boring-tool, the dredge, or the diving-bell. 
 
 With regard to the solid accumulations, it is not diffi- 
 cult to prove that there are, in various places, small 
 patches of such substances; but in the great valley of 
 the Thames these entirely cover a triangular area, mea- 
 suring nearly a hundred miles in its longer direction 
 from Hungerford to the Essex coast, the base of the 
 triangle, between Ipswich and Sheppey, being fifty miles, 
 and the area enclosing more than two thousand square 
 miles of country. At various localities within this wide 
 area, the chalk has actually been reached by boring-ope- 
 rations carried on for water; and the thickness of the 
 deposits amounts, here and there, to more than a thou- 
 sand feet. A somewhat similar, but less extensive, por- 
 tion of the chalk is covered by similar deposits near 
 Southampton. 
 
 On the other hand, there is a large area surrounded by 
 chalk-hills clearly traceable from Dover, along the line 
 of the North Downs, as far as Alton, in Hampshire, 
 there rounding and connecting with the South Downs, 
 which terminate in the sea at Beechy Head. On the 
 opposite shores of France, the chalk-hills in like manner 
 recede. Within this range of chalk-hills are sands and 
 clays, but no chalk is found either on or beneath the 
 
86 THE STONES OF THE BOOK. 
 
 surface. The area thus excluded and cut out from what 
 would otherwise be (as it probably once was) a continuous 
 bed, is not very different in extent from that concealed 
 by the clays on which London is built. 
 
 Across the German Ocean, chalk is found at Faxoe, in 
 Denmark ; and a soft limestone, of the same kind, with 
 the remains of similar animals, in a similar state, on the 
 banks of the Meuse, in Belgium. But true soft chalk is 
 here replaced by a crumbling mass, while in France, as 
 already stated, it becomes harder. It is singular that, 
 in its integrity, the chalk is almost confined to our own 
 island, and, indeed, to the eastern side of it. 
 
 When holes are bored into it, or cuttings made through 
 it, chalk is found to be throughout very uniform in 
 texture. It is also extremely and uniformly absorbent of 
 water. 
 
 In the interior of a large mass of chalk, after a wet 
 season, if the whole becomes saturated, it is certain that 
 any empty spaces or cavities that exist will be also quite 
 full; and if these are pierced by bore-holes, and the water 
 pumped out, a large supply may be procured. All the 
 water that falls on the surface, either of the chalk itself 
 or the rocks near it, will almost inevitably be conveyed 
 into the rock, which, indeed, acts like a sponge, besides 
 being everywhere open at the surface by many small 
 cracks. The mass of the chalk thus acts as a kind of 
 large reservoir, receiving the rain that falls, retaining 
 it for a time, distributing it in the earth's interior, and 
 at length giving it out again for the benefit of men and 
 animals, either from natural or artificial springs. 
 
 In its ordinary state, true chalk is of little or no value 
 
CHALK. 87 
 
 as a building-stone, owing to its softness and the readi- 
 ness with which it is reduced to powder by exposure to 
 damp air and frost. Still, it has been used for interior 
 ornamentation, owing to the great readiness with which 
 it can be cut; and instances of its employment in this 
 way may be found in many of our cathedrals in the East 
 and South of England. Methods have been suggested by 
 which the specimens in certain cases should be hardened, 
 so as to be no longer subject to injury on exposure to the 
 air. It can then be used for inside building and decora- 
 tion with great advantage. 
 
 Most of the chalk is, as we all know, remarkable for 
 its peculiar dead-white color, although occasionally there 
 are tinted varieties. The chalk near Flamborough Head, 
 in Yorkshire, is naturally red; but the colored chalks 
 used for drawing are artificial productions. 
 
 The chief use of chalk is in the manufacture of lime, 
 whether for mortar or for dressing land. For these pur- 
 poses the consumption is very large, the chalk being 
 usually burnt in kilns in the pit or quarry from whence 
 it has been hewn, to avoid cartage. 
 
 The lime thus obtained is very pure, but this is not 
 any particular advantage ; as lime made from limestones 
 having a little clay, or sand, or iron, makes a mortar 
 which sets more rapidly and is harder than that made 
 from pure carbonates of lime. Chalk is also used occa- 
 sionally without burning to improve certain kinds of soil, 
 and is the only kind of limestone of much value for such 
 purposes. 
 
 When we seek for the origin of chalk and flint, and 
 the circumstances that would seem necessary for their 
 
88 THE STONES OF THE BOOK. 
 
 formation, the conclusions we are forced to accept are 
 almost overwhelming. True it is that we are speaking 
 of a rock very uniform in its texture, and comparatively 
 limited in its range, though really much more widely 
 spread than one might suppose from the hardening it has 
 in some places undergone, which modifies its usual ap- 
 pearance. An inch cube of this substance would contain 
 countless millions of fragments or of complete shells of 
 one small tribe of animals, and would be almost identical 
 in its contents with' a corresponding cube of mud taken 
 partly from the bottom of the Atlantic, anywhere between 
 Valentia and Newfoundland, and partly from the oaze or 
 mud at the mouth of the Thames. Since, however, the 
 Atlantic floor, thus covered, measures at least a thousand 
 miles from east to west, and probably several hundred miles 
 from north to south, its thickness, probably irregular, 
 being quite unknown, so the area of country occupied 
 by chalk must be measured by hundreds of miles each 
 way, and its thickness is known to amount to from six 
 hundred to a thousand feet. Think of the number of 
 individuals required for such vast accumulations ! Truly, 
 the sands on the sea-shore are as nothing in comparison, 
 and might be taken as the unit in so marvellous an arith- 
 metic! All ordinary descriptions of number fade into 
 insignificance in comparison; and we must admit that 
 Nature has not adapted our faculties even to conceive and 
 comprehend such combinations of the most minute atoms 
 into the largest mountain-masses. And yet it is clear 
 that time alone is needed to render possible the results 
 we see in the chalk, even assuming that its whole mass 
 was formed as the bed of an open ocean of deep water 
 
CHALK. 89 
 
 Rapidity of growth and accumulation correspond with 
 minuteness of organization. The smaller the animal, the 
 more efficacious does it seem in producing large and 
 abiding results; so that for every bone of reptile there 
 are thousands of visible shells, and for every shell millions 
 of these little invisible habitations of the simplest of 
 Nature's productions. 
 
 What thoughts crowd upon one, in thus contemplating 
 so simple an object as a chalk-pit! Here we seem to 
 possess unchanged, except by being lifted up into sight 
 for the convenience of study, a section of an old ocean- 
 floor. Here are the proofs of ever-busy, stirring life, 
 most busy, and most powerful and influential, when act- 
 ing in its simplest mode, and producing an infinite repe- 
 tition of similar objects. Not, indeed, that these are 
 monotonous in their resemblance, for here, as every- 
 where, the type or general plan is the same, but each 
 individual possesses its own personal existence, and some 
 peculiarity that distinguishes it from its neighbor and 
 brother-atom. 
 
 There seems nothing now going on strictly analogous 
 to the formation of beds of flint alternating with the fine 
 chalky mud on the Atlantic ocean-floor. In this the 
 analogy fails, and we are forced to assume that the flint, 
 in a pasty state, or having the consistence of a jelly (as 
 is the case in certain combinations with potash), was only 
 an occasional deposit, no example of it being at present 
 known to us. 
 
 Very rarely indeed rolled pebbles of granite or other 
 distant rock have been found buried with the chalk, and 
 forming part of it. Out of the line of drifted icebergs, 
 8* 
 
90 THE STONES OF THE BOOK. 
 
 there would be but few stones and pebbles conveyed now 
 into the Atlantic, a few hundreds of miles from the land : 
 so that we need not be astonished that such an event was 
 equally rare in former times. What goes on now is, pro- 
 bably, only a repetition, with small variations, of previous 
 events ; and in G-eology, according to the best experience 
 of scientific observers, we arrive at the conclusion, arrived 
 at long ago by King Solomon, that " there is nothing new 
 under the sun." 
 
 The chalk must -be regarded as one deposit of a great 
 multitude, a mere unit in a host. But it abounds with 
 interest and instruction ; it illustrates a recent deposit of 
 the most curious kind; it is itself very peculiar, and un- 
 like most others, and it well deserves careful attention. 
 Moreover, it is essentially an English rock, and produces 
 a very distinct scenery in those parts of the country where 
 it prevails. Being strongly marked and easily recognized, 
 and also pretty widely spread, it forms an admirable start- 
 ing-point for the young geologist, while its position in the 
 great series of rocks adapts it still further for this edu- 
 cational use. 
 
LIMESTONES AND MARBLE. 
 
 CHALK is a very soft kind of limestone; but being 
 rarely used as a stone for any purposes of construction, 
 and generally burnt to turn it into lime, it is convenient 
 to separate it from limestones, as we have done, by treat- 
 ing it in a chapter by itself. Limestones differ from 
 chalk in being more consolidated and less earthy, having 
 while buried in the earth become to a certain extent 
 altered by a process which, if continued long enough, 
 would turn them into crystalline minerals. Many of the 
 limestones, indeed, are already partly crystalline, either 
 here and there in the bulk of the rock, or else in cavities. 
 Crystals are often seen shot out, as it were, from the 
 walls of a cavity, although all around there is no appa- 
 rent change in the mixed fragments of shells and fine 
 particles of sand of which the stone was evidently made 
 up. In proportion 'as limestones are of closer grain, of 
 firmer texture, and more compact, they approach to the 
 condition called semi-crystalline ; and thus they pass, by 
 successive stages, into marbles, which are true crystalline 
 limestones. 
 
 Limestone is, as every one knows, a common mineral 
 enough in England, very large parts of the country con- 
 sisting of little else. Vast quantities are also found, not 
 
 91 
 
92 THE STONES OF THE BOOK. 
 
 only in most parts of Europe, but generally throughout 
 the world. There are, however, some large districts in 
 which this rock is absent, and others where it is not to 
 be obtained very near the surface ; and as lime is wanted 
 not only for building purposes, as stone or mortar, but 
 for mixing with and forming part of soils, the places 
 where limestones are rare generally suffer much from the 
 absence of them. When it is remembered that all bone 
 consists chiefly of lime, and that birds require it to form 
 a hard coating for their eggs, the necessity of this mineral 
 will be seen. It is useful to know how to recognize the 
 varieties. 
 
 There are two or three very different minerals generally 
 called limestones : one is the common carbonate of lime, 
 such as Bath and Portland stones used for building. 
 This kind passes by insensible gradations into marble, 
 having the same composition with the addition of some 
 impurities. Another kind is the magnesian limestone, 
 or dolomite, a mixed carbonate of lime and magnesia, 
 also a building-stone, and unfortunately very notorious as 
 being the stone of which the Houses of Parliament were 
 built, concerning whose early decay there is so much 
 discussion at present. Gypsum, or alabaster, much used 
 in a burnt state in making plaster of Paris and other 
 varieties of plaster, and occasionally sculptured as an 
 ornamental stone, is a third kind ; but this is a sulphate, 
 not a carbonate, of lime, and has, therefore, a distinct 
 chemical composition. The two first varieties, when 
 burnt, yield a hardish, compact substance known as quick- 
 lime, but the last yields plaster of Paris, an extremely 
 fine powdery material, having very different properties. 
 
LIMESTONES AND MARBLE. 93 
 
 Quicklime, mixed with water, heats, swells, and falls to 
 powder; but plaster of Paris absorbs water, and imme- 
 diately sets and becomes permanently hard. The differ- 
 ence between the common and magnesian limestones and 
 gypsum is, therefore, practically very essential. 
 
 Many of the limestones, such as those used for build- 
 ing, are of a grayish and dirty white or cream color, of 
 very uniform texture and tolerably hard ; some, like those 
 found in Derbyshire and Devonshire, are compact enough 
 to take a high polish, but being colored and veined are 
 of no value for artistic purposes, though much used for 
 furniture and decoration, for which they are well adapted. 
 Others, again, such as the Carrara and Parian marbles, 
 are used in sculpture, and are known as statuary marbles. 
 These latter are of the most exquisite white tint, and show 
 a texture like loaf-sugar, or even sometimes like virgin wax. 
 
 Of building-stones, again, there is an immense variety, 
 some of them being hard and others soft, some brittle 
 and others tough, some full of shells, some made up of 
 little round egg-shaped particles like the roe of a fish (polite 
 or roe-stone], some of sandy grains easily separated. Most 
 of them absorb water very readily and in large quantity, 
 and when exposed in building, where the weather affects 
 them, or where they are subject to alternations of wet and 
 dry, heat and cold, they are very apt to become rotten, 
 the sculptured and ornamental parts breaking off. 
 
 In England it is rare to find limestones of a dead-white 
 color like chalk and at the same time extremely hard and 
 close-grained. Such limestones, however, are common ; 
 enough in other countries, and are very valuable materials 
 for construction, as they are handsome and durable, ab- 
 
94 THE STONES OF THE BOOK. 
 
 sorbing but little water. Each country possesses its own 
 materials, and those of one district are by no means always, 
 nor are they usually, identical with those of another. 
 
 Most of the common limestones lie in beds of moderate 
 thickness, separated from each other by an intermediate 
 bed of clay or rubbish, or of stone valueless for building 
 purposes. Very often these beds lie horizontally, or 
 nearly so, and they are almost always parallel to each other; 
 but occasionally they are tilted at a high angle, a position 
 that must have been produced by some force lifting them 
 up from below after they had been hardened, and gene- 
 rally in such cases the beds are broken asunder and more 
 or less rotten near the point where the elevation took 
 effect. When limestones lie on the flanks of mountains, 
 or form mountain-masses reaching to the clouds, it seems 
 less difficult to see and understand the mode of action of 
 the force, and we even judge of its magnitude; but when 
 a large district is affected by moderate and very slow 
 elevations, it is not easy to trace the cause. 
 
 All limestones when in the earth contain a good deal 
 of water, and they are softer and more easily chiselled 
 when just removed from the quarry than after a few 
 months' exposure. When left exposed to dry air the 
 stone dries, and a hard crust forms upon it which resists 
 the action of weather; but if used at once, and subject 
 to the pressure which must act upon all stones in a build- 
 ing, before the stone has had time to consolidate, the 
 weather will generally have much more effect upon it. 
 
 Most of the stones in a quarry very near the top are 
 more cracked and destroyed than those taken from some 
 depth, so that many quarries now are completely under 
 
LIMESTONES AND MARBLE. 95 
 
 ground, the stone being worked out from the bed within 
 the bowels of the earth just as coal is removed from the 
 mine. One result of this method is that, with care, the 
 best bed and the best part of a bed of stone may be 
 secured ; but it is necessary to take precautions that the 
 stones thus brought out are properly dried before use, as 
 they will have undergone no chance of weathering until 
 removed into the open air. 
 
 An old quarry and a quarry where the stone is got in 
 the open air is a picturesque object enough ; the steep 
 face, the successive steps as one bed is worked in ad- 
 vance of another, the vegetation bursting out from all 
 the cracks and corners, and the half-decayed weathered 
 look of the parts where no work has been going on for 
 some time, are all objects on which the eye rests with 
 pleasure. In one place a huge crane is lifting large 
 blocks to a truck, in another a puff of smoke marks 
 where a recent blast has taken place ; while the approaches 
 to the quarry, with their rough roads and broken rails, 
 form a contrast with the surrounding scenery which is 
 eminently favorable to the picturesque. 
 
 Those quarries where the whole or most of the work is 
 carried on under ground and out of sight are far less 
 interesting. Opening often on the bank of a river or 
 canal, nothing is to be seen but a small tunnel or entry, 
 the wagons bringing out the stone, already reduced to 
 convenient sizes, and ready to put on the boats lying 
 alongside. Still, even here the eye rests with pleasure 
 on a certain contrast of Nature with Art, which rarely 
 fails to produce some effects pleasing to the lover of the 
 picturesque. 
 
yb THE STONES OF THE BOOK. 
 
 In many limestone rocks of large extent, there are 
 caverns or open spaces communicating with the outer 
 world. Among such caverns, those of Adelsberg in Ca- 
 rinthia, on the road from Vienna to Triest, arid the so- 
 called Mammoth Cave of Kentucky in America, are the 
 largest that have been described. The Peak cavern in 
 Derbyshire, the caverns in Yorkshire, Somersetshire, and 
 South Wales, those in Sicily, and Central France, and 
 Bavaria, and others in the Rock of Gibraltar, are well 
 known as objects of curiosity visited by strangers; and 
 some of them afford very curious facts for consideration. 
 These are of two kinds: one having reference to the 
 mechanics of the cavern, the way it was hollowed out, 
 and has been partly filled up with those wonderful appear- 
 ances called stalactites, and the other to the curious 
 remains of animals found frequently on and in the earthy 
 floor of the cave. 
 
 The extent of caverns is sometimes very great, and is 
 often quite incapable of being accurately determined. 
 The more interesting of them consist of a multitude of 
 passages, often narrow, too small, indeed, to allow a 
 human being to penetrate, but connecting large open 
 cavities lying far within the rock. They are often more 
 or less full of water, which enters and gets out of the 
 chain of caverns in a manner scarcely traceable. The 
 open spaces are sometimes large and lofty and well ven- 
 tilated, but sometimes they are smaller and nearly choked. 
 Nothing, indeed, can be imagined more irregular than 
 this chain of open cavities, running, perhaps, for miles 
 under the earth at various levels, with no reference to 
 any place or system that we can at all trace. Almost all 
 
LIMESTONES AND MARBLE. 97 
 
 imestones are exceedingly liable to be penetrated with 
 these irregular holes. 
 
 Within the cavern the walls of which are generally 
 worn and often smoothed, as if by the passage of water 
 there are often sheets, columns, and pinnacles of stone, 
 which, when undimmed by the smoke of lamps and 
 torches, are half transparent, and of the most brilliant 
 yellowish- white appearance. These hang down from the 
 roof, rise up from the floor, arrange themselves fantastic- 
 ally, as curtains, tables, or festoons, and even take the 
 forms of animals and human beings. They are of pre- 
 cisely the same material as the limestone walls of the 
 cavern, but are easily seen to be of different origin. By 
 a little examination it may be found that all of them 
 have been formed in connection with the drip of water; 
 the water, while penetrating through innumerable small 
 cavities in the limestone rock, takes up a part of the 
 mineral and carries it along, eating away its course, 
 partly chemically by dissolving the rock, and partly 
 mechanically by constant rubbing. When it reaches an 
 open empty cavity, where is a current of air, the water is 
 evaporated and the stone left behind. Such is the his- 
 tory of that variety of curious and beautiful appearances 
 seen in caverns, the magic fountains and organs, the 
 cathedral aisles and vaulted roofs, the drooping trees, the 
 crouching animals, the busts, and the apparent vegetation. 
 All these are nothing more than fantastic forms slowly 
 and gradually accumulated; and the wonderful things 
 told about them are due quite as much to the fancy of 
 the describer as to Nature herself. 
 
 The floors of such caverns are often nearly level and 
 9 
 
98 THE STONES OF THE BOOK. 
 
 hard, being repetitions of the same half- crystalline ma- 
 terial, and produced in the same way. The sheets of 
 limestone on the floor of the cavern are sometimes called 
 stalagmite, to distinguish them from the stalactites that 
 drop from the roof. In the limestone floor, in the mud 
 under it, and often in heaps not yet covered with stalag- 
 mite, there have been found, in many caverns, numerous 
 bones of animals. Some of these were no doubt wild 
 animals, that had used the cavern as a den; some were 
 certainly the prey -of wolves, hyenas, and other savage 
 tenants, which they had dragged into their lair, perhaps 
 for the benefit of their young; some, again, seem to have 
 been carried into the cave and buried there, when un- 
 usual floods of water had drifted river-deposits, mud, 
 bones, and other material from a distance, leaving it be- 
 hind in these sheltered places after the waters had re- 
 tired. When the bones thus found are carefully ex- 
 amined and compared with those of known species, they 
 are found to belong to races that are no longer common 
 in the adjacent country. Thus, in England and West- 
 ern Europe there are bones of hyenas and large bears, 
 of a kind of tiger, and of many other fierce carnivorous 
 creatures, only met with at present in Asia and Africa. 
 In Brazil, under similar circumstances, are bones of wild 
 animals equally different from the inhabitants of the 
 neighboring tropical or temperate land; and in Australia 
 there have been found remains of kangaroos and wombats, 
 much larger than, and very distinct from, those of the 
 present neighborhood. With the carnivorous monsters 
 in our English caverns are numerous bones of the ele- 
 phant and rhinoceros, and even of the hippopotamus, 
 
LIMESTONES AND MARBLE. 99 
 
 mixed with fragments of reindeer, and of a very large 
 horned deer, long since lost sight of among existing 
 races, as well as of large animals of the ox tribe. Every 
 . thing indicates great antiquity, and a different climate; 
 and yet with these strange associates are seen chiselled 
 flints, evidently human weapons, all buried at the same 
 time. The condition of the bones, the great proportion 
 of some one species in each cavern, the number of bones 
 and teeth. of young individuals not at all more injured 
 than the harder bones near them, and the fact that 
 many of the bones of the deer and oxen are much 
 gnawed, as if by the teeth of hyenas in the hyena 
 caverns, and not at all so when the cavern was apparently 
 otherwise owned, all seem to prove that the caverns had 
 long served as the dens of these wild and powerful 
 animals. 
 
 Limestone presents itself in nature under very dif- 
 ferent aspects. Crossing England diagonally, and owing 
 to various causes not much developed on the coast, the 
 peculiar features of limestone cliffs are not much seen on 
 our shores; but in the interior there are many fine and 
 some noble specimens of limestone-cliff scenery. In the 
 beautiful and wild valleys of the western part of York- 
 shire, in the Peak district of Derbyshire, and some of the 
 river-valleys of Derbyshire, especially near Matlock and 
 along the course of the Dove, the bold vertical faces of 
 compact limestone rock are grand and picturesque in the 
 extreme. Something of a similar beauty characterizes 
 the Chedder Rocks, and others adjacent, in the Men- 
 dips; and still more remarkable are the deep narrow 
 gorges and richly-clothed ravines of Linton, in North 
 
100 THE STONES OP THE BOOK. 
 
 Devon. These specimens of scenery are well contrasted 
 by the hilly parts of the middle of England, especially 
 near Cheltenham and Bath, where a much softer rock of 
 the same nature, but very different texture, presents a 
 correspondingly different appearance. No one who did 
 not carefully examine for himself would suppose that 
 the hills of Gloucestershire and Derbyshire were com- 
 posed of the same mineral; for it is difficult for two 
 minerals to be more distinct from one another than are 
 the limestones in these localities, in respect to color, hard- 
 ness, compactness, and mode of resisting or yielding to 
 the action of weather. 
 
 Almost all limestones may be found, on a little inves- 
 tigation, to be made up of beds of various thickness. 
 Between the beds there is often a thin plate of some 
 other material, or of the same material in a different form. 
 All, without exception, of the limestone rocks are also 
 more or less cracked ; so that water has access to the inte- 
 rior; and thus it is not to be wondered at that numerous 
 springs of water come out wherever these beds are cut off 
 abruptly, on a hill-side or cliff, and that in all limestone 
 districts the surface is dry, while water may generally be 
 had by digging. 
 
 The minerals found between beds of limestone, or 
 cemented with broken blocks in former cavities, and some- 
 times crystallized in cracks of the limestone, are of great 
 value. Almost all the lead and zinc used in commerce 
 are found in the shape of ores or stony minerals under 
 these circumstances; and often, at first sight, it would be 
 difficult for any one not familiar with minerals to distin- 
 guish some of the most valuable of these from valueless 
 

 LIMESTONES AND MARBLE. 101 
 
 stones. Even iron is found sometimes, in enormous 
 quantities, mixed up with limestone, and looking so much 
 like it that for a long time it has been regarded as a 
 mere variety. Tens of thousands of tons of iron-ore are 
 now obtained from beds that, a few years ago, were 
 looked upon only as poor and worthless limestones. 
 
 While chalk is made up almost entirely of the very 
 small shells of animals, of which thousands would be 
 required to bury a pin's head, most of the harder lime- 
 stones are equally remarkable for fragments of shells 
 and corals and other hard coatings of animals, which 
 are for the most part of much larger size. Such com- 
 mon shells as are cast up on every sea-beach will in 
 time, and by long accumulation, occupy an important 
 place even among rocks ; for, with water constantly run- 
 ning through them, they become at last firmly cemented 
 together. But it is chiefly by the work of the coral 
 animal that large mountain-masses of limestone have 
 been obtained. Coral, especially certain varieties abound- 
 ing in some tropical and warm seas, consists of a curious 
 mass of individuals, with one common jelly-like living sub- 
 stance connecting them. The whole mode of growth is 
 more like that of a plant than an animal, the individuals 
 resembling the leaves and flowers, while the common 
 central mass is the stem or trunk. These curious animals 
 are able, with great facility, to separate from the salt 
 water about them those few grains of limestone they 
 require; and these are immediately replaced, because the 
 sea washes over limestone, and quickly sucks up as much 
 as it needs when deprived of any part by animals. There 
 is thus a never-failing supply of lime in the ocean, and 
 9* 
 
102 THE STONES OF THE BOOK. 
 
 the little creatures we refer to have been pilfering in 
 safety from the very creation of the world till now. 
 What they take, however, they at once use, building up 
 with it a stony and almost imperishable framework, 
 which, so long as it is coated with living matter, does not 
 become worn or wasted. When myriads of these indi- 
 viduals collect together in a mass and secrete limestone, 
 they construct walls which rise to the lowest level of 
 low-water, commencing at the bottom of the sea at 
 some moderate depth. If every thing remains in the 
 same state, a fringe of coral soon forms round every part 
 of an island, or along the whole of a coast, that has once 
 been reached by the animals, except, indeed, where an 
 interruption exists, such as a river or stream of fresh 
 water of some magnitude entering the sea ; or some ex- 
 traordinary and abrupt submarine ravine prevents the 
 advance of the coral, by depriving it of a support to 
 build upon. Such fringes of coral are well known in 
 some parts of the world, especially within the tropics, 
 and in the warmer waters both of the Atlantic and 
 Pacific Oceans. 
 
 But besides these fringes of coral which, when the 
 animal dies, may, if not washed away, become coral lime- 
 stone there are other equally well-known districts, 
 where the coral extends to a very much greater depth 
 than the larger kinds are thought able to work in, the 
 extreme depth of coral having been found to amount to 
 many hundreds of fathoms, whereas the larger corals are 
 believed to die if removed even twenty fathoms deep. In 
 some way or other, it certainly seems that coral-beds can 
 even now be prepared, of great thickness, as well as 
 
LIMESTONES AND MARBLE. 108 
 
 covering a wide surface-extent; and if this is the case at 
 present, there is no reason why a similar result should 
 not have been obtained formerly. 
 
 Many of these remarkable and extensive limestones, 
 to which we are indebted for much of the picturesque in 
 English scenery, were beyond doubt the composition of 
 little animals, just such as those now building coral in 
 warm latitudes. The results may be seen and compared 
 together, and, in many cases, the whole form of construc- 
 tion and the peculiarities of the animals may be identified. 
 We are thus bound to admit the close resemblance be- 
 tween the present manufactures of the coral animal, and 
 those ancient and crystalline limestones that are now 
 quarried for building-stone, or those which are carefully 
 selected and set aside as furnishing marble for some of 
 the most elegant manufactures or the noblest works of 
 genius. 
 
 Limestones form the staple material of the flanks of 
 the Alps, and extend in still greater abundance east- 
 wards into Asia, scarcely any thing else being seen in 
 the Carpathians and the Caucasus. A large part of Italy 
 and Greece is also made of or covered with similar rock. 
 In these latter countries, marble often replaces common 
 limestone; and this seems owing to the vicinity of the 
 great disturbing forces exemplified in the elevation of 
 the mountain-chains to the North, and the frequent erup- 
 tion of melted rock and hot vapors from the important 
 volcanoes of the South, of Europe. Spain is not less re- 
 markable for its marbles and limestone rocks than France 
 and Italy; but they are less known, owing to the rarity 
 
104 THE STONES OF THE BOOK. 
 
 (till lately) of any commercial or industrial activity in 
 that country. 
 
 The second kind of limestone mentioned at the begin- 
 ning of this article that kind which is known to mine- 
 ralogists under the names gypsum and alabaster is very 
 different in many respects from the stones just described. 
 It is not often in regular beds of great extent, being far 
 more commonly found in large detached lumps. It is 
 very much softer than any of the building-stones, and is 
 either of a dead-white appearance, like chalk (but not 
 soiling a black surface), or else nearly transparent. It is 
 more frequently found with sandstones than limestones. 
 Large quantities of it are obtained from Derbyshire and 
 Nottinghamshire in England, and from deposits around 
 Paris, and in Italy near Florence. Egypt also abounds 
 with it. When pure, whether white or transparent, it is 
 often cut into vases, lamps, figures, and other ornaments, 
 some of which are of great beauty and value j but for the 
 most part it is burnt, and in that state sold to make 
 plaster of Paris and other plasters by various treatment. 
 
 There is another kind of limestone, quite different from 
 either of the two described, and often so hard as to be 
 mistaken for flint. It is found in pebbles in large quan- 
 tity in the gravels of Suffolk, and in beds in some other 
 parts of England. It consists of rolled bones and other 
 remains of animals, and is called by chemists a phosphate 
 of lime. When properly prepared, this stone serves as 
 an admirable mineral manure or dressing for land for 
 agricultural purposes. The pebbles thus used were at 
 one time called coprolites (abbreviated to cops), owing to 
 an idea entertained that they were petrified dung. Among 
 
LIMESTONES AND MARBLE. 105 
 
 them, however, we often meet with such things as ear- 
 bones of whales, parts of the backbone of whales and 
 sharks, bones of quadrupeds, and other things, that point 
 to them as being for the most part, like the common lime- 
 stones, due to animal life in its more complete form. 
 
 Such is an outline of some of the principal facts known 
 about limestones. We may sum up the account in a few 
 words, by saying that they are a group of stones of great 
 usefulness to man in almost all their varied forms, both 
 directly and indirectly; they are widely spread, they form 
 very picturesque and characteristic scenery, and they 
 contain mineral wealth. Most of them are directly due 
 to the influence of animal life at some period or other, 
 often very remote ; but they have since undergone a good 
 deal of change, and hardly now resemble what they once 
 must have been. Some, no doubt, are still soft and little 
 altered ; but most kinds have been converted into a sub- 
 stance which, though greatly altered, still shows its origin 
 very clearly, or into a curious half-crystallized mass, which 
 gives no clue at all, by its appearance, to the history of 
 its formation. 
 
ter % Sbixfy. 
 
 SAND AND SANDSTONE. 
 
 EVERY kind of rock when ground and rubbed to a fine 
 powder becomes sand, and accumulates in heaps or is 
 drifted about on land, or else is carried into the sea by 
 every wind that blows. In addition, however, to loose 
 sands thus driven by the wind, there are many places 
 where we find beds of sand, of great thickness, buried 
 deep within the earth. Such are the dark-red irony sands 
 of Bedfordshire, the paler red sands of Reigate, the white 
 sands of Cornwall and elsewhere (valuable for glass- 
 making), and the black sands of Australia, loaded with 
 tin and gold. These sands are sometimes barren and 
 mischievous, sometimes abounding with metallic wealth, 
 and sometimes used as manure. There are few parts of 
 the world where sands do not appear in some form or 
 other, and a few words about them will be useful and 
 perhaps amusing. 
 
 There is an old Greek story of Midas, who, when he 
 found that his faculty of turning into gold every thing 
 that he touched proved inconvenient, was enabled to part 
 with so dangerous a power by washing in the river Pac- 
 tolus. The fable states that the sands of that river have 
 ever since contained golden particles ; and if the story be 
 true as to the general origin of similar phenomena, it may 
 106 
 
SAND AND SANDSTONE. 107 
 
 be supposed that the representatives of Midas must have 
 heen pretty widely spread over the earth in early times, 
 since most other rivers are provided with similar rich 
 sands. The Rhine is one of these, the Tagus is another; 
 many of the smaller rivers, not only of Europe, but of all 
 parts of the world, might be enumerated as other exam- 
 ples ) and, in point of fact, there are very few streams 
 proceeding from mountain countries in whose beds particles 
 of this precious metal have not been found. Golden 
 sands are thus not rarities ; but the difficulty with most 
 of them is, that it costs at least twenty-five shillings, in 
 labor and machinery, to obtain gold enough to make a 
 sovereign. Such deposits are not, therefore, of necessity 
 sources of wealth, and picking up gold from the gutter 
 may be a far less profitable occupation than tilling the 
 soil and obtaining the precious metal by selling the crops 
 grown from it. 
 
 Still there are parts of the world where sands are well 
 worth washing and separating in order to collect the 
 valuable substances they contain. For a long time Brazil, 
 then Siberia, afterwards California, and more recently 
 Australia and British Columbia, have been very remark- 
 able for their rich yield of various precious metals, of 
 which gold is the most valuable and abundant. In all 
 or almost all these cases, the sand in which the largest 
 quantity has been found has been largely associated with 
 pebbles and gravel. 
 
 Although it is true that all rocks except soft clay yield 
 sand, while even the crystalline varieties of clay itself, 
 and pure alumina in the form of emery, afford a similar 
 powder, we generally understand by sand the powder of 
 
108 THE STONES OF THE BOOK. 
 
 siliceous or calcareous rocks; and the latter, though not 
 very uncommon, are more conveniently regarded in their 
 chemical nature as varieties of limestone. We will, there- 
 fore, limit the expression in this chapter to the fragments 
 of rock that have been chiefly or entirely derived from 
 flint or silica. 
 
 As in the last chapter we spoke of clays as silicates of 
 alumina, considering these deposits as distinct from all 
 others, owing to their composition, so here we propose to 
 take into account another distinct class of materials, form- 
 ing numerous mineral varieties and extensive rocks, but 
 all of which consist chiefly of silica not combined with 
 alumina. Since we are not here treating Geology as if 
 it were a branch of Mineralogy or Chemistry, we have 
 not hesitated to take the substances in this order, because 
 there seemed a certain convenience in describing the clays 
 before the sandstones. We must now, however, go back 
 a little, and explain what is meant by silica and the rela- 
 tion it bears to the element from which it is derived, and 
 the substance (alumina) with which it is so largely 
 associated. 
 
 Silica, like alumina, is derived from a kind of metal, 
 but the metal silicium has never been obtained for any 
 purpose of utility. In this respect silicium cannot be 
 compared with aluminium, and, indeed, its essential pro- 
 perties as a metal are hardly known. On the other hand, 
 the mineral silica is even more abundant than alumina, 
 and is, in fact, almost everywhere present in all soils and 
 rocks. Silica is a combination of the metal silicium with 
 the gas oxygen, just as alumina is a combination of the 
 metal aluminium with the same gas. The combination 
 
SAND AND SANDSTONE. 109 
 
 in both cases produces an earth capable of being crystal- 
 lized ; but in the one case (silica) the crystalline form is 
 very common, in the other (alumina) very rare. Silica 
 is, in fact, as much more common than alumina as alumi- 
 nium is more common and easier obtained than silicium. 
 
 The further combination of silica with alumina we have 
 spoken of in the last chapter, and need not now further 
 allude to it ; for there is quite enough to describe in refer- 
 ence to silica, and the various forms in which it is gene- 
 rally presented on the earth. 
 
 In the first place, there is rock-crystal, in its various 
 forms of Brazil pebble or Cornish diamond, amethyst and 
 cairngorm, quartzite and sandstone ; then there are the 
 agates, chalcedonies, cornelians and cherts, onyxes, blood- 
 stones, and a number of others ; after them the flints and 
 jasper, and lastly the opals, a long list of beautiful 
 minerals, many of which are used and valued as gems or 
 precious stones ; but, as we purpose to devote a special 
 chapter to such objects, we may pass them by for the 
 present. Those we now wish to direct attention to are 
 the sandstones and flints, the humbler members of this 
 large and decorated fraternity. 
 
 Flint is a substance so common in certain localities as 
 to be used for making and mending roads, and occasion- 
 ally for building walls and houses. Elsewhere it is en- 
 tirely absent, and almost entirely unknown ; and as the 
 only real and characteristic flints belong to the chalk, 
 either being found in that rock now or having been washed 
 out of it at some former time, wherever the chalk is at 
 hand the flints may fairly be looked for at no great dis- 
 tance. But they are not always found, for large tracts of 
 
 10 
 
110 THE STONES OF THE BOOK. 
 
 country where chalk exists in abundance have no flints, 
 so that their distribution is still further limited. Most 
 parts of England, however, can show them either as be- 
 longing to the district, or brought there accidentally or 
 by intention : so that we need not describe at any length 
 these dark, half-transparent, brittle stones, always having 
 the same appearance, and showing the same clean wax- 
 like surface when broken, whether we have removed 
 them from the chalk in which they have been long buried, 
 or taken them from the heap of gravel a hundred miles 
 away from the chalk, or picked them up, rounded and 
 shapeless, from the beach at Brighton or some other part 
 of the coast. 
 
 Flints are curious stones enough in their way. Under 
 the microscope they always show some fragment of 
 sponge or the shell of a small animal, or some other 
 proof that they were not always what they are now. 
 Not unfrequently we pick them up after they have been 
 broken in half, and may see that there has been a hollow 
 space in the middle, sometimes partly occupied, some- 
 times empty. Here and there is a flint with part of a 
 shell or a portion of a sea-urchin or sea-egg sticking far 
 into its substance. More frequently there is unmistaka- 
 ble evidence of a sponge, round which the flint seems 
 to have formed, and altogether it is always a puzzle how / 
 it was that the flint and its contents became associated. 
 It seems quite impossible to conceive any other way than 
 by the flint having been at one time soft like a jelly, 
 a substance in which the most delicate and most minute 
 objects might be caught, and where they might be pre- 
 served until the jelly became converted into hard stone. 
 
SAND AND SANDSTONE. Ill 
 
 Flint is one of the purest forms of silica, although, 
 from the dark color it generally has, we see that the 
 transparent rock-crystal is not exactly repeated. Its con- 
 dition is also peculiar, as it is more brittle than other 
 varieties of silica, and is more readily dissolved, and, 
 when mixed with alkali, converted more readily into 
 glass than the rest. One of the great uses of flint now is 
 in the manufacture of glass and porcelain; for although, 
 formerly, myriads were required for our muskets, and 
 they were used with steel for obtaining fire, these uses are 
 now quite superseded. Made red-hot, and in that state 
 thrown into cold water, they very readily break up, and 
 may be pounded into a very fine powder; or, placed in a 
 boiler in high-pressure steam, exposed to the action of 
 potash or soda, they dissolve completely, the result be- 
 coming afterwards soluble even in cold water. But 
 though the state of a jelly may thus be obtained artifi- 
 cially, the flint cannot be reproduced. 
 
 Though chalk is the principal nursery for and nest of 
 flints, many other limestones contain lumps of silica more 
 or less resembling them. Such lumps are more frequently 
 of a dead-white color than half transparent, and are then 
 called chert. They are tougher also than flint, and differ 
 slightly from it in other ways. 
 
 By far the most common form in which silica is 
 found in the earth is that of sandstone. Rocks under 
 this name are found in most countries; and though they 
 differ a good deal from each other in minor points, there 
 are many elements of resemblance. Sandstones are gene- 
 rally made up of particles either of fine sand or very 
 small rolled pebbles, these particles being in some way 
 
112 THE STONES OF THE BOOK. 
 
 or other cemented together. Certainly in some rocks 
 there is no foreign substance cementing them, and they 
 either simply adhere by close contact, which is possible, 
 or are fastened by a siliceous paste. More usually, the 
 grains are cemented by something like mortar, obtained 
 naturally, or by the action of water containing lime and 
 iron. The ordinary sandstones are of the latter kind, 
 and vary much in appearance, hardness, and compactness. 
 There are many in which the grains are of different sizes ; 
 but when some are so large as to form detached pebbles 
 of the size of a pea or walnut, the whole mass has a 
 different appearance from that of a common sandstone, 
 and is called a conglomerate or pudding-stone. In Hert- 
 fordshire and elsewhere there are large blocks of this 
 kind, in which the pebbles are cemented so strongly that 
 it is easier to break the flint pebble across than to sepa- 
 rate the cement. 
 
 The colors of sandstones vary chiefly according to the 
 quantity of iron and marl they contain. All varieties of 
 yellow and red are met with, and frequently the best and 
 hardest kinds are of a pure white and pale gray. Such 
 are the stones of which Edinburgh is chiefly built, 
 stones which seem to be unchangeable by any amount of 
 exposure. 
 
 In Yorkshire are some admirable beds of sandstone, 
 of very fine grain, which split readily into slabs, and are 
 used for foot-pavement. There are others, equally hard 
 and indestructible, of very coarse grain, and useful for 
 making millstones. In the South of England, at Black- 
 down, is a particular kind of rather coarse-grained stone, 
 valuable for sharpening scythes, and sold for this pur- 
 
SAND AND SANDSTONE. 113 
 
 pose; while in the North of Scotland, and in Wales, are 
 huge masses of the purest and most compact fine-grained 
 stone, almost too compact and massive to be practically 
 available. 
 
 While there is thus a great variety of sandstones, all 
 equally pure and useful for various purposes, the middle 
 of England, and several counties in the west, especially 
 Devonshire, Warwickshire, and Cheshire, abound with a 
 much softer kind, easily cut and very cheap, but soon 
 falling to pieces when exposed to damp air. Near Liver- 
 pool there are large quarries of such stone, and the great 
 salt deposits of Cheshire and Worcestershire are among 
 them. The alternate mud and sand of these deposits has 
 been the cause of some of the most curious and interest- 
 ing discoveries of modern times. 
 
 To understand clearly the nature and value of these 
 discoveries, let the reader watch for a while some gently- 
 shelving beach, where there are moving sands and occa- 
 sional mud. In consequence of the variable height of 
 the tides, which are not only periodically high and low, 
 according to the moon's age, but which are also greatly 
 affected by prevailing winds, there are always large 
 patches on such a beach which the water occasionally but 
 rarely reaches; there are others, reached perhaps every 
 fortnight at spring tides, and the rest covered almost 
 every tide. Rills of fresh water often wash fine mud 
 over such flat sands, leaving the mud on the surface, and 
 filling up hollows with it. Almost the whole surface, 
 whenever it is wetted, will be covered with worm-casts, 
 or scratched with the trail of marine insects and crabs, 
 indented by the footprints of birds and small quadrupeds, 
 10* 
 
114 THE STONES OF THE BOOK. 
 
 or spotted over with little pits made by heavy driving 
 rain. After being wetted, the sun shining on the sur- 
 face will dry and crack it. If in this state the mud is 
 deposited in a thin film over every thing, and another 
 deposit of sand happens to be drifted by the wind so as 
 to cover up and conceal the previous marks, it is quite 
 possible that all of them may be permanently preserved. 
 They are as it were stereotyped, and will remain as long 
 as the sands remain, whether they continue soft or are 
 hardened into stone. Now, precisely what might thus 
 happen at any time has happened in former times ; and 
 we have in some of the stone-quarries near Liverpool, and 
 others in Warwickshire, many beds of stone, of which 
 the surface is marked all over with footprints and other 
 indentations. 
 
 And this is the case not in England only, but in Ger- 
 many, in various parts of North America, and elsewhere, 
 generally in particular kinds of sandstone, adapted to 
 retain the impression. Here are to be found, then, the 
 footprints of scores of animals that lived on the shores 
 of islands or continents at the very distant time when 
 the great series of rocks that now form the dry land in 
 the interior of the country had not even begun to t exist. 
 All such animals, and all like them, have long since 
 ceased to live. The conditions of existence have changed, 
 and the animals have changed with them. 
 
 Examining these curious markings, we are, however, 
 in a condition to judge in some measure of the inhabit- 
 ants of the land and sea at the time they were pro- 
 duced. Among a number of round pits, where rain 
 once fell, are numerous little irregular heaps, thrown up 
 
SAND AND SANDSTONE. 115 
 
 by ancient worms, multitudes of lines such as are made 
 by small crabs working their sidelong way to the water, 
 and not a few broad thick lines, crossing, nearly at 
 right angles, the marks of ancient cracks in the mud 
 and sand. All these are easily seen and understood. 
 But besides them are others less familiar. Triangular 
 footprints, as of birds, are mixed with marks of the step 
 of some small but heavy animal, perhaps an ancient 
 turtle; and here and there are huge clumsy indenta- 
 tions, more like the effect of a large hand than a foot 
 pressing on the sand. These hand-like marks are in 
 sets of two, not four, the corresponding two being not 
 only much smaller, but generally obliterated. It would 
 seem that the animal must have resembled in its propor- 
 tions those living kinds which, like the kangaroo among 
 quadrupeds and the frog among reptiles, have two large 
 hind-feet and two very small fore-feet. But no animal 
 now lives, of either class, capable of producing such a 
 footmark; and, until some bones of the animal could be 
 found, it was hopeless to speculate on its nature. At 
 last, in rocks not far off, and of the same kind, bones and 
 teeth were found, which proved that a reptile had lived 
 whose proportions correspond with those of the frog, but 
 whose dimensions exceed those of the largest kangaroo. 
 Thus have the rough marks left in sand, and filled up 
 with mud, on some ancient seashore, introduced us to 
 the knowledge of an animal so entirely unlike any living 
 creature, that the wildest imagination could not pre- 
 viously have imagined the possibility of its existence. 
 
 Sandstones in which such markings are common, being 
 for the most part alternations of perishable and imperish- 
 
116 THE STONES OF THE BOOK. 
 
 able material, are not very valuable for building pur- 
 poses, though used to some extent, when at hand, on ac- 
 count of their cheapness. Much of the town of Liver- 
 pool is built of them. They are very absorbent of water, 
 holding large quantities in ordinary seasons, though in 
 time of great drought they cannot be depended on. The 
 water they contain, when exhausted by continual pump- 
 ing, is apt to become salt, especially when the place is 
 not distant from the sea. 
 
 Large quantities of common salt, often in crystals, are 
 found in some of the sandstones, and in that case the 
 salt may be got away by mining. There are not many 
 known localities where this kind of salt-mining can be 
 carried on, as it is far more common to find brine springs 
 than solid salt. So large is the quantity of water filter- 
 ing constantly through the earth, and so few the cases 
 where it does not pass through porous rocks, however far 
 they may be from the surface of the ground or from the 
 sea, that it is rare to meet with large and important de- 
 posits of rock-salt. The gypsum, or plaster-stone, which 
 is another accompanying mineral, is much more com- 
 monly found. 
 
 Neither salt nor gypsum is, however, found in those 
 hard compact gray sandstones, free from clay and iron, 
 that are common in Derbyshire, Yorkshire, and else- 
 where, where the sandstone is simple in its composition, 
 and tends apparently to turn into a yet more compact 
 and even crystalline mass. Of such a nature is the 
 beautiful white quartz-rock of the Stiper Stones near 
 Shrewsbury. A large quantity of similar rock exists in 
 Scotland. It is too hard and works too irregularly to be 
 
SAND AND SANDSTONE. 117 
 
 available for any useful purpose, except indeed for road 
 material; and its sharp-cutting edges and want of tough- 
 ness do not well fit it even for that purpose. 
 
 Lumps and even larger deposits of bitumen are found 
 in rock of this kind, but they are of no value generally, 
 owing to the difficulty of obtaining the mineral. Some 
 loose sandstones, however, especially those in the South 
 of France and the Pyrenees, abound so much with pitchy 
 matter that it is found profitable to export them. They 
 form the basis of the asphalte pavement, more used in 
 France than England, and perhaps better adapted to a 
 moderate than excessive amount of wear. Asphalte is, 
 however, a useful and valuable material. 
 
 Sandstones are better fitted for conveying water through 
 the earth, for yielding it in natural springs at a hill-side, 
 or for retaining large stores under ground, than any other 
 rock. But for this purpose the sandstone must be open 
 and porous, and must rest on a bed of stiff clay or hard 
 compact rock. 
 
 Few remains of animals are preserved in rocks of this 
 kind. When the particles of sand have been much rolled 
 about before forming the stone, it is natural that most of 
 the fragments of bone and shell, being softer than the 
 sand, should be ground to fine powder. When a deposit 
 is rapid, the state in which the stones and sand are accu- 
 mulated is unfavorable for the preservation of animal 
 remains. Still, there are some districts where excep- 
 tional causes have acted, and fossils occur. In such 
 cases fragments of vegetation are more common than 
 animal remains, and large quantities of wood, now formed 
 into coal and accumulated as stores of mineral fuel, alter- 
 
118 THE STONES OP THE BOOK. 
 
 nate with sandstones in which are the remains of ancient 
 forests in various states of preservation. Leaves of ferns, 
 trunks of trees, and even sometimes very delicate and 
 destructible parts of plants, have been thus handed down 
 in sand-rocks for our examination. 
 
 In some places gigantic trees, thus buried, have not 
 been destroyed, although, doubtless, they were lost sight 
 of from the earth for scores of thousands of years. 
 Fruits of such trees, as well as the trunks and leaves, 
 remain to speak to their nature, and they point out to us 
 the peculiarities of the forests that supplied the coal 
 which we use and waste without thought of its origin. 
 
 Minerals are not rare in sandstones. The whole large 
 family of those that are strictly varieties and modifica- 
 tions of quartz or rock crystal, and that have some value 
 and interest as gems, we leave to another chapter. 
 Others, incidental and not essential, are present in the 
 crevices and veins that abound in the hardest and most 
 compact varieties of sandstone-rocks. The most precious 
 of all metals, gold, often occupies the little interstices in 
 the half-crystalline quartz that forms reefs or ledges, 
 the local name for veins and bands of quartz in sandstone 
 rock. It is true that most of the gold obtained for com- 
 merce has been hitherto got from the sands already 
 broken off from these ledges, but a very important 
 quantity is now worked from the solid vein, both in Aus- 
 tralia and California. This work is hardly less specula- 
 tive than the ordinary mode of washing sands, and is 
 not more frequently successful. 
 
 Diamonds in India and Brazil, topazes in Australia, 
 and other valuable gems elsewhere, are, in nature, asso- 
 
SAND AND SANDSTONE. 119 
 
 ciated with quartz, and are often found in sands and 
 gravel. Tin is obtained from sands, just in the same 
 way that gold is, and there is a remarkable instance in 
 Australia of both these heavy metals being found together 
 in large quantities, in a peculiar black sand, that was for 
 a long time regarded as without value. 
 
 Under the name of quartz and quartzite, crystalline sand- 
 stones are in some places developed either into projecting 
 veins, penetrating other rocks, and forming picturesque ob- 
 jects jutting into the air, or they occupy important positions 
 in mountain countries, remarkable alike for their pictu- 
 resqueness and absolute barrenness. The Stiper Stones, 
 a singularly striking group of rocks in Shropshire, are 
 not less favorable illustrations of the one condition than 
 are the rocks in some parts of Scotland of the other. 
 Pure white in color, jagged and broken in outline, un- 
 mixed with other mineral, untouched by decay, uncolored 
 by moss or lichen, these singular examples of the useless- 
 ness of those forms of matter that resist change stand 
 out in relief, and tell a lesson of no small importance to 
 human nature. 
 
 It is, indeed, by no means the simple minerals in a 
 crystalline state that are useful and available. For rich 
 soils a mixture of a large number of minerals is essential, 
 and even for a soil to provide any sustenance except for 
 grasses, something more than rock is needed. No doubt, 
 if the quartz is in a fine state of division, and thus acts 
 as a sponge, it will, by retaining a certain quantity of 
 moisture, admit of certain growth; but there are some 
 natural cases of finely honeycombed quartz absolutely 
 barren, proving that without the actual breaking up of 
 
120 THE STONES OF THE BOOK. 
 
 the mineral into the finest grains, so as to allow of capil- 
 lary action, there is no means of supplying what plants 
 require. Water has no effect in decomposing quartz, nor 
 is it affected by any of the ordinary acids. 
 
 While therefore silica, in its combined form, is one of 
 the most useful and important of minerals, and is present 
 in almost every part of every mass of matter upon earth, 
 yet in its pure state it is, though occasionally met with, 
 of comparatively small interest and value. It is then 
 almost a curiosity, or might be so if less common; and, 
 except for its picturesqueness when in a mountain dis- 
 trict, it would be regarded only as a worthless material, 
 interfering with vegetable growth. 
 
GRANITE, GEANITIO ROCKS, AND LAVA. 
 
 THERE are stones of a kind different from any of those 
 we have been describing in the last four chapters. There 
 are superb but intractable granites, whose crystals are of 
 substances not affected by water, of which the adjacent 
 rocks are altered as if by heat, and whose structure is so 
 close and firm that no trace of water-action can be seen. 
 There are black cindery-looking heaps, the results of an 
 outpouring of molten rock that has taken place within 
 the memory of the children who sport about the still hot 
 ashes. There are other equally black columns of stone 
 that are not modern, but that are quite as plainly the re- 
 sults of some great conflagration within the earth. All 
 these are stones that have passed through the fire. These 
 are the materials we have to describe and consider in the 
 present chapter. 
 
 And first for the granites. To understand them we 
 must study them first where they run out in sharp reefs 
 and rocks, apparently detached beyond the extremity of 
 some land, and where they lie in wait for unhappy ships, 
 which too often drift upon them and are wrecked in sight 
 of home. Such granite forms the Scilly Islands and* 
 Bocks beyond Land's End, in Cornwall; it forms the 
 11 121 
 
122 THE STONES OF THE BOOK. 
 
 rocks that render the navigation of the Channel Islands 
 so dangerous ; it recurs at intervals all along the western 
 coast of Europe, chiefly when the land terminates in long 
 promontories. The delight of the artist and lover of the 
 picturesque, it is more dreaded than admired by the sailor 
 and the ship-owner. It is one of the natural guardians 
 of our island home, but, like other guards, it exacts its 
 payment. 
 
 Granite must next be seen and examined in the cliff. 
 Bold, grand, naked, and terrible, the granite cliff reveals 
 the source of the danger arising from the detached rocks 
 of the same material. There are fine specimens in Nor- 
 way and Scotland, almost equally fine in Cornwall and 
 Brittany, and others more accessible and quite as grand 
 and characteristic in the islands of Jersey, Guernsey, and 
 Sark. To every one who has an eye and taste for 
 scenery to every one who can appreciate bold, noble, 
 and picturesque outlines, and loves to see Nature in her 
 wildest moods there are no spots within reach more in- 
 structive and finer than the coasts of these little islands. 
 There the granite may be studied in all varieties of form 
 and color. Black and frowning cliffs, where the intense 
 but soft darkness of hornblende crystals gives a distinct 
 character to the coast, broad lines of white quartz or 
 pink felspar intersecting the mass, other narrower lines 
 of white and pink or gray color crossing these at right 
 angles, these are the ordinary conditions. Often covered 
 with sea-weed near the water-line, and with tufts of grass 
 or trees jutting out from the higher parts, these cliffs ex- 
 hibit a certain amount of vegetation, but this is rarely 
 sufficient to conceal the structure of the rock. Varieties 
 
GRANITE, GRANITIC ROCKS, AND LAVA. 123 
 
 of color are common, but granite, commonly so called. 
 is rather pink than dark-green in its general tint. 
 
 It is not only color that is seen in granite cliffs, and 
 that distinguishes this rock from others. Form is equally 
 remarkable. There is a bold, rugged wildness in the 
 naked rocks and peaks of granite that cannot easily be 
 mistaken. There is also a general want of vegetation, 
 not universal, but affecting most parts of the rock not 
 decomposed or broken by veins. The veins themselves 
 are characteristic in the highest degree. They are as 
 beautiful as they are useful. Some are white, vertical, 
 narrow, and of a zigzag broken shape, like lightning- 
 forks. Some are broad, regular, and monotonous. Some 
 are threads darting into and penetrating the solid rock 
 in the most singular manner. Some are wide fissures of 
 the rock, filled up with crystalline material, not extremely 
 unlike the rock itself. 
 
 There are other forms of granite, broad, large rounded 
 mountains, as well as needles, rising out of perpetual snow 
 and shooting into the sky, far above the clouds that con- 
 ceal the sun from the plains below. The rounded masses 
 are not unfrequently covered with stunted vegetation or 
 with peat-bog. Smooth surfaces of granite often, how- 
 ever, terminate seaward with picturesque cliffs; for 
 granite, as well as the softest chalk and loose sand, can 
 be undermined and eaten away by water, and often pre- 
 sents appearances of strength and permanence which are 
 by no means justified by the event. 
 
 We may study granite under other aspects. The tra- 
 veller crosses the sands of Egypt and the mud-banks of 
 the Nile to look at the great Pyramids and the Templea 
 
124 THE STONES OF THE BOOK. 
 
 of Thebes, the results of labor carried on four thousand 
 years ago, and may there see how far in a dry climate the 
 most delicate sculptures on the surface of quarried stones 
 may be preserved without injury. He may study the 
 same result in the British Museum, where are more such 
 specimens to be seen in a day than in many weeks' travel 
 in Egypt; but he must then lose the impression made 
 upon the mind when all the senses as well as the eye 
 combine to tell the same tale. 
 
 But we need not travel so far to learn how enduring a 
 material granite is under favorable circumstances. We 
 cannot, indeed, afford in England to construct the exte- 
 rior of our buildings of polished granite; but it is not 
 uncommon as an ornamental stone for internal work. 
 Under such conditions it may seem, indeed, imperish- 
 able; but a little examination will show that it is even 
 then subject to a certain corrosion from the air, and one 
 can well understand that when sun and rain and frost 
 combine they effect a change in course of time. 
 
 Still the preservation of this stone in the air in our 
 climate is almost perfect, especially when the surface is 
 not broken by little cracks, into which the rootlets of 
 plants and moisture can enter. In such cases, the surface 
 once covered with lichens, a leathery vegetation which, 
 like a stout pair of boots, is a great preservative from 
 damp and injury, there is little change perceptible from 
 century to century, and we call the rock imperishable. 
 
 To understand how far this apparently imperishable 
 condition differs from the real state of the case on an ex- 
 posed coast, it is only necessary to watch carefully for a 
 short time in such localities as those indicated 'above. 
 
GRANITE, GRANITIC ROCKS, AND LAVA. 125 
 
 Sark, a little island nearly torn to shreds, but still resist- 
 ing the final stroke of fate, is full of illustrations of this 
 kind. Every cliif, every cavern, all the curious natural 
 holes, and the natural causeway that connects the two 
 parts of the island together, help to illustrate this de- 
 struction of granite. 
 
 The construction of granite is peculiar. According to 
 the definition of geologists, it is a mass of crystals bedded 
 in a crystalline mass. The crystals are generally of two 
 kinds, the mass being a third kind of mineral. The ob- 
 long, flesh-colored crystals in common granite are called 
 felspar. The little, bright flaky crystals are mica, and 
 the mass in which they occur, often white or gray, is 
 quartz. Often the flaky crystals are not there, but in 
 their stead are dark-green crystals, so abundant as to 
 color the mass. The granite is then called Syenite. 
 There are many other varieties, and the minerals are very 
 differently arranged in different places. Geologists give 
 different names to each principal variety, but it is not 
 necessary to trouble ourselves with these names. 
 
 The veins of the granite mass have already been 
 alluded to. They are often crevices of some width, more 
 or less open, and full of beautiful crystals, partly of the 
 minerals of which the granite is made up, partly of 
 foreign minerals valuable as yielding metals. Silver, 
 copper, lead, and a multitude of other less common 
 metals are found, either as metals, or as stones yielding 
 metals, in these crevices. They are then called mineral 
 veins, and are the object of search to the miner. They 
 are by no means confined to granite, but are so frequent 
 10* 
 
126 THE STONES OF THE BOOK. 
 
 in that rock (though not always valuable) as to be cha- 
 racteristic. 
 
 Granite peeps out in almost every part of the earth, 
 when for some reason the great underlying mass, often 
 called the skeleton of the earth, is made to show itself at 
 the surface. Thus it forms the extremities of land as on 
 the west coast of Europe and in the European islands. 
 In the Alps and other great and lofty mountain-chains it 
 forms either the central or some important parallel range. 
 It is seen where the oldest and last of the limestones, 
 sandstones, and clays is past, and where their changed 
 conditions have also been passed by. It is thus a rock 
 belonging to the earth's interior, and all that is known 
 about it tends to prove that it has been formed at great 
 depth, under great pressure, and even where there was 
 very great heat. Not that it bears marks generally of 
 having been a molten rock in the ordinary sense of the 
 word. It is not like lava, which we shall speak of pre- 
 sently. It has none of the slag-like appearance or struc- 
 ture of substances melted near the air. In its most in- 
 timate substance among the very crystals of which it is 
 composed, it contains water clearly discoverable by the 
 aid of the microscope, and recognized even sometimes by 
 the naked eye. 
 
 Such is granite. Porphyry is another name for it. 
 There are porphyries of various kinds, and granite is one 
 of them. They are all crystals in a crystalline mass. 
 All are hard; some are among the hardest substances 
 known, so tough that they can scarcely be worked into 
 shape with any tool. In the great exhibitions'of won- 
 derful works of art and manufacture we see vases and 
 
GRANITE, GRANITIC ROCKS, AND LAVA. 127 
 
 ornaments of various kinds, chiefly from Russia, con- 
 structed of such material, and they mark the employ- 
 ment of enormous labor, with the aid of all that modern 
 ingenuity can supply in the way of machinery. Even 
 under these circumstances years are required for their 
 completion. In other museums where are collected the 
 curious implements of our forefathers of those human 
 beings who dwelt in these and other lands, long before 
 the historic period, before the Romans, before the Kelts, 
 before all those peoples who have had definite names 
 assigned to them we may find from time to time, among 
 the axes and spear-heads and stones of curious shape 
 and doubtful use, specimens of such hard porphyries, or 
 of stones equally hard, and not known as rocks nearer 
 than Asia, worked and smoothed and even polished, in 
 spite of their hardness and of all the difficulties involved. 
 These, it is true, are facts that only belong to Geology in 
 a limited sense, but they deserve mention when speaking 
 of the porphyries, cf which granite is an example. 
 
 Occupying a very different position in the earth, 
 often resting upon limestones, or sandstones, or clays, 
 unevenly and irregularly deposited, and manifestly in- 
 trusive in every sense, there is another class of rocks 
 that we must consider in this chapter. These are known 
 as lava and basalt, lava, if found to have been erupted 
 recently in a melted state; basalt, if forming part of the 
 earth's crust in places where there has been no volcanic 
 disturbance within human experience. 
 
 Lava is a very characteristic mineral. It is a kind of 
 glass, produced by the melting of all the common minerals 
 and rocks near the earth's surface, assisted by those alka- 
 
128 THE STONES OP THE BOOK. 
 
 line earths which act as fluxes, the whole having been 
 exposed to a great heat at a moderate depth in the earth, 
 and brought to the surface by one of those volcanic dis- 
 turbances connected with earthquakes, which from time 
 to time produce such destruction in particular localities. 
 Etna, Vesuvius, and Hecla, in Europe, and a multitude 
 of similar mountains in Asia, South America, and else- 
 where, are familiar examples. In all these, after the earth- 
 quake, and the eruption of gas and steam, a flood of lava 
 generally follows, -and this lower part, cooling slowly 
 under some pressure, becomes a compact stone, while the 
 upper part, mixed with air, and cooling rapidly, is spongy, 
 and converted into a kind of slag. The magnitude and 
 extent of these floods of melted rock will be alluded to in 
 another chapter. 
 
 Basalt is the lava that has been erupted from vol- 
 canoes, probably at the bottom of the sea. It is often 
 spread horizontally in sheets over large tracks, and not 
 unfrequently there are many successive sheets overlying 
 each other in the same district. Many varieties of this 
 rock occur : they are generally of various shades of gray 
 and green, passing into black. Some are full of crystals, 
 others compact and fine-grained. The most usual cha- 
 racter, however, is that they are grouped in columns so 
 regular, and on so large a scale, as to present all kinds 
 of grotesque appearances. 
 
 Among the best known of these groups of basaltic 
 columns may be mentioned the Giants' Causeway, on the 
 coast of Antrim, in Ireland; Fingal's Cave, in the Isle 
 of StafFa, nearly opposite; some very fine specimens on 
 the Rhine, near Bonn, and others a little higher up the 
 
GRANITE, GRANITIC ROCKS, AND LAVA. 129 
 
 same river; and L some in the Eifel. Few things are 
 more striking in their way than these basaltic columns 
 when shown in a cliff or cavern. The uniformity, which 
 seems almost complete when one column is compared 
 with that adjoining, is not continued over a large area, 
 but amply fills the space which the eye can reach. 
 Rising straight or curved from the ground, there is an 
 appearance of myriads of six-sided columns touching each 
 other, and only made manifest by weathering or quarry- 
 ing. Generally of a black color, the effect is gloomy 
 and grand. If the columns run out towards the sea, they 
 are of course broken off and form a causeway, or are 
 partly eaten out and leave caverns. If in a quarry, they 
 are like the pipes of a gigantic organ. For miles, in a 
 cultivated country, their existence is shown by milestones, 
 gateposts, and all other vertical stone supports, con- 
 structed of ' these convenient and natural columns. Often 
 they are carried to great distances for these purposes, 
 and for road-material, as they do not readily injure by 
 exposure, and are among the toughest substances known. 
 All varieties of lava and basalt are not indeed alike in 
 this respect, but most of the rocks of the kind described 
 in this chapter are both hard and tough. 
 
 Returning to the granites, we must now notice a rock 
 extremely abundant in Scotland and elsewhere, often seen 
 on the flanks of granite mountains, and presenting almost 
 the same mineral group as granite itself, but splitting 
 readily into slabs, more or less thin and regular in differ- 
 ent places. This mechanical arrangement is not met with 
 in the granite, and the rock that exhibits them is called 
 gneiss. It is one of a class of rocks, some of which are 
 
130 THE STONES OP THE BOOK. 
 
 schists. The young geologist may easily be puzzled in 
 endeavoring to draw a line of demarcation between the 
 granites and these other rocks, as such line does not 
 always exist, and, when it does, is not well defined. 
 Gneiss and granite may be looked on as quite sufficiently 
 similar to be classed together as minerals, though distinct 
 in their mechanical arrangement. 
 
 Rotten granite is a condition of the rock so different 
 from that with which most people are familiar, that it 
 may seem almost an absurdity. Nevertheless, there are 
 very extensive tracts where the granite falls so easily to 
 powder, on exposure to the air, as to affect the scenery. 
 There is a curious example of this in Bavaria, near the 
 mountains that separate Bavaria from Bohemia. It is a 
 considerable hill, where the granite is eaten away at the 
 surface j and the following description of it is accurate and 
 picturesque. The hill is called the Louisenberg : 
 
 " The road to the Louisenberg lies along the slopes of 
 a hill, Copiously strewn with loose masses of granite, 
 increasing in size and quantity as you advance, until at 
 length the hill seems to consist of nothing else but dis- 
 jointed fragments, piled in heaps one over another. Such 
 a vast pyramid of loose rock might have furnished the 
 Titans with ammunition when storming Jupiter in 
 Olympus. If you begin at the bottom of the hill, and 
 climb to the top, or compass it round, you will find no- 
 thing but rocks in pieces, tumbled about in all directions; 
 and the result is a kind of labyrinth, in which one may 
 wander about for hours, sometimes creeping, for many 
 hours together, through caves, dark or barely admitting 
 a few gleams of light between the interstices of the huge 
 
GRANITE, GRANITIC ROCKS, AND LAVA. 131 
 
 superincumbent masses which form" their roof, at others 
 threading narrow clefts, or scrambling over projecting 
 masses to the summit of the hill, which is itself a de- 
 tached block/' Murray's Handbook for Southern Ger- 
 many, 3d ed. p. 88. 
 
 Many other remarkable points of scenery are produced 
 in the same way, but chiefly in sea-elifFs and by the coast 
 on bleak moors. It is not often that the decomposed 
 rock is so favorable to vegetable growth as in the case 
 above described. The number of trees growing on the 
 hill give, indeed, the appearance of a wood, and " the 
 peculiar luxuriance of the dark-green moss, covering the 
 rocky walls with a continuous tapestry," imparts an air 
 of soft beauty almost peculiar to the Louisenberg. The 
 whole neighborhood consists of sand and gravel, d 
 from decomposed granite. 
 
p*Mg| 
 
THE GREAT STONE BOOK 
 PART III. 
 
 12 
 
IN THE BRICK-FIELD AND THE GRAVEL-PIT. 
 
 WE have now seen the way in which a river removes 
 and deposits stones and mud, the effect of the tide and 
 the storm-waves of the sea in destroying a cliff and pro- 
 ducing a shoal, and the mode in which a glacier removes 
 and an iceberg distributes the accumulated fragments of 
 the mountain-side on which it is formed. We have also 
 seen what are the clays and limestones and sandstones 
 with which the water and the ice have generally to deal; 
 how these are, for the most part, water-formed and water- 
 worn, though since hardened, and often much changed. 
 But there is a connecting link between these relics of a 
 time long past and the mud and sand left by the river in 
 its recent course, or now moved by the sea ; and this 
 link we must next endeavor to make out. It is a very 
 interesting and important one. It is the most direct, 
 and perhaps the most instructive, of all the early lessons 
 in Geology. It introduces the subject of Geology, and 
 all its peculiarities and characteristics, as distinguished 
 from what is called Physical Geography, a science which 
 relates only to the present. 
 
 There are many ways of making this step in our 
 science, and each place will, generally speaking, have 
 
 135 
 
136 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 in its neighborhood some particular locality better for 
 it than another. In many parts of the country, the only 
 means at hand will be the examination of the spots where, 
 by some road-cutting or the passage of a small stream, 
 the common vegetable soil has been removed and its 
 gradual change laid bare. This change is generally as 
 follows : first into a coarser soil, then into a mass not 
 worth calling soil, and then, at last, into some uniform 
 mineral mass that we may call a rock. Whatever this 
 rock may be, it is sure to serve our purpose, and mark 
 the difference between the soil in which plants are nou- 
 rished and the great body of the earth. 
 
 In many parts of England, however, and, indeed, in 
 most parts of Northern Europe, there is, near the sur- 
 face, a considerable heap of rounded stones and sand, 
 that we call gravel, and often a good deal of stiff 7 clay, 
 working into a paste with water, and very tena- 
 cious. Of such clay bricks are often made, and thus it 
 is known as brick-clay. The mixture of rounded stones 
 and sand, called gravel, is often very thick. It is found 
 both in hollows and on hill-tops. It is made up of stones 
 of all kinds, many of them quite unlike those of the rocks 
 at hand. These are mixed irregularly, and the whole 
 mass seems as if placed on the surface without any order, 
 the clays in one place and the stones in another. Occa- 
 sionally there are thin beds of white sand, but these are 
 rare. Sometimes there are bones of animals mixed with 
 the stones. These are not always broken, and were ap- 
 parently brought or left with the heap of stones in which 
 they are found. It is evident that some reason must 
 exist for the occurrence of all these heaps where we find 
 
IN THE BRICK-FIELD AND THE GRAVEL-PIT. 137 
 
 them ; and people's ideas were first, and for a long while, 
 directed to the probability of their being proofs of a 
 great deluge that once swept the human race from the 
 earth. A closer examination proves that this is not the 
 case ] but these heaps remain, and to them we now re- 
 quest the young geologist's attention. 
 
 SECTION SHOWING THE HEAD OP EARTH, THE SAND, AND THE CLAYS IN A 
 BRICK-PIT. 
 
 a. The head of soil. b. Sands above the clay. c. The clay. 
 
 d. The rock below the clay (not conformable). 
 
 To understand more clearly the facts of the case, let 
 the reader, if possible, repair to a brick-field or gravel-pit, 
 and examine the cutting made to get at the clay or 
 gravel. Near the top, but below the vegetable soil, there 
 is probably a quantity of earth which the workmen call 
 a head, consisting of rubbish; and through this, though 
 not real soil, many of the roots of trees and plants have 
 penetrated. The rubbish is not everywhere of the same 
 kind or of equal thickness: some parts of it probably 
 contain good soil mixed with it, while other parts, close 
 by, only show a thin coating of a few inches. Below the 
 good soil will, perhaps, be found poor, hungry, worthless 
 clays, broken stones, and sands, until at last one particu- 
 lar bed of clay is reached that is fit for making into 
 bricks. 
 
 12* 
 
138 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 Just so with the gravel-pit. The gravel is in streaks 
 or beds below the vegetable soil; and of these beds one 
 lies above another, not very regularly, but still with some 
 approach to order. Particular beds show all the stones 
 well rounded, and nearly of the same size; while other 
 beds or parcels of the gravel are more sandy, or made up 
 of stones less completely sorted. In all cases, wherever 
 you look at any cuttings such as are seen in gravel-pits, 
 you will find that there is a good deal of order in the 
 way the different materials are arranged, although they 
 are by no means built up with perfect uniformity. 
 
 Now, how do you suppose the clays, and sands, and 
 pebbles were placed where you find them ? A little care- 
 ful search will generally discover, buried in the earth at 
 the top, some snail-shells, and bones of horses, cows, 
 dogs, rats, or sheep, hidden among the roots and buried 
 vegetation. You will probably find none of these, nor 
 any thing like them, below, but, in their place, some of 
 the common fresh-water shells, such as belong to the 
 inhabitants of adjacent rivers or ponds, mixed with the 
 clay and sand ; or perhaps there may be a few bones of 
 animals not common in the neighborhood, or some shells 
 which have certainly come from the sea. These latter 
 are often heaped in considerable numbers, and must have 
 come in originally as part of the gravel or clay deposit.^ 
 
 With these marine shells, which are familiar enough 
 on the nearest sea-shore, but seem strangely placed in the 
 brick-pit, and still more strangely mixed up with fine 
 sand and mud between two beds of gravel or flint-pebbles, 
 there is generally no mixture of bones of land-animals, 
 and no plants, although these are common enough else- 
 
IN THE BRICK-FIELD AND THE GRAVEL-PIT. 139 
 
 where, and equally well preserved; neither are there 
 pond-shells. When, in comparatively rare instances, 
 bones are found, they are worn and rolled, as if by water, 
 but they are not the bones of domesticated animals. 
 
 Knowing, as we do, what water can effect in the way 
 of collecting, removing, and arranging such things, we 
 cannot help feeling that all the clay, and mud, and sand, 
 and pebbles must have been placed where they are by 
 water. True, there is no water now near them, true, 
 the sea is not only far off, but at a lower level; all this 
 may make it very difficult to understand how the matter 
 was arranged, but it need not alter the conclusion that as 
 water now does precisely similar things in a way we see and 
 know, so water must have done this thing. We can only 
 believe that the accumulation, whatever it was and when- 
 ever it took place, occurred under water which has since 
 departed from the surface. 
 
 All beds of gravel and sand mixed with mud, whether 
 containing shells and bones or not, must, doubtless, have 
 been brought together under water; and most parts of 
 our island are covered with such beds here and there. 
 All or nearly all the plains of Europe are of the same 
 kind, and were certainly under water when their present 
 coating of gravel, clay, &c. was brought together. 
 "What!" it may be exclaimed; "has all England, and 
 almost all Europe, been under water so recently?" 
 There cannot be a doubt that such is the case. 
 
 In the sacred history, with which all are acquainted, 
 there is an account of a great deluge which covered the 
 land with water, destroying almost all the living inha- 
 bitants. 
 
140 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 The precise meaning of the sacred history in respect 
 to that deluge, or its exact date, are subjects that we need 
 not here discuss; but one thing in regard to it is certain, 
 namely, that a large part, perhaps the whole, of the 
 earth's surface has been under water since man was 
 among its inhabitants; and it is possible that many 
 similar and partial deluges have taken place at different 
 times during the earth's history. 
 
 A deluge, however, does by no means assume that 
 water was miraculously added to the quantity previously 
 existing and forming part of the earth's surface. It 
 means, no doubt, that the relative levels of land and 
 water were changed, and that what had once been land 
 became buried under water. It may also mean that, in 
 places long covered by the sea, the sea-bottom was lifted 
 up and became dry land. All land, probably, has been 
 in turn the bottom of a sea, and while under water it bo- 
 came covered with mud and marine animals. The bottom 
 or bed of the sea has often been converted into land, and 
 the land has become buried and lost sight of. The new 
 lands were of different shape and had a very different 
 climate from the old which had previously existed in the 
 same neighborhood. 
 
 But neither is it necessary to suppose that every 
 deluge, or great rush of water, was accompanied by a 
 violent breaking up of the land. This may sometimes 
 have been the case; and earthquakes have often produced 
 wonderful and very mischievous commotions, in different 
 parts of the world, tending to this result. But the 
 change of level may sometimes have been very gradual, 
 and need not have been attended by a breaking up of the 
 
IN THE BRICK-FIELD AND THE GRAVEL-PIT. 141 
 
 surface. There may, in other words, be destructive and 
 change-producing causes that take even thousands of 
 years to complete; and during such slow and unnoticed 
 revolutions the clays of our brick-field and the stones of 
 our gravel-pit may have been placed in their present 
 position. 
 
 When rapid changes such as those of earthquakes happen 
 on the earth, the effect, although it excites more atten- 
 tion, is not so great as that brought about by the slow 
 alterations which many hundred years are needed* to com- 
 plete. It has taken a long time for frosts and ice to 
 bring together such a heap as is to be found in any of 
 the principal gravel-beds near London, a time far longer 
 than could be supposed; longer, indeed, than can be cal- 
 culated; longer, even, than we have been accustomed to 
 think the world has existed. What, then, must have 
 been the time required to build up the world, if there 
 are many of these gravel-beds heaped one upon another, 
 all of different ages, the lowest being the oldest ? This 
 is one of the difficult questions of Geology, and one that 
 can never be exactly answered. All we can do is to ex- 
 amine and compare facts, and judge by comparison when 
 we have fully considered the facts. 
 
 But let us look more closely at the beds of gravel, 
 separated from each other sometimes by sand, sometimes 
 by gravel of a different kind. In a thickness of twenty 
 or thirty feet there will generally be a good many varie- 
 ties, and we shall see any particular bed that is worked 
 vary here and there. Pick out a few of the pebbles, and 
 look at them. 
 
 Here is a well-rounded black pebble, about the size of 
 
142 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 an egg, very smooth and almost polished, but the surface 
 is scratched all over with fine marks, showing clearly how 
 the stone became round and smooth. Next to it is a 
 broken fragment, the edges rounded and worn and a 
 clean broken face presented. Both are flints, and both 
 exactly resemble other flints, whether in the gravel, on 
 the sea-beach, or in the chalk-cliff. It takes a long while 
 to roll so hard a stone as a flint into the shape of an egg 
 and carry it with others into a great heap far away from 
 the sea. It takes considerable force to break a flint 
 pebble in half. 
 
 We have next to see what a flint is, and where it comes 
 from, in order to know what is the relation of this gravel- 
 pit with the various rocks in its neighborhood. Let us 
 break it in half with a hammer and try if any thing is to 
 be learnt by looking at the inside. It is not unlikely 
 that when broken there will be a small empty space in 
 the middle, partly occupied with little crystals. Perhaps 
 there is no empty space, but a distinct shape resembling 
 gome more or less known part of an animal, as if the 
 flint had once been pasty and had entangled a sponge, a 
 shell, or sea-anemone, just as in jellies the cook will en- 
 close fresh strawberries or cherries, or as flies are caught 
 in resin. At any rate, we are almost sure to find, if we 
 look closely enough, using that wonderful contrivance 
 the microscope, that little white or gray spots in the 
 clear flint once belonged either to sponges, or to shells, 
 or to some other creature formerly inhabiting the sea. 
 
 The flints generally found in gravel are very different 
 from most other stones we meet with. The former all 
 seem similar, and, though mixed with other very different 
 
IN THE BRICK-FIELD AND THE GRAVEL-PIT. 143 
 
 stones, they, no doubt, have all come from the chalk. 
 The only places where such material is at all abundant 
 are the various chalk-hills, many of them at consider- 
 able distance. Beds of flint, unbroken and undisturbed, 
 often alternate with the beds of chalk, and it is supposed 
 that the pebbles once formed part of other chalk-hills 
 now washed away. 
 
 Must we, then, believe that all our gravel and brick- 
 clay consists of the remains of older deposits broken up? 
 Such is, indeed, the geological conclusion; and thus it is 
 that these pebbles, so useful and so common, carry us 
 back to rocks of much older date than themselves and 
 serve as connecting links not only between the sea-beach 
 and the heaps of boulders far removed from the sea, but 
 also between the gravel-bed and the chalk-cliff. 
 
 There was a time when our gravel-beds did not exist 
 as gravel, but when the raw material, the unrounded 
 stones, were buried in the chalk-hills, which were then 
 entirely under water. As gravel covers not only a large 
 proportion of England, but also much of Northern 
 Europe, there must have been a larger quantity of chalk 
 then than there is now, and probably it extended much 
 more widely and to places where we can at present find no 
 appearance of it. By the washing of the sea the chalk 
 was worn away in many places and the flints separated 
 from the fine chalk mud. Being hard stones, they were 
 then rolled about till most of them were rounded, and 
 they were collected in heaps, those of the same size keep- 
 ing together, and the mud and sand forming bands be- 
 tween them. 
 
 Looking at the flints in gravel merely as stones, they 
 
144 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 thus mark a great change and the lapse of a long time ; 
 but when we find shells sticking in them, or sponge-like 
 bodies buried in them, like flies in amber, they offer other 
 subjects for thought. Of all things, flint is one of the 
 most solid and hardest. If people build walls with it, or 
 expose it in other ways to weather, it never seems to 
 alter or decay. It is true that, if put in a hot fire, it 
 gets very brittle, but still it never melts; and no process 
 of nature that we know of could soften it into a paste, so 
 that one could stick a shell upon it, or make it to enclose 
 the delicate little sponges so often seen within it. 
 
 But though neither fire nor water will soften flint un- 
 assisted, there are means not only of making it soft, but 
 even of dissolving it in water. When put in open iron 
 cages, and held for some time in a steam-boiler, with 
 caustic potash or soda, such as is obtained plentifully 
 from chemical works, it becomes at last completely 
 sucked up by the water, like a lump of sugar, and the 
 water itself looks like a thick syrup, in which you might 
 easily put the most delicate little coral without injury. 
 Exposed to the air, this syrup thickens and at last 
 hardens, but it does not turn into flint again quite so 
 easily. It long remains white, and is greatly affected by 
 damp air. Still, we see how a soft condition of flint may 
 be produced; and some day we may discover the way in 
 which, the potash and soda being quite got rid of, a flint 
 can really be re-made. 
 
 But there are no steam-boilers and stores of caustic 
 potash and soda at the bottom of the sea, where chalk 
 was made. This is merely a way in which shells and 
 sea-weed might now be buried, as it shows that the 
 
IN THE BRICK-FIELD AND THE GRAVEL-PIT. 145 
 
 change of hardness is not quite impossible. Nature's 
 way was rather different, and perhaps much slower, but 
 not less complete in the end. 
 
 We return now to the completely-formed gravel. 
 Mixed with the pebbles, and above or below them, are 
 found sometimes bones, and occasionally, though not often, 
 pieces of flint, looking as if they had been split and chipped 
 into their shape by savages. No bones of men have been 
 found, but there are remains of such animals as horses, 
 horned cattle, wolves, foxes, and bears, mixed up with the 
 leg-bones, backbones, and teeth of the elephant, the rhi- 
 noceros, and the hippopotamus. 
 
 A strange and unexpected discovery was this mixture of 
 flint weapons, sculptured by man, with the bones of do- 
 mestic animals and the bones of such animals as the ele- 
 phant and hippopotamus. One's first idea is, that either 
 the one or the other set has been introduced accidentally 
 at a different period, or that all have been removed toge- 
 ther by some recent torrent, the older being mixed with 
 the newer. We feel inclined to look upon the deluge 
 of Noah as a probable cause of such a mixture, and to 
 speculate on the races of men that lived before the 
 Flood as having indeed covered the whole earth, and 
 been all inhabitants of a world whose climates were little 
 varied, and in which the elephant and the lion of the 
 tropics, the horse, ox, deer, dog, and beaver of the tem- 
 perate regions, and the great polar bear and seals of 
 the icy seas, could live together in the climate of Eng- 
 land. 
 
 But a little further knowledge and examination into 
 what Geology teaches will show that this way of ex- 
 
 13 
 
146 PLACEMENT AND DISPLACEMENT OP STONES. 
 
 plaining appearances is not the right one. The ele- 
 phants, and other large animals of that family (the 
 rhinoceros and hippopotamus), were not exactly like 
 those living now in India and Africa. The elephant 
 was covered with thick and long hair, the rhinoceros 
 and hippopotamus were differently proportioned from 
 those we are now familiar with. Their bones, also, are 
 in far too perfect a state to allow us to suppose that they 
 have been rolled about on the sea-shore ; and the harder 
 bones and teeth are too abundant to allow us to imagine 
 for a moment that they have been drifted a long dis- 
 tance, from places where the climate more resembles 
 that of their present habitations. 
 
 Some sixty years ago, a complete elephant was found 
 buried in frozen .gravel in Siberia, and similar frozen 
 cliffs elsewhere have been found to contain complete 
 carcases of other large animals. The flesh on these 
 carcases was preserved as we preserve meat in ice-chests, 
 but still more perfectly and for a longer time. When 
 thawed, so that foxes and dogs could get at it, these 
 animals soon showed that they had not before had such 
 a chance, by devouring the flesh as rapidly as possible. 
 These large quadrupeds must have lived in the neighbor- 
 hood, and had been unexpectedly caught up in the water, 
 perhaps carried to a distance after being drowned, 
 till they entered within the region of perpetual frost, 
 where they were built up as part of a frozen mass of water, 
 mud, sand, stones, and carcases, to remain unchanged 
 for centuries, owing to the preservative power of ice. 
 
 Frozen water has, no doubt, had much to do with the 
 distribution of gravel, as well as with the burying and 
 
IN THE BRICK-FIELD AND THE GRAVEL-PIT. 147 
 
 preserving these curious remains of a former world. In 
 the upper valleys of the Alps, and in other mountain - 
 districts, under favorable circumstances, where water that 
 would otherwise have fallen on the plains in rain is 
 deposited as snow, and the snow, instead of melting, 
 hardens into ice, and then, by its weight, slides gently 
 down into the lower valleys, are formed the glaciers, 
 already described in a former chapter. These rivers of 
 ice continue to descend, until they become converted 
 into rivers of water in temperate climates ; but far away 
 on the vast and little-visited shores of the polar seas, 
 every nook and mountain-gorge is loaded with such 
 masses, which fill the valleys and project far into the 
 sea, and, when large enough, break away and float off in 
 the form of ice-islands. Owing to currents in the ocean 
 moving ^always from the poles towards the equator, the 
 ice is drifted in very large quantities, coming down 
 towards the south from the north pole and towards the 
 north from the south pole, until the whole of the ice 
 is melted. But so long as the ice is attached to the 
 glacier and the land, it is constantly receiving fresh 
 supplies of broken rock, split off at every change of 
 weather from the mountain-side, so that each floating 
 island, or iceberg, becomes loaded with thousands of tons 
 of mud and stones, which of course reach the bottom of 
 the sea when the ice melts. Thus there must be a con- 
 stant accumulation on the bottom of the ocean of such 
 stones brought from a great distance; and, as they are 
 rolled over and over one another on shores and shallow 
 places, they become at last converted into fine mud and 
 rounded pebbles. 
 
148 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 But there are some other things to be considered, for 
 it must not be concluded that all the ice continues float- 
 ing till it is melted. Owing to the fact a very curious 
 and important one that ice is rather lighter than water, 
 the ice floats at or near the surface, with only a small 
 part visible in proportion to the whole mass. This pro- 
 portion is smaller as the weight of the load, the freight 
 of stones and mud it conveys, is greater. If the ice is 
 eighty or ninety feet high above the water and this is 
 no uncommon height it may be very safely assumed 
 that it is six or eight hundred feet or more in depth, 
 and correspondingly larger ; and if it passes over a sea 
 not so deep as this, the whole mass will be stranded and 
 prevented from further advance. When this happens, 
 the momentum or impetus possessed by so large a mass 
 of matter in motion cannot be suddenly stopped ; and 
 the ice-island, like a ship when it takes the ground, will 
 be partly lifted over the mud or stone-bank on which it 
 has struck, and in this operation will grind and be 
 ground with extreme energy, and remain firmly buried 
 in its place till it becomes sufficiently lightened of its load 
 by melting above to float oif again. Wonderful effects 
 of this great, force of grinding are sometimes seen on 
 rocks that have been exposed to it. 
 
 Besides the ice and the load of stones it conveys, 
 there are other important means in nature by which 
 broken rocks are turned into pebbles more or less 
 rounded, and into mud more or less fine. Every coast 
 is inevitably exposed to the action of running water, 
 and materials are removed with a rapidity proportioned 
 to the softness of the rock and the violence of the waves. 
 
IN THE BRICK-FIELD AND THE GRAVEL-PIT. 149 
 
 Cliffs are thus torn away and destroyed, and every bed of 
 shingle and sand is rolled over and over by the cease- 
 less rise and fall of the tide, and disturbed by the occa- 
 sional dash of the tempest, till it is in time ground into 
 mud. There is, however, constantly afresh supply of raw 
 material, consisting of fragments of worn and fallen rock 
 and after the first angles of the broken stones have been 
 knocked away, pebbles are soon formed. The formation 
 of beds of gravel and clay is probably going on con- 
 stantly in many seas, and ample provision is being made 
 for future lands in this respect. 
 
 But if pebble-beds and thick clay were heaped toge- 
 ther under water, as all the facts concerning them seem 
 to show, it cannot be wondered at that they contain 
 now and then the shells and bones of the inhabitants of 
 the water and adjacent land, nor, on the other hand, 
 need we be surprised if in most cases these delicate 
 organizations are bruised and injured, and a large pro- 
 portion of them totally destroyed, by the rude conflict 
 of the waves, and the rubbing and grinding they have 
 undergone. Where simply drifted without being much 
 rolled, the fossils may remain; but where drifted and 
 long exposed, we may be sure there will be little indica- 
 tion of life. 
 
 When we consider the wide extent of country that is 
 covered with thick beds of brick-clay, and the innume- 
 rable patches of gravel, some of them not small, dis- 
 tributed over the surface even of our own country, we 
 shall see how wide-spread must have been the causes at 
 work. And when we look, too, at the thickness of fine 
 soil often lying undisturbed over the clay and gravel, 
 
 13* 
 
150 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 and the long time that things must have remained nearly 
 as they now are to account for this accumulation of soil 
 and growth of vegetation, it will be evident that the 
 changes by which our island was brought into its pre- 
 sent position and height above the water were no affairs 
 of yesterday, but must date back far, very far beyond 
 our records. In the beds of gravel below the vegetable 
 soil, and among the remains of large elephants and rhi- 
 noceroses, are buried those curious flint weapons that 
 have been already alluded to, now generally admitted to 
 be of human manufacture. "When and how could these 
 our ancestors have existed, and what must have been the 
 state of our island when they were its only inhabitants ? 
 These, again, are among the queries to which we cannot 
 expect to receive satisfactory replies, and it is better not 
 to puzzle or confuse ourselves at present by discussing 
 them. 
 
IN THE QUARRY AND THE MINE. 
 
 EXCEPT to those who, however, are numbered by 
 millions buried for the greater part of their lives in 
 the streets of large towns, there are few who have not 
 access to some kind of quarry. Even the townsman, 
 however, can generally find within moderate distance a 
 good bare face of railway-cutting, if he cannot reach a 
 spot where stone is being removed for building purposes 
 or road-making. To the young geologist every quarry, 
 of whatever material, is full of instruction of many 
 kinds. 
 
 All kinds of stone are quarried. From the hardest 
 and toughest granite, or from the tough or soft sand- 
 stones and grits, to the merest sand in a pit, from fine 
 white statuary marble, through all varieties of limestone, 
 to chalk, from magnificent sheets of slate to poor shale, 
 there are places to be found where it is worth while to 
 pare away the vegetable soil and subsoil, to cut the hard 
 rock into a series of steps such as giants might climb, to 
 split away the stone with blasts of gunpowder, to pile 
 the waste stone or let it fall down some steep slope to the 
 sea, and thus to exhibit the skeleton of the earth for con- 
 venient observation and experiment. 
 
 Very large and magnificent are some of these illustra- 
 
 151 
 
152 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 tions of Nature, and often the contents of such large 
 quarries are of absorbing interest. Others are much 
 smaller, and in many cases the whole interest is concen- 
 trated in the present works, the surface soon becoming 
 weathered by the action of damp air, rain, and frost. 
 
 The points of chief interest in quarries are these : 
 (1.) They show us the mineral crust of the earth, sands 
 converted into sandstones, muds into limestone or slate, 
 materials of which we know very little into granite. (2.) 
 They show us the peculiar changes in position by which 
 these materials, once at the bottom of deep water, have 
 been placed in the order we now find them ; or, in other 
 words, they illustrate the nature of the forces that have 
 lifted the earth's crust. (3.) They show us very often, 
 in a perfectly distinct manner, that the original accumu- 
 lation, now stone, was a succession of shelly beds, or an 
 alternation of shelly and impalpable mud, or a heap of 
 sand followed by mud with shells. (4.) They tell us 
 whether the original material was deposited in water, 
 and whether the water was deep or shallow. (5.) They 
 enable us to measure, in a rough and approximate way, 
 the relative time required for the original deposit. (6.) 
 They inform us of the changes that have taken place 
 in the arrangements of the animal and vegetable world 
 since the present hard rock was deposited as soft mud. 
 
 In the present chapter we will only consider a few of 
 these numerous and valuable sources of information. It 
 is in quarries that we can most easily learn how the 
 stones in the book are built into their places; how they 
 have passed from one state to another; how they are 
 connected with remains indicating life; how in under- 
 
IN THE QUARRY AND THE MINE. 153 
 
 going one kind of change hardening to become stone 
 they have undergone another, splitting up by the gene- 
 ral contraction of the mass; how in some cases the ani- 
 mal or vegetable has been embalmed in a perfect state, 
 while in others we find only its broken shell, a few frag- 
 ments of bone, the impression of a leaf, or the impress 
 where an organic substance has once lain. 
 
 In all these respects quarries are so varied that no two 
 teach precisely the same lesson. Each has its own 
 special fact, and each material has behaved so differently, 
 under apparently similar circumstances, that no monotony 
 need be feared. We may consider quarries as either of 
 granite, basalt, slate, sandstone, or limestone. Chalk, 
 although so soft, is a variety of limestone, and tells the 
 same tale. Marble is a hard variety. 
 
 In granite quarries there is always much grandeur of 
 effect. The rock itself is so hard and tough and heavy, 
 that if it were not for the natural lines of cracks with 
 which it abounds, it would be hardly worth while to 
 quarry it at all. These lines are wonderfully systematic, 
 and they break up the rock into masses of similar shape, 
 large or small, according to circumstances. Much of the 
 value of granite depends on these joints, as they either 
 assist or prevent the obtaining of large slabs or blocks. 
 The great quarries at Peterhead, near Aberdeen, the 
 Cheesewring Quarries in Cornwall, and some others in 
 the British Islands, are remarkable instances of this. 
 The granite in a quarry is not all favorable for working. 
 There will be portions, called veins, exceedingly hard and 
 durable, but by their side will be other veins equally 
 rotten and poor. The grain will be different, the arrange- 
 
154 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 ment of the particles of the stone will vary, and a thou- 
 sand little local peculiarities will exist. It is these that 
 are so instructive. By the study of these the history of 
 granite will have to be learnt; and the direction, number, 
 and magnitude of the different veins will be found to 
 lead to curious generalizations. It is thus that the struc- 
 ture is discovered, and the varieties of structure are so 
 great that no two quarries are exactly alike. 
 
 It often happens that a very wide district will be gov- 
 erned by similar laws with reference to the direction of 
 the principal joints and systems of crevices. There will 
 be an apparent system in all the sides and backs of the 
 rock, a fact which (naturally enough) is known practically 
 to every good quarryman. But these systematic joints, 
 which by the quarryman are only thought of as assisting 
 him in his work of destruction, are recognized and theo- 
 rized upon by the geologist in reference to the nature of 
 granite itself. 
 
 But no granite is without veins of another kind of 
 rock penetrating its mass. These, indeed, are sometimes 
 so large and so numerous as to be intimately mixed up 
 with the rock, but at other times are so small as to resem- 
 ble mere threads. Narrow strings of quartz and broader 
 stripes of porphyry, rotten films of granite and oval blis- 
 ters, as well as other surer indications of great change, 
 and that of a chemical nature, abound. A rough and 
 doubtful appearance of existing in layers or strata is not 
 unusual, but the vein-structure chiefly prevails. If at 
 the sea-side, the waves will have" helped to render this 
 very clear. Sometimes the vein, sometimes the rock, 
 is the hardest; and whichever may be so is sure to be 
 
IN THE QUARRY AND THE MINE. 155 
 
 found jutting out, while the softer portions are worn and 
 eaten away into caverns and recesses. 
 
 Granite generally improves in quality on being followed 
 to some depth below the surface. It has not escaped the 
 effect of weathering, and the stone is often split into 
 fragments too small to be of much use where it has long 
 been exposed to the air. Not unfrequently it is alto- 
 gether rotten close to the surface, and is converted into 
 a mixed mass of rounded fragments and fine sand. 
 However this may be, there is always something to show 
 to the experienced eye the real nature of the case. 
 
 If the chief mechanical lesson that can be learnt in a 
 granite quarry is the curious tendency to split only in 
 certain directions and break up into regular solids, some- 
 times roughly bedded, there is much more to be seen, and 
 even greater difficulties are to be surmounted, if we 
 would understand the structure of slate. Here the whole 
 rock presents material for study. In a large quarry there 
 will be only certain portions that contain the best slate, 
 and many times more of the material quarried is thrown 
 away than can be sent away for sale. But all is charac- 
 terized by the same peculiarity of splitting, carried to an 
 extent almost inconceivable. Throughout not only the 
 whole of a quarry, but often in a large district scores of 
 square miles in extent, is seen everywhere a general tend- 
 ency of all the rock to split in one direction. That this 
 is not the direction in which the beds were thrown down 
 from water is often quite clear, from the position of shells 
 found lying in natural order, and indicating a very dif- 
 ferent arrangement. But this is not all. Besides the 
 cleavage, as the former tendency is called, being that 
 
156 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 according to which the mass can be cleaved or split up 
 into thin plates, adapted for roofing and other purposes, 
 and the bedding, as the latter arrangement indicates, 
 there is also, as in granite, a splitting of another kind, 
 by joints or "backs/' often helping the quarryman, and 
 pointing out to him the direction in which his blast will 
 be most efficacious. These joints, too, are in sets parallel 
 to each other and making definite angles, so that we 
 have in the slate quarry all there is in the granite quarry, 
 and another and more perfect system of splitting in ad- 
 dition to that. Occasional wide fissures in the rock, 
 filled up with a different material, clearly show that all 
 this has not been accomplished without great exertion of 
 force, the nature of which we shall have to consider 
 afterwards. It is clear that slate quarries, even in the 
 simple matter of the structure of the rock, are likely 
 to afford much instruction. 
 
 Limestone quarries are more varied than those of 
 granite or slate. In the first place, the rock is sometimes 
 marble, when the original accumulation by beds or strata 
 is lost; while, most frequently, the bedding is an essen- 
 tial and characteristic feature, replacing, after a clumsy 
 and imperfect fashion, the cleavage of slates. The joints 
 remain, the mass is split into many masses, small near 
 the surface, and gradually more brittle, massive, and 
 compact as we go deeper. But, again, there are dif- 
 ferences in this respect. Some of the limestones are 
 carbonates of liine ; some carbonates of lime and mag- 
 nesia ; some are quite crystalline, some half crystalline, 
 some not crystalline at all. Almost all are cracked and 
 broken near the surface; but, while some are pierced 
 
IN THE QUARRY AND THE MINE. 157 
 
 through and through by crevices and caverns, others 
 seem to have very little of this porous constitution. The 
 joints in limestones are very numerous, and often ex- 
 tremely systematic, being in sets parallel to each other, 
 and making a uniform angle over very wide areas. 
 The hard and most compact and brittle limestones, ap- 
 proaching marbles, are sometimes not at all bedded, or 
 rather, perhaps, this structure is obliterated. The softer 
 and less altered rocks abound generally in fossils, and 
 split easily in the natural beds, some of these serving 
 as good stone, others very poor, and others powdery 
 and bad. In all these cases the crevices are still sys- 
 tematic. 
 
 Sandstones are very generally bedded, but the beds 
 are often thick, and only separated one from another by 
 thin films of iron, sand, or dirt. The harder kinds of 
 sand-rock are always jointed, and the rock breaks accord- 
 ing to this structure. The bedding is often marked by 
 indications of animals or vegetables, but these are some- 
 times mere impressions made by stems of sea- weed drifted 
 upon the sand, or the trails of animals that have passed 
 over the mud while the rock was being formed. 
 
 Quarries in basalt are often in the highest degree 
 picturesque, for they exhibit a curious columnar appear- 
 ance, the result of the somewhat rapid cooling, under 
 peculiar circumstances, of the lava of which the rock 
 consists. That melted rock does cool in these forms is 
 well known by actual experiment, and the magnitude of 
 the mass does not seem to produce any change. Some 
 of the most striking quarry phenomena in existence are 
 derived from huge masses of this kind of material, black 
 14 
 
158 PLACEMENT AND DISPLACEMENT Or STONES. 
 
 and frowning, but of marvellous and systematic regu- 
 larity; the masses breaking up very readily into short 
 six-sided columns, well adapted for certain purposes of 
 construction. On the banks of the Rhine there are 
 many fine instances of the kind ; and other places, where 
 there have been volcanoes in former times, are similarly 
 circumstanced. 
 
 But there is absolutely no resemblance between their 
 appearances and those of rock deposited from water. 
 They clearly show their origin, and this is in all details 
 of structure as well as in general aspect. At a distance, 
 indeed, there is a marked flatness where such material 
 is spread over the earth on a large scale ; for all is rock 
 once fluid from heat, and often it has been poured forth 
 at the bottom of the sea beneath a great pressure of 
 water. 
 
 Quarries, then, each one in its own way, may be 
 regarded as illustrative of the state of rocks after they 
 have been placed, and when they are so far altered as is 
 involved in their being now near the surface: altered 
 by those slow processes that go on out of sight, and 
 deep in the earth, or under the waves, altered by being 
 lifted up, and thus exposed to enormous squeezing, 
 altered, lastly, by exposure to rain and sun, cold and 
 heat, precisely in the way in which these causes of 
 change are most efficacious. 
 
 To obtain good stone, many methods are resorted to, 
 besides merely paring away the surface, and working the 
 hill-side or cliff into convenient steps. Near the city 
 of Caen, whence comes stone that has been used for the 
 last thousand years in the construction of buildings both 
 
IN THE QUARRY AND THE MINE. 159 
 
 in France and England, a very beautiful cream-colored 
 limestone is obtained by long tunnels, run into the earth 
 at the foot of a low cliff by a river. The stone thus 
 reached has not been exposed to weathering, and is much 
 finer and less injured than from parts of the same bed 
 near the surface. Since, also, particular beds are more 
 valuable than others, these must be followed out of sight, 
 since the mass above them could never be removed. 
 Thus the fact of the beds or strata that come out to 
 the surface at one place being continued out of sight in 
 another, is shown by actual experiment. In thus work- 
 ing it is often necessary, for the sake of air, to sink a 
 deep hole or shaft, to meet this gallery run in for the 
 stone, and thus we have the first illustration of mining 
 operations as distinct from quarrying. In one sense, 
 indeed, mining is only quarrying under ground out of 
 sight of day; and when the object of mining is to get 
 coal, this is really all that is needed mechanically. 
 
 Mines, however, generally lay bare other peculiarities 
 of structure, and even of composition, of rocks than 
 those seen in ordinary quarries. In the first place, mines, 
 when not for coal, are generally in districts where the 
 many open spaces in rocks are now filled up, partly or 
 altogether, with foreign minerals. Mining is carried on 
 for ores, or those stones from which metal is obtained; 
 and most of them actually occupy the crevices formed 
 long ago in such rocks, as granite, slate, sandstone, or 
 limestone. Such crevices are then called veins. 
 
 We have seen how systematic the cracks in these 
 rocks are, and now, in reference to mining, this corre- 
 spondence in direction of the chief systems will be found 
 
160 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 to extend far and characterize large districts. If we 
 take Cornwall, our own great mining district, and look 
 at the Ordnance Map, geologically colored to show the 
 rocks and their condition, we shall see a number of gilt 
 lines parallel or nearly parallel to each other, ranging 
 nearly east and west, but crossed by others running more 
 nearly north and south. On looking more closely, the 
 former will be seen to mark the places where the great 
 copper and tin mines are placed; while the latter, if 
 they show mine's, are chiefly lead and silver. Miners call 
 the former, or east and west veins or crevices, by the 
 name of lodes or right-running veins. The others are 
 called cross-courses, and are less valuable. Something 
 of the same kind marks every great mining district. 
 The object of the miner is to discover and reach the 
 deposits of valuable mineral in these veins, and every 
 point of geological knowledge concerning the structure 
 of the rocks is useful to him, in as far as it assists in 
 this. 
 
 Under ground in mines, therefore, as well as above 
 ground in quarries, the geologist must pursue his studies, 
 must compare, and examine, and decide, to the best 
 of his ability, how far the veins affect the rock, or are- 
 affected by it, what are the conditions favorable for ore, 
 and what appearances are deceptive and unfavorable. 
 In these dark recesses he learns many important lessons; 
 he sees under what conditions rocks yield valuable mine- 
 rals, or refuse them; and he learns other lessons, more 
 valuable and instructive, inasmuch as they are less 
 marked and confused with surface-action. 
 
 Thus, then, there are means available in most countries, 
 
IN THE QUARRY AND THE MINE. 161 
 
 and often in many parts of a country, in most rocks, and 
 often in the same rock, under very different conditions, 
 for making out Nature's work, in preparing rocks for 
 their ultimate destiny. Originally the river-bed and the 
 ocean-floor, covered up with other deposits or pressed 
 down by a steady weight of water, exposed to such uni- 
 form temperature as exists in the depths to which they 
 are carried, they gradually lose their first state and 
 acquire some other, according to the causes that act. 
 Drying and hardening, they occupy less space, and crack. 
 Elevated or depressed, they occupy a different space, 
 greater or smaller; they are squeezed, and bent, and 
 altered. Then come those systematic cracks which ter- 
 minate in veins, originally open crevices, but, as time 
 goes on, filled up with various minerals and metals. 
 Ultimately brought near the surface, they are, each time 
 a movement takes place, gradually more and more split, 
 and the original crevices become more and more defined, 
 larger, and more systematic. At length the whole rock 
 is left high and dry, as a part of land, a leaf in our 
 Great Stone Book, having its writing and its illustra- 
 tions, telling its story, and helping to clear up the earth's 
 history. 
 
 Such are some of the lessons to be learnt in the quarry 
 and mine. They are lessons of importance, though not 
 perhaps those that the young geologist would first direct 
 his attention to. Every crevice and joint, every bed, 
 every disturbance indicated by a fracture or heave of the 
 beds, every obscure marking, every portion of the 
 stone, whether selected for superior excellence or set 
 
 14* 
 
162 PLACEMENT AND DISPLACEMENT OP STONES. 
 
 aside as flawed and faulty, affords good material for 
 study. It is here that the plan and course of Nature 
 must be learnt; and it is well sometimes to neglect the 
 fossils, interesting as they may be, for the sake of the 
 laws that have governed the whole deposit. 
 
VOLCANOES AND EARTHQUAKES. 
 
 IN various parts of the earth there are mountains of a 
 sugar-loaf form, having at the top a cup-shaped hollow, 
 instead of rising to a point ; and from within this cup, 
 or from cracks in the side of the mountain, there issue 
 from time to time large quantities of steam, and various 
 stifling sulphurous and other poisonous gases. Showers 
 of fine ashes and lumps of stone are shot out into the air 
 from the same vent with extreme force, accompanied by 
 peculiar sounds proceeding from the very depths of the 
 earth; while floods of melted rock, called lava, pour 
 forth over the land, sweeping away trees and whole 
 villages in their course, filling up the deep beds of 
 rivers, and only terminating when the sluggish stream 
 of boiling lava accumulates to such a thickness at the 
 vent as to overbalance the pressure acting from beneath r 
 and thus close the safety-valve for a time. 
 
 Of all phenomena, these outbursts of fire from the 
 earth are among the most alarming and mischievous. In 
 former times, tens of thousands of victims have been 
 sacrificed to them ; and recently, within a few years, there 
 have been many terrible eruptions recorded, proving that 
 the cause that produced them is still at work, and is 
 
 163 
 
164 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 as capable now as it ever was of overwhelming a city 
 or devastating the richest plains. About fifty years after 
 the death of our Saviour, two important cities in South 
 Italy, Herculaneum and Pompeii, were overwhelmed by 
 loose ashes and melted rock erupted from Vesuvius, one 
 of these mountains; and it has since continued, from 
 time to time, to repeat similar eruptions up to the present 
 day. Etna, another far loftier mountain, in the island 
 of Sicily, has poured forth a burning flood within a few 
 years, and is described, as it appeared some 2300 years 
 ago, by Pindar, one of the earliest poets of Greece, in 
 the following sentence : " The snowy Etna, the pillar of 
 heaven, the nurse of everlasting frost, in whose deep 
 caverns lie concealed the fountains of unapproachable 
 fire; a stream of eddying smoke by day, a bright and 
 ruddy flame by night, and burning rocks rolled down 
 with loud uproar into the sea/' 
 
 Volcanoes are of all elevations. In the year 1831, an 
 eruption took place in the Mediterranean, between Sicily 
 and the site of ancient Carthage, where upwards of a 
 hundred fathoms of water had been proved by sound- 
 ings; and, after this eruption had gone on for some time, 
 an island was formed, which ultimately was upwards of 
 200 feet high and three miles in circumference, entirely 
 composed of incoherent ashes thrown up out of the 
 earth. Other similar eruptions have taken place in the 
 Atlantic in still deeper water. At the level of the sur- 
 face, in many parts of the world, distinct volcanic ap- 
 pearances have often been reported, in Sicily, in India, 
 and in Persia. In India, not very far from the mouth of 
 the Indus, there is a tract of a thousand square miles of 
 
VOLCANOES AND EARTHQUAKES. 165 
 
 country covered with low cones erupted at various times. 
 At Stromboli, one of the Lipari Islands, between Naples 
 and Sicily, is a constant eruption at an elevation of about 
 2300 feet. Vesuvius itself is 4000 feet; Etna is 11,000 
 feet. In the Sandwich Islands, a few years ago, a copious 
 stream of lava, two miles broad and twenty-five miles 
 long, proceeded from an opening 13,000 feet above the 
 sea; while Cotopaxi, one of the loftiest mountains of the 
 Andes, has its cone and crater more than 20,000 feet 
 above the sea. At all elevations there is this mysterious 
 power in the earth's interior exerted, and apparently with 
 little difference at different heights. 
 
 Very widely, too, are volcanoes distributed. There 
 are several in Europe, five of them active; for Etna, 
 Vesuvius, and Stromboli, Santorin in the Grecian Archi- 
 pelago, and Hecla in Iceland, seem to have been for 
 more than twenty centuries continually in readiness to 
 burst forth, although they are not always throwing out 
 a sufficient quantity of matter to do serious injury. Of 
 these the three first are in the South of Italy and ad- 
 joining islands, and are close together; the fourth is 
 some distance towards Asiatic land; but Hecla is far re- 
 moved, touching the Arctic Circle. In Asia there are 
 two principal groups, one near the shores of the Medi- 
 terranean, the other in the central part of the continent; 
 but the Asiatic islands, between the Burmese peninsula 
 and Australia, are everywhere dotted over with active 
 volcanoes, no less than 115 of which have been named. 
 Others are known in the Pacific Ocean ; while the Pacific 
 coast of America, and the whole of Central America, 
 abound with them. 
 
166 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 But we must not measure volcanic agency by the 
 number of volcanoes that have been seen in activity in 
 recent times. Wherever there are peculiar cone-shaped 
 mountains, made up of piles of ashes and molten rock ; 
 and even where the materials are present but the cone is 
 no longer there, we may be sure that the same cause has 
 been at work. There is, as far as we know, no other pos- 
 sible way by which heaps of volcanic ash and lava can 
 have been produced but that of eruption from the earth ; 
 and thus the presence of the ashes marks the existence 
 at one time of the volcano. 
 
 Regarded in this light, there is proof of this reaction 
 of the interior of the earth on the surface this pouring 
 forth volumes of matter, either melted or the result of 
 'heat in many places where there are no volcanoes. 
 Even in the British Islands such proof is not wanting; 
 for the northeast coast of Ireland, at the celebrated 
 Giants' Causeway, and the opposite islands of Scotland. 
 Staffa and others, are remarkable for rocks entirely iden- 
 tical with the lavas of Vesuvius and Hecla. In parts of 
 Europe where no one has seen eruptions there are real 
 volcanoes, as in Central France, and on the Rhine not 
 far from Bonn, in Hungary and in Northern Italy. The 
 East of Europe, the peninsula of Spain and Portugal^ 
 Syria and the Holy Land, the east coast of Africa, 
 many large tracts in Central and Southern Asia, many 
 parts of America, and several of the West India Islands, 
 all present similar appearances; while many islands 
 rising out of the Atlantic and Pacific Oceans are evi- 
 dently due to the same agency. Volcanoes recently 
 active, or indicated by the unmistakable results of their 
 
VOLCANOES AND EARTHQUAKES. 167 
 
 former activity, are thus proved to exist, or to have 
 existed, over a very large proportion of all the land that 
 has yet been visited by man. Whether the interior of 
 Africa and Australia countries that are as yet very 
 little known will prove to have been in like manner 
 visited by volcanic eruption, remains to be seen ; but, 
 certainly, all that is known at present would lead us to 
 doubt whether they are not rather freer in this respect 
 than other tracts of the same dimensions. On the other 
 hand, the bottom of the Atlantic is, beyond a doubt, sub- 
 ject to very serious and, in some places, frequent erup- 
 tions; while parts of the Indian Ocean are yet more re- 
 markable in this respect. 
 
 When, in addition to these proofs of the existence of 
 some wide-spread source of heat in the interior of the 
 earth, quite independent of the warmth obtained from the 
 sun at the surface, we take into account the multitude of 
 springs of hot water that rise out of the earth at various 
 places, and the high temperature that is soon reached in 
 all mines, particularly in those of great depth, we shall 
 be obliged to admit that volcanoes are only vents or out- 
 lets to heated matter far below out of sight. That such 
 heated matter is everywhere present, could we open a 
 communication with the rocks a few thousand yards 
 under our feet, there can be no doubt; and perhaps the 
 occasional descent of water, soon turned into steam at 
 very high pressure, and bursting out with resistless force 
 through the weakest and thinnest part of the covering 
 that presses upon it, may serve as a convenient, if not an 
 accurate, explanation of the cause. Certainly most of 
 the active volcanoes are not far from the sea; and those 
 
168 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 now extinct may be so only for a time, because there is 
 no longer a way for the quantity of water to reach them 
 that is necessary to lift the rocks above. 
 
 Volcanoes are frequently in groups, several within a 
 comparatively small area; and it has often been re- 
 marked that a great eruption happening in one of a 
 group is generally a sign that the others will be still and 
 undemonstrative. In these cases they no doubt commu- 
 nicate, at a certain depth, with some common cavity. 
 There are, however, exceptions to this; for sometimes 
 eruptions have taken place, at no long interval, from 
 craters not far from each other. 
 
 The history of an eruption is the next thing that re- 
 quires to be told. First of all, there are frequently loud 
 noises, so loud as to be heard hundreds of miles from 
 the part of the earth where they are produced. In the 
 year 1835, a noise preceded an eruption from one of the 
 great volcanoes of the Andes, which was heard to a vast 
 distance in every direction. Nor is this a solitary in- 
 stance; for there was a case in 1812, in the West Indies, 
 when the noise was heard over a tract of land and sea 
 about as large as all Europe. Noises are not, however, 
 always heard, and such thunderings as these are com- 
 parati irely rare. 
 
 After the noise, and sometimes without much previous 
 intimation, there issues out of cracks in the ground, or 
 from the cup-like depression near the top of the volcano, 
 a strange mixture of several gases and steam, in a rapid 
 succession of puffs. The gases include much sulphur, 
 which is deposited like soot on the walls of the chimney 
 through which the eruption passes. The steam that 
 
VOLCANOES AND EARTHQUAKES. 169 
 
 rushes out is soon changed into water, which falls in 
 abundant showers of rain, and runs off the surface, 
 carrying with it the sulphur and fine ashes thrown up 
 at the same time. 
 
 Very numerous slight shocks, causing the ground near 
 the place of eruption to tremble, have been next observed; 
 and in some cases two or three hundred such shocks 
 have been counted, at pretty regular intervals, within an 
 hour. They seem to be the precursors of the great out- 
 burst which follows. This consists of an inconceivable 
 quantity of the very finest dust that can be conceived, 
 thrown into the air, sometimes dry, sometimes with steam, 
 but with such enormous force as to be projected quite 
 into the upper part of the atmosphere, where it comes 
 under the influence of steady and strong currents of air, 
 and is sometimes carried for two or three hundred miles, 
 gradually falling, of course, but, owing to its extreme 
 lightness, not previously able to reach the ground. 
 There are cases on record in which this dust has been 
 carried for a thousand miles, covering the ground, even 
 at that distance, to a thickness of two feet. This is 
 about what would happen in London if a similar erup- 
 tion were to take place in Vesuvius; but there is no 
 doubt that the upper currents of air are both more power- 
 ful and steadier near the equator, where such vast dis- 
 tances are travelled by the dust, than in our latitudes; 
 and, in fact, all the remarkable instances of the kind 
 occur in the West Indian and South American volcanoes. 
 Very large stones stones as large as an ox have been 
 described as thrown into the air, and shot to a distance 1 
 of a mile or two, from the Italian and Sicilian volcanoes; 
 
 15 
 
170 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 but the dust does not reach so far as in the cases men- 
 tioned. 
 
 The fine dust of volcanoes is not less remarkable for 
 the quantity that is thrown out, than for the distance it 
 is carried. Cities have been buried and lost in it, and 
 the sea has been rendered almost unnavigable for a time. 
 This dust is the result of a process not much unlike 
 that of blowing off the salt that is sometimes deposited 
 in a steam-boiler at sea; and the ash was originally thin 
 bubbles of lava/ the boiling over of the great sea of 
 molten rock, mixed with steam in place of common air, 
 the bubbles exploding with violence as soon as the 
 pressure is removed. 
 
 After the ashes have been ejected, the next event, in a 
 complete eruption, is the rending open of the side of the 
 mountain, and the slow, majestic pouring forth of a river 
 of melted stone, called lava, which is forced out in a 
 semi-fluid or pasty state, and, after a while, cools and 
 bridges over at the surface. This does not prevent the 
 gradual issue of more and more of the same material, 
 which creeps on, adapting itself to the irregularities of 
 the ground, carrying away every obstacle, filling up 
 great depressions, such as river-channels, engulfing vil- 
 lages or towns, and quite altering the face of the country 
 along its course, burning every thing inflammable, en- 
 closing within itself every thing that cannot be destroyed, 
 and not in any way to be turned from its course. In 
 1822, two streams of lava were poured out from Vesu- 
 vius, the total width of the two being about two miles, 
 and the length of each of them about six miles. In 1852, 
 Etna poured forth a similar flood, which in the first twenty- 
 
VOLCANOES AND EARTHQUAKES. 171 
 
 four hours advanced two miles and a half (about ten feet 
 in a minute on an average), and then continued to move 
 on more slowly for many days. In Iceland, floods of lava 
 have had a depth or thickness of from four to six hun- 
 dred feet; and wherever these outpourings have taken 
 place, whether recently or in times long since past, they 
 have spread uniformly over wide tracts of country, 
 and the same phenomena have been from time to time 
 repeated. 
 
 In all parts of the world, and probably at all periods 
 of the earth's history, the material thrown out from vol- 
 canoes has been alike. Slight differences in appearance 
 and perhaps, here and there, peculiar mineral combina- 
 tions have been observed; but, essentially, all lava and 
 all volcanic ash is the same. The ash is, indeed, impro- 
 perly so called, being merely pumice in a very fine state 
 of division, the pumice itself being only the froth of the 
 melted lava. It is, however, curious enough that mixed 
 with the dust, or forming an essential part of it, the 
 minute flinty cases of the simplest forms of vegetation 
 (Diatomacese) have sometimes been found. 
 
 Volcanoes, then, are the vents or outlets by which the 
 matter beneath the earth's surface when, from any cause, 
 obliged to expand and become relieved from some excess 
 of force or newly-added force is enabled to open com- 
 munication to the day. They are the safety-valves of the 
 fires glowing far beneath our feet, choked and foul, and 
 only available in ease of absolute need, but then yielding 
 and preventing greater injury and irremediable mischief. 
 They indicate, in some measure, where these fires are 
 most active, and show that they form belts or zones in 
 
172 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 various parts of the earth, not always and at all times the 
 same, but shifting in the course of ages, and apparently 
 never very far from positions where water can have occa- 
 sional access. They show, also, that the matter in the 
 earth's interior is singularly alike in all places, and, more- 
 over, that it has always been so. 
 
 The slight shocks that often immediately, and in quick 
 succession, precede a volcanic eruption, occasionally take 
 place on a far grander scale, and at a greater distance 
 from the scene of ultimate outburst. They then act on 
 a larger part of the earth's surface, and produce results 
 which, however terrible, are not difficult to imagine, 
 when the conditions of producing and transmitting an 
 undulation or wave are considered. The earth's external 
 shell that coating of earth and rock which covers up and 
 conceals all the mysteries of Nature's great laboratory 
 is in a general sense elastic. When, therefore, by some 
 means, a convulsive throe takes place, and a certain por- 
 tion of the surface is lifted up by a force which fails to 
 burst through and rend it asunder, the result is, on a 
 more limited scale, the same as would be the case if a 
 sudden wave were formed in water. The motion, once 
 produced, would be communicated to a distance, and thus 
 the convulsive upheaval at a single point would be dis- 
 tributed through a space large in proportion to the mag- 
 nitude and depth of the original disturbance and the 
 degree of elasticity of the rocks. 
 
 But movements are not passed through rocks without 
 some results that are heard and felt by those who in- 
 habit the surface above. Each one involves a shock 
 alike injurious to mechanical constructions, as houses and 
 
VOLCANOES AND EARTHQUAKES. 173 
 
 churches, and alarming to men and animals. Loud roll- 
 ing, rumbling sounds are heard; the earth not only rocks, 
 but wide yawning cracks appear, not, indeed, opening into 
 the interior, but sufficient to be dangerous and terrible. 
 Tough rocks are strained and shaken, brittle rocks are 
 broken, soft rocks are squeezed, and thus a general de- 
 rangement is felt. 
 
 The duration of each earthquake is measured gene- 
 rally only by seconds, or even parts of a second; and as 
 the operation is so brief, and generally quite unexpected, 
 it is by no means easy to obtain observations of time that 
 can be depended on. If the accounts of two or three 
 intelligent witnesses to an earthquake-shock are com- 
 pared, they will generally vary so much as to remove all 
 confidence as to the actual correctness of either. 
 
 Earthquakes have, generally, a distinct course over the 
 earth, and the area within which they are felt, however 
 large, is always limited. By comparing the observations 
 in different places, it is generally possible to mark the 
 range and limits of each shock; and they vary exceed- 
 ingly. There are many small shocks that range only for 
 a few scores of miles, the breadth of the zone affected 
 being only a few miles. A great earthquake will be felt 
 across a continent, or even across the whole breadth of 
 the Atlantic, affecting, in the course of a short time, 
 the coast of Spain, the interior of Scandinavia, Eastern 
 Russia, and Canada, with all intermediate spots, and, 
 almost at the same time, the West Indies and the coast 
 of Africa. 
 
 The proportion of the earth's surface liable to be 
 shaken in this way judging only by the actual expe- 
 ls* 
 
174 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 rience of the last few centuries as recorded in authentic 
 statements would seem to be very much larger than 
 could at first be thought. So completely, indeed, does it 
 include all the land with which we are most familiar, 
 that we can hardly resist the conclusion that no district 
 is free. Earthquakes are very frequent in the British 
 Islands, upwards of a hundred having been recorded 
 within the first half of the present century, this being 
 at the rate of one every six months during the time. 
 In the same half-century about the same number of 
 shocks are described as having been felt in Scandinavia ; 
 but these were not mere continuations of those felt in 
 the British Islands. So, also, of 300 that took place in 
 France, Belgium, and Holland, 170 in the basin of the 
 Rhine and Switzerland, and 150 in the basin of the 
 Danube, by far the larger proportion were limited to the 
 particular district, taking the course of the river-basins 
 and not traceable beyond. In the Italian peninsula 
 there have been nearly 500 within the first half of the 
 century, and in the eastern part of the Mediterranean 
 as many as 200. But throughout Russia, unless the 
 absence of any record is to be accounted for by the 
 apathy and want of habit of recording natural events 
 common with uncivilized and half-civilized people, the 
 earthquakes have been very few; and the same may be 
 said of the interior of Africa. It may be regarded as 
 clearly proved that the whole of the western part of 
 European land is now, and has been for some time, sub- 
 ject to earthquake vibrations, occurring very frequently. 
 Each separate vibration is generally small, few extending 
 beyond the districts in which they seem to have originated. 
 
VOLCANOES AND EARTHQUAKES. 175 
 
 Asia and America are subdivided naturally, like 
 Europe, into earthquake regions; and only the larger 
 disturbances seem to cross the line of demarcation that 
 surrounds each area, which seems generally sufficient to 
 enclose the ordinary and small disturbances. In both 
 countries, and indeed in Europe also, there are at inter- 
 vals catastrophes which are more terrible as the interval 
 between them is greater. About once in each century 
 there has generally been such a catastrophe in some part 
 of the world ; and during the hundred years intervening 
 between great earthquakes the intermediate pulsations 
 have made up in number what they want in intensity and 
 range of action. 
 
 There are very curious facts made out by a careful 
 comparison of known earthquakes and the circumstances 
 that preceded and followed them. Out of nearly six 
 thousand that have been so far described as to have their 
 dates mentioned, considerably more than half occurred 
 during the colder six months of the year; and this 
 general result is rendered more interesting when we find 
 that in each separate earthquake district, taken separately, 
 the result is the same; while if we only take the dis- 
 turbances of the present century the result is even more 
 strongly marked. Grouping the earthquakes in months, 
 we find that the greatest number have taken place in the 
 month of January and the smallest number in July, the 
 proportion being about three to two. So, again, if we 
 divide the year into quarters, we find January, February, 
 and March to be the months in which the greater number 
 have taken place, and May, June, and July the smallest. 
 Thus, in the three first months of the year 1669 are re- 
 
176 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 corded, and in the three early summer months only 1281 
 There seems no way of escaping from the odd conclusion 
 that earthquakes are more likely to take place in cold 
 than in warm weather. 
 
 If, then, volcanoes are safety-valves heavily loaded, 
 which occasionally admit the pent-up vapors from the 
 earth's interior not only to escape, but to carry with 
 them millions of tons' weight of solid matter to the sur- 
 face, and if earthquakes afford ample proof that con- 
 vulsive movements, affecting large but variable tracts of 
 land, are also extremely common, and cannot but affect 
 in a marked degree the countries subjected to them, there 
 appears ground for believing that the ordinary course of 
 Nature provides means for making those alterations of 
 level which we spoke of in the last chapter, and modify- 
 ing the condition and position of rocks at the earth's 
 surface to the extent described by geologists. It remains 
 only to see whether the mere undulation or vibration of the 
 earthquake is accompanied, habitually or occasionally, by 
 a positive and definite change of level of the part of the 
 country in which it occurs. 
 
 The recorded instances are very numerous of perma- 
 nent change of level accompaning disturbances in vol- 
 canic or earthquake districts. In the neighborhood of 
 Vesuvius there is proof of both elevations and depres- 
 sions to the extent of twenty or thirty feet along an ex- 
 tended line of coast and to some distance inland, and this 
 so gradually as not to destroy buildings, but simply sub- 
 merge them when close to the shore. The rate a few 
 years ago was estimated at an inch every four years, but 
 is now different. 
 
VOLCANOES AND EARTHQUAKES. 177 
 
 So lately as in 1835 an earthquake was felt in Chili, 
 between Copiapo and Chiloe, and for some distance out at 
 sea. After the earthquake, ships that had been riding at 
 anchor in upwards of forty feet of water were found to 
 have grounded, and many shoals became quite dry ; while 
 the shore became one mass of recently-killed mussels, 
 chitons, limpets, and seaweeds, still adhering to the rocks 
 on which they had before lived, the sea not rising 
 to within four or five feet of its former level The 
 ground afterwards sunk slightly, leaving, however, a per- 
 manent elevation over an area of some thousands of 
 square miles. A similar result had been produced by an 
 earthquake in 1822, on a still grander scale, over a tract 
 of country nearly as large as Great Britain and Ireland. 
 
 In 1819, after a celebrated earthquake near Bombay, 
 a large district sunk down and became permanently 
 covered with water, while at the same time an adjacent 
 district was raised above its former level. The newly- 
 raised country measures fifty miles from east to west, 
 and is sixteen miles broad. 
 
 It is not necessary to multiply instances of this kind, 
 all tending to prove that the violent shake and disturb- 
 ance noticed during earthquakes may be, and often is, the 
 result of some deep subterranean force lifting up the 
 whole mass of solid matter in its convulsive effort to ex- 
 pand. Sometimes this is followed by a collapse, the rocks 
 afterwards sinking into some vast cavern. 
 
 But we have further proof that even where volcanic 
 eruptions do not extend, there are still upheavals and de- 
 pressions going on, calculated to alter, in time, the form 
 of the land and the proportion of land and water in cer- 
 
178 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 tain districts. In that closed sea the Baltic, where the 
 tides hardly penetrate, and especially in some of the long 
 inlets and gulfs by means of which it penetrates the land, 
 it has long been known that the land is undergoing a 
 slow upheaval. This was spoken of in 1807 by the 
 celebrated German traveller Yon Buch, and it has 'since 
 been proved that there is no doubt of the fact of the 
 rising of the land. Marks were put at various places, 
 natural objects were noticed, and every precaution taken 
 against inaccuracy. The result is a conviction, in the 
 minds of careful observers, that the whole of the land 
 on the upper part of the Gulf of Bothnia is really under- 
 going a steady elevation, while south of that the move- 
 ment, if any, is rather one of depression. 
 
 In many parts not only of the coast of Scandinavia 
 but of our own shores, and indeed all along the Atlantic 
 coast, there are seen at intervals ancient sea-beaches at 
 levels greatly above the highest which the sea now 
 reaches. These show that elevation has taken place to 
 an extent amounting in some cases to sixteen hundred 
 feet, while it happens occasionally that we find at no 
 great distance equally good proof of local depression. 
 While the shells and pebbles that once formed a sea- 
 beach are lifted high in the air, the trees and other 
 objects before above the sea, including even buildings, 
 are occasionally buried many feet deep, and occupy posi- 
 tions quite incompatible with their growth or with their 
 existence as human constructions. 
 
 Thus, then, it appears that by natural causes still in 
 action, more marked in some parts of the earth than in 
 others, but traceable over a large surface, there are 
 
VOLCANOES AND EARTHQUAKES. 179 
 
 changes taking place whose tendency must be to break 
 asunder, compress, and tilt up the various rocks between 
 the seat of disturbance and the surface, However small 
 the result may seem at one operation, still, as it goes on 
 at intervals without limit of time, it must at length pro- 
 duce' large and important consequences. By such means, 
 indeed, all the appearances alluded to in the last chapter 
 can be produced, and all the fractures, elevations, and 
 depressions accounted for. The only element required 
 is time; and if it be admitted that the earth as a planet 
 has been in existence long enough to account in a rea- 
 sonable way for the production of the rocks themselves 
 and their co-ntents, there is nothing more required to 
 account for other movements and changes in position. 
 Some of these have always been going on, contempo- 
 raneously with the deposit of fresh rocks derived from 
 the destruction of the old ones. 
 
 Of the cause of earthquakes and other upheavals of 
 the outer crust of the earth, it is easy to theorize, but 
 difficult to try experiments. They seem, as we have said, 
 to be more common at certain seasons than at others, and 
 they seem also to have some mysterious relation to the 
 moon and sun. How far they are governed by those 
 forces of electricity and earth-magnetism that are ever 
 passing through and round the earth, observation has 
 not yet shown; but that they are parts of a great system 
 not limited to our earth, but influenced greatly by our 
 relations with the sun as the centre of our system, re- 
 cent observation would show to be at least probable. 
 
 We learn by these considerations how little, in any 
 sense, men can claim independent existence. As inhabit- 
 
180 PLACEMENT AND DISPLACEMENT OP STONES. 
 
 ants of the earth we are mutually dependent on each 
 other and on all that lives above, around, or beneath us; 
 but we are not less dependent on the various conditions 
 of matter and on the laws that govern matter. 
 
 Our earth also with its attendant moon mutually in- 
 fluence each other, and much of the change necessary 
 for our well-being is due to the presence of that satellite 
 whose light is the smallest part of its value. Our earth 
 and moon, as one group, form part of a large system of 
 bodies by no . means all similarly constituted or com- 
 parable one with another, but all dependent on a central 
 sun. This sun, with its following, is itself subordinate, 
 and forms a mere unit in a larger system. We know not 
 how, or how far, we have relation with this infinity of 
 bodies in space, but we certainly are influenced by them 
 and it is by such influences and by forces thus widely 
 acting that the earthquake and the volcanic outburst, the 
 storm within the earth, the storm in the air, and the 
 auroral storm far above out of our knowledge, are all 
 governed, and their times and seasons fixed. The laws 
 on which these depend are as definite, and act as com- 
 pletely and freely, as those which are exemplified in the 
 bursting of the leaves in springtide or the ripening of 
 fruit in autumn. 
 
THE DISTURBANCE OF ROCKS. 
 
 LIMESTONES, sandstones, and clays make up a large 
 proportion of those rocks that are commonly met with in 
 England; and when we add to them the varieties of slaty 
 and quartzy rocks, there are only left granite and por- 
 phyritic rocks and basaltic rocks to complete the series. 
 But how is it that we can find opportunity of examining 
 all these rocks in so small a country as England? Do 
 they always appear at the surface in small patches? Do 
 they succeed each other in regular order? Is there any 
 order at all observable with regard to them ? These are 
 questions that the young geologist may be expected to 
 ask, and he must be able to answer them if he is to learn 
 his subject and face its difficulties. Let us in this chap- 
 ter devote ourselves to questions of this kind, and try to 
 make out how and why it is that many rocks, which ap- 
 pear at the same level in traversing a small country, are 
 so often described as overlying one another. Let us add 
 to this an inquiry as to how we are to identify rocks in 
 distant parts of a country. 
 
 Geologists, in speaking of rocks, describe them as lying 
 
 one over another, like a parcel of books heaped upon 
 
 a table. In one place you see the back of one book, 
 
 in another a part of the side of a second. None of the 
 
 16 181 
 
182 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 books reach much above the level of the table, but 
 with a little care you might make out the titles of a good 
 many without moving them, or at least ^ou could recog- 
 nize the bindings if these were different one from another. 
 Fifty books thus heaped on a table might occupy but 
 a small space and no great height ; but it would depend 
 entirely on the way they were heaped as to whether we 
 could make out what they were without moving them. 
 
 Rocks are really found lying one over another in very 
 irregular positions, in a way not much unlike those in 
 which books would be placed on a counter in a book- 
 seller's shop. In such a case there would be in one place 
 half a dozen in a heap, and of these we should only see 
 one side of the uppermost. Elsewhere there are a num- 
 ber placed on edge; but in rocks this is rather an excep- 
 tional position, while in the bookseller's shop it would be 
 the most usual. 
 
 Of a number of books carelessly placed on their edges 
 on a table, the last one will probably have fallen so as to 
 be horizontal, while others of this group will be more or 
 less slanted as they are nearer to or farther from the end. 
 Of the rocks, also, by far the greater number are thus 
 slanted, and this notwithstanding that they have origin- 
 ally been horizontal and are now more or less tilted; 
 whereas the books were originally vertical and are now 
 more or less fallen. Bearing in mind this comparison 
 and the differences, let us study some sea-cliff or railway- 
 cutting, especially seeking for simple and instructive 
 illustrations. 
 
 The journey from London to Brighton is one so 
 very frequently and easily made that comparatively few 
 
THE DISTURBANCE OF ROCKS. 183 
 
 readers will be unacquainted with it. It affords numerous 
 instances of the way in which rocks are arranged, and 
 one in which several can be seen by travelling over a 
 comparatively small distance. 
 
 SECTION FROM LONDON TO BRIGHTON. 
 
 Rocks, Places. 
 
 a. London clay. 1. London. 
 
 b. Chalk. 2. The North Downs above Merstham. 
 
 c. Upper green-sand and gault. 3. Reigate. 
 
 d. Lower green-sand. 4. Horsham. 
 
 e. Weald clay. 5. The South Downs at Brighton. 
 /. Hastings sands. 6. The Sea at Brighton. 
 
 The above Diagram illustrates several important geological points. It is a 
 section across beds tilted in opposite directions, and across what is called a 
 valley of elevation. 
 
 Passing from London, and leaving the slippery clays 
 of New Cross and the clays covered with gravel at Syden- 
 ham well behind, we see near Croydon symptoms of the 
 chalk, which is there not far from the surface. As the 
 chalk is easily reached by boring, not only at and near 
 Croydon but at various points between that and London, 
 there is not a shadow of doubt about the relative position 
 of the clays, the gravel, and the chalk in this district; 
 and when, near the long tunnel at Merstham, the railway 
 passes through a deep cutting, it is easy to see that the 
 beds of chalk there incline towards London. This is 
 seen again when we emerge from the tunnel at Merst- 
 ham ; but not far off the chalk is replaced by the sand 
 hills of Redhill, near Reigate. Now, these sands come 
 out from under the chalk, they are tilted in the same 
 direction and nearly to the same amount, and they are 
 farther from London. They must, beyond all doubt, 
 
184 PLACEMENT AND DISPLACEMENT OP STONES. 
 
 have been deposited below, and therefore before the 
 chalk, and yet they now form hills (Leith Hill, &c.) 
 nearly as high as the top of the chalk-downs. But the 
 parts of the chalk itself that are seen on coming out of 
 the tunnel must originally have been some hundred feet 
 below those seen at its entry ; for all the way through we 
 have been going across tilted beds as shown in the dia- 
 gram, and the beds we first saw have come out at the top 
 of the downs. This, too, corresponds exactly with what 
 we have said about the sands. Advancing farther south, 
 it is soon seen that a bed of clay comes out from under 
 the sands, and at length the sandstones of Tunbridge 
 Wells form hills which were certainly once below the 
 clays, and therefore, it must be supposed, far below the 
 chalk. 
 
 But from about midway between London and Brighton 
 the beds of sandstone, instead of continuing to point 
 towards London, change their direction, and are seen 
 quite as clearly inclining towards Brighton. When we 
 approach Brighton, clays cover up and conceal the sand- 
 stones, sands cover the clays, and soon the chalk once 
 more appears, covering up the sands just as it does on 
 the other side. 
 
 To come back to our illustration of books on a table, 
 it is easy to arrange them so that the appearances we 
 have described should be given in a general way. To 
 do this, we should have to put two books to represent 
 each of the beds, and the middle two must be supported 
 on one which is concealed. Are we, then, to regard the 
 chalk of Merstham and that at Brighton as altogether 
 deposits, always separated as we now see them, 
 
THE DISTURBANCE OP ROCKS. 185 
 
 or are we to look further for information before deciding ? 
 If we examine for ourselves, we shall find that we can 
 actually walk on continuous chalk, always the same kind 
 of rock in every respect, from Beechy Head past Brighton 
 and Worthing into Hampshire, and thence back into Sus- 
 sex and Surrey, till we come to Merstham Tunnel ; and 
 we may then, if we will, follow it to Dover. Thus it ap- 
 pears that our chalk represents a broken book which may 
 once have covered up all the sands, clays, and sand- 
 stones between the North and South Downs, but whose 
 larger and central part has been removed out of sight. 
 So, in the same way, the sands and clays represent other 
 broken books of smaller size. It is not difficult to see 
 that if we wish to account rationally for these appear- 
 ances we must suppose that all the upper beds have been 
 carried away, after having once been lifted up and broken 
 asunder by some slow upheaving force. In this opera- 
 tion of lifting, all that was brittle has of course cracked, 
 and the tough beds have broken after much straining; 
 while the middle tract of country represents a saddle or 
 a ridge having the sides inclining different ways, like the 
 roof of a house. The lowest beds are thus lifted up into 
 the highest position. 
 
 There is clearly nothing unreasonable, still less impos- 
 sible, in this explanation of a series of facts observed in 
 one short trip. We have, while keeping nearly on a 
 horizontal line, made our way over or through, first the 
 gravel and then the clays near London, afterwards the 
 chalk, then a bed of clay, and then again some thick 
 beds of red sand. After this we have crossed some 
 tough clay, different from the first kind, and have come 
 16* 
 
186 PLACEMENT AND DISPLACEMENT OP STONES. 
 
 out into the sandstones of what is known as the Weald, 
 or wooded part formerly (in Saxon times it was all cov- 
 ered with forest) of the county of Sussex. But when 
 we reach a certain point in our journey we find that the 
 beds we had crossed and lost sight of reappear, inclin- 
 ing from instead of towards us; and lastly, going on still 
 farther, we repeat all we have done before, until at 
 Brighton the sea stops our progress. 
 
 This simple example of tilted rocks might be very 
 much complicated if we turned our steps to Wales, or 
 visited Scotland. In those countries, where mountain- 
 masses rise out of the earth, the extent and variety of 
 beds that we cross over is much greater; and we must 
 be prepared for long and complicated series of lime- 
 stones, sandstones, and clays of very different kinds, with 
 occasional interruptions by such rocks as granite and slate. 
 There also the beds are twisted into very peculiar 
 shapes : they are sometimes vertical, and are put into all 
 sorts of strange attitudes, and they are often so changed 
 as not to be recognizable, unless we actually trace them 
 from some point at the surface where they have their 
 usual characteristics, and thus fully identify them. 
 
 On the whole, it is found that by traversing our island 
 from east to west, we gradually pass to rocks which lie 
 under those we have lately visited. Lower and there- 
 fore older rocks gradually become the surface rocks as we 
 get on towards Wales, and the newer or upper rocks dis- 
 appear. No doubt there are some exceptions to this, but 
 it is a good and fair general statement. The chalk is 
 the most easterly, and also the newest, of the great series 
 of lime-rocks of our island; the Portland-stone, which 
 
THE DISTURBANCE OF ROCKS. 187 
 
 comes next in order, is the next older ; the Bath-stones 
 are much older; and the limestones of Clifton and South 
 Wales, which pass into marble, are of yet more ancient 
 date. So it is with the clays and sandstones, speaking 
 always in a general sense ; but, as is the case with the 
 Weald of Sussex, there are many local exceptions, -j 
 
 But are we to suppose that, because the chalk is the 
 uppermost and newest rock and is not found in Wales, 
 it has once been there and since removed? By no 
 means is this necessary j and the pile of books, our first 
 illustration, will still help us out with a suggestion and 
 comparison. The books all end somewhere, and gene- 
 rally soon and abruptly. Similar beds, whatever they 
 are, were not formed at the same time all over the earth. 
 They form patches, sometimes very small, sometimes much 
 larger, but they are never exactly the same in all respects 
 for a very great distance. Often they disappear entirely 
 arid suddenly at a particular place, and in some cases 
 never extended beyond their present limits. 
 
 The beds, or strata, or by whatever other name we call 
 the heaps of one kind of rock found in a certain district, 
 are, beyond all doubt, exceedingly variable in surface, 
 thickness, and form, as well as in material. One is a 
 long stretch of a particular kind of clay, ranging for hun- 
 dreds of miles, but of very small breadth. Such a bed 
 might have been formed on an ancient coast. Another 
 is a uniform and widely-extended mass of sand, here and 
 there mixed with beds of clay, sometimes full of salt, 
 not unfrequently hardened into distinct layers of stone, 
 but always so far the same that we can easily prove the 
 identity. This might have been a sea-bottom, since lifted 
 
188 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 and dried up. A third, and many besides it, may have 
 been composed of limestone separated by animals; some 
 of it by animalcules at the sea-bottom; some by heaps 
 of solid coral pushing out and rising up against the whole 
 force of the waves of an open sea; some of it, again, 
 may be the debris of innumerable shells drifted into a 
 bank by some local current. Every one of these was 
 originally at the bottom of the sea, and owed its origin as 
 well as its form to some local cause which we can now 
 only guess at; but since then all have been moved from 
 their original position, have been covered up in part by 
 other deposits; have become hardened or altered, and 
 have been at length partly pared away while being lifted 
 into the upper air and exposed to the action of weather 
 and water. 
 
 What has happened in England has happened else- 
 where, but by no means always in the same proportion. 
 In some countries, as in the great plain-country of the 
 North and East of Europe, the deposits remain extended 
 uniformly over hundreds of thousands of square miles 
 hardly altered at all from the horizontal position in which 
 they were formed under water. The same is the case, to 
 some extent, in America, where the modern deposits are 
 on a large scale compared with any we have. The 
 interior of Africa, and perhaps much of the interior of 
 Australia, will be found marked with another peculiarity : 
 -they are extensive areas covered^with similar and little- 
 altered rocks. 
 
 On the other hand, in the great chain of the Alps, 
 which runs like a broad lofty wall across the middle of 
 Europe, the appearances of the various rocks are in the 
 
THE DISTURBANCE OF ROCKS. 189 
 
 highest degree complicated and difficult to unravel and 
 explain. Not only are the rocks tilted, but they are en- 
 tirely altered. Limestones and chalk are converted into 
 marble, and all mark of the method of formation entirely 
 lost; sandstones are changed into compact rocks of 
 quartz, abounding with large groups of crystal and many 
 varieties of minerals, which owe their origin to very base 
 and common materials, but which are now so brilliant 
 and rich as to be sought for as stones of great value. 
 
 So, again, the clays are turned into slates, and altered 
 as much in position as in appearance. On the flanks of 
 these mountains the beds are greatly tilted, particularly 
 on one side; while on the other side there has been ab- 
 rupt fracture, and the rocks, broken short off, have been 
 lifted up high in the air, till they now rest against others 
 whose date of formation was far more recent. There 
 is no amount or variety of twisting and breaking and 
 displacement which rocks in such localities do not show; 
 and some of the most striking and noble appearances 
 of Alpine scenery are due to the fantastic and irregular 
 lines into which beds originally horizontal have been 
 thrown. 
 
 Vast gaps are not unfrequently observable, the marks 
 of bedding on rocks of the opposite sides clearly corre- 
 sponding, though now there is a wide interval yawning 
 between them. Jagged peaks rise, and broken ridges 
 extend for long distances, all connected at some ancient 
 period, but rent asunder by the vast force that has ele- 
 vated the mountain-mass and lifted the continent out of 
 which it rises. 
 
 The great mountain-chains of the globe the Alps, 
 
190 PLACEMENT AND DISPLACEMENT OF STONES. 
 
 continued from the Himalayan chain, and the Andes 
 each with important links and spurs being the loftiest, 
 are the youngest of all. Others of more ancient date 
 chiefly affect older rocks, and their axes have a different 
 direction from that of the main chain in the neighbor- 
 hood. There can hardly be difficulty in understanding 
 that the forces sufficient to upheave to the height of tens 
 of thousands of feet these lines of rock, may also have 
 lifted at the same time, but to a smaller extent, wide 
 tracts of flatter country. It is beyond a doubt that the 
 lifting-up of the various continental masses of the earth 
 must be regarded as due to, and of the same date as, the 
 production of the great mountain-chains that form, as it 
 were, a backbone to the land. Thus the chain of the 
 Himalaya Mountains in Asia, stretching into Europe by 
 the mountains of Persia, Arabia, and Turkey, are con- 
 tinuous with the Alps in Europe and the Atlas Moun- 
 tains in Africa. The former chain, uniting with the 
 Pyrenees, reaches quite into the Atlantic on the north of 
 the Mediterranean; while the Atlas Mountains, stretch- 
 ing across Northern Africa, are also continued beyond 
 Morocco, and are lost under the same great ocean. In 
 America there is but one chain, which reaches from the 
 islands of Tierra del Fuego in the south quite into the 
 Arctic Circle, the two great portions of the continent 
 being connected by the mountains and having the same 
 direction. But there are other directions in which land 
 has been elevated, and these no doubt belong to different 
 periods and different mountain-systems. We must not 
 here enter on difficult and disputed geological problems; 
 but it is safe to point out the direction of English rocks 
 
THE DISTURBANCE Ok tOCKS. 191 
 
 and their manifest relations to mountain-chains ranging 
 through Cornwall, Wales, and Scotland, as illustrations of 
 the fact we now allude to. 
 
 Very numerous and important results may be traced, 
 in all mountainous districts, of the force that has acted 
 to bring the mountains to their position. The various 
 beds, once so regular and clear in their arrangement, are 
 now confused and broken. The fracture that has taken 
 place has often rendered it almost impossible to follow 
 the part of a rock that has undergone removal and con- 
 nect this part with the rest. Intervals of many yards 
 filled with rubbish, broken away from the rock or trans- 
 ported from a distance, are seen to exist between the 
 walls of a crevice. Rocks are apparently annihilated, 
 though really they have undergone only a removal or a 
 rearrangement of their particles. New rocks are created 
 out of old materials, and, in a word, the whole aspect of 
 deposits is so altered that it becomes impossible to iden- 
 tify any one of them by its mineral character, or by 
 following it mechanically from one place to another. All 
 that is most picturesque and most pleasing to the eye, as 
 well as stimulating to the imagination, in mountain- 
 scenery, is due to mixed mechanical and chemical action 
 consequent on the great change incurred in lifting the 
 rocks from the bottom of the sea and placing the frac- 
 tured edges in the upper regions of the atmosphere. 
 
 In speaking of the results of such movements, geo- 
 logists have become accustomed to employ a special 
 language. The tilt or inclination of the beds they call 
 the dip; the direction of the line on which the eleva- 
 tion has taken place is the strike: and by observing 
 
192 PLACEMENT AND DISPLACEMENT OP STONES. 
 
 and recording the dip and the strike they decide on 
 the extent and direction of the original disturbing force 
 of the beds presumed to act from below. The fracture, 
 when a bed has been broken asunder during elevation 
 and a part of it protruded above the rest, is called a 
 
 fault or dike 
 ( see diagram ) ; 
 and the ridge 
 or saddle, from 
 which beds in- 
 cline in oppo- 
 site directions, 
 SECTION ILLUSTRATING FAULTS. ^ an anticlinal 
 
 d. A dike. ' /. A fault. axis(sZQ p. 195). 
 
 Besides these, there are some other terms in common 
 use. Thus, the regular arrangement of beds in deposits 
 parallel to each other is conformable stratification; and 
 when disturbances have acted after part of a series is 
 deposited and before the remaining part is completed, 
 so that the upper series is not parallel to the lower, we 
 have un conformable stratification. It will readily be 
 seen that these technical terms are simple expressions 
 of certain facts determined by observation, and neither 
 involve theory nor pretend to give any reason for the 
 appearances they allude to. 
 
 It is not unusual to find as the central rock in a moun- 
 tain-chain, or projecting from the flanks as a subordinate 
 range, very large quantities of that peculiar mixed rock, 
 made up of hard crystals imbedded in a hard matrix, to 
 which the name of granite is popularly applied. Such 
 rock appears to have been formed at great depth, under 
 
THE DISTURBANCE OF ROCKS. 193 
 
 a heavy pressure of overlying earth or water, and at a 
 temperature high compared with that of the earth's sur- 
 face, though not necessarily high compared with molten 
 rock such as is poured out from volcanoes. Great chemi- 
 cal changes were needed to convert any mixture of lime- 
 stone, sandstone, or clay into this material, although the 
 ultimate elements are not different; and it is quite con- 
 sistent with all that we know of the origin of granites 
 that they should have been produced far down below the 
 earth's surface, and that a very long time should have 
 been occupied in preparing them. 
 
 The very great amount of expansion and contraction 
 that must have taken place while these rocks were in 
 preparation and when they were afterwards elevated, and 
 the pressure thus exerted on all adjacent matter, will 
 account for some of the most singular and otherwise in- 
 explicable appearances presented by the clays and lime- 
 stones near them. In this way the slates and marbles 
 grew out of the simpler and more mechanical deposits, 
 and while this was being done those numerous cracks 
 and open fissures were produced, which, being afterwards 
 filled up, became mineral veins. The systematic nature 
 of these veins is due, no doubt, to the regularity of the 
 condition under which the whole change was effected. 
 The filling up with mineral wealth is a later operation, 
 and one requiring much attention and study to compre- 
 hend. 
 
 The reader may see that, in thus speaking of rocks 
 originally placed at the bottom of the sea and now lifted 
 up to occupy positions in upper air so far removed from 
 their origin, it has been taken for granted that certain 
 
 IT 
 
194 PLACEMENT AND DISPLACEMENT OP STONES. 
 
 movements have occurred upon the earth; and it may 
 seem almost necessary to assume that these must have 
 been on a far grander scale ; and therefore more destruc- 
 tive, than any that living men can either have experienced 
 or imagined. It may be thought that catastrophes are in- 
 dicated involving the destruction of all that was living 
 upon the earth at the time, that the whole world groaned 
 and was troubled at these upheavals, and that each one 
 of them must have involved a special and manifest inter- 
 position of the Creator who has so wisely and so well 
 ordered terrestrial affairs. 
 
 I believe that there is no greater or more mischievous 
 error than this. I say no greater error, because it 
 assumes the Law of Nature to involve a system of inter- 
 ferences, not of adaptations; and to intelligent human 
 beings, endowed with divine intellect, interferences, if not 
 manifestly called for to answer a special moral purpose, 
 denote weakness and partial knowledge. On the other 
 hand, a system so contrived as to involve, in its very 
 nature, a complete and continuous growth and adaptation, 
 indicates perfect foreknowledge and wisdom. I say, 
 also, no more mischievous error; for by habituating the 
 mind to look for an escape from all difficulty by mira- 
 culous intervention, the student of Nature would not only 
 become accustomed to a comparatively low view of 
 Almighty Power, but would cease to search, in the right 
 way and the right spirit, for those hidden Laws of Nature 
 which can alone assist him in comprehending and ex- 
 pounding the great universal history which it is the 
 province of Science to lay open before men. 
 
 It must never be forgotten that the study of every 
 
THE DISTURBANCE OF ROCKS. 
 
 195 
 
 department of Science and Natural History the effort 
 to acquire every knowledge useful to or attainable by 
 man is but one of many ways of exercising those 
 powers with which man has been endowed ; and that the 
 due exercise and cultivation of all his powers, what- 
 ever they may be, is the clear and obvious duty of every 
 human bein^. 
 
 (tt) ANTICLINAL AND (*) SYNCLINAL AXES. 
 
 See page 192. 
 
THE GREAT STONE BOOK. 
 
 PART IV. 
 
 17* 
 
 
% fcfodflfc. 
 
 WHAT THE PICTURES ARE, AND WHAT THEY MEAN. 
 
 IN the last chapter we arrived at the conclusion that, 
 provided time enough were allowed, the changes in posi- 
 tion that have brought to the flanks and summits of lofty 
 mountains various beds of rock, formed originally at the 
 bottom of the sea, might be well accounted for without 
 assuming violent and sudden disturbances to have taken 
 place. The disturbances and movements of land, whether 
 of elevation or depression, have indeed been so small at 
 any one time within human experience, that one's first 
 impression is that they must be insufficient; and it is 
 only by careful and continued observation that we recog- 
 nize them as possible. But when we examine carefully 
 the rocks themselves, and those remains of animal and 
 vegetable existence they generally contain, we find time 
 as necessary here as elsewhere. 
 
 When speaking of limestones, sandstones, and clays, 
 the fact that the former rocks almost consist of, and the 
 others generally contain, remains of living things, was 
 alluded to, and some results stated. These remains were 
 once called petrifactions, or things turned into stone; 
 they are now often called fossils, or things dug up; and, 
 considering that they must necessarily be dug out of the 
 earth before we can examine them, the change of name 
 
 199 
 
200 THE PICTURES IN THE BOOK I 
 
 does not seem of much importance. At first it may 
 appear strange that any thing that has once formed part 
 of a living substance should be petrified or turned into 
 stone. Still more strange will it seem if (as is the case) 
 the details of structure are preserved in the stone; so 
 that, without much difficulty, the most minute and com- 
 plicated peculiarities, whether of shell, bone, or wood, can 
 be examined under the microscope in the fossil state, 
 after the conversion into stone, quite as well as if recently 
 obtained from a living specimen. This is effected in a 
 manner not very easy to understand, since the original 
 substance must be removed, and the new one supplied 
 particle by particle; and this must have taken place not 
 unfrequently while lying on the ground, or scarcely buried 
 more than a few feet in the earth. There can be no 
 doubt, however, as to the fact; inasmuch as both wood 
 and coral, and occasionally shells and bone, are found in 
 the transition-state, consisting partly of the original and 
 partly of the replacing mineral. It is something like 
 those curious metamorphoses we read of in the ancient 
 poets; and we occasionally so far penetrate the mystery 
 of Nature's laboratory as to be able to see the change 
 partly effected, if not in actual progress. 
 
 Organic Remains is another name given to these proofs 
 of former life; and it is the most accurate term of all. 
 Whatever we choose to call them, they are very widely 
 spread, occupying a part of every rock originally formed 
 in water, though often injured or almost obliterated. Nor 
 is this very wonderful. The mud and gravel accumu- 
 lated at the bottom of water is likely to have retained, 
 mixed up with its particles, fragments of the shells, 
 
WHAT THEY ARE, AND WHAT THEY MEAN. 201 
 
 bones, or other animal substances accidentally introduced, 
 and belonging originally either to the inhabitants of the 
 water or adjacent land; while, if these fragments should 
 happen to be long rolled about with sand and pebbles, it 
 is equally clear that little would remain to denote their 
 origin, or at least little that could be distinguished by the 
 unassisted eye. Such remains of animals and vegetables, 
 when met with, may be regarded as the Pictures in the 
 Great Stone Book of Nature, illustrating the story told 
 in other language in the text of the book itself. 
 
 There is hardly a river that now enters a lake or the 
 sea, there is not a coast-line in any part of the world, 
 and it would seem that there is hardly a spot buried 
 under tens of thousands of feet of saltwater between 
 England and America, that has not, resting on, buried be- 
 neath, or drifting along its bottom, a multitude " which 
 no man can number" of the shells, the encrusted cases, 
 the external or internal skeletons, the teeth, and other 
 remains of animals living near. These are the illustra- 
 tions vividly representing the conditions of existence. 
 Of the myriads of animals that pass along, carried by 
 the water, the greater number serve as food to other 
 animals of larger proportions, and thus become imme- 
 diately reconverted into organic structure. Many more, 
 when dead, become the prey of minute creatures, which 
 soon reduce them to their parent dust, with no trace left 
 of their former existence. Some decay and fall to pieces, 
 and are thus altogether lost; while of the rest the harder 
 parts may be buried under favorable conditions. Of 
 these last only it can be that a few, in the course of time, 
 undergo the change which fits them to serve as perma- 
 
202 THE PICTURES IN THE BOOK! 
 
 nent records of the age in which they flourished. How 
 few this is in proportion to the whole number how 
 partial and imperfect is the record of former times thus 
 handed down to posterity may be imagined by those who 
 will take the trouble to search for themselves, in recent 
 formations, for evidences of the life of the district. But 
 the real poverty of the record can hardly be thus appre- 
 ciated; because it is quite impossible for us to know how 
 much, or rather how little, is preserved in the larger de- 
 posits, owing to there being no means of looking forward 
 in time, and anticipating the amount and extent of the 
 destruction that will follow the decay that now goes on, 
 and that conceals the real nature of organic substances 
 during their conversion into new minerals. 
 
 It is, indeed, wonderful in the highest degree that, in 
 spite of all causes of destruction and all changes of ma- 
 terial, so great a variety of remains as those already de- 
 scribed should have been preserved and discovered by 
 geologists. A few centuries ago, the very existence of 
 fossils was hardly known as a fact (m which an argument 
 could be based. For a long time the fact of their having 
 really belonged to animals and vegetables was doubted. 
 Afterwards, many rocks were considered as being quite 
 without fossils which now are known to contain them in in- 
 finite abundance; and although each year still adds to the 
 number and variety of the different species, and intro- 
 duces us either to new localities for known species or 
 new species from the known localities, there are yet many 
 naturalists and geologists who are unable to recognize the 
 probability that our knowledge of the subject is still 
 
complete 
 
 WHAT THEY ARE, AND WHAT THEY MEAN. 203 
 
 .C 
 
 very imperfect, and ought not to be assumed as 
 
 in any department. 
 
 Remembering what has been said of the resemblance 
 of the strata in the earth to a heap of books on a table, 
 we may carry on the illustration a little further in re- 
 ference to the subject of Fossils. We have called our 
 earth the Great Stone Book, the leaves of the book being 
 represented by the various strata or beds of stone. We 
 might, indeed, for some reasons, have called it the Stone 
 Library; but it is a library in great confusion; for the 
 books, which in this illustration represent the beds, are 
 piled irregularly on the floor. Each book tells its own 
 story, and describes a history in some measure independ- 
 ent. It is true that many stories are too long to be told 
 in a single volume, and require a complete series; and 
 we must further assume that the Stone Books have been 
 accumulated on the floor of the World-Library as they 
 have been thrown off from the press. If the original 
 order of precedence has been disturbed, it is by some 
 accident from without, and very rarely indeed have any 
 been shuffled in between others previously placed. In 
 this sense, the fossils are the literary contents of the book. 
 Some are very distinct, and mark an important epoch; 
 some are very commonplace, and record facts which may 
 have happened at any time. Many are so obscure in the 
 language and dialect in which they were written, or so 
 injured by time and damp, that they are hardly legible. 
 Some are in black-letter, some in bold, large type ; some 
 are very minute, requiring assistance to read them. A 
 vast number of the series are absent, not perhaps alto- 
 gether, but, at any rate, in the parts of the library we 
 
 
204 THE PICTURES IN THE BOOK: 
 
 are allowed to examine; for we may assist the compari- 
 son by supposing that we are only able to reach the sur- 
 face of the books, after removing an accumulated dust 
 and rubbish like that which has buried the ancient city 
 of Pompeii. 
 
 This illustration by no means exaggerates the diffi- 
 culties that have to be overcome in endeavoring to obtain 
 a knowledge of the ancient natural history of the world 
 by a careful examination of the fossils. A large mass of 
 evidence exists-, but it is often, and indeed generally, 
 abundant only in reference to particular deposits, or cer- 
 tain kinds of animals and vegetables, never complete, 
 even for a single period. 
 
 It is very important that the imperfection of the series 
 of rocks and fossils should be clearly understood; for 
 without it the real value of this kind of evidence can- 
 not be estimated. As far as it goes, it is sound and 
 thoroughly to be depended on; for if the books that 
 form the collection were thrown into the library as they 
 successively got ready, the general sequence must be 
 perfect. In other words, a book at the bottom or in the 
 middle must belong to an earlier date than a book at the 
 top. But, just as the work of printing may have gone 
 on more rapidly in one country or at one period than at 
 another, while sometimes, owing to revolutions or dis- 
 turbances, an interval may have elapsed when literature 
 was dormant, so we find among the fossils that the con- 
 ditions under which they were accumulated were some- 
 times favorable and sometimes the contrary. Sometimes 
 the accumulation was rapid for a time in one country, 
 and altogether stopped in another; sometimes long in- 
 
WHAT THEY ARE, AND WHAT THEY MEAN. 205 
 
 tervals would take place, when Nature seems to have 
 been idle over a large area; and not unfrequently ac- 
 cumulations of enormous extent and thickness belong to 
 one not very long period- 
 
 Without tiring the reader with further continuance of 
 this comparison, let us now consider what kind of re- 
 mains of animals and vegetables are found fossil, and 
 how far they characterize particular periods or deposits. 
 
 Beginning with the most simple forms of life, we find 
 the vegetable and animal so nearly alike that it is scarcely 
 possible to decide clearly the real difference that sepa- 
 rates them. Each is a single cell or small closed bag, 
 often coated or defended with flint or limestone. Every 
 part may absorb, separate, grow, divide, and decay, all 
 with extreme rapidity; and each new offspring generally 
 retains at first some sort of connection with the original 
 parent. Often we find a compound animal or vegetable 
 made up of tens of thousands of the simple individual, 
 and possessing a kind of independent existence. The 
 whole solid structure produced by the compound being 
 may, however, be so minute as to require a microscope to 
 see it; and millions of such specimens of existence make 
 up a bed of mud such as is found at the bottom of deep 
 water in the Atlantic and in other oceans. 
 
 It may be supposed that such mud, some of which is 
 flinty and some calcareous, will remain unaltered, except 
 indeed by hardening and drying, for a very long time. 
 Some of it, perhaps, is as old as any thing that has been 
 made by living beings in the whole earth. And such 
 kinds of life vary wonderfully little, whether found in 
 deep or in shallow water, whether existing in hot water 
 
 18 
 
206 THE PICTURES IN THE BOOK I 
 
 at or near the Equator, or in freezing water in the Arctic 
 or Antarctic Circles. They serve as indications of the 
 fact that "there was life:" the command of the Al- 
 mighty had gone forth, and had been obeyed. Such life, 
 however, being in itself the simplest, can hardly exhibit 
 change, and is repeated from generation to generation 
 as Time advances towards Eternity. Such life existed 
 at the beginning, and the exact analogue exists now. 
 
 Sponges are familiar, because often they are large- 
 sized representatives of this great class of beings whose 
 existence is almost as much vegetable as it is animal, in- 
 asmuch as the characteristic and essential peculiarities of 
 animals and vegetables have not yet appeared in their 
 structure and habits. Sponges are found fossil in a great 
 variety of rocks, some with a kind of simple skeleton 
 of limestone, others with flint, and some merely horny, 
 without much mineral. Certain forms of sponge belong 
 apparently to one period or one set of strata rather than 
 to another, but they can rarely be regarded as distinctive. 
 
 Remains of trees abound in coal, and in the sandstones 
 and half-slaty beds among which coal is found. Not 
 only the trunks but the leaves, and in some rare cases the 
 fruits and flowers, are well preserved; but they are almost 
 always insufficient to give such an idea of the plant that 
 it can be identified. One remarkable fact, however, is 
 clearly made out by these discoveries, namely, that 
 plants and trees allied to ferns, not only small but of the 
 very largest dimensions, were extremely common, and 
 contributed more than any other kind of vegetation to 
 the formation of coal, and to supply the more common 
 fossils of the coal measures. 
 
WHAT THEY ARE, AND WHAT THEY MEAN. 207 
 
 Of animals, almost all kinds have left some indication 
 of their existence, but chiefly, as might be expected, 
 those provided with hard and indestructible parts. Thus, 
 corals, both the more delicate horny varieties and the 
 hard-plated kinds such as build reefs, are very common, 
 indeed, among the most common of all fossils. Nor is 
 this wonderful. The animal that separates the coral 
 from sea-water, and builds up a living wall against which 
 the waves can make no impression, a wall extending for 
 thousands of miles, rising to the water's edge from a 
 depth of a thousand feet, has been in many cases assisted 
 by Nature in a wonderful manner in producing an abid- 
 ing monument. There are many parts of the Pacific in 
 which such works are being constructed, and there are 
 others in which, having been built, they are being pre- 
 served from destruction. A reference to almost any 
 limestone or clay rock will show their presence in some 
 form or other, and thus, being among the things easily 
 and well preserved now, and found in most rocks what- 
 ever their age may be, they are doubly useful; for they 
 not only afford opportunities of comparing the varieties 
 common at different periods, as marked by rocks higher 
 or lower in the series, but they enable us to obtain a 
 continued series or chain of forms, and thus to learn that 
 at all times similar causes seem to have produced like 
 results. It is also extremely convenient, as well as a 
 striking proof of the vast changes that have come over 
 this part of the world, that we are thus able to study the 
 structure of coral-banks in the lofty limestone-cliffs of 
 Cheddar and in the wave-worn shores of Lough Earne, 
 as well as in the upheaved coral-islands of the Southern 
 
208 THE PICTURES IN THE BOOK: 
 
 Sea, 1 ?. In the fields about Steeple Ashton, every stone 
 turned up by the plough is a coral; and our inland quar- 
 ries and chalk-pits afford materials for the study of a class 
 of animals almost wholly wanting on the present shores 
 of Europe. 
 
 A marked peculiarity of structure has been noticed in 
 the corals found in the lowest deposits, most of these 
 having their small cups or stars in rays numbering four, 
 eight, or twelve (or other multiples of four), while the 
 more modern kinds are in groups of six. It has not been 
 found possible at present to suggest a reason for this; 
 but so it is. It is one of the differences produced in the 
 course of time, having reference, perhaps, to some cause 
 of which other indication is lost. It is one of many 
 similar differences unaccounted for and apparently arbi- 
 trary, but not the less real, and often of great value as 
 guides in comparing and identifying the contents of dif- 
 ferent rocks. 
 
 Star-fishes and sea-urchins are members of a family of 
 stone-plated animals, having structure and habits exceed- 
 ingly curious, but still having more or less of that com- 
 pound life that is so remarkable in the coral animal as 
 well as in many small inhabitants of the deep. 
 
 The stony parts of these animals are as widely spread 
 and as common in all rocks as the corals; but they 
 never form such large masses, and indeed are very seldom 
 accumulated in heaps, being rather distributed through 
 the deposit, and mixed up with other fossils. When 
 complete, nothing can be more exquisitely beautiful or 
 ingenious in their arrangement and fitting than the 
 myriads of little stones that build up stars, lily-shaped 
 

 WHAT THEY ARE, AND WHAT THEY MEAN. 209 
 
 cups growing from long stems, grotesque round boxes 
 covered with warty projections, strange sweeping net- 
 like branches, serpent-like forms radiating from a central 
 point, and a hundred indescribable shapes assumed by 
 these fossils. They are most of them represented by 
 species not very uncommon in various seas. The serpent- 
 like stars (Ophiuridse) have been dredged up alive, in 
 mid- Atlantic, from more than a thousand feet of water : 
 the star-fishes and sea-urchins are common enough on 
 our own shores as well as elsewhere. We know their 
 curious habits, feeding for the most part on offal, moving 
 in some strange way by a thousand little suckers, their 
 stone jackets pierced with minute pores, through which 
 the animal imprisoned communicates with the outer 
 world. We know also the risk they are subject to, and 
 the shelter they generally obtain by concealing themselves 
 under stones or in mud; and we recognize their peculiar 
 habits, and the half-compound nature of their life, when 
 we see them jerk off important portions of the body if 
 interfered with, or fall to pieces (some of them, at least) 
 when thrown suddenly into water. All these habits 
 also belonged to similar animals whose remains are found 
 fossil; and the abundance of the fragments, compared 
 with the comparative scarcity of the complete shell, is 
 proof that the old habits were identical with the modern 
 ones. 
 
 Multitudes of peculiar forms of these curious animals 
 are found fossil, some totally different from, others very 
 nearly resembling, those now found and belonging to 
 living animals. Now that we know them to be able to 
 live in very deep water, we may account for their wide 
 
 18* 
 
210 THE PICTURES IN THE BOOK : 
 
 occurrence in most rocks. The oldest rocks contain the 
 least familiar forms. 
 
 It is a curious thing to notice the division into five 
 parts of most of these animals found living, and to find 
 that in many of those whose remains are in the lower 
 deposits this tendency is not so evident. 
 
 Worms and such-like animals would naturally be rare 
 in a fossil state, as being seldom provided with any solid 
 framework. Still there are indications, even of the soft 
 kinds, preserved permanently in numerous worm-tracks 
 that were left on the muddy shores of ancient seas. It is 
 also a habit with many of these creatures to coat them- 
 selves with sand or little pebbles for protection; and as 
 the cases thus made do not die with the animal, if not 
 exposed to violence they will remain buried in the mud. 
 Such worm-cases have been met with in some rocks, and 
 a kind of natural armor with which a few of the same 
 class of animals is provided also remains without change. 
 The tubes which such animals have bored are also some- 
 times recognizable. 
 
 Insects, though they have horny cases, are not likely 
 to be much mixed up with river-mud ; still less can they 
 be carried out to sea in large quantities and buried in 
 deposits at the bottom of deep water. No wonder, then, 
 that it is a rare event to discover such creatures. Buried 
 occasionally by some accident, and caught up from time 
 to time in the resinous fluids oozing out of trees and hard- 
 ening in the air, there is a possibility that a few might be 
 found ; and perhaps, on the whole, the number actually 
 discovered is more rather than less than could have been 
 expected. 
 
WHAT THEY ARE, AND WHAT THEY MEAN. 211 
 
 On the other hand, crabs and lobsters and other 
 marine animals, coated in a thick shell of limestone, 
 which they from time to time throw off, are much more 
 likely to be common. Under favorable circumstances, 
 very considerable numbers of them have been met with, 
 and they fully justify the expectation. Such animals 
 are common on rocky shores, where there are occasional 
 beds of mud and sand in holes, and they are not found on 
 all shores. Neither are their remains in all rocks ; but 
 enough have been detected in the older as well as newer 
 rocks to render it certain that the old seas and shores 
 resembled the modern in the existence of creatures of 
 this kind. 
 
 There are some shells belonging to very minute crus- 
 taceans (as this group of animals is called) that would 
 hardly be recognized as of the same family as crabs ex- 
 cept by the naturalist. Some of these are exceedingly 
 small and simple, resembling in shape the pod of a bean, 
 and the two shells together not unlike a bean, but smaller 
 than a small pin's head. Myriads of such little shells 
 are found in certain clays, and they even help to build 
 up some clays and limestones. Some of them mark the 
 presence of fresh water, or, at least, seem to show that 
 where they were accumulated fresh and salt water were 
 mixed, or, in other words, that the bed of clay or lime- 
 stone in which they are found was deposited near the 
 mouth of a large river. Such conclusions may be the 
 more depended on when other remains of animals also 
 indicate the presence of land not far off, and when frag- 
 ments of the vegetable kingdom are well preserved. 
 
 In some beds near the bottom of the series are found 
 
212 THE PICTURES IN THE BOOK : 
 
 crustacean shells of the most curious form (Trilobites), 
 belonging to kinds not now known in a living state. 
 These are also exceedingly abundant, and with them are 
 fragments of a kind of lobster, that must have attained 
 a length of as much as seven feet. 
 
 In all seas there are found some specimens of a 
 curious kind of bivalve tough shell, pierced through the 
 extremity of one valve with a hole, through which is a 
 bundle of silky fibres attaching the animal to the rock. 
 The modern kinds are called lamp-shells, and within the 
 shell there is, generally, a delicate loop or screw of stone. 
 Most of those now obtained are from rocky bottoms and 
 in deepish water ; and, though found in almost all seas, 
 they are nowhere very common. Of such shells there are 
 specimens in almost all rocks, showing extreme differences 
 of form and many singular peculiarities of structure. 
 There is hardly a single group of deposits that we can 
 examine, from the lowest to the most recently formed, 
 that has not some of them. There are specimens of all 
 dimensions : some covered with long spines, some per- 
 fectly smooth; some thin, others enormously thick and 
 heavy; some quite simple, others extremely complicated; 
 and many of these, that have been buried for ages, could 
 with difficulty be distinguished from shells taken from a 
 living animal. 
 
 While there is this vast variety and abundance of the 
 lamp-shells, now very rare, there are also many deposits 
 of limestone almost made up of other shells. More than 
 a third part of all known fossils are bivalve shells, and 
 another third univalves, leaving only the remaining third 
 for all other species of animals. There is, however, a 
 
WHAT THEY ARE, AND WHAT THEY MEAN. 213 
 
 curious difference with regard to them. Of the species 
 of bivalves, or double shells, such as the oyster and 
 cockle, whose habitations consist of two shelly or strong 
 cases enclosing the animal, there are twice as many varie- 
 ties found in rocks as are now found in the sea; while 
 of the univalves or single shells, such as the snail, the 
 whelk, and others, there are one-third more from the 
 modern sea-shore than from all rocks. 
 
 The variety as well as the absolute number of indi- 
 viduals in the remains of these animals is exceedingly 
 great; nor need this be a matter of surprise, when it 
 is considered how easily they form part of any deposit 
 rapidly brought together, and how slowly they decay and 
 alter if not at once crushed. Formed of limestone, they 
 are sufficiently liable to injury to be quickly broken when 
 rolled about on a sea-shore, though even under such cir- 
 cumstances the number of fragments could not fail to be 
 very manifest; but once buried, they are hardly exposed 
 to other danger. For a long time they retain their color, 
 for a much longer time all those distinctive marks by 
 which shells are recognized and known one from another; 
 and even when, as sometimes happens, they are turned 
 into crystal, whether of limestone or flint, they still retain 
 their exact shapes, and can often be known as well as if 
 they had undergone no change. 
 
 Very beautiful and very curious are the shells that are 
 found in various rocks. Those from the chalk differ ex- 
 ceedingly from those we are familiar with on our own or 
 other shores ; those from the limestone below the chalk 
 differ from the chalk varieties ; and those from limestones 
 lower still in the series are again quite different. Shells 
 
214 THE PICTURES IN THE BOOK : 
 
 found in deposits of clay differ greatly from those found in 
 limestones, and singular changes of appearance are observ- 
 able even in very similar deposits, provided specimens are 
 taken in different parts of a great series. Among modern 
 shells the nautilus is one of the most curious; and as the 
 animal that constructs it much resembles the common 
 cuttle-fish, whose skeleton, or bone (as it is called), is 
 constantly found washed up by the waves on a sandy 
 shore, there is a good deal of interest in all that relates 
 to it. Rare as the nautilus now is, and confined to the 
 Southern hemisphere (the Argonaut of the Mediterra- 
 nean being a different animal), it is remarkable that there 
 should exist in England numerous beds containing mil- 
 lions of shells having similar structure, and certainly once 
 belonging to creatures of similar habits. These almost 
 build up some of the limestones, and are also found in 
 some of the clays. Together with the lamp-shells (the 
 Terebrattda is a familiar group), the Ammonites (twisted 
 shells divided into many chambers) make up a large pro- 
 portion of the whole number of fossil shells. 
 
 Remains of fishes, often very small and not readily dis- 
 tinguished, but sufficiently determined to leave no doubt 
 as to their true nature, are found, as might be expected, 
 in deposits from water. Not only teeth and occasional 
 bones, but scales, are easily preserved; and it seems that 
 the scales are the parts by which the nature of some fish 
 is best known. Sharks very often have spines stick- 
 ing from the back, to which fins are attached; and such 
 spines, being excessively hard and indestructible, are 
 among the parts of fish found in the oldest rocks. The 
 skin of sharks is likewise very durable. From those that 
 
WHAT THEY ARE, AND WHAT THEY MEAN. 215 
 
 live now we obtain shagreen, and small bits of similar 
 substances are buried in many rocks. Some kinds of 
 fishes, very rare now and known to inhabit only a few 
 rivers and lakes, are enclosed in a kind of box of bone, 
 and coated with the hardest enamel. Complete or partial 
 coats of mail, evidently belonging to similar fishes, have 
 been obtained among fossils for comparison with them. 
 The teeth of some fishes are like pavements, excessively 
 hard, flat, and all connected together- other fishes have 
 numerous rows of sharp hooks, others teeth like brushes, 
 and others delicate teeth like the finest needles. Speci- 
 mens of all kinds are found in the earth in beds of all 
 ages; but the scaled fishes we are now most familiar with 
 must either have been rare in former times, or the others 
 must have been much more favorably placed for being 
 kept buried in rocks for many ages. 
 
 Of all land-animals, certain reptiles are those which 
 have the most chance of their remains being preserved. 
 Wrapped up in a bony coat, which prevents injury while 
 alive, the whole framework of the creature holds toge- 
 ther long after death; and as the reptiles thus armed 
 live chiefly near water, and are often buried in deep mud 
 for a long time during dry weather, they must constantly 
 be exposed to be covered up permanently and retained 
 in deposits under course of formation. The scales, teeth, 
 and bones of such reptiles (crocodiles, alligators, &c.) are 
 naturally to be expected, therefore; but no one could be 
 prepared to expect the singular richness of many masses 
 of clay and limestone in such fossils, for we know of 
 nothing in existing creation that could afford a standard 
 of comparison. Not only remains of common kinds, but 
 
216 THE PICTURES IN THE BOOK: 
 
 numerous complete skeletons of others not now known, 
 point to the fact that such animals were once plentiful 
 and lived in multitudes in these latitudes. 
 
 Serpents and frogs are, of course, much less liable to be 
 retained, even if buried in water and mud. A few of 
 them have been found, but they are rarities. 
 
 Birds would seem hardly more likely to be buried in 
 mud than land-animals; but as some of them make the 
 sea their chief resort, and many others inhabit land close 
 to water, it is not surprising that a few remains of them 
 are from time to time discovered. Still, the bones of 
 these creatures that have been obtained from the different 
 rocks, except those of the very latest date, are, with one 
 or two rare exceptions, few and not very instructive. 
 
 Mammalia, with the exception of whales and dugongs 
 and such marine monsters, can only live on land, and 
 most of them seem to require considerable tracts of land. 
 Islands even of large size are often almost without such 
 animals at the present time, and this must always have 
 been the case in the world's history. And although 
 large tracts of land may always have had numerous 
 quadrupeds, and have been crossed and drained by rivers, 
 which carry down rnud in large quantities to the sea, and 
 with the mud remains of all that dwelt on the river- 
 banks, there are so many chances of accident to these 
 that they can only rarely have been preserved. Even 
 when they reach the sea it will be found that, before 
 being in a state fit for handing down to future times, 
 they have for the most part suffered so much from de- 
 composition, and from rubbing about among stones and 
 against each other, as to be hardly recognized. Thus 
 
THEY ARE, AND WHAT THEY MEAN. 217 
 
 there is no likelihood of large quantities of such remains 
 being found under any circumstances, and their total 
 absence might indicate much rather the absence of large 
 continents than the absence of all land. It is quite pos- 
 sible that there might be large deposits going on, in 
 which remains of shells and corals should be very com- 
 mon and remains of fish and reptiles by no means rare, 
 but in which were no remains of laud-animals. Such 
 deposits might even be greatly influenced by the vicinity 
 of a large group of moderate- sized islands, and yet, until 
 man should visit these islands, no quadruped larger than 
 a rat might exist in them. Such would be the case now 
 in some of the islands of the Pacific on a small scale, 
 and may have happened elsewhere on a larger scale. We 
 must not conclude that, because no bones of quadrupeds 
 or birds were buried with the reptiles and fishes, or with 
 innumerable shells and corals, there were no birds or 
 quadrupeds near; still less are we justified in saying that 
 there were none anywhere at the date of the deposit. 
 
 From this account it will be seen that, whatever there 
 is living upon the earth, in the air, or in the water, 
 indications of such life may be met with buried in the 
 mud at the bottom of the sea, or built up with the lime 
 stones and other rocks, as illustrations of the state of life 
 when such rocks were formed. We also see that very 
 imperfect knowledge would be obtained from these ac- 
 cumulations as to the relative abundance or importance 
 of the animals. The point really decided is, which ot 
 them have been best able to resist the causes of decay 
 and destruction, and which were most conveniently at 
 hand to be caught up in the deposit. 
 19 
 
Chapter ilje $ {j 
 
 ANCIENT FORESTS AN3> MODERN FUEL. 
 
 ANY one travelling a few hundred miles through Eng- 
 land, on one of our great lines of railway, north or west 
 of London, can hardly fail to be reminded of the magni- 
 tude and importance of the coal interests, some part or 
 other of which he must traverse. Somersetshire, South 
 Wales, Warwickshire, Staffordshire, Lancashire, York- 
 shire, Durham, and Northumberland, exhibit portions of 
 a vast chain of mineral fuel, of which the under-ground 
 links reach from the fertile valleys of the west to the 
 storm-beaten shores of the northeast of England; and 
 if the journey is farther extended, Scotland will be 
 found to comprise a second and outer line equally mani- 
 fest, and in its way not less valuable. 
 
 Through this wide extent of British lands, it is true 
 that coal is rarely seen at the surface, except when 
 brought there by the active industry of man. From 
 various depths, varying from a few yards to a third of a 
 mile, up pits and shafts, sometimes simple enough in 
 their structure, sometimes exceedingly elaborate and 
 costly, but almost always lifted by the aid of steam- 
 power, the coal is brought to the surface, and, when 
 there, is distributed and conveyed to its destination. 
 The thousands of men and boys, the numerous horses 
 218 
 
ANCIENT FORESTS AND MODERN FUEL. 219 
 
 employed, and much of the machinery, all these are 
 out of sight, and we see only the result; our eyes are, 
 perhaps, offended with the interruption and injury to 
 fine scenery by the unpicturesque surface works and 
 heaps, or we are annoyed by the smoke vomited forth 
 from the chimneys of the numerous steam-engines; and 
 we throw ourselves back in the railway-carriage, indif- 
 ferent and wearied, caring nothing and thinking nothing 
 of those vast mines of wealth we are passing over, com- 
 pared with which, the gold of California and Australia, 
 and the diamonds of Grolconda, may be regarded as un- 
 important. 
 
 Or should we pause, and endeavor to make ourselves 
 familiar with coal as it exists in the earth, and compare 
 its appearance there with its aspect on our fires or in our 
 cellars, the effort, which is one involving no trifling 
 amount of fatigue to those not accustomed to under- 
 ground travelling, might result in a notion more confused 
 than useful; and if we had previously any book-know- 
 ledge of the subject, we should, perhaps, come away with 
 the conviction that written and published descriptions of 
 such matters were far more interesting than the reality. 
 
 A visit to a coal-mine is not, however, without mean- 
 ing, especially to any one who has some little idea of 
 mining operations. The descent through hot air, foggy 
 with floating particles of coal, the darkness and gloom 
 but very imperfectly revealed by candles or lamps, the 
 crowd of trucks, horses, and men at the bottom, and the 
 incessant clanking of the machinery, all these prepare 
 the visitor for his work. Once landed below, he is led 
 past vast furnaces, burning day and night to create a 
 
220 THE PICTURES IN THE BOOK. 
 
 draught of air, on which the very life of all those em- 
 ployed under ground depends; he is told that air close 
 to him, passing into the chimney a little above his 
 head over these fires, is highly explosive, so that a spark 
 entering it would involve destruction ; he is introduced 
 first through broad and then into narrower paths, where 
 the roof has once come down, or the floor squeezed up; 
 he sees men working with difficulty, picking a deep 
 groove in a black wall, and he hears, when away from 
 the work going on, a dull singing noise of escaping gas 
 always oozing through the coal. At one place he is 
 shown where tons of roof have recently fallen, and at 
 another cracks, whence hogsheads of fiery gas are issuing 
 with rapidity, poisoning and rendering dangerous all the 
 air of the mine. He is taken along miles of a vast black 
 tunnel, cut through the mineral, and the road is to him 
 a perfect labyrinth, though really designed and executed 
 on an admirable system. At last he is brought, some- 
 how or other, to a pit-bottom, whence he is lifted, greatly 
 to his satisfaction, to the outer world, and finally he makes 
 his way to a warm bath and pure air, and endeavors 
 to remove, as far as possible, the marks of his visit from 
 his skin and lungs. 
 
 We have said that the impression made on an intelli- 
 gent person by such a visit is not without some good 
 result. He learns at least to estimate the nature and 
 extent of the deposit; he sees some of the peculiarities 
 connected with its position in the earth; he feels some 
 of the difficulties and recognizes some of the dangers of 
 under-ground engineering; and he wonders that men can 
 be found who, for moderate wages, will undertake mining 
 
ANCIENT FORESTS AND MODERN FUEL. 221 
 
 as a regular employment, and give up so much of the 
 satisfaction that all human beings must have in seeing 
 the light of day and breathing the fresh air. 
 
 But while looking at the black mineral, cut through 
 with a pick, or blasted with gunpowder under ground, it 
 may occur to him to look back to the period when this 
 material was first formed or deposited, and consider the 
 circumstances under which it became coal. 
 
 The floor of the coal in other words, the earth on 
 which we tread in a coal-mine is generally a bed of 
 bluish clay; and if a specimen of this clay is brought 
 up and examined, it will perhaps be found loaded with 
 innumerable black stringy markings, crossing each other 
 in every direction. These were once the rootlets of 
 plants, that either grew in this clay as a vegetable soil, 
 or were matted up with it into a tough mass before the 
 plants had decayed. Overhead there is generally sand- 
 stone, and on the roof, where the sandstone and coal were 
 once in contact, we may often see long flat markings, the 
 stems of ancient trees that had not entirely decayed when 
 the sands buried the whole mass. Thus the coal lies upon 
 a clay on which plants grew, and is covered with a mate- 
 rial that contains innumerable marks of similar vegetation. 
 Whatever the thickness of the coal in the regular coal 
 deposits in England, these conditions of the rocks above 
 and below are singularly uniform. In France, especially 
 in the small coal districts in the west and south, such is 
 not the case; but the coal is there generally of different 
 quality, and has been accumulated in a different way. 
 
 The first thing that is learnt on examining coal deposits 
 in England is, that they are generally pretty uniform in 
 
 19* 
 
222 THE PICTURES IN THE BOOK. 
 
 character and thickness over several square miles of 
 country. In some countries, especially in the Northern 
 States of America, near the Ohio, where the extent of 
 coal is enormously greater than in England, this regu- 
 larity is far more striking than with us; but it is always 
 observable. Beds of coal, varying in thickness, but each 
 retaining its own thickness, or nearly so, are found lying 
 one above another, and form a long series. Many are 
 thick enough to be worth working, and each of these is 
 known by some local name; others are only just thick 
 enough to be recognized as coal, forming a thin black 
 ribbon among the rocks; but all are generally so circum- 
 stanced, with reference to the clay below and sand above, 
 as to be easily known to those accustomed to look for 
 them. The clay jbelow, with its rootlets (the under -clay), 
 and the sandstone or other rock above, with leaves, twigs, 
 and trunks of trees, these are almost but not quite in- 
 variable accompaniments. 
 
 It is impossible not to conclude, from all the circum- 
 stances connected with coal deposits, that this mineral is 
 the remains of an ancient vegetation, growing on or near 
 the place where we now find it. Even the coal itself, 
 black and opaque as it seems, yields under the searching 
 power of the microscope some evidence as to its own 
 origin. When ground down to the thinnest possible 
 slice, and carefully examined under a high power, traces 
 are seen here and there of spiral vessels, such as belong 
 to woody fibre, and of some other marks proving a com- 
 plicated vegetable structure. 
 
 Fruits, such as nuts of strange forms, and even delicate 
 flowers, have also been detected. Examples of each of 
 
ANCIENT FORESTS AND MODERN FUEL. 223 
 
 the two principal divisions of vegetable structure, derived 
 from the mode of growth, have been identified. Insects, 
 and other animals, have been found, and proof exists in 
 abundance that all coal was formed near land, if it did 
 not actually grow on the soil with which it is now buried. 
 
 It is worth while to look back into Nature's history, 
 and endeavor to reproduce a chapter of the Stone Book, 
 in reference to this subject. There is a good deal writ- 
 ten, and the illustrations are ample. 
 
 From a pile of rubbish near the shaft of a coal-mine 
 it would be difficult to take up a dozen specimens of the 
 peculiar hardened blue clay, called shale, so abundant 
 in such places, without finding in some of them impres- 
 sions of leaves ; and a very little examination and com- 
 parison would suffice to enable any one accustomed to 
 plants to refer these to some kind of fern. Why these 
 fossils should be so invariably fern-leaves, instead of 
 leaves of the forest-trees (which one might have expected 
 to form at least some part of the deposit), is perhaps the 
 first question that would suggest itself to any one who 
 was desirous of obtaining information concerning the re- 
 mains of a former world. 
 
 A more thorough examination, and a visit to local 
 museums, where such things are collected, arranged, and 
 exhibited, would, however, show that, though not entirely 
 absent, leaf-fragments of other plants than ferns are so 
 exceedingly rare that they may practically be disregarded 
 in considering the important contributories to coal. 
 
 Either of two causes may have brought about this 
 result. The other plants may have been absent alto- 
 gether, or they may have been less easily preserved, when 
 
224 THE PICTURES IN THE BOOK. 
 
 buried perhaps under water in the conditions favor- 
 able for making coal out of wood. Experiment has 
 shown that the leaves of our forest-trees decay much 
 more rapidly than fern-leaves, and thus there may have 
 been large accumulations of the former that have disap- 
 peared, although they have helped to make coal; but the 
 vast multitude of ferns seems, of itself, to show that these 
 were really predominant, and a further study of the trunks 
 of the trees points to the same conclusion. 
 
 Remains of the trunks of trees are sometimes very 
 numerous and very large in the sandstones near coal, and 
 numerous fine specimens have also been found in the 
 shales or clayey beds, especially when these, instead of 
 sandstones, rest upon the coal, forming a roof. In fact, 
 it would seem generally that the greater number of re- 
 cognizable fossil plants occur in this position, heaped as 
 it were on the top of the vegetable mass that has been 
 converted into mineral fuel. 
 
 Let us now endeavor to reproduce an ancient forest 
 such as existed in and near our island at the time when 
 the great mass of our coal was in preparation; and, as 
 far as the materials will justify, let us also people this 
 forest with animal life. In the half-title to this part of 
 the book will be found an art representation that will help 
 the reader in forming an opinion. 
 
 Such a forest certainly abounded with lofty plants of 
 ferns, like those we now call tree-ferns, and to such an 
 extent that in many places it probably contained little 
 else. As, however, in Norfolk Island and other parts of 
 the Antipodes, where such vegetation now prevails, the 
 outskirts of the thick forests may have exhibited a con- 
 
ANCIENT FORESTS AND MODERN FUEL. 225 
 
 siderable admixture of other trees, and here and there 
 groups where the ferns were absent. Pines of large 
 dimensions were certainly among these occasional trees. 
 
 Let us look a little more closely at the trees which 
 seem to have been the chief agents in supplying mate- 
 rial for coal. There are many portions of large trunks, 
 many markings of the bark, many casts of the interior, 
 and not a few fragments, which show the texture of the 
 wood, the springing of the branches, and the attachment 
 of the roots. Occasionally the structure of the wood can 
 be examined under the microscope; but this is a rare 
 exception, for the stone is generally not in a state to 
 admit of this minute examination. 
 
 There are three kinds of trees exceedingly unlike one 
 another that appear to have combined to form a very 
 large proportion of the actual coal. Each of these may 
 have been represented by a great variety of species; but 
 as, on the whole, it is the habit of plants, when they 
 grow freely and abundantly, to exclude strangers, so there 
 may have been then but little admixture in the depths of 
 the forest. We can in a general way understand the ap- 
 pearance and nature of these three kinds of ancient forest- 
 trees. 
 
 Crowds of lofty trunks (Sigittaria), not scaled like 
 pines, but fluted like the columns of a temple, rise before 
 us in groups, each trunk terminating in a magnificent 
 crest of fronds, some drooping over, some curling in 
 curious contortions towards the light. Whether of the 
 dark green of some of our ferns, or of the bright metal- 
 lic tint of others, these ferns, forming the capitals of 
 natural columns, must have presented a strange appear- 
 
226 THE PICTURES IN THE BOOK. 
 
 ance. Thickly grouped, they must almost have excluded 
 light from the ground, and thus there was, perhaps, only 
 a small amount of other vegetation, except where an 
 opening occurred. Rapid growth and equally rapid decay, 
 in a moist atmosphere, and under a clouded sky, would 
 accumulate a vast amount of vegetable matter in such 
 forests in a short time, and it would be left to the 
 insects to destroy the fallen wood. Should it happen 
 that the land was swampy and insects not abundant, the 
 trees might accumulate and form a thick mass of half- 
 rotten matter. 
 
 The trunks of these trees would not seem to have 
 been very solid, or at least the interior was liable to decay 
 more rapidly than the bark. Flattened stems that have 
 belonged to trees three or four feet in diameter, and from 
 forty to fifty feet high, are not uncommon. Others have 
 been found larger, and some that were, perhaps, double 
 the height mentioned. At regular intervals the chan- 
 nelled stem is deeply marked by curious scars, the 
 places on which leaves or fronds have formed and grown, 
 and from which they have fallen. Within the thick 
 bark there was woody tissue, growing, like that of ferns, 
 by additions above and not around. Thus, a young fern 
 now will shoot up and become a tree by degrees, and even 
 assume the proportions of a lofty tree; but all this time 
 it does not enlarge its bulk, and is rarely branched. 
 Trees of this kind continue to grow in height as long as 
 they live, and break off near the root when once dead. 
 
 The roots (called Stigmarm) of these singular trees 
 were not at all less remarkable than the trunk. Large 
 circular roots passed off in every direction from the base 
 
ANCIENT FORESTS AND MODERN FUEL. 227 
 
 of the trunk, like the spokes of a wheel. Each main 
 root had its offsets of smaller size, and each one of these 
 its leaf-like, long rootlets, spreading in every direction, 
 and producing that complicated mass of tendrils found 
 in the beds of under-clay that serve as floors to the coal. 
 Thus, this tree, instead of seeking food from the air by 
 a complicated apparatus of branches, twigs, and true 
 leaves, obtained what nourishment it required from the 
 earth, and passed this food, by circulation, through the 
 lofty vertical trunk to the fronds at the top. The roots 
 and rootlets remain in the clay, little changed even when 
 the trunk and fronds have been converted into coal, and 
 have lost all traces of their original form as well as of 
 their texture. 
 
 Such would seem to have been the condition of one 
 of the principal trees of the coal period. How long it 
 continued, how often it was repeated, why these parti- 
 cular trees rather than others were so frequently accumu- 
 lated in thick masses on the ground, we cannot tell. 
 These speculations we must leave for the present. 
 
 Another very different tree demands our attention. 
 Lofty, and having the proportions of firs, such trees (Le- 
 pidodendrori) shot up into the clouds on a mountain- 
 side, and yet they present the peculiarities of leaf-vege- 
 tation of the club-mosses. New Zealand and other moist 
 insular climates present us with club-mosses, not unlike 
 dwarf trees ; but these are only a few inches high : the 
 coal seems to show us these magnified into forest vegeta- 
 tion. There are trunks twenty to fifty feet high, branch- 
 ing and forking in a peculiar manner, and scarred like 
 pines. The stems of such trees were like those of ferns, 
 
228 THE PICTURES IN THE BOOK. 
 
 and must have grown by additions to the extremity; the 
 leaves, or whatever they may be called, delicate feathery 
 filaments, pointed at the end, shot out from the stem ; 
 and there were no twigs. The fruit grew at the ex- 
 tremity of the branches, and resembled the very long- 
 cone of a fir. Trees such as these are not rare, but they 
 do not seem to have been so numerous as the other kind 
 we have attempted to describe. Their remains are found 
 in similar localities. 
 
 A third singular form of vegetation is before us, a 
 gigantic reed, made up, like a bamboo, of numerous 
 joints, hollow and cylindrical, now only to be seen 
 crushed and flattened, and often only known by the 
 markings it has left on stone. This tree (the Calamite) 
 was limited to swampy places, and was there exceed- 
 ingly common. It is met with wherever coal is found, 
 and the varieties of detail are very great. Some na- 
 turalists have thought that it resembled those marsh 
 plants called mare's-tail (Equisetum), so common in our 
 own country. Some have referred to it as a variety of 
 plants with true woody structure, increasing by an annual 
 thickening of the wood under the bark. Leaves seem to 
 have proceeded in a fringe-like form from each joint, and 
 branches were given off at intervals. Nothing is known 
 of the fruit. These trees were sometimes thirty or forty 
 feet in height, and two or three feet in diameter. The 
 trunk was deeply fluted, and at each joint there was a 
 flat plate or diaphragm crossing the stem. 
 
 Numerous varieties of tree-ferns, such as still abound 
 in the Southern hemisphere; very tall, coniferous trees, 
 like the great Araucaria of Norfolk Island; several palm- 
 
ANCIENT FORESTS AND MODERN FUEL. 229 
 
 trees, bearing fruit not very different from some forms of 
 dates; these, and a multitude, of other plants, have been 
 found buried with the sand and mud that have, in course 
 of time, made up the rocks we now call coal-measures. 
 These, then, with the nondescripts we have endeavored 
 to picture, formed the vegetation of north temperate land 
 during the coal period. 
 
 With these plants the remains of a few insects have 
 been found, including among them a scorpion. There 
 were also a number of small lizards, and perhaps some 
 larger reptiles. Little else is known of the inhabitants 
 of the land at this distant period. There may have been 
 many whose remains were not preserved. There may 
 also have been many whose remains are safely buried, but 
 which have not yet been turned up. Judging from the 
 number and variety of additions within the last few years, 
 since attention was directed to the subject, the last hypo- 
 thesis is probable enough. 
 
 How have these ancient forests been converted into 
 coal available for fuel? How have they been buried 
 under such thick masses of stone and clay? How have 
 they been broken up into compartments and tilted at high 
 angles, as they are found to be in our English coal-mines ? 
 And, lastly, how have they been brought into their pre- 
 sent accessible position? These are questions of great 
 interest, not very easily answered without some knowledge 
 of the general history of the earth in respect to other 
 rocks. Let us consider each in its turn. 
 
 The essential difference between wood and coal consists 
 in the replacement of the water always found in fresh 
 vegetation by gases never found there in a free state. 
 20 
 
230 THE PICTURES IN THE BOOK. 
 
 It is perhaps quite impossible, by any artificial drying 
 short of charring, to deprive wood so completely of 
 moisture that the part still left behind shall not inter- 
 fere seriously with the value of the material as fuel; 
 for so long as any water is present the whole of it 
 has to be evaporated into steam before available heat is 
 obtained, and the heat lost in this process must be de- 
 ducted from the heat-giving power of the fuel. Coal con- 
 tains no water, but, on the contrary, it holds a certain 
 proportion of hydrogen and some oxygen gas; but these 
 help combustion rather than hinder it, and are useful for 
 other purposes. There is also another difference between 
 wood and coal, indicated by the closer texture of the 
 latter. The cellular condition of the wood is, in fact, 
 altered, and the water-contents of the cells must be 
 removed or decomposed before coal is produced. This 
 chemical change has never been produced artificially, 
 either in the case of green wood, dried wood, the black 
 wood obtained from ferns and bog, or various deposits in 
 the earth, nor with such vegetation as peat. All these 
 still contain water : they do not contain gas, and they 
 are not dense and compact stony substances. 
 
 Nature would seem to require a long period of time 
 and certain conditions of heat and pressure to bring 
 about the required result. The woody matter originally 
 accumulated has been buried with clay and sand. The 
 whole together has been sunk down into the earth, and 
 has then been gradually covered up with newer deposits, 
 until it has reached a depth where the temperature is 
 high enough for the chemical change needed. For 
 thousands and tens of thousands of years the ancient 
 
ANCIENT FORESTS AND MODERN FUEL. 231 
 
 forests have been thus exposed, and at length the work 
 is done, and coal has replaced wood, sand has become 
 sandstone, and clay shale. Who can say how long the 
 beds may have remained after this change, or when the 
 movements took place that have brought the whole again 
 to the surface? 
 
 But still the question remains, how have so many suc- 
 cessive deposits of vegetable matter been produced in so 
 narrow a space ? Perhaps, in the absence of facts bear- 
 ing on the inquiry, it is safer to leave this great diffi- 
 culty without an attempt at solution. That sometimes 
 the trees grew on the clay where their roots still remain, 
 and on which the coal now lies, would seem unquestionable. 
 That in other cases the whole mass of vegetable matter 
 has been conveyed from a distance, and has been mixed 
 up with marine remains, is equally certain. We may so 
 easily lose ourselves in conjectures as to the best explana- 
 tion, not only of the repeated depressions of the surface 
 that admitted of a succession of deposits, but of the 
 mere fact of the accumulation of vegetable matter in a 
 state of decomposition, that we are obliged to imagine 
 rather than able to investigate. It is something in these 
 cases to recognize a difficulty. 
 
 The deposits of vegetable matter, sand, and mud, 
 once converted into coal, stone, and shale, in horizontal 
 and parallel layers, the mechanical uplifting could only 
 have been caused by some great force acting from below, 
 and upheaving, with resistless power, the whole mass. 
 But in such upheaval, whether slowly or rapidly per- 
 formed, whether a succession of violent earthquakes 
 has jerked mountains into the air, or, which seems more 
 
232 THE PICTURES TN THE BOOK. 
 
 likely, a gentle pulsation has by degrees brought up 
 the mass, at the rate of only a few inches, or at most 
 a few feet, in a century, in any case there must have 
 been fracture of the brittle minerals, partial upheavals, 
 separations of beds and liftings up of one part higher 
 than another, tiltings up of certain strata and droppings 
 down of others, accompanied by a washing away of loose 
 material from the surface, especially when the elevation 
 has brought surface-beds under the influence of the sea- 
 waves. Thus have been produced all those results that at 
 first seem so strange; and the reader may safely accept 
 this as the explanation of the third and fourth queries. 
 
 We may now proceed to the consideration of another 
 matter concerning these ancient forests, and learn, if 
 possible, how far they could have grown in the climates 
 in which they are now found. The great beds of coal 
 are very widely spread, and fossil remains of plants very 
 nearly allied to each other, if not identical, range at 
 no very distant intervals throughout the whole of the 
 north temperate zone, and extend even within the Arctic 
 Circle. Similar trees appear to have inhabited the coun- 
 try now occupied by the European continent, the northern 
 part of North America, and even China and Japan. 
 Similar trees occurring over this wide tract presume a 
 similar climate everywhere and some means of communi- 
 cation. There is no other condition of land conceivable 
 than a vast archipelago, a countless multitude of islands 
 of various sizes, but with no continued continent, studded 
 over the whole area. Such an archipelago exists to some 
 degree in the South Atlantic Ocean now, and is there 
 accompanied by a condition of depression admitting of 
 
ANCIENT FORESTS AND MODERN FUEL. 233 
 
 the growth of coral islands with extreme rapidity. Such 
 an archipelago, we must suppose, then occupied the whole 
 Northern hemisphere in temperate latitudes. If there 
 were masses of land without mountains in the Tropics, 
 and no land whatever in the Arctic Circle, the conditions 
 would be still more favorable. 
 
 And the climate that would belong to lands so placed 
 may be guessed at with tolerable certainty. The outly- 
 ing islands near Great Britain, in spite of the great mass 
 of continental Europe, possess climates so equable as to 
 astonish all those who first make acquaintance with them. 
 With an average temperature not much higher than that 
 of London, we have here, in spite of cold northerly 
 winds and the ice in the Atlantic, spots where snow is 
 rarely seen and water hardly ever freezes. The vegeta- 
 tion of the South of Europe easily adapts itself there; 
 the orange-tree and the arbutus ripen their fruits in the 
 open air, and delicate flowering shrubs, elsewhere confined 
 to the greenhouse, here adorn the garden during the 
 whole winter. 
 
 One step further a change that should remove these 
 islands from the influence of cold land-winds would as- 
 similate their climate very closely to that of the islands 
 near Australia, where ferns are the prevailing vegetation, 
 where they grow to gigantic size, and are accompanied 
 by trees perhaps the nearest in many respects to those of 
 the coal period. This change would be effected if, in 
 place of the Alps and the land ranging northward towards 
 the pole, there were a sea covered only with islands of 
 moderate elevation. 
 
 There is really nothing, so far as the present know- 
 20* 
 
234 THE PICTURES IN THE BOOK. 
 
 ledge of coal-plants indicates, which requires for their 
 production more than that amount of warmth with moist- 
 ure and that absence from chilling cold that belongs to 
 islands in temperate latitudes with no adjacent large con- 
 tinent. The conditions of the Southern hemisphere are 
 in no way remarkably favorable in these respects, though 
 much more so than in the north ; for there the continu- 
 ous ice extends actually much farther from the pole than 
 it does in the Northern hemisphere, and floating ice 
 reaches to latitudes which correspond with those of the 
 Mediterranean islands. The extreme of equable climate 
 is certainly not obtained on any part of the present sur- 
 face of the earth, and the conditions are nowhere such 
 as to suggest that a limit of warmth and moisture has 
 been approached. 
 
 On the other hand, it is certain that the present land 
 in the Northern hemisphere must have been submerged 
 during the whole time of deposit of the great series of 
 rocks which we now find overlying the coal measures. 
 It is not only a conjecture, but a certainty, that this was 
 the case, since all these are marine deposits and loaded 
 with marine productions. The changes of level that 
 have brought the coal within reach have been alone suffi- 
 cient to lift all the land of the Northern hemisphere from 
 deep water. 
 
 We are, then, at liberty to assume that our ancient 
 forests grew on islands of various dimensions near the 
 present deposits of coal, if not on those actual spots. 
 These islands, if at no very great distance asunder and 
 if connected by marine currents, might easily have had 
 similar vegetation ; they might even have possessed iden- 
 
ANCIENT FORESTS AND MODERN FUEL. 235 
 
 tical species. That such islands should have a rapid 
 succession of forest-growth and a quick accumulation of 
 trees and vegetation in their hollows, with but few ani- 
 mal inhabitants, is probable ; and that they should have 
 been subjected to occasional depression is only what we 
 find now in the Southern seas. There is no reason to 
 doubt that there would be warmth and moisture enough 
 under such circumstances to account for a rank growth 
 of ferns and palms, mixed with gigantic pines and per- 
 haps a few forest-trees, resembling those which we still 
 possess. 
 
 The extent of accumulation of vegetable matter re- 
 quired to produce a single bed of coal of moderate 
 thickness is, however, so great, and the number of coal- 
 seams in a single district is so considerable, that one 
 is lost in astonishment at the magnitude of the result. 
 Even if the whole growth of wood be taken, the time 
 required to produce an acre of coal a foot thick from an 
 acre of forest would, under any circumstances of growth, 
 amount to many centuries; and it cannot be supposed 
 that any thing like the whole growth could be secured. 
 Look at it as we may, the mere heaping together of the 
 raw material for those scores of millions of tons of fuel 
 annually consumed in England is a subject that must 
 ever present great difficulty to understand, and the more 
 so as we are unable to point to any thing in recent times 
 strictly analogous. 
 
 And the interval of time that separated the ancient 
 forests from the human period, when their remains were 
 first to be extracted from the earth as modern fuel, is not 
 one of the least remarkable subjects for contemplation. 
 
236 THE PICTURES IN THE BOOK. 
 
 Each step in the operation demands so much time and 
 has been followed by such long repose each bed has had 
 to be so hardened and altered, and afterwards lifted and 
 depressed and lifted again, before other beds were placed 
 upon it in their turn that one is lost in the endeavor to 
 trace the history and connection of the various movements, 
 and read the succession whose broken links are seen in 
 the different intervening strata. 
 
 Perhaps there is no geological question that admits of 
 closer discussion none in which the evidence adduced 
 is larger in amount or more satisfactory in its nature, and 
 at the same time none in which the general conclusion is 
 more overwhelming in the vastness of all it offers for con- 
 sideration than this concerning the origin and history 
 of mineral fuel. No one can for a moment doubt that 
 the rocks containing coal abound with indications of 
 plants, and that they were originally deposits formed 
 in the vicinity of land. No one, again, who has looked 
 closely into the matter has ever ventured to suggest that 
 true coal can have had any other than a vegetable origin. 
 The nature of the vegetation is indicated by numberless 
 examples, and the coal appears to have been derived, 
 partly or chiefly, from the trunks of the trees of which 
 we have the fossil leaves. But the change that has taken 
 place to convert wood or other vegetation into coal has 
 never yet been imitated in human laboratories, and its 
 nature can only be guessed at. The accumulated heaps 
 of sand now converted into sandstone and lying over the 
 coal are sometimes penetrated for many yards by the 
 trunk of some ancient tree, also changed into stone and 
 yet no one can decide absolutely whether such accumula- 
 
ANCIENT FORESTS AND MODERN FUEL. 237 
 
 tions of sand were rapid or slow. Among the shales 
 that alternate with the sandstones are numerous and 
 valuable deposits of iron- ore, whose origin is not less ob- 
 scure than the conversion of wood into coal, but which 
 certainly were not what they now are when the beds 
 were deposited ; for many of the oval nodules of rich ore 
 are formed on some small fragment of a fern, or exhibit 
 a fruit of some tree in their centre. All these changes 
 seem to tend to the one great result, an accumulation of 
 mineral treasure into one spot which had been previously 
 distributed irregularly through a large space, a double 
 concentration of mineral wealth in two forms most useful 
 to man. 
 
 Thus, ancient forests, distributed over groups of islands 
 in the Northern hemisphere, have here and there, by 
 some happy accident, escaped from natural decay and 
 have become buried with mud and sand. The cause, 
 whatever it may have been, that first preserved the woody 
 and leafy matter from decay continued to act at the sur- 
 face, repeating its effect on each successive deposit that 
 came under its influence, while those heaps already com- 
 pleted passed downwards to greater depth, perhaps by 
 the slow collapse of some vast subterranean cavern. The 
 climatal cause that produced the coarse and rapid vege- 
 tation did not cease for a long period, and the forests 
 grew and were destroyed time after time, the whole after 
 each destruction being sealed up by overlying heaps of 
 sand and clay till the uppermost deposit lay some thou- 
 sand feet over that first formed. The buried vegetation 
 was squeezed by the vast pressure of all this overlying 
 mass, and afterwards by the load of hundreds of fathoms 
 
238 THE PICTURES TN THE BOOK. 
 
 of water. Other deposits succeeded, other climates pre- 
 vailed ; there were great changes among the inhabitants 
 of the globe; even the trees and shrubs were altered, and 
 the zamia took the place of the tree-fern, to be in its 
 turn succeeded by the present Northern vegetation. All 
 this time the buried forests were ripening into coal. 
 Century after century the slow change went on : the 
 woody fibre became lost, the cell-structure of the fibre 
 decayed; the water, unable entirely to escape, was re- 
 solved into its elements, and these entered into new 
 combinations, carburetted hydrogen being formed under 
 great pressure, and remaining pent up within the minute 
 interstices of the newly-formed mineral. 
 
 Of the millions of square miles of land forming the 
 islands of the ancient archipelago, a few thousands are 
 now covered with coal. Buried beneath hundreds of 
 yards of earth, and for the most part out of sight, this 
 mineral is eagerly sought for, and its value everywhere 
 recognized. North America, both the Northern States of 
 the Union and the British possessions, contains large de- 
 posits easily accessible. Great Britain has numerous de- 
 posits, far smaller, but of excellent quality; and these 
 also are, for the most part, readily obtained, though at 
 some cost. Belgium, Northern France, and Western 
 Germany have each small slices of the same valuable 
 material. In Southern France and Spain, in Russia and 
 Hungary, and in many other parts of Europe, there is 
 also coal. In various parts of Asia, in South Africa, in 
 Australia, and in some of the islands adjacent, patches 
 occur so similar in all essential points that they seem due 
 to similar causes. In the Tropics ; as well as in temperate 
 
ANCIENT FORESTS AND MODERN FUEL. 239 
 
 latitudes, and within the Arctic Circle, in the south as 
 well as in the north, mineral fuel, associated with fossil 
 vegetation, has therefore been found ; and there is every- 
 where a remarkable uniformity in the conditions under 
 which the two are present. The unused forest- trees of 
 old times have been converted into fuel for our benefit. 
 There are large stores of it; but these stores are not in- 
 exhaustible, nor are they capable of renovation. The 
 modern forests once cut down will, if properly managed, 
 become replaced within a century; but the coal once 
 gone is gone forever. On the other hand, the same work 
 may be going on partly at the mouths of our great rivers, 
 and partly where deposits of various geological age are 
 buried beneath the surface of earth and sea and are re- 
 moved far away out of our sight. 
 
fyt Jmtrimtffr, 
 
 THE PRE-ADAMITE WORLD. 
 
 Now comes another very curious question for our con- 
 sideration; and it is one that involves some difficulties 
 not yet alluded to. Like other difficulties, these must 
 be fairly and honestly met; for we may be quite sure that 
 it is only in this way that they can be conquered and got 
 rid of. They shall first be stated in as few words as pos- 
 sible, and then we will go on to consider how far they 
 affect us in understanding the geological problem. 
 
 In the first place, with regard to man. We are bound 
 to suppose that when a work of art the shaping of a 
 flint into the form of a weapon is discovered, it indi- 
 cates the presence of man in the place at some time or 
 other. If such an object is found in a cavern, buried 
 with bones, covered up with a coat of limestone, and that 
 covering again covered with gravel and other bones, all 
 indicating a gradual accumulation, we should be bound 
 to suppose that the place has had an earlier race of in- 
 habitants than that whose remains are found at the top, 
 and that this earlier race has been displaced. It is clear 
 that the more multiplied such specimens are, the greater 
 would be the probability of there having been a large 
 colony of the early inhabitants. If, too, these sculptured 
 flints are generally alike over a wide district, we might 
 240 
 
THE PRE-ADAMITE WORLD. 241 
 
 fairly presume that they had been made by a race ori- 
 ginally widely spread. 
 
 If, again, buried with stone weapons, which carry 
 back the date of the introduction of man to a distant 
 day, there are found the skeletons or other remains of 
 animals of various kinds now quite unknown, and if all 
 these, or many of them, have been preserved without 
 much injury to the most delicate angles of bone, and in 
 such numbers and variety as to make it clear that their 
 presence is not the result of local accident, we must 
 admit that these extinct races were contemporaneous with 
 the ancient human inhabitants. It is well known that 
 in Polar seas there have been found, frozen into mud- 
 cliffs, the complete carcasses of elephants adapted to a 
 cold climate by a coat of warm hair, and that these 
 carcasses occupy positions many hundred miles removed 
 from the nearest country which could now be their per- 
 manent home. There is thus independent proof that not 
 only the climate, but the larger quadrupeds, of import- 
 ant districts have greatly changed; and, though no 
 carcasses of men have been dug out of these cliffs, there 
 is little doubt that men lived at this period, and peopled 
 the countries of the north temperate zone. Very long, 
 therefore, before civilized races of men inhabited the 
 world, Geology has proved that the earth was tenanted 
 by an ample population, very different from existing 
 races, although, no doubt, well adapted to the climate 
 and conditions of existence of the time. Very long 
 indeed before even the faintest traces of human remains 
 have been suspected, there were other altogether differ- 1 
 ent groups of living things. No records appear of these 
 21 
 
242 THE PICTURES IN THE BOOK. 
 
 in any written book; but they are objects not without 
 ample illustration in that great stone record preserved 
 for our investigation in the rocks, mountains, and plains. 
 We find here all that is needed to reproduce the original. 
 The portrait is veiled, no doubt; but the main outlines 
 may be withdrawn from concealment. We are enabled 
 to bring together and compare the bones, the teeth, the 
 horny skin, the shell, or other parts of animals that have 
 been long buried; and afterwards, with such knowledge 
 as we possess, we may compare these with corresponding 
 parts of living and familiar animals, and arrive at definite 
 conclusions concerning them. 
 
 It is no easy task, this that we have here pointed out, 
 and it has required the combined knowledge and in- 
 genuity of many great and learned students of Nature 
 to come to a decision on disputed points. For centu- 
 ries men studied, and examined, and described, and with 
 difficulty became familiar with Nature's doings with ex- 
 isting races. Certain peculiarities of structure were 
 found to correspond with modes of life, with the food, 
 the method of obtaining food, and other matters. Thus, 
 a particular form and structure of tooth is known to be 
 adapted to a particular kind of food. The stomach, also, 
 must correspond to the teeth, in order that the food may 
 be digested ; the head and extremities must be adapted 
 so as to obtain it, and the remainder of the skeleton 
 must also be in exact accordance : so that there is a cer- 
 tain mutual fitness of all parts, by means of which any 
 one important bone or part of the skeleton ought to be 
 sufficient to enable us to describe and picture the whole 
 animal. 
 
THE PRE-ADAMITE WORLD. 243 
 
 And it is not only thus in the case of quadrupeds, 
 some of whom are strong and fierce, some weak and 
 gentle. The bird has a peculiar structure of bone, 
 having reference to its power of flight ; the fish has 
 another and totally different structure, enabling it to 
 remain always, and without effort, floating in the water. 
 The shell of the oyster or the lobster offers marked pecu- 
 liarities of structure. Some animals swim with their 
 shell, some float with it; some rest always on the bottom, 
 some burrow in the mud. In every case, the shell, like 
 the bone, is adapted to the use required of it, and has 
 a corresponding structure; and, indeed, each part of 
 every group of animals appears to have some peculiarity, 
 and a special arrangement and contrivance of its own, 
 enabling it to do its work in the fittest way, and allowing 
 it to be identified even if only a very small part of the 
 whole animal is present. 
 
 When, therefore, a bone or a shell is found, and is 
 shown to a competent naturalist, a person whose study 
 it is to find out and describe these mutual relations, he 
 is often able to tell at once to what animal it belonged, 
 and even a good deal about the individual peculiarities 
 of the animal itself. If a tooth, the form of the tooth 
 will at once tell an important tale : it was meant to cut 
 and tear, and therefore belonged to a flesh-eating, fierce 
 animal; or it was meant to grind, and belonged to an 
 herbivorous animal; or it could both cut and grind, and 
 belonged to an omnivorous brute. And then its struc- 
 ture : under a powerful microscope, the law of its forma- 
 tion, the relation it bears to other teeth of the same or 
 other animals, its mode of growth, and a hundred facts 
 
244 THE PICTURES IN THE BOOK. 
 
 of its history, are revealed. The state of the tooth will 
 indicate the amount of work it has done; its fangs and 
 shape will tell from what part of the jaws it came; and, 
 by a succession of inferences, we shall learn, at last, what 
 particular species, or at least what natural group, it may be 
 referred to. Of course, some teeth are more easily recog- 
 nized than others. The elephant's tooth is known by its 
 size, as well as by its peculiar arrangement of hard and 
 soft plates of bone and enamel; the shark's, by its shape, 
 and combination of saw and shears; the crocodile's, by 
 its mode of growth; and so on. In the hands of the 
 comparative anatomist, Nature may be interrogated till 
 she replies with complete accuracy; and if there is any 
 living species known to the inquirer to which the tooth 
 that is examined had belonged, to that species the tooth 
 will, in most cases, be referred. 
 
 But if there is no such species known, are we to con- 
 clude that the naturalist is at fault, and that he must 
 look yet more minutely at existing creation to discover a 
 species before unknown ? Doubtless, we are still igno- 
 rant of many facts in natural history, and new species are 
 being daily brought in from various quarters, so that the 
 mere fact of want of identity with a known species is not 
 sufficient to remove an undetermined animal from the 
 world of to-day. Should we, however, find that the re- 
 mains of animals buried in the earth, in any country, 
 indicate species not only quite unknown, but more nearly 
 allied to some not now found in the country in question, 
 when, for example, we pick up, and hand in for examina- 
 tion, numerous bones of the elephant, the rhinoceros, and 
 the hippopotamus, found in such beds of gravel as are 
 
THE PRE-ADAMITE WORLD. 245 
 
 common in many parts of England, or in caverns in the 
 limestone of Wales, Yorkshire, or Somersetshire, the 
 case is different. We know pretty well the existing 
 species of these large animals, and it is barely possible 
 that important varieties of them can exist anywhere, 
 either in Central Africa or the Asiatic islands; but that 
 any can hereafter be found which now live, in a wild 
 state, in northern temperate climates, and especially in 
 the smaller islands in our latitudes, is a simple impossi- 
 bility. The same is the case with the larger and fiercer 
 carnivora, or flesh-eating animals; and yet the bones of 
 large bears and hyenas are tolerably abundant in certain 
 places throughout Western and Northern Europe. 
 
 The species of these animals known only by their fossil 
 bones differ a good deal from the familiar and recent 
 kinds; and thus we are led to the first great difficulty 
 with regard to fossils, namely, that they represent and illus- 
 trate a natural history of the past, not consisting merely 
 of fragments of creatures recently living on the spot, nor 
 even of bones of such as are still met with at no great 
 distance in wilder parts of the country where man has 
 not the upper hand. They belong to species once living 
 and abundant in the very spots where their remains alone 
 now occur. They are, therefore, extinct species. 
 
 Now, it does not follow that animals and races are 
 everywhere absent or really extinct merely because they 
 are gone from countries they once inhabited. No doubt 
 the wolf, the wild boar, the black bear, the beaver, the 
 wild cat, and other animals, have departed from England 
 and become locally extinct; and so long as the land re- 
 mains cultivated and crowded with men they will never 
 21* 
 
246 THE PICTURES IN THE BOOK. 
 
 reappear. But they are only removed to a short distance, 
 and it will probably be very long before they are driven 
 out of their holds in the wilder and less-peopled parts of 
 the continent of Europe. It is not so with the elephant 
 and hippopotamus, the rhinoceros, the great cavern bear, 
 the great hyena, the gigantic large-horned deer, and 
 many other animals, whose bones are very common in 
 almost every bed of gravel, and in caverns. It is as 
 certain that the fossil species of these are extinct as that 
 the African and Asiatic elephants, the Polar and the 
 black bear, the hyena of the Cape and that of Abyssinia, 
 are essentially different the one from the other. 
 
 We thus learn the first lesson concerning organic re- 
 mains. They form the earliest chapter in the history of 
 the pre- Adamite world, the world where men were not, 
 and when the lower natures reigned. And just as in 
 each country now there is a group of animals a large 
 number of which may range widely, while others are 
 strictly confined within narrow limits of space, so in the 
 old times each district had its own group of species now 
 lost. And so, also, in all the successive deposits made at 
 different times, there have been at every period natural 
 groups, some of species ranging widely in time, some 
 spreading over large areas, and others almost confined to 
 one bed, or to one brief period of time. A due con- 
 sideration of this very important fact will clear up 
 much that appears incomprehensible in Geology, and 
 will enable the reader to understand how, by the study 
 of the natural group of organic remains or fossils of any 
 district, a knowledge may be obtained as to its relative 
 
THE PRE-ADAMITE WORLD. 247 
 
 age, and its place in the great series of stratified fossili- 
 ferous rocks. 
 
 A long expression is this, the series of stratified fos- 
 siliferous rocks, and a great stumbling-block to many a 
 young geologist. -But it has a real and important mean- 
 ing, and, when clearly felt as well as understood, is a 
 wonderful help to the struggling student. 
 
 Let us endeavor to illustrate the matter, as we have 
 done more than once before, by a kind of mechanical 
 diagram. Suppose a heap of books, most of them illus- 
 trated, and all written in languages concerning which we 
 are either imperfectly instructed or altogether ignorant. 
 These books, thrown confusedly on a table, may represent 
 a number of deposits of various kinds of rock containing 
 fossils. The fossils are represented by the pictures in 
 the books, and the books, piled in some irregular order, 
 now represent the series of stratified fossiliferous rocks. 
 To identify the books under such circumstances, it will 
 clearly be necessary to examine and compare the pictures. 
 They alone will teach us the state of knowledge of the 
 people, and the object of the work illustrated, and we 
 might infer from them the relative dates of the various 
 books. In some cases we may find the illustrations nu- 
 merous, clear, systematic, and highly characteristic; in 
 others they are few, expressed in mere outline, difficult 
 to make out, and comparatively uninteresting. On the 
 whole, they may, perhaps, give us an idea of the prevail- 
 ing tone of the collection of books; and what knowledge 
 we thus obtain is valuable and trustworthy. It must be 
 remembered, however, that with regard to the rocks we 
 have only lately begun to look for these illustrations. 
 
248 THE PICTURES IN THE BOOK. 
 
 Many of them have been turned over by our forefathers 
 without notice or allusion ; out of the whole number act- 
 ually there we have seen but a small proportion, and did 
 we know all we should still only have glimpses of a com- 
 plete history. An earnest conviction of this " imperfec- 
 tion of the geologic record" is, perhaps, one of the safest 
 feelings that can be cultivated by those who attempt to 
 question Nature on this subject of fossils. 
 
 At the same time, it is quite as important that the true 
 and great value'and accuracy of the knowledge thus ob- 
 tained, and the rapidity of its growth, should give con- 
 fidence and hopefulness. We may not hope to attain to 
 perfect acquaintance with Nature's scheme, or fathom the 
 infinite depth of her ways. Unbounded wealth of know- 
 ledge exists, no doubt, in every department, and much of 
 this wealth we may expect to acquire in the course of 
 time; but let no one suppose that he has exhausted the 
 store, or that others who succeed him may not find even 
 more than himself, assisted as they ought to be by his 
 researches, and enlightened by what he and his fellow- 
 laborers have made clear. 
 
 In every department of Natural History, the number 
 and variety of extinct animals determined only by frag- 
 ments found fossil is already large and exceedingly im- 
 portant. Even with regard to man himself, although, as 
 we have said, no bones have yet been detected, there is 
 good evidence of a long history and association with 
 ancient and lost races, in the flint weapons, cut to a uni- 
 form pattern, lately found in gravel and caverns. Of the 
 large quadrupeds, the variety is considerable; and such 
 animals, being prominent and familiarly known, naturally 
 
THE PRE-ADAMITE WORLD. 249 
 
 attract attention. Their remains are most abundant in 
 the newest deposits; and, indeed, it is not likely that com- 
 plete remains of large animals will ever be met with in 
 the earlier rocks, deposited when land probably existed in 
 much smaller proportion than at present in our latitudes. 
 The elephants, mastodons, and other great quadrupeds of 
 similar bulk and structure, have left behind them nume- 
 rous teeth, and bones, and tusks, in most parts of Europe, 
 in the various surface-beds, chiefly of gravel and mud; 
 and for the most part the extinct species differed from 
 existing kinds more in proportions than actual size. 
 Thus, the American elephant (Mastodon) had peculiar 
 teeth, very different in appearance from those of the 
 Asiatic or African, but serving similar purpose. The 
 animal was also longer in the body, and not so tall. The 
 Asiatic elephant of former times resembled the Asiatic 
 species at present living, but was larger, and had tusks 
 of the most portentous length. A minute species of ele- 
 phant has recently been discovered in Malta. Extinct 
 hippopotami are found in India, varying in size from an 
 elephant to a pig ; and there are several varieties of ex- 
 tinct rhinoceroses showing extreme difference of dimen- 
 sions. 
 
 While, however, the elephantine animals in the gravel 
 were thus equal or superior in size as well as variety to 
 those of Asia, the corresponding animals in the clay-beds 
 near London, of much more ancient date, are more varied 
 in form, and very much smaller. Few of them exceeded 
 in size the American tapir, and they seem to have been 
 adapted to live in swampy districts or in water. Still, 
 even here there are exceptions; for a few imperfect speci- 
 
250 THE PICTURES IN THE BOOK. 
 
 meris have shown that there was with these, in similar 
 deposits, one animal at least double the size of the tapir, 
 and therefore approaching in that respect the smaller 
 elephants. 
 
 The Mammoth, the elephant of Siberia, whose car- 
 cass was found in its integrity, at the beginning of this 
 century, walled up in the frozen banks of a river, in 
 latitude 70 N. was by no means the most ancient of its 
 race. Several species are known to have preceded it and 
 had long cease'd to live before it nourished. 
 
 Some very singular extinct animals are known, which 
 form links between living species now widely separate. 
 Who would anticipate the existence of a creature with 
 the trunk and general proportions of an elephant, but 
 whose head was decorated with four horns, two like those 
 of the ox and two like those of the antelope? Such 
 was the Sivathere., living in India at a time when a great 
 lake extended south of the Himalayas, in the present 
 Valley of the Ganges. At the same time, and in the 
 same place, there existed a curious combination of the 
 horse and rhinoceros, and numerous giraffes, animals now 
 confined to the interior of Africa. 
 
 Other remarkable instances there are of gigantic ie- 
 presentutives of existing quadrupeds. Some of these are 
 very striking. Thus, in South America where we have 
 now a peculiar group of animals, illustrated by the sloth 
 and the armadillo, both of small size the extinct 
 species, of no very ancient date, include the Megatherium 
 and Mylodon, sloths larger and much more cumbrous 
 than the elephant, and apparently adapted to serve the 
 same purpose in keeping down tree-vegetation. These 
 
THE PRE-ADAMITE WORLD. 251 
 
 creatures, not being able to climb trees, pulled them 
 down and then fed on them. So also the Glyptodon, of" 
 the same part of the world, was an armadillo multiplied 
 into an animal ten feet long, coated with bony armor 
 some inches thick ; and the MacraucJienia was an almost 
 equally expanded llama. Australia presents a similar 
 condition of existence, the extinct kangaroos of that 
 country having been as large as the megatherium, and 
 the wombats as large as the tapir. These were accom- 
 panied by a carnivorous quadruped, rivalling the lion in 
 size, but marsupial in its habits, like all the quadrupeds 
 of that remarkable country, in former times as well as 
 now. 
 
 Very large animals, nearly allied to the lion and tiger, 
 seem to have extended over the Northern hemisphere at 
 a period not geologically remote, since their bones are 
 found in the gravel and other surface-deposits; and at 
 the same time, as all the principal natural groups of ani- 
 mals seem to have been ever limited geographically, we 
 may conclude that the present great divisions of land and 
 water were more than indicated. It is rarely, except in 
 Australia, that we find extinct marsupials, rarely, ex- 
 cept in South America, that we have bones of extinct 
 Edentates] while Asia, at the time we refer to, was just 
 as remarkable for its pachyderms and ruminants as it is 
 at present. Only at that time Asia belonged to Europe, 
 in its zoological relations, much more than it does now, 
 and even the African hyenas and hippopotami over- 
 spread the northwestern land. Bears of gigantic size 
 were common; a curious gigantic deer, not unlike the 
 reindeer, but larger, with horns spreading to enormous 
 
252 THE PICTURES IN THE BOOK. 
 
 width, ranged over our own islands and the continent 
 adjacent, and was accompanied by other deer, some still 
 remaining in Northern Europe, but most of them lost 
 forever. 
 
 When we pass on to consider the quadrupeds of still 
 older rocks, we must be prepared for a great change. 
 The illustrations pictured in the Stone Record are few, 
 and belong to very small kinds; but whether this small 
 size, and the curious marsupial structure indicated by the 
 skeleton, really- mean that nothing more existed at that 
 time, or whether the land in our neighborhood consisted 
 only of small and detached islands instead of large con- 
 tinents, it would not be safe to assert. Certain it is that 
 groups of small islands in an open sea are still without 
 quadrupeds larger than a rat; and there would seem no 
 reason why this should not account for the absence of 
 fossils, without having recourse to the assumption that 
 no larger kinds had been created. 
 
 Birds tell the same tale as quadrupeds in all essential 
 points. Their bones being for the most part small and 
 delicate, and the greater number of them living quite in 
 the interior of land, it could hardly be that many of 
 their remains would be found among the fossils. Still, 
 as a considerable group inhabit near the shore, and are 
 frequently flying over the sea, there is nothing improba- 
 ble in their being preserved. There are, in fact, abun- 
 dant proofs of their existence, even in rocks very low in 
 the great series, although the actual remains found in 
 such localities are few and unsatisfactory. But there is 
 one very curious fact regarding birds. Though usually 
 adapted for flight, there are some species confined to the 
 
THE PRE-ADAMITE WORLD. 253 
 
 land, and these are more or less nearly deprived of wings. 
 Just as, in Australia, there are a number of extinct but 
 gigantic marsupial quadrupeds, so in the islands of New 
 Zealand, not far off, there are numerous remains of 
 gigantic wingless birds, represented at present by smaller 
 wingless birds of very similar habits. In both cases the 
 number and variety of the extinct species is consider- 
 able, and the giants must have continued very nearly 
 to our own times. 
 
 Besides the bones of birds, their footprints are some- 
 times retained when they have walked over mud in a 
 state favorable for preserving markings made upon it. 
 "We thus learn that in very ancient, if not the oldest, 
 periods of our earth's history, birds of gigantic dimen- 
 sions, and many of smaller size, have lived in Europe 
 and in North America, or rather, perhaps, in islands in 
 a northern archipelago, whose shores, after many alter- 
 nations, after being buried deep under water and lifted 
 high into air, have at last settled for the present into 
 the sandstones of Cheshire and Warwickshire and cor- 
 responding beds in Germany and North America. 
 
 Reptiles are, in their mode of living, intermediate be- 
 tween quadrupeds and fishes. Cold-blooded, or, in other 
 words, needing only a slow aeration of the blood, they 
 can exist for some time without taking in fresh breath ; 
 and some of them are so contrived as to breathe, as fishes 
 do, by exposing the blood to aerated water in gills. 
 There are many varieties of reptiles still living; their 
 habits and ways of living are distinct from those of 
 higher animals, and they include inhabitants of land and 
 water. 
 
 22 
 
254 TH3 PICTURES IN THE BOOK. 
 
 Extinct reptiles are exceedingly numerous, and include 
 varieties quite unknown in the living state. Thus, there 
 are flying species found fossil, and there are also some 
 adapted to reside permanently in the sea. Others again 
 there are exceedingly remarkable in structure, and very 
 characteristic of certain volumes of the Stone Library. 
 
 Of all the extinct reptiles, perhaps the most different 
 from any animal now living were the lofty giants of the 
 forest and tenants of the air : the latter, indeed, vampire- 
 like, darkened the sky with their wide outspread wings. 
 Some of the former were not only as bulky as the ele- 
 phant, although with a more elongated body and a croco- 
 dilian head, but they stood erect on legs far higher in 
 proportion than those of any existing reptile. We are 
 in the habit of regarding all reptiles as creeping, or 
 moving with the body almost touching the ground ; but 
 in these creatures we have some varieties, of portentous 
 bulk, walking over the earth like veritable lords of crea- 
 tion, some feeding on trees, and others preying on the 
 smaller reptiles and other animals of their time. Asso- 
 ciated with them were crocodiles, and probably lizards, 
 like those still living. 
 
 But these singular and eccentric, perhaps repulsive, 
 animals, which seem to have been the principal inhabit- 
 ants of the land of their time, are neither the oldest, 
 nor are they the most curiously strange, examples of 
 creative power in this department of the animal kingdom. 
 During the deposit of the beds of sandstone now quar- 
 ried at Liverpool, there lived on the land then existing 
 in the neighborhood a varied group of gigantic frog-like 
 reptiles, whose fore limbs were small, but the hinder 
 
THE PRE-ADAM1TE WORLD. 255 
 
 paws of such dimensions as to leave prints in the sand 
 occupying nearly a square foot of surface each. The 
 head was large, broad, and flat, and almost like that of 
 the crocodile, but intermediate between it and the frog. 
 Probably about the same time, in the opposite hemi- 
 sphere, there were creatures nearly as large, approaching 
 the turtles more than the frogs in their structure, but 
 real quadrupeds, walkers, that is, on four equal legs, 
 and true reptiles, but by no means creeping things. 
 
 It must not be supposed that because in this outline 
 mention is made only of the more singular and less fami- 
 liar forms, there were no others living, and no repetition, 
 under various conditions, of the general types of struc- 
 ture. Very few fossils are found in those sandstones in 
 which have been retained the footprints that are so re- 
 markable; but other footprints, both of smaller lizard-like 
 reptiles and of birds, are there very common. Some of 
 these markings may have belonged to small quadrupeds ; 
 for we know there were some such animals in the rocks 
 containing bones of the gigantic land-reptiles. The 
 illustrations that teach us the nature of land-animals 
 are very obscure and very few in number, and we must 
 not judge of Nature by the amount of evidence hitherto 
 collected in this inquiry. 
 
 At a comparatively early period in the earth's history, 
 reptiles inhabited the air like birds, some of them only 
 occasionally, perhaps, touching the earth. The bones of 
 such creatures, as we have said, indicate dimensions of 
 the largest size, as compared with winged birds adapted 
 for flight. The greatest width across the expanded wing- 
 membrane, from tip to tip, amounts, in some cases, to 
 
256 THE PICTURES IN THE BOOK. 
 
 more than twenty feet, and the head was exceedingly 
 large and long in proportion to the body. No remains 
 of these creatures have been found in the sandstones 
 with the footmarks just alluded to; but they are common 
 in all newer deposits as far as the chalk. They seem to 
 have been able to swim, and perhaps to dive; and they 
 were certainly reptiles of prey. 
 
 In addition to the land and air species, we also find 
 fossil a considerable and interesting group of marine 
 reptiles. These, too, were some of them very gigantic, 
 approaching even the whales in this respect, while there 
 is every probability that they were much more fierce. 
 Unlike the ordinary hard coat of mail that we find cover- 
 ing most known reptiles, and that appears also to have 
 belonged to those in a fossil state, the marine species were 
 soft-skinned, and exhibit strength rather for attack than 
 defence. There are two principal groups, one approach- 
 ing much more nearly to the true fishes than the other. 
 The one well known as the Ichthyosaur, or fish-lizard, has 
 been handed down to us in unusual perfection, many com- 
 plete skeletons having been worked out of their stony 
 beds, and numerous indications given even of the skin 
 and the contents of the stomach. 
 
 The Plesiosaur, although more nearly a lizard, as its 
 name implies, would seem to have been even less like any 
 existing animal than its companion. It has been com- 
 pared to a serpent in a turtle's shell; but in truth, though 
 the neck was exceedingly long and the head that of 
 a lizard, the body was smooth and naked, the tail not 
 very long, and the extremities like the paddles of a 
 whale. Some of the specimens seem to indicate an ani- 
 
THE PRE-ADAMITE WORLD. 257 
 
 mal as much as thirty feet long, and the entire and undis- 
 turbed skeletons of many individuals, of various sizes 
 and different proportions, are to be found in museums. 
 
 At present almost all the common fishes are provided 
 with moderately hard complete skeletons, and are covered 
 with scales usually small and thin. Most of the fish 
 whose remains are found fossil are, however, remarkable 
 for having had cartilaginous instead of bony skeletons. 
 They were enclosed in a bony box, coated with enamel, 
 by means of which the whole animal was defended against 
 powerful enemies. Few fishes of this kind have been 
 found in modern waters; but the "bony pike" of the 
 North American lakes and rivers is a fair illustration of 
 these knights of ancient times. The fishes whose re- 
 mains are found fossil offer nothing remarkable in regard 
 to size, many existing species being larger than any 
 known extinct kinds. But in strangeness of form, 
 among those enclosed in a coat of mail, the oldest 
 species have hardly since been rivalled. The bony plates 
 are very large, and their shapes such as accurately to 
 adapt them to enclose the small body of the animal 
 between back-plate and breast-plate. One kind, called 
 Pterichthys (the wing-fish), had strong spines, like arms, 
 placed near the head, and a very curious tail, tapering 
 and flattened, almost like that of a beaver. The head 
 was defended by a kind of helmet joining on to the back. 
 
 Exceedingly abundant in the old rocks, these fishes 
 seem gradually to have become fewer and less important, 
 being replaced latterly by the scale-covered fish of modern 
 times. Sharks and Rays, however, seem always to have 
 existed, and were generally common. They left behind 
 
 22* 
 
258 THE PICTURES IN THE BOOK. 
 
 them not only teeth, but bony and enamelled spines, and 
 even scales, these being more permanent than modern 
 scales, though often quite detached, and never connecting 
 into complete armor. 
 
 There are several curious animals now living, large and 
 strong enough to prey even upon fish, but belonging to a 
 group whose nervous structure places them in a lower posi- 
 tion in the series of animals. The cuttle-fish, of which 
 there are many kinds round our own shores and in the 
 Mediterranean, often attain a very large size. Some of 
 them possess, when living, a curious oval flattened plate, 
 called (not very improperly) "the bone," which is con- 
 stantly found washed up on the sea-shore, quite detached 
 from the animal. Many of them have a black fluid, 
 which they are able to throw out and thereby darken the 
 water when they wish either to escape or confuse their 
 prey. 
 
 The Nautilus occupies a shell divided into many small 
 compartments, each of which is pierced with a hole of 
 moderate size, and all of which are crossed by a tube. 
 The animal belonging to this shell is a kind of cuttle- 
 fish, and the whole shell serves as a float to the creature, 
 which inhabits only the outermost chamber, the rest 
 being full of air. 
 
 It is not a little interesting to find that, of animals 
 covered with shells, these cuttle-fish seem to have been 
 at all times the most characteristic. They have perhaps 
 been more readily preserved than others, owing to various 
 causes; but, at any rate, it is certain that, in the older 
 rocks, shells built upon a principle almost the same as 
 that of the nautilus are so incredibly abundant and so 
 
THE PRE-ADAMITE WORLD. 259 
 
 wonderfully varied as to make it certain that their 
 owners played a very important part in their day. 
 Whether they were accompanied by the commoner kind 
 of shells, which have not been preserved, or whether the 
 conditions of deposit were unfavorable for these latter, we 
 cannot now tell. The geological record is imperfect. The 
 illustrations of particular kinds of animals are numerous 
 and minute, while there are few indications of the ex- 
 istence of the others. The Ammonites of geologists in- 
 clude a wonderful variety of curious shells, nearly re- 
 sembling the nautilus in having a multitude of chambers. 
 They have been found of all sizes, from a coach-wheel 
 down to a pin's head; and where the ordinary forms are 
 absent, there are other shells evidently of the same kind, 
 and differing only in matters of detail. So also the 
 Belemnite, the hard part or bone of another extinct 
 species of cuttle-fish, though very different from the 
 corresponding part of known living specimens, evidently 
 answered a similar purpose. It is therefore clear that 
 these curious and, for the most part, powerful represent- 
 atives of a class of animals which we now think very 
 little of, and of which we speak slightingly, identifying 
 them with the snails, oysters, and limpets, really at one 
 time played a part hardly subordinate to fishes, being 
 quite as active and perhaps almost as intelligent. Cer- 
 tainly no one now can watch them in the sea, and notice 
 their restless activity, their long arms covered with 
 suckers, their large bright eyes always on the look-out, 
 their powerful jaws, and perfect means of helping them- 
 selves and supplying every important want, without 
 
260 THE PICTURES IN THE BOOK. 
 
 feeling satisfied that they are well able to perform their 
 part in Nature. 
 
 Shells, being very easily preserved among the sand 
 and other material at the bottom of the sea or near a 
 shore, are naturally among the most common of all 
 Organic Remains. They also, and for the same reason, 
 speak most distinctly as to the fact that the animals now 
 living on our shores and in the sea are either not the 
 actual descendants of the former inhabitants, or, if they 
 are, are so much altered by time and circumstance as 
 not to show any family resemblance. They resemble 
 each other, in fact, only in the way that the shells of the 
 British shores resemble those of the Indian Archipelago. 
 Both series evidently served the same purpose, that of 
 sheltering the animal; but they are provided with differ- 
 ent contrivances, and are often built up in a different 
 manner, because the circumstances of existence are ex- 
 ceedingly distinct. 
 
 Each group of deposits presents its own group of 
 shells, just as each principal district of the earth has its 
 characteristic species. In each case a few of the species 
 range very widely; but the bulk are possessed of some 
 marked peculiarities, and cannot be removed without 
 either losing these or dying. 
 
 What we have here said of shells applies equally well 
 to all other animals, and even to all vegetable produc- 
 tions ; and in proportion as they range widely now over 
 the earth's surface, so do they seem to have extended 
 far back in time, while the kinds that are limited in 
 space are very local. The variety of forms in these lower 
 animals is now very great, and has been in old time much 
 
THE PRE-ADAMITE WORLD. 261 
 
 greater; but still there are certain general principles and 
 laws that seem to have governed them always; and these 
 are so evidently related to the fitness of each created 
 being for the time and place of its existence, that we 
 learn to trust implicitly to such relations, and assume the 
 conditions of life from the animal, or the structure of 
 the living being from known conditions of existence, 
 without fearing the possibility of error. 
 
 When, then, we find in almost all deposits, whether of 
 limestone, sandstone, or clay, or any mixture of the three, 
 the remains of species of animals once inhabiting the sea, 
 preserved without injury, and often very plentiful, and 
 when we discover that each group of deposits is, on the 
 whole, characterized by some special assemblage of animal 
 or vegetable remains peculiar to itself, and nowhere ex- 
 actly repeated, though we must suppose similar states of 
 climate and temperature to have been often repeated, 
 geologists deduce one of those broad generalizations some- 
 times called Laws of Nature. The law thus discovered 
 being in perfect harmony with all that is now known of 
 the distribution of life, we may with greater reason accept 
 it and employ it in further inquiries. 
 
 From the study and application of this law, very large 
 and important natural-history results have been obtained. 
 Learning first by careful observation the various remains 
 most abundant and most characteristic of the different 
 deposits of one country, and working them into a regular 
 series, these have been compared with corresponding series 
 from another country adjacent. From this comparison, 
 bearing in mind the difference of mineral character, the 
 relative age of the two deposits has been determined - } and, 
 
262 THE PICTURES IN THE BOOK. 
 
 in some cases, independent evidence has confirmed the de- 
 cision thus made. With the peculiar fossils of a deposit are 
 always mixed up a number that are common to other de- 
 posits, above or below; but on the whole, as we have said, 
 there is a nucleus that, with a little attention and study, 
 may be recognized with much certainty. Stated in other 
 words, this means that fossils are characteristic of form- 
 ations. 
 
 It is a fact, settled by observation, that fossils may 
 safely be used to identify such deposits as were made in 
 various places nearly at the same time. In this way also 
 it has been found possible to prepare geological maps for 
 whole continents, that shall communicate a large amount 
 of truth and not much chance of serious error, the rela- 
 tive position of all principal beds being made out by the 
 comparison of the fossils found in them. 
 
 All kinds of fossils are useful for these purposes; but 
 it will necessarily happen that the remains most easily 
 recognized and least easily injured those most abundant 
 and most complete in themselves, and not the rarest or the 
 most abnormal will be the most generally useful. Thus, 
 sea-shells, star-fishes, sea-eggs, and sea-urchins, crabs and 
 other crustaceans, corals, and when the microscope is at 
 hand those minute specks, too small to be crushed and 
 too delicate to be destroyed, called Foraminifera, are all 
 extremely useful, and often far more so than strange and 
 quaint fishes, reptiles, birds, and quadrupeds. All these 
 are valuable when in sufficient abundance; but number 
 and variety are more important than size and unfamiliar 
 structure. 
 
 The pre- Adamite world includes, then, a long series of 
 
THE PRE-ADAMITE WORLD. 263 
 
 creations of beings, each series adapted to the exigencies 
 of its own day. If, as we suppose from the study of 
 fossils, there were once warm, swampy islands in these 
 latitudes, instead of a large continent, we might have in 
 our temperate zone a growth of tapirs, antelopes, and 
 other animals fitted for the climate, together with 
 monkeys, snakes, and vultures. If, on the contrary, the 
 ice reached far down from the Poles towards Southern 
 Europe, and the climate was less genial, there was a cor- 
 responding supply of bears and the larger quadrupeds, 
 adapted to exposure by warm coats of fur, and still 
 finding sufficient food in the twigs of trees. If, again, 
 there was deep water as now in the mid- Atlantic, abun- 
 dant supplies of minute foraminiferous shells like those 
 in the chalk covered the ocean-floor; while if the water 
 were more shallow, perchance the remains of sharks and 
 other strange marine creatures might be accumulated, 
 together with a rich harvest of shells and shoal-animals. 
 Or, lastly, if a river had emptied itself in the neighbor- 
 hood, there would be marks of fresh water and the 
 remains of land vegetation, insects, and land-animals alone, 
 or mixed with marine remains. All the peculiarities of de- 
 posit would be marked, and most of them could be dis- 
 covered, by the nature of the organic remains. 
 
 No one who has not examined for himself can conceive 
 the vast extent the incredible wealth and profusion of 
 Nature in this perpetual production of new forms and 
 structures from time to time, as circumstances have 
 changed throughout the world's history. Of all these a 
 multitude of examples, no doubt, remains ; but what are 
 they in proportion to the number that is lost ? We grope 
 
264 THE PICTURES IN THE BOOK. 
 
 about in the dark, picking up here a little and there a 
 little; but we can never hope to remove and bring to 
 light all that is left, and there must remain to the last, 
 in the great burying-place of Nature, a far larger series 
 than the most searching investigation of man will ever 
 bring to light. Could we even attain to a complete know- 
 ledge of organic remains, we should have made but one 
 step, and that an imperfect and incomplete step, towards 
 an acquaintance with the life that has passed away; for 
 there still must' remain large gaps to be supplied of such 
 animals as pass out of existence and leave no durable 
 skeleton or hard part capable of conservation. 
 
 We have already alluded to this subject in a previous 
 page as illustrating what has been well called " the im- 
 perfection of the geologic record." It is right that the 
 young geologist should know the exact nature and value 
 of the weapons and instruments put into his hand, and 
 for this purpose the limits of the evidence yielded by 
 fossils must be learnt, as well as the extent of that evi- 
 dence. There is amply sufficient positive knowledge to 
 occupy all our thoughts, and quite enough gaps left to 
 teach caution and humility. 
 
F&BT 
 
 . 
 
THE GREAT STONE BOOK 
 PART V. 
 
Chapter % Jifteijr. 
 
 GLITTERING TREASURES OF THE EARTH. 
 
 THE surface of the earth, the air, and the shores and 
 depths of the ocean, afford innumerable objects of beauty 
 and interest. But the earth also contains within its 
 bosom marvellous and beautiful things, belonging to that 
 kingdom of nature in which life plays no part, and pos- 
 sessing even a more tangible and direct value than the 
 others. The earth yields its rich treasures of minerals, 
 metals, and precious stones, serving as convenient repre- 
 sentatives of money and property; and these, when their 
 beauty of appearance in any way corresponds with the 
 difficulty of obtaining them, are objects of ambition to 
 great potentates, as well as the admiration of all classes, 
 including among their votaries the poet and the artist, 
 the man of science and the man of fashion, the most 
 civilized races and the uncultivated savage. 
 
 Of these objects, let us confine our attention here to 
 one group. Let us talk of gems, precious stones, and 
 jewels, leaving the metals, the many valuable minerals, 
 that are less sightly than gems, and the curious fossils, 
 buried records of former states of existence. Let us 
 consider those stones selected as ornaments of the crown, 
 the cabinet, and the toilet, the gems that glitter before 
 
 267 
 
268 THE TREASURES CONTAINED IN THE BOOK. 
 
 our eyes on gala-days, or are seen in museums and in the 
 shops of the jewellers. 
 
 There is great variety in the literature of gems. There 
 is the natural history, and what we may call the personal 
 history, the investigation of the optical properties, the 
 story of the mechanical preparation, of the commercial 
 use, and of the money value. There is the chemistry 
 and the geography, the science and the art, the religion 
 and the mysticism, of jewels : each might serve as the 
 heading of a chapter; but we will endeavor to give an 
 idea of the whole subject, without introducing systematic 
 divisions. 
 
 Of all gems the DIAMOND is the recognized queen, 
 the most beautiful, the most valuable, the most durable, 
 and the most useful; the hardest, though capable of 
 being split; the symbol of justice, innocence, constancy, 
 faith, and strength. According to a Jewish tradition, 
 the diamond in the breastplate of Aaron became dark 
 and dim when any person justly accused of a crime ap- 
 peared before him, and blazed more brightly when the 
 accusation was void of foundation. In the possession of 
 any one the diamond was supposed, in former times, to 
 mark the approach of poison by a damp exudation, and 
 to be a sure defence against plagues and sorcery. Taken 
 internally, it was believed to be itself a poison. 
 
 No history dates back to the period at which diamonds 
 were first discovered; but we are told on classical author- 
 ity that a boy, a native of Crete, bearing the name 
 afterwards given to this precious gem, was one of the 
 attendants of the infant Jupiter in his cradle. The other 
 attendants being promoted to be constellations, Diamond 
 
GLITTERING TREASURES OF THE EARTH. 269 
 
 was transformed into the hardest and most brilliant sub- 
 stance in nature. In Hindu mythology the diamond 
 plays an important part. 
 
 Diamonds are singularly associated with gold in the 
 earth, but all that come into the market as gems have 
 been obtained either from India or Brazil. The account 
 in the "Arabian Nights" of Sinbad the Sailor obtaining 
 diamonds by fishing for them with pieces of raw meat 
 is repeated as a fact of Indian statistics by the old Vene- 
 tian traveller Marco Polo. "The persons," he says, 
 "who are in quest of diamonds take their stand near the 
 mouth of a certain cavern, and from thence cast down 
 several pieces of flesh, which the eagles and storks pur- 
 sue into the valleys and carry off with them to the tops 
 of the rocks. Thither the men immediately ascend, and, 
 recovering the pieces of meat, frequently find diamonds 
 adhering to them." The more ordinary mode of obtain- 
 ing them at present is by washing away the earth and 
 stones from the gravel in which they are found. 
 
 The first Brazilian diamonds were discovered by acci- 
 dent just a century and a quarter ago. They also are 
 found in the surface-gravel, from which they are sepa- 
 rated by water in nearly the same manner as in India. 
 Upwards of seventy pounds' weight of these valuable 
 jewels were collected and brought over to Europe in one 
 year, shortly after the discovery of the deposit ; and it is 
 estimated that some two tons' weight, valued at sixteen 
 millions sterling, had been obtained from the South Ame- 
 rican mines up to the year 1850. So abundantly are 
 they there distributed that they have been picked up 
 with vegetable-roots in gardens, the stones in the roads 
 23* 
 
270 THE TREASURES CONTAINED IN THE BOOK. 
 
 have contained them, and the fowls have swallowed them 
 to assist digestion. 
 
 Marvellous as it may seem, diamond is but coal in a 
 crystalline form, and is hardly even so pure as some kinds 
 of anthracite, or stone coal, found in Wales. Like coal, 
 the diamond burns, or combines with oxygen, though 
 only at a very high temperature, and the whole substance 
 then disappears in carbonic acid gas. Unlike coal, how- 
 ever, diamonds are usually transparent, possessing a pecu- 
 liar lustre, hence called adamantine, and reflecting light 
 from their inner surface. The light entering a diamond 
 is bent more than in passing into any other substance in 
 nature. Diamond is electric, even when rough, and pos- 
 sesses phosphoric and luminous properties after being 
 exposed to the sun for some time. It is generally of 
 crystalline form, but coated over in the mine by a thick 
 crust, exceedingly hard. Still, even the children, in 
 countries where they abound, can generally detect the 
 valuable gems in their concealment. 
 
 Diamonds require very careful cutting, so as to dimi- 
 nish their weight as little as possible consistently with 
 insuring the greatest amount of internal reflecting sur- 
 face belonging to their form. Their value as gems depends 
 greatly on the cutting, and this, of course, to some ex- 
 tent, on the original shape. What are technically called 
 "brilliants" are those stones that can be cut without 
 serious loss into the form of two pyramids placed base to 
 base. Of these pyramids a slice of the one intended to 
 be presented to the eye is cut off, while the other, serving 
 to reflect light from its internal surface, although also 
 flattened slightly, is much the more nearly pointed of the 
 
GLITTERING TREASURES OF THE EARTH. 271 
 
 two. In fine brilliants the upper pyramid has thirty-two 
 facets, or sides, and the lower twenty-four. Nearly half 
 the diamond is often wasted in cutting a brilliant; but with- 
 out it a fine stone can hardly be considered as presenting 
 the real beauty that belongs to it. When, however, the 
 form of the stone is such as not readily to admit of this 
 treatment, only one pyramid is cut, and the base is im- 
 bedded in the setting, making what is called a rose dia- 
 mond. When there is a double pyramid, the setting 
 simply clasps the girdle, or junction of the bases of the 
 two pyramids, and the two sets of faces are both exposed 
 to the action of light. Besides these two kinds, some 
 diamonds are cut flat, with irregular facets: these are 
 called table diamonds, and their value, weight for weight, 
 is very inferior to that of roses and brilliants. 
 
 Diamond-cutting is a business in the hands of Jews, 
 and is chiefly carried on in Amsterdam, where, it is said, 
 ten thousand persons are more or less dependent on it as 
 an occupation. Owing to the extreme hardness of the 
 stone, the only means of acting on it are by rubbing two 
 faces of different diamonds together, or cutting the stone 
 by a circular steel saw covered with diamond dust. 
 
 Diamonds are not always colorless, though many of 
 those most highly valued are so. Some few that are 
 known of fair size and clear distinct tints are even more 
 costly than those of purest white. There is a difference 
 in the estimate of color. Thus, the celebrated blue dia- 
 mond of Mr. Hope, weighing one hundred and seventy- 
 seven grains, and the green diamond of the crown of 
 Saxony, the finest known colored specimens, are regarded 
 as more valuable than if they were white. The yellow 
 
272 THE TREASURES CONTAINED IN THE BOOK. 
 
 varieties, on the other hand, generally sell at lower prices 
 than stones of equal weight without color. 
 
 The largest diamond known is an uncut stone belong- 
 ing to the Rajah of Mattam, in Borneo. It weighs more 
 than two ounces and a quarter troy, but would probably 
 be very greatly reduced if properly cut. It is egg- 
 shaped, and indented at the smaller end. The largest 
 regularly cut diamond is a rose, and of yellowish tint: it 
 weighs one hundred and thirty-nine and a half carats,* or 
 nearly an ounce. The finest brilliant is the Pitt or Re- 
 gent diamond, now in the French crown. It originally 
 weighed four hundred and ten carats, but has been re- 
 duced to one hundred and thirty-seven by cutting, and 
 was sold to the Regent of France for about one hundred 
 thousand pounds. Our Koh-i-noor, now only one hun- 
 dred and two carats, is believed to have been part of the 
 largest real diamond recorded, the unbroken stone having 
 weighed nine hundred carats. It is supposed that the 
 great Russian diamond called the Orloff, now weighing 
 one hundred and ninety-three carats, was originally 
 another part of the same stone. 
 
 Diamonds are not always transparent, nor are they 
 only valuable for ornamentation. A vast number are 
 used for watches, and others for cutting glass. There is 
 a ready demand for them to almost any extent; and, in 
 spite of the large supply, the price is by no means 
 falling. 
 
 * The carat is the weight used all over the world to estimate the 
 diamond. It originated in India, and is equal to about three and 
 one-sixth grains troy, six carats being nineteen grains troy. 
 
GLITTERING TREASURES OP THE EARTH. 1^73 
 
 Next to the diamond in value, in beauty, and in hard- 
 ness, and in some cases rivalling or even excelling it in 
 the two former properties, are the gems obtained from 
 crystallized clay. Strange that coal and clay, the two 
 least likely substances to possess any intimate relations 
 with beauty and hardness, should, in their crystalline 
 forms, excel all others in both these respects! Not 
 more strange, however, than true. 
 
 Under the name of RUBY and SAPPHIRE the red and 
 blue varieties of crystallized clay are well known to the 
 world. They are almost all obtained from Pegu, Ava, 
 and the island of Ceylon, a singularly limited region 
 for a mineral which one might expect would be widely 
 distributed. Like the diamond, they are obtained by 
 washing gravel, and all the varieties occur in the same 
 district. These varieties include the Oriental sapphire, 
 the Oriental ruby, the opalescent ruby, the star ruby, the 
 green, yellow, and white sapphires, and the Oriental 
 amethyst. Most of them are extremely rare, and all 
 the finest specimens are believed to be still retained in 
 the East. As, however, these stones of Eastern princes 
 are rarely cut, and no doubt many of them would be 
 found affected with flaws, their real money value, if in 
 the market, would be very inferior to their estimated 
 value. 
 
 There is a useful mineral of extreme hardness the 
 corundum of commerce, from which the hardest and 
 finest emery is obtained which is an imperfect and 
 opaque crystallization, of the same origin as the ruby and 
 sapphire. The gems themselves are clear, though rarely 
 colorless. Small specimens are much less valuable rn 
 
274 THE TREASURES CONTAINED IN THE BOOK. 
 
 proportion than larger sizes, for they are far more abun- 
 dant; but a perfect ruby of five carats is worth twice as 
 much as a diamond of the same weight, and one of ten 
 carats three times as much. 
 
 The ruby was called by the Greeks anthrax, or live 
 coal, from its brilliant blood-red color and exquisite 
 beauty, which, like the diamond, is rather improved than 
 diminished when seen by artificial light. From the 
 intense blaze of blood-red, the colors of the ruby pale 
 down by admixtures of blue through rose-red to lilac. 
 Exposed to the rays of the sun, or heated, the ruby, like 
 the diamond, becomes phosphoric. In the Middle Ages 
 it was believed to be an antidote to poison, to dispel bad 
 dreams, and to warn its owner of misfortune by a dark- 
 ening of its color until the danger was past. 
 
 There is a very celebrated ruby set under the back 
 cross in the crown of England. It remains in its natural 
 shape that of a heart and has received no polish. 
 Its color is that of a Morella cherry, and it is semi- 
 transparent. It was brought from Spain by Edward 
 the Black Prince, and was afterwards worn by Henry 
 the Fifth at Agincourt. Other rubies of very large size 
 are recorded, but few of them are polished, and fewer 
 still are cut. 
 
 The sapphire is an exquisite blue variety of ruby, soft, 
 rich, velvety, and delicate in the extreme by day, but 
 losing much beauty by artificial light, even sometimes 
 changing its tint. Occasionally it sparkles with great 
 vividness in the sun, as a star with distinct rays, but such 
 stones are only semi-transparent. There is a violet 
 variety, called by jewellers the Oriental amethyst. It 
 
GLITTERING TREASURES OF THE EARTH. 275 
 
 is a gein of great rarity and beauty, and takes a very bril- 
 liant polish, owing to its extreme hardness. 
 
 Like the ruby, the sapphire was held by the ancients 
 and during the Middle Ages in high honor. It was con- 
 sidered emblematic of purity. To look at one preserved 
 the eyesight ; placed on the brow, it stopped haemorrhage. 
 The powder of sapphire was a sovereign remedy against 
 plague and poison, and if merely placed over the mouth 
 of a phial containing a venomous insect, the insect died 
 on the instant. It is a Jewish superstition that the first 
 tables of the law given by God to Moses were of this 
 stone. It is certain, at any rate, that both rubies and 
 sapphires have long been employed in the East to en- 
 grave upon, notwithstanding their great hardness. 
 
 Who has not looked with admiration at the rich, soft, 
 lively meadow-green of the EMERALD? It is a gem 
 which, when pure, comes next in value to those hard, 
 brilliant stones just described; but large specimens with- 
 out flaw are really almost unknown. It loses nothing by 
 exposure to artificial light. 
 
 The emerald is the lightest of all the clear valuable 
 gems. It is soft, and is found in regular crystals, often 
 with the rock in which it has been formed. These crys- 
 tals are long, six-sided prisms, and, though formerly found 
 in the East, are now met with only in Peru; and, indeed, 
 it is only of late years that even this resource has been 
 available. The largest stone on record was in the Great 
 Exhibition of 1851, and weighed nearly nine ounces. It 
 measured two inches in length, and two and a quarter 
 inches across. 
 
 A singular superstition has at all times attached to 
 
276 THE TREASURES CONTAINED IN THE BOOK. 
 
 emerald-mines. From the age of Pliny , when the 
 Scythians obtained these stones, to our own times, 
 there is a belief that the mines are guarded by de- 
 mons, griffins, and wicked spirits. The mine "Las Es- 
 rneraldas," in Peru, could not be visited by Mr. Steven- 
 son, " owing to the superstitious dread of the natives, 
 who assured me that it was enchanted, and guarded by 
 a dragon, who poured forth thunder and lightning on 
 those who dared to ascend the river" that led to the 
 mine. 
 
 In the East, emeralds are admired for extent of sur- 
 face rather than for beauty of any other kind, and vast 
 multitudes were sent over at the time of the Great Ex- 
 hibition in 1851, most of which were mere slices of crys- 
 tals marked with many a flaw. Many of them were set 
 as the ornaments of saddles and other horse and ele- 
 phant trappings, and others were in jade boxes and cups 
 of agate. 
 
 The emerald, like the gems already mentioned, has 
 been regarded as possessing remarkable properties, re- 
 storing sight and memory, guarding from epilepsy, put- 
 ting evil spirits to flight, and, if unable to do good, 
 shivering into atoms; for, in the words of a great author- 
 ity on these subjects, " Elle doit ou lever le mal ou ceder 
 comme s'avouant vaincue par le plus fort dans le combat 
 qu'elle rend/'* That is, it ought either to remove the 
 evil or acknowledge itself vanquished. The emerald 
 taught the knowledge of secrets, it bestowed eloquence, 
 
 * Boetius de Boot. Trait6 des Pierreries, 1. ii. ch. 53, p. 253. 
 
GLITTERING TREASURES OP THE EARTH. 277 
 
 and it increased wealth, Even more than this, we have 
 the poet's warrant that 
 
 It is a gem which hath the power to show 
 If plighted lovers keep their faith or no: 
 If faithful, it is like the leaves of spring; 
 If faithless, like those leaves when withering. 
 
 L. E. L. 
 
 Such are the recorded qualities of this beautiful gem : 
 we may worship the excellence of the diamond, and 
 wonder at the deep mystery of the ruby or the cold 
 brilliancy of the sapphire, but no one can fail to love the 
 soft beauty of the emerald. 
 
 BERYL is a mineral much more commonly found im- 
 pure and cloudy than capable of use as a gem. When 
 in the latter state, it is of a transparent bluish-green or 
 sea-green color, passing into blue by many shades. It is 
 hence called aqua-marine. It resembles in many re- 
 spects the emerald, but is less valued. It is also more 
 widely distributed. Formerly it was regarded as espe- 
 cially efficacious in liver-complaints, idleness, and stu- 
 pidity. 
 
 The TOPAZ is a beautiful gem of bright citron, clear 
 gold, or deep orange-yellow color, sometimes soft and 
 satin-like, sometimes hard and clear. What is sometimes 
 called the Oriental topaz is really a yellow sapphire; 
 but the gems properly recognized under the name are 
 mostly from Brazil, though also found in Saxony and 
 elsewhere in Europe. They were much valued by the 
 ancients, as well for medicinal purposes as for dispelling 
 enchantments and calming frenzy; but they must have 
 24 
 
278 THE TREASURES CONTAINED IN THE BOOK. 
 
 been especially useful if, as supposed, they strengthened 
 the intellect, brightened the wit, and cured the bearer of 
 cowardice. 
 
 Topaz is not a very valuable stone; but there are some 
 varieties of color, such as the red, occasionally mistaken 
 for ruby, and the blue, which are of great beauty and 
 interest. 
 
 GARNETS are comparatively common stones, and are 
 much used for ornamental purposes. They vary a good 
 deal in composition and color, and the varieties are 
 known by many names. The finest of all is the Sorian 
 or Oriental garnet, called generally carbuncle. Its color 
 is a rich blood-red, passing into violet, but acquiring an 
 orange tinge by artificial light. Fine specimens might 
 easily pass for rubies, if they were not readily distin- 
 guishable by their greatly inferior hardness. It is often 
 cut in facets, and takes a high polish ; and the resem- 
 blance to the ruby or sapphire group of gems is increased 
 by an occasional six-rayed star seen in the paler and 
 bluer specimens. 
 
 Hyacinth is a beautiful orange or scarlet garnet found 
 in Brazil; but it is rare. It is nearly allied to Zircon, 
 which has a deep honey tint. All these stones are com- 
 paratively soft, and they are less used now than formerly. 
 As a group, they were once valued as a protection against 
 the plague. They are comparatively inexpensive jewels 
 in rings and bracelets. 
 
 MOON-STONE, sun-stone, amazon-stone, and other crys- 
 talline varieties of the mineral called felspar, deserve 
 notice as gems which occasionally possess a considerable 
 value. The moon-stone is translucent and opaline, sun- 
 
GLITTERING TREASURES OP THE EARTH. 279 
 
 stone contains spangles of mica which look yellow like 
 gold in some lights, and amazon-stone is a fine green 
 crystal with a beautiful play of colors. All have a pecu- 
 liar silky appearance, and are much harder than the 
 somewhat similar varieties of quartz minerals, which we 
 next allude to. 
 
 The group of quartz gems includes many varieties of 
 color, and stones of various degrees of value and interest. 
 Pure QUARTZ, or ROCK CRYSTAL, is rather used to look 
 through than to look at, although not unknown as an orna- 
 ment. The lenses of spectacles are made of it, and it is 
 cut into various fanciful forms. Round globes of crystal 
 are the magic spheres in which some gifted seers can learn 
 what is doing at distant spots, and perceive events that 
 have long passed away, as if still in progress. They are 
 curiously bound up with the superstitions of the ancient 
 and modern Egyptians. Tinged with color, but still 
 clear, the same mineral is called by many names. A 
 rose-colored variety resembles the ruby; a purple or violet 
 kind is the amethyst. Tinged with brown and yellow, 
 it becomes the cairngorm of Scotland. Of a blood or 
 flesh-red color, passing into orange and yellow, it is 
 known as carnelian ; and a rich brown opaque quartz, 
 glittering with golden spangles within its substance, is 
 called aventurine. From its beauty and convenient hard- 
 ness, carnelian and its varieties are much used by lapida- 
 ries, and are brought, either cut or uncut, from many 
 parts of India, and from Arabia, as well as found in 
 Europe. 
 
 Jasper and blood-stone, or heliotrope, consist of quartz 
 colored in a more decided manner than the stones just 
 
280 THE TREASURES CONTAINED IN THE BOOK. 
 
 mentioned, the former being altogether opaque, and of 
 a brilliant blood-red, while the latter is partially transpa- 
 rent, or translucent, spotted only with opaque red. 
 
 Agate may be best described as a mixture of almost 
 all the different varieties of quartz above mentioned. It 
 is partly transparent, partly opaque, and of various colors; 
 often banded, but the bands broken and interrupted ; and 
 containing strange figures, representing moss, landscapes 
 with ruins, and angular marks like fortifications, stars, 
 and even human faces. Agates are found abundantly in 
 Scotland, principally near Perth and Dunbar, but also on 
 many parts of the coast of England, among the pebbles 
 on the sea-shore. They are still more common at Ober- 
 stein, in the Palatinate, not far from the town of Bingen, 
 on the Rhine; and multitudes come from Siberia, Ceylon, 
 and India. From the latter locality especially are ob- 
 tained the large plates of agate used for manufacturing 
 snuff-boxes and other purposes, and also the pieces used 
 for knife-handles. 
 
 The onyx, sardonyx, and chalcedonyx are banded 
 agates of peculiar kind, and of considerable interest in 
 the arts as having been selected for some of the master- 
 pieces of engraving executed by the ancients and in the 
 Middle Ages. Using the word sard as indicating the red 
 or flesh-color of the carnelian, a sard with one layer or band 
 of white is considered to be an onyx; but if there be 
 two or more bands of different tints, the same name is 
 still applied. The zones of color should be very distinct, 
 separate, and strongly marked, and the colors themselves 
 lively and bright. In the sardonyx there is a red zone, 
 
GLITTERING TREASURES OF THE EARTH. 281 
 
 in addition to that which forms the true onyx, and the 
 chalcedonyx is semi-transparent and milky. 
 
 In cutting the onyx, the figures are usually sculptured 
 from the white portion, leaving the colored band as a 
 background; and no little ingenuity is required to select 
 the parts of the stone best adapted for the purpose of the 
 artist. With three or four bands, a wonderful amount 
 of variety may be obtained, so that the hair, beard, and 
 drapery of figures are accurately represented. Fine an- 
 tiques thus sculptured on the onyx are of extreme value, 
 and the art of cutting was also carried on in perfection 
 during the Middle Ages. The works of this kind are 
 true cameos, and of late years they have been imitated 
 by a similar but much easier process of cutting on certain 
 sea-shells, also possessing bands of different color. 
 
 Besides cameos or raised figures cut on this class of 
 stones by removing part of the upper belt or zone, other 
 beautiful effects have been produced, such as sculpturing 
 complete figures, taking advantage of the peculiarities of 
 the specimens operated on, and still more frequently bold 
 alto-relievos, and deep cuttings beneath the surface, the 
 latter forming intaglios for seals and other purposes. It 
 is impossible to over-estimate the ingenuity and high art 
 exercised in these works ; and the demand for them was 
 at one time so great that onyxes became scarce. Few 
 now carry on the art with success, and thus we must seek 
 for the finest specimens among the antiques or mediaeval 
 specimens. One remarkable cameo was cut in the fif- 
 teenth century, representing the head of Dejanira, in 
 which the different tints of the stone were made use of 
 to represent, in their natural colors, the flesh and hair of 
 
 24* 
 
282 THE TREASURES CONTAINED IN THE BOOK. 
 
 Dejanira and the lion's skin; while a red streak in the 
 stone, which might otherwise have appeared as a flaw, 
 was so cleverly taken advantage of for the inner side of 
 the lion's skin that it gave it the appearance of having 
 been recently flayed from the animal. It is especially 
 this adaptation of the treatment of the subject to the 
 peculiarities of the stone that characterizes the "glyp- 
 tic" art as a department of sculpture. It is the depart- 
 ment that treats in relief or intaglio these banded stones 
 so capriciously moulded by Nature, taking advantage of 
 their accidents of structure. 
 
 It is curious that while almost all other stones called 
 "precious" were worn in former times as amulets, to 
 ward off danger and mischief, and were valued greatly 
 for such purposes, and while almost all the varieties of 
 agate had special uses, the onyx was considered to excite 
 spleen, melancholy, and mental disturbance in the wearer, 
 especially when used as a neck-ornament. As, however, 
 the ordinary agate was worn to calm pain and soothe the 
 mind, and the mere scent of some varieties a pecu- 
 liarity difficult to ascertain the existence of would turn 
 away tempests, even arresting the impetuosity of torrents, 
 the line of distinction must have been very nicely drawn. 
 So influential were stones of this kind supposed to be, 
 that the celebrated Milo of Crotona is said to have been 
 indebted to a certain chalcedonyx that he wore for the 
 execution of his feats of wonderful strength. Of the 
 other stones, the beautiful heliotrope, or bloodstone, was 
 thought to render the wearer invisible, while jasper would 
 stop any excess of bleeding arising from natural causes. 
 
 All the minerals lately mentioned consist of quartz or 
 
GLITTERING TREASURES OF THE EARTH. 283 
 
 silica, combined, when colored, with a small quantity of 
 metallic oxides and earthy minerals. Thus, the amethyst 
 and other violet and blue colors are produced by manga- 
 nese, and the rose tint is owing to the same metal. Al- 
 most all the reds are due to iron, and the yellow and 
 green to very minute quantities of chrome, copper, or 
 other metals. The brown tint of the cairngorm is the 
 result of a little bitumen. 
 
 It is astonishing to consider how very small a quantity 
 of foreign material will sometimes alter the character and 
 appearance of crystals. Thus, the cat's-eye is a gem of 
 greenish tint, milky and opal-like. When cut in a cer- 
 tain way, it presents a floating white band of light, and 
 certain specimens emit one or more brilliant rays, colored 
 or colorless, issuing apparently from one point, and ex- 
 tending to the extremity of the stone. Compared with 
 one of those balls of crystals sometimes cut into the same 
 form, or with the lens of a pair of pebble spectacles, it 
 is hardly possible to imagine that there is so little differ- 
 ence as really exists between the two minerals in their 
 chemical composition. In point of fact, the presence 
 within the crystal of a few delicate threads of white 
 asbestos seems to produce all the modifications, except 
 that of color; and the cause of the color itself is owing 
 to some substance the quantity of which is too small to 
 enable chemists to determine its nature. Certainly the 
 method of small doses, as advocated by homoaopathists, is 
 not without a certain analogy in Nature; and doses too 
 small to be appreciated by mortal chemistry are suffi- 
 cient, sometimes, to produce results on minerals rather 
 startling in their magnitude. 
 
284 THE TREASURES CONTAINED IN THE BOOK. 
 
 There is one fact with regard to specimens of quartz 
 or crystals, as they are often called which is very 
 curious and interesting. Small cavities not unfrequently 
 occur within them, sometimes empty, but often filled 
 with fluid. By exposure to cold, this fluid may be frozen, 
 and very often a slight increase of temperature converts 
 it into a transparent vapor; while by optical methods of 
 examination employed under the microscope, the pro- 
 perties of the fluid can occasionally be detected. Indeed, 
 the cavities have. been so large that the fluid could be 
 extracted in sufficient quantity for examination. It 
 might be expected that some new element or compound 
 would be thus obtained, some secret of Nature's labora- 
 tory, some substance from the interior of the earth, only 
 thus brought within our knowledge, locked up in one of 
 the hard crystalline minerals elaborated far beneath, out 
 of our sight. No such result is obtained, and no such mys- 
 tery laid bare; for we find almost all the cavities in ques- 
 tion to be occupied by water, mixed only with some com- 
 mon salt or acid, held in solution. Vapor of water, then, 
 must be contained in rocks during the whole period of 
 their formation in the earth, much in the same state of 
 admixture in which we know that it is present in the 
 atmosphere to form clouds. Thus these wonders of Na- 
 ture and treasures of art are the result of some process 
 only the more wonderful because it is so extremely 
 simple, being one by whose agency ordinary familiar sub- 
 stances are worked up, together with water, under cer- 
 tain conditions of heat, bringing about in this way the 
 magic of our most varied and beautiful gems. 
 
 Mixed with water in a different way, the water dis- 
 
GLITTERING TREASURES OF THE EARTH. 285 
 
 tributed in every part, and not collected in cavities, the 
 same mineral, quartz or silica, becomes that very curious 
 and fantastic stone, the opal. The proper color of this 
 gem is a peculiar pearl-gray, showing a fluctuating pale 
 red or wine-yellow tint when seen between the eye and 
 the light. With reflected light, it presents all the colors 
 of the rainbow, showing a flame-red, violet, purple, blue, 
 emerald-green, and golden yellow. The rays of light and 
 color shoot forth from a fine opal (noble opal, in technical 
 language) with the most vivid effulgence; and the more 
 flaws it contains the more does it reflect, and the greater 
 value is attached to it. In some rare cases opals have 
 been found nearly black, but glowing like a fine ruby. 
 Other opals are spangled, and sometimes not more than 
 one color is seen. In all cases, however, the foundation 
 of the stone, independent of the color, which is believed 
 to be a mere optical effect, consists of a peculiar milky 
 translucent mass, characteristic of the gem. 
 
 Opals are very rarely found of large size, the dimen- 
 sions of a hazel-nut or walnut being seldom exceeded. 
 They are never cut in facets, and are generally set sur- 
 rounded by brilliants, whose bright, dazzling reflections 
 contrast well with the calm, moon-like beauty and rich, 
 soft tints of the central stone. Fine opals are of great value, 
 being considered only next to the diamond. They are 
 softer than crystal, and require extreme care in cutting. 
 They generally consist of about ninety per cent, silica 
 and ten per cent, water, and are very irregular in texture 
 and hardness. There are many varieties, all inferior in 
 value to the noble opal, known by various names. Fire 
 
286 THE TREASURES CONTAINED IN THE BOOK. 
 
 opal, liydropliane, cachalong, may be mentioned as among 
 these. 
 
 TURQUOISE is a mineral of great beauty, taking rank 
 as a gem, though not crystalline, and always nearly 
 opaque. It is of a fine azure blue or bluish-green color, 
 slightly transparent at the edges, and hard enough to 
 admit of a good polish. It is found in the East, and (of 
 late years at least) chiefly in Arabia and Persia, whence 
 considerable numbers have been obtained. It owes its 
 color to the presence of copper, and was formerly more 
 commonly used and more valued than at present. A 
 superstition was connected with it, as with so many gems, 
 and the possession of this stone, if given to the wearer, 
 not purchased, was believed to ward of! any threatening 
 danger. Thus, we read in Donne, 
 
 " As a compassionate turkois that doth tell, 
 By looking pale, the wearer is not well." 
 
 And again, in the play of " Sejanus," by Ben Jonson, 
 
 " Observe him as his watch observes his clock, 
 And, true as turkois in the dear lord's ring, 
 Look well or ill with him." 
 
 This stone was also believed to prevent and relieve 
 headaches and appease hatred. 
 
 There are some other substances regarded as gems, 
 which though originating with the animal strictly be- 
 long to the mineral kingdom; and others, again, which 
 have the same relation to the vegetable world. Pearls 
 are among the former, and amber is an example of the 
 latter. Coral is a more decided animal product. 
 
GLITTERING TREASURES OF THE EARTH, 287 
 
 PEARLS, as all know, are obtained from the insides 
 of certain sea-shells, and they appear to be the result of 
 an effort of the animal inhabitant and constructor of the 
 shell either to repair an injury or to cover up a foreign 
 body which has been introduced. They are, however, 
 mineral secretions, and, once deposited, the constructor 
 would seem to have nothing more to do with them, as 
 they play no part in the organization of the healthy 
 animal. They are obtained both from the Eastern and 
 Western hemispheres, and from shells varying a good 
 deal in their form and structure, generally, however, in 
 those having two valves. The number of small pearls ob- 
 tained and sent into the market is exceedingly great, but 
 specimens of any considerable dimensions are as rare as 
 they are valuable. Those of good round form and pure 
 clear color are the best : the pear-shaped are the largest. 
 Pearls do not bear exposure to damp nor to animal exha- 
 lations. They should thus be kept dry, and only worn 
 on special occasions. 
 
 AMBER is a fossil resin, originally the secreted juice 
 of some extinct species of pine, and it often contains, 
 embalmed within it, remains of insects and even the 
 most delicate parts of flowers. Its exquisite yellow color 
 and beautiful transparency, together with its delicate 
 perfume and some other properties, have caused it to be 
 regarded as a gem. It is found in nodules or lumps on 
 the sea-shore, chiefly in Northern Europe, or in clay-pits 
 at various depths, with lignite and gravel. The speci- 
 mens containing insects, &c. are highly valued as curiosi- 
 ties, but not as precious stones. Amber was formerly 
 much more in use as a gem than it is now, and in the 
 
288 THE TREASURES CONTAINED IN THE BOOK. 
 
 form of beads, bracelets, and necklaces, it was a common 
 ornament of the person in England in the time of 
 Shakspeare. It is not now altogether out of fashion, and 
 its lightness and elegant simplicity are worthy of some 
 attention. Medicinal properties were at one time attri- 
 buted to it, and it is still used for perfumes and some 
 medical compounds; but there is no difficulty in manufac- 
 turing it artificially. 
 
 CORAL, if not a gem, ranks with the class of orna- 
 mental minerals we are now considering. It is not, how- 
 ever, like the pearl, an extraneous secretion, unnecessary 
 and useless to the animal that constructs it, but the 
 skeleton or stony framework of the animal itself. The 
 only kind of coral of important value is that beautiful 
 red variety fished up in the Mediterranean. This has 
 been regarded as a talisman against enchantments, witch- 
 craft, venom, the assaults of the devil, thunder, and 
 marine tempests. Ten grains of it, we are told, if given 
 to an infant in its mother's milk, provided it be a first 
 child and this its first food, will preserve it from epi- 
 leptic and other fits for the whole of its life. Another 
 great authority in matters of this kind believes that 
 coral worn by a healthy man will be of a handsomer and 
 more lively red than if worn by a woman, and that it 
 becomes pale and livid if worn by one who is ill and in 
 danger of death. We can only say with regard to this 
 that we have not ourselves tried the experiment, and that 
 perhaps, like many other experiments, it would succeed 
 only in the hands of the faithful. 
 
 There are many curious superstitions and fancies 
 concerning precious stones, besides those we have re- 
 
GLITTERING TREASURES OF THE EARTH. 289 
 
 ferred to; and one of them, which, as it is elegant and 
 fanciful in its absurdity, is perhaps worthy of mention 
 in this place, includes almost the whole group of gems 
 used for ornament. It is a Polish idea that every human 
 being is born under the influence of some destiny, that 
 the month of his nativity has a mysterious connection 
 with this, and that wl m it is desired to make a present 
 to one greatly valued i id loved, a ring should be offered 
 containing a gem expressing some such quality as the 
 destiny would indicate. Each precious stone thus has 
 reference to some particular month; and the following list 
 is copied from a memorandum drawn up by a Pole many 
 years ago : 
 
 January. Hyacinth or garnet. Constancy and fide- 
 lity in every engagement. 
 
 February. Amethyst. Preserves the wearer from 
 strong passions, and insures peace of mind. 
 
 March. Bloodstone. Courage and success in dangers 
 and hazardous enterprises. 
 
 April. Sapphire or diamond. Repentance and inno- 
 cence. 
 
 May. Emerald. Success in love. 
 
 June. Agate. Long life and health. 
 
 July. Carnelian and Ruby. Forgetfulness, or cure 
 of evils springing from friendship or love. 
 
 August. Sardonyx. Conjugal fidelity. 
 
 September. Chrysolite. Preserves from or cures folly. 
 
 October. Aqua-marine or Opal. Misfortune and hope. 
 
 November. Topaz. Fidelity and friendship. 
 25 
 
290 THE TREASURES CONTAINED IN THE BOOK. 
 
 December. Turquoise or Malachite. Brilliant success 
 and happiness in every circumstance of life. 
 
 Another curious superstition concerning gems is that 
 the twelve apostles were symbolized, each under some one. 
 The list is curious ; but one can hardly see the meaning 
 of the allusions. It is as follows: 
 
 St. Peter Jasper. 
 
 St. Andrew Sapphire. 
 
 St. James- Chalcedony. 
 
 St. John Emerald. 
 
 St. Philip Sardonyx. 
 
 St. Bartholomew Carnelian. 
 
 St. Matthew Chrysolite. 
 
 St. Thomas Beryl. 
 
 St. Thaddeus Chrysoprase. 
 
 St. James the Less Topaz. 
 
 St. Simeon Hyacinth. 
 
 St. Matthias Amethyst. 
 
 The stones in this list are sometimes called the Apostle 
 Grems. 
 
 Jet can hardly be called a gem or precious stone, but, 
 with malachite, lapis lazuli, jade, and some other stony 
 minerals, it hovers on the confines of this costly series of 
 natural treasures. Many highly ornamental and beauti- 
 ful varieties of stones, common enough in other forms, 
 might readily be quoted as coming under the same cate- 
 gory, but we must not detain the reader longer by a 
 mere enumeration. 
 
 We have now gone through the list of gems or pre- 
 
GLITTERING TREASURES OF THE EARTH. 291 
 
 cious stones, elaborated and lying buried in various parts 
 of the earth, and from time to time extracted for the use 
 of man. With few exceptions, all these numerous and 
 varied substances are objects of beauty and luxury, and 
 cannot be regarded in any sense as objects of necessity, 
 or even of great use. We could certainly do without 
 any one of them, and if we had them not we should 
 hardly feel the want. What lesson ought we to draw 
 from this lavish and elaborate ornamentation even of 
 those stones that are mixed up with the dust under our 
 feet ? Whence and why this marvellous beauty in things 
 that under ordinary circumstances are not seen by mortal 
 eye or come within mortal ken ? It is only when by 
 accident or design some one having wealth, the result of 
 spare and accumulated labor, is enabled to bestow a part 
 of it in rewarding those who discover or render available 
 these hidden treasures, that their beauty is seen and their 
 value recognized, and this notwithstanding that they 
 possess properties of importance distinguishing them 
 from other minerals. 
 
 It is no more a right thing puritanically to despise and 
 neglect these gems than it is to refuse to admire flowers, 
 to profess to despise beauty, or to shut our eyes to other 
 clear purposes of nature and nature's God everywhere 
 expressed. We live in a world of beauty; the green 
 carpet of verdure is beautiful, the flower brightening the 
 verdure is beautiful, the butterfly sipping the nectar of 
 the flower is beautiful, the bird pursuing the insect is 
 beautiful, and the blue sky and gorgeous clouds in the 
 heavens are also beautiful. All these are for our use and 
 enjoyment, and it is our duty to study them in order that 
 
292 THE TREASURES CONTAINED IN THE BOOK. 
 
 we may enjoy them. And can it be that those otoer 
 more durable treasures buried in the earth, distributed 
 only sparingly and found only when looked for properly, 
 can it be that these were meant to be neglected and de- 
 spised? Surely such an assumption is contrary to the 
 whole course of nature and the spirit and sentiment of 
 creation. 
 
Cjrapitt ilje ^i 
 
 SOURCES OF METALLIC WEALTH. 
 
 THE metals, a familiar group of natural substances, 
 having peculiar properties, are obtainable either directly 
 from the earth in what is called a native state, or by the 
 aid of chemistry from certain stony minerals, some re- 
 sembling metals in appearance, others stones in the ordi- 
 nary sense of the term, with no metallic appearance 
 whatever. Minerals thus yielding metals are called ores. 
 Several of the metals are among the most valuable of all 
 natural substances, even in the state in which they are 
 found : others are not less valuable, but in an economic 
 sense only, not being so costly, their value consisting in 
 the largeness of the quantity used, or the amount of 
 labor bestowed in their manipulation. The former 
 are sometimes called noble metals, and they have certain 
 peculiar properties by which they may be recognized. 
 The latter are more homely and plebeian, but they form 
 the main strength of the group. 
 
 Of the noble metals, some, such as gold, platinum, 
 and a few others, exist generally in the earth in the 
 metallic state, and these do not tarnish by exposure to 
 ordinary atmospheric influences. They are, for the most 
 part, comparatively rare, and some of them are only 
 known in minute quantities in one or two localities. 
 25* 293 
 
294 THE TREASURES CONTAINED IN THE BOOK. 
 
 Silver and mercury, two other noble metals, are not 
 commonly found pure and alone, being generally mixed 
 with sulphur, or existing in an earthy state as oxide. 
 They more readily alter on exposure to the air, and are 
 more common and less valuable, than the others. There 
 are thus two groups. 
 
 GOLD is the first of metals, as the diamond is the first 
 of gems j but, whereas the diamond is the rare and 
 exceptional form of coal, a substance infinitely common, 
 gold is very widely spread in the earth, the quantity 
 being small, but the metal always in its true metallic form. 
 Practically, it is not known in nature in any other form. 
 Mixed mechanically with iron, and slate, and quartz 
 rock, or mixed sometimes very intimately, but still not 
 otherwise than mechanically, with other metals, gold is 
 always gold; it is never a mere ore in the ordinary sense 
 of the term. 
 
 Australia and California now, South America and 
 Mexico in former times, India and the East at all times, 
 have yielded supplies of this most durable and most 
 valuable metal. Gold, when found, is dug out of the 
 earth much in the way that the diamond and the ruby 
 are. It lies generally mixed up with a quantity of loose 
 stones and rubbish, often at some depth below the surface. 
 It is easily recognized by its color and weight, qualities 
 which together may always decide the question as to its 
 value. 
 
 Gold is, indeed, the king of metals. It represents in 
 its own person all the important properties of metals, and 
 can be conveniently made the standard of value for all. 
 When not pure in its native state, it is only mixed with 
 
SOURCES OF METALLIC WEALTH. 295 
 
 other metals and buried in and obscured by earthy and 
 stony rubbish, from which it is extracted by washing. 
 It is often found in particles so minute as scarcely to be 
 visible to the naked eye ; but this fine dust, being pure, 
 is collected easily enough by simple processes. Else- 
 where rounded grains (pepitas, the Spaniards call them) 
 of sensible magnitude are found, few grains being so 
 large as the head of a small pin. Less frequently it is in 
 flat plates or spangles, very thin, but not so small, and 
 sometimes there are small crystals. It would take a 
 thousand of some of these spangles to make the weight 
 of a grain. Some are larger. Then come the larger, 
 rarer, and more highly valued nuggets, lumps of solid 
 gold, rich, of bright yellow color, and known at once by 
 their great weight, compared with their size. They vary 
 in size from that of a pea to masses worth thousands of 
 pounds sterling. These rare prizes in the great lottery 
 of gold-mining are fallen upon by the merest accident. 
 From the nature of the case, knowledge and experience 
 are of little value in gold-finding, as the metal is not 
 obtained from the vein where it was formed, but from 
 some old river-bed or hollow into which it has been 
 drifted after being transported by water. 
 
 Although gold has been profitably obtained in large 
 quantities from very few localities at one time, there is 
 reason to know that such an influx as has deluged the 
 civilized world within the last twenty years is not an 
 event unparalleled in history. No doubt, in former 
 times a smaller quantity entering Europe than has lately 
 been sent would have produced a larger result, for the 
 quantity and value of things represented by coin were 
 
THE TREASURES CONTAINED IN THE BOOK. 
 
 then much smaller, and communication much less rapid 
 and perfect. But that two or three times in the world's 
 history gold has poured in unexpectedly, doubling the 
 supply previously existing, and disturbing the equi- 
 librium of prices, is unquestionable. Such influx has 
 one effect, not pleasant, perhaps, but not on the whole 
 unwholesome : it reduces the value of realized property 
 as compared with the value of labor. Wages become 
 higher, and payment for labor of all kinds also becomes 
 higher, because, so many more ounces of gold being in 
 the market, one ounce will no longer purchase so much 
 food as before, and labor must have food. On the other 
 hand, the interest of accumulated money does not in- 
 crease, but rather tends to- diminish. Thus, persons 
 whose income is derived from the interest of accumulated 
 capital are directly injured by gold discoveries. Those 
 whose income arises from land suffer less, as the rent of 
 land will always have reference to the price of food. 
 
 Gold is spread very widely over the earth, and is now 
 abundant in Australia, Africa, South America, the coun- 
 tries on the Pacific slopes of the Rocky Mountains, and 
 Siberia, whence the main supply of the world is obtained 
 at present. A considerable quantity has always been 
 added from other districts, and of late years the number 
 of these has increased. The British possessions of North 
 America and New Zealand, most of the rivers of Eastern 
 Europe, especially those coming from the Carpathian 
 Mountains, and the rivers of Spain and Portugal, and, 
 indeed, almost all important rivers throughout the world, 
 have yielded indications of this wealth. Most mountain- 
 districts, even those of the British Islands, are also pro- 
 
SOURCES OF METALLIC WEALTH. 297 
 
 vided. England, Ireland, and Scotland have all in turn 
 been gold-producing countries. Wales is so now. 
 
 Gold in a native state, visible and tangible, is, then, 
 one of the most widely spread of all substances upon the 
 earth. That it is one of the most beautiful and most un- 
 alterable is, perhaps, the best reason for the high esti- 
 mation in which it is held. No exposure to weather, no 
 acids or alkaline substance, except the peculiar mixture of 
 mineral acids called aqua regia, will touch it. Although 
 by no means hard, it is wonderfully tough, and is beaten 
 into thin sheets or drawn into wire of almost microscopic 
 fineness. It is capable of being made into sheets so fine 
 that they are actually transparent and transmit a beauti- 
 ful purple light; and there seems hardly a limit to the 
 fineness of the wire made of it by coating it first with 
 silver, drawing it to extreme fineness, and then dissolving 
 off the silver by an acid which does not touch gold. A 
 mile of such wire would not weigh ten grains (less than 
 the twelfth part of the weight of a sovereign). 
 
 Although generally obtained from sands and gravels, 
 by picking out with the hand, washing carefully in 
 water, or catching hold of by mercury, which seems 
 to dissolve it and suck it up as water does salt, gold 
 is sometimes found closely combined with other metals, 
 generally, but not always, in the metallic state. Espe- 
 cially is this the case in Hungary, where it is mixed with 
 a curious and rare metal called tellurium, of no known 
 value. In Brazil and in Siberia gold is found with other 
 very rare metals. 
 
 Who has not heard of the incessant efforts of the al- 
 chemists to convert worthless substances into gold ? Vain 
 
298 THE TREASURES CONTAINED IN THE BOOK. 
 
 efforts they certainly were, and were likely to havo boon, 
 for they were made in the dark, without a foundation of 
 chemical knowledge, and often in opposition to natural 
 laws now well understood, At present the transmutation 
 of one element into another is regarded as a dream, 
 hardly justified even in a recognized Bedlamite; and no 
 doubt with reason, if the assumption is admitted that all 
 substances called elements are really so. When, however, 
 we see what Nature can do with a few gases in the case 
 of organic life, and the wonderful transmutations there 
 performed, we may be permitted to suspect that perhaps 
 all, or at least many, of the assumed elements will some 
 day yield to a mightier decomposing force than is yet 
 known, and show relations that may restore to our al- 
 chemic friends the credit due to them as hard-working 
 investigators of Nature's secrets. Then, gold may be 
 shown to have real relations as well as fanciful resem- 
 blances to other substances. 
 
 And, after all, the quantity of gold obtained is not 
 great. Look at the ugly but interesting pyramid that 
 disfigured the entrance of the Great International Exhi- 
 bition. It represented all the gold that has come from 
 Australia. A similar pyramid would represent all that 
 has come from California. A cube, measuring a few 
 yards every way, would represent more than all that has 
 ever been obtained for the use of man since the world 
 began. A block of iron of that size would hardly attract 
 attention, and in a single year more copper might be got 
 out of one mine. Why is gold so scarce in comparison 
 with other metals, and why, being so scarce, is it so very 
 universally distributed ? These are queries not replied 
 
SOURCES OF METALLIC WEALTH. 29$ 
 
 to satisfactorily by those who study such matters. But 
 one thing is certain : gold is not valuable merely because 
 it is rare. Platinum is much less in quantity, and equally 
 rare. Iridium, rhodium, osmium, palladium, these are 
 all more rare, and cannot be said to have much value, ex- 
 cept as curiosities. They have many of the properties 
 of gold, but they lack the rich color, the pliability, the 
 facility of handling, of that metal. Long as the world may 
 last, gold will no doubt continue to be the representative 
 metal, and the metal resorted to for personal ornament 
 by all who can afford to purchase it. It is the most noble 
 and royal of metals. 
 
 SILVER is even more beautiful than gold, but it is far 
 less able to resist the influence of acids, gases, and other 
 foreign substances. Unlike gold, also, it is easily tar- 
 nished; and it is especially subject to a blackening of the 
 surface by exposure to a sulphur atmosphere. Such an 
 atmosphere as arises from the presence of large numbers 
 of human beings, and the decomposition of many kinds 
 of vegetable matter, tarnishes silver. The consumption 
 of coal and the burning of coal gas set free a considerable 
 quantity of sulphur : so that in peopled districts there is 
 abundant impurity in the air to blacken the surface of 
 this beautiful metal. 
 
 Combining more readily with foreign substances, silver 
 is found not only quite as widely distributed, but occurs 
 in a much greater variety of admixtures and far larger 
 quantity than gold. It is found native as a metal, though 
 rarely of the beautiful color for which it is so much 
 admired. The form of native silver is, however, often 
 very fanciful. More frequently it is an earthy oxide or 
 
300 THE TREASURES CONTAINED IN THE BOOK. 
 
 a sulphuret; most frequently it is intimately mixed in 
 small proportion with other metals, &c. It especially 
 affects certain metals, but these are different from those 
 with which gold is associated. Antimony, bismuth, 
 cobalt, arsenic, are among the less common, lead and, 
 to some extent, copper, among the more common, metals 
 thus mixed up with silver. With lead, in its usual form 
 of galena (sulphuret), silver is almost always combined, 
 and with metallic copper it is present in a very singular 
 way, distributed .through the native metal abundantly 
 found on Lake Superior, but not forming an alloy with it. 
 As at a very moderate temperature copper and silver com- 
 bine, there is thus proof either that the metallic copper 
 has not been deposited in these veins in a gaseous or 
 liquid state, or that the silver has penetrated the solid 
 copper since its deposit to occupy blebs and cracks in 
 the metal. 
 
 A few of the ores of silver are beautiful as specimens, 
 but they are not used for personal ornament. The metal 
 itself, in its extreme delicacy and adaptability to various 
 purposes, and in the perfect polish it takes, is sufficiently 
 remarkable not to require additional interest from its 
 admixture with other substances. 
 
 The properties of silver are many. When well pol- 
 ished, it reflects more and radiates less heat than any 
 other metal. Its use for table-furniture is thus quite as 
 remarkable as its beauty. When pure, it is not so hard as 
 copper, but a very small alloy of copper hardens it with- 
 out altering its color. It is capable of being beaten into 
 leaves ten thousand of which piled together would not 
 be an inch thick; and it may be drawn into wire finer 
 
SOURCES OF METALLIC WEALTH. 301 
 
 than the most delicate human hair. A very thin coat of 
 pure silver may be deposited, by the process of electro- 
 plating, on the surface of other metals, which thus have 
 the properties of solid silver so long as the surface re- 
 mains. The salts of silver are much used in porcelain- 
 painting, in chemical manufactures, and in the laboratory. 
 
 Silver is very widely distributed. It exists, in quan- 
 tities that can be determined, in sea-water, in sea-weeds, 
 in the ashes of land-plants, and in some animal sub- 
 stances. It is present in almost all ores of lead and in 
 copper; and a large part of the silver of commerce is ob- 
 tained, by an ingenious process, from melted lead. The 
 mixed lead and silver being in a large pan in a melted 
 state, the fire is withdrawn, and the metal allowed to 
 cool. Soon crystals of pure lead form and sink to the 
 bottom. If these are removed, the liquid that remains 
 contains all the silver; and by continually removing the 
 crystals the remaining liquid is at last left extremely 
 rich in silver. When the process has been carried on 
 long enough, the silver is obtained by allowing the lead 
 to mix with oxygen gas and pass off as litharge, which 
 is either used in that state or again converted into lead. 
 A slab of silver, weighing nearly half a ton, obtained in 
 this way, was among the minerals at the Great Exhibition 
 of 1851. 
 
 MERCURY, or QUICKSILVER, is one of the noble metals. 
 At ordinary temperatures it exists at the earth's surface 
 in the form of a fluid. Near the poles, where the cold is 
 intense, it is solid, and may be hammered like lead ; but 
 this is only when the temperature is 40 below zero of 
 Fahrenheit. It dissolves several other metals in the most 
 
 26 
 
302 THE TREASURES CONTAINED IN THE BOOK. 
 
 rapid manner, and forms with them pastes, called amal- 
 gams. Gold, silver, and tin are among the metals thus 
 acted upon. 
 
 Mercury is found sometimes as a metal, and sometimes 
 mixed with sulphur, as a beautiful red stone, called cin- 
 nabar, from which the metal is obtained by distillation 
 at a low temperature. In Europe the chief mercury- 
 mines are at Almaden in Spain, in Idria (in Eastern 
 Austria), in the Palatinate (not far from Bingen on the 
 Rhine), and in Hungary. In America, California has 
 lately produced large supplies. 
 
 The fact that it remains fluid at all ordinary tempera- 
 tures renders quicksilver particularly valuable as a mea- 
 sure of heat; and its extreme weight, combined with 
 fluidity, renders it equally useful as a measure of the 
 pressure of the air. It is thus the material used both in 
 the thermometer and barometer; and its high power of 
 reflecting light renders it valuable for mirrors and for an 
 artificial horizon in astronomical instruments. 
 
 Besides all these useful properties, mercury is largely 
 used in medicine, as calomel, blue pill, &c., and much 
 more largely in obtaining the precious metals, gold and 
 silver, when they are present in small proportions mixed 
 with earthy matters. Mercury dissolves these metals 
 with great rapidity; and by afterwards applying heat, 
 the mercury passes off into vapor, and can be re-obtained 
 in bottles, while the gold or silver is left behind in a cake. 
 
 Mercury is extremely heavy, being thirteen and a half 
 times as heavy as the same quantity of water. 
 
 The next group of metals includes those sometimes 
 called base; but this is only in a technical and anti- 
 
SOURCES OF METALLIC WEALTH. 303 
 
 quated sense, and because they cannot be reduced into 
 the metallic state by mere application of heat. Of these 
 the most useful and interesting are malleable; in other 
 words, they are flattened when struck by the hammer, 
 instead of being broken like a stone. This very real and 
 important practical condition is one that divides the 
 inetals into two well- marked groups. Seven of the best- 
 known metals are malleable, and only five are brittle, 
 while there are nine rare and unfamiliar base brittle 
 metals, and only one unfamiliar metal that can be ham- 
 mered. The property of flattening under the hammer 
 is thus a good characteristic; and it is found that the 
 brittle metals are chiefly useful either to mix with and 
 harden the others, or for properties which seem to have 
 little to do with their metallic character. 
 
 Of the metals that may be hammered, we may begin 
 with COPPER, remarkable for its color, its toughness, its 
 power of mixing advantageously with other metals, its 
 high value, and its durability. In itself it is not very 
 hard, but, mixed with a little iron and tin, it becomes 
 almost as hard as steel. Of a dull red color, it assumes 
 the color of gold when mixed with a little of the clay 
 metal aluminium; it makes brass when mixed with zinc, 
 and affords several other valuable yellow compounds with 
 zinc, lead, and tin; mixed with tin only, it produces 
 bronze, a most valuable hard alloy, used for guns, for 
 public monuments, and to a large extent now for small 
 coins. At least three thousand tons' weight of metal 
 are required for the latter purpose in England only. Of 
 this the proportion of tin is four parts, and of zinc one 
 part, in a hundred : the rest is copper. 
 
304 THE TREASURES CONTAINED IN THE BOOK. 
 
 Copper has been in use from time immemorial. Ob- 
 tained by the ancients from the island of Cyprus, it was 
 called for a time ses Cyprium, or the Cyprian metal. 
 Thence the name Cuprum was derived, and from this 
 most of the modern European names copper, cuivre, 
 kupfer, cobre, &c. have been derived. 
 
 Copper is found sometimes in very large quantities, 
 nearly pure, or mixed only with silver and a little quartz. 
 In this state a block weighing 500 tons was lately dis- 
 covered in the mines on Lake Superior. It is so very 
 tough a substance, that when these large masses are dis- 
 covered they are very difficult to take out of the mine. 
 As many as forty men, working continually for twelve 
 months, were required to remove the block just alluded 
 to. But the value is very great, varying from a80 to 
 120 sterling per ton. At 100 a ton, the block in 
 question would be worth 50,000, and well pay any ex- 
 pense of getting, refining, and carrying to market. 
 
 The usual mode in which copper is found is either as 
 a hard metallic stone of a yellowish color, called copper 
 pyrites, or as a softer and very beautiful green stone, 
 called malachite. There are many other varieties, some 
 common enough in certain places, and quite different 
 from these. Among them we may mention a peculiar 
 black earth (black oxide), and a gray stone, the latter 
 metallic in its appearance, and not unlike black lead. 
 From these the copper is obtained by a long and difficult 
 series of operations, beginning with roasting, and involv- 
 ing a frequent refining. 
 
 Malachite is a wonderfully beautiful stone, used some- 
 times as a marble, or even as a gem, and at other times 
 
SOURCES OF METALLIC WEALTH. 305 
 
 as an ore from which the metal is obtained. The finest 
 malachites are obtained from Siberia, whence the raw 
 material has been quarried for those magnificent speci- 
 mens of green marble which grace the palaces of the 
 world. The largest quantities come from Australia, 
 where, however, the quality is not so fine. 
 
 LEAD is another metal of great value, and tolerably 
 abundant in most parts of the world. Most of the great 
 lead deposits consist of a combination of sulphur with the 
 metal ; but though the sulphurets of lead (galena^ are 
 very widely spread, they are not the only valuable ores. 
 Carbonates are common, especially in those numerous 
 instances where limestones enclose the lead-vein. Lead 
 is never found in a native state as a pure metal, and 
 when obtained from the ore it is generally mixed with 
 silver. It is, however, reduced without much difficulty, 
 as it melts at a low temperature, and, as already stated in 
 speaking of silver, separates readily from that metal while 
 cooling. 
 
 Pure lead is used in sheets or pipes for various pur- 
 poses; but it is dangerous, as pure water dissolves a part 
 of it and becomes very poisonous : when used for house- 
 hold purposes, great care is required. It mixes with 
 many other metals, and forms some useful and important 
 alloys. Thus, with tin it makes pewter and the solder 
 used by glaziers; with tin and antimony it becomes hard, 
 and slightly enlarges while cooling, thus forming a most 
 useful compound for such purposes as type-metal. Al- 
 loyed with arsenic, by which it is much hardened, lead 
 becomes available for shot; and other combinations are 
 known. The oxide of lead is called irwissicot and litharge, 
 26* 
 
306 THE TREASURES CONTAINED IN THE BOOK. 
 
 used in making flint glass, and for many other purposes. 
 Another combination, with oxygen, is called red lead, 
 and is useful as a pigment, though dangerous from its 
 poisonous properties. Carbonate of lead, as white lead, 
 is a valuable paint, though injurious, as are so many of 
 the combinations of lead to those exposed to their influ- 
 ence. A yellow paint is obtained from the chr ornate of 
 lead; and sugar of lead (the acetate obtained by the 
 action of vinegar or acetic acid on sheet lead) is used in 
 dyeing, and for many purposes, but is also poisonous. 
 
 Lead, like copper, has been used from the most ancient 
 times. It is easily recognized as an ore, owing to its 
 great weight as compared with other stones. 
 
 IRON. Although it seems certain that hard bronze 
 was long in common use for many purposes now supplied 
 by iron, before iron and steel had been generally intro- 
 duced, it is quite impossible to state when or how this 
 extremely abundant and useful, but most refractory, metal 
 was first discovered. It rarely exists native except in a 
 few stones that seem to have come to the earth from with- 
 out. It is found, however, in a vast variety of forms, 
 mixed in larger or smaller quantity with almost all earths, 
 and occasionally in vast quantities in different districts. 
 England is especially rich in the earthy ores; Sweden 
 contains extremely large deposits of the oxide, valuable 
 for making the best kinds of steel; but there are few, if 
 any, countries without a supply in some form or other. 
 The common clay ironstones of Great Britain have long 
 been the sources whence iron has been manufactured to 
 supply the world. No sooner had symptoms of ex- 
 haustion shown themselves in one district, than fresh 
 
SOURCES OF METALLIC WEALTH. 307 
 
 deposits, almost indefinitely large, were discovered in an- 
 other; and there is now no doubt that, while fuel lasts, 
 the ores of iron will not fail. 
 
 Iron is wonderfully tenacious : when pure, it requires 
 the full heat of a smith's forge to fuse ; but in the form 
 of pig it melts at a much lower temperature. It is very 
 malleable, especially at a high temperature, and when red- 
 hot two surfaces may be united firmly and permanently 
 by hammering. This is called welding, and is a quality 
 possessed by a very small number of metals. 
 
 Some of the ores of iron are used in the arts. Thus, 
 a peculiar red or dark-brown ore (Jisematite), when re- 
 duced to a fine powder, is valuable for burnishing and 
 polishing glass. Yellow ochre is a common pigment. 
 Iron pyrites is hardly so much an ore of iron as of sul- 
 phur : it is abundant and much used. 
 
 TIN is a metal of considerable value, but, unlike those 
 hitherto mentioned, is limited to a very few localities, 
 and is hardly ever met with except in the one form of 
 oxide. It is a beautiful white metal, more resembling 
 silver than any other, and takes a high polish. It may 
 be beaten into thin leaves, which crackle and give out a 
 peculiar odor when handled. It melts easily, and burns 
 with a bright flame. It coats iron with great facility, 
 and the plates thus covered are called tin-plate. It also 
 coats copper. The salts are valuable in dyeing and calico- 
 printing. The metal is quite as much used to modify 
 others by mixing with them as by itself. Thus, with 
 copper it makes bronze, bell-metal, &c., and with bis- 
 muth and lead several curious compounds. Tin has been 
 long known, and was certainly mined in Britain before 
 
308 THE TREASURES CONTAINED IN THE BOOK. 
 
 the invasion of the Romans. It is still obtained chiefly 
 from Cornwall, though considerable quantities are brought 
 from some of the islands of the Eastern Archipelago, 
 and it has been discovered in Australia. 
 
 ZINC, as a metal, is of recent discovery, though one 
 of its ores, calamine, was commonly employed to mix 
 with copper from the earliest period, in order to form 
 brass. The metal passes off so rapidly into the air at a 
 low temperature, in the form of a white cloud, that the 
 metallic character - was long concealed. Although mal- 
 leable, zinc is tough, brittle, and unmanageable, except 
 within narrow limits of temperature. At the boiling- 
 point of water it may easily be worked ; but at a slightly 
 greater heat it may be pounded in a mortar, and when 
 cold it can hardly be bent. It is a beautiful bluish-white 
 metal, tarnishing slightly on exposure, but not wearing 
 rapidly. It is very much used for baths, window sashes 
 and frames, chimney-pots, and many other purposes. It 
 is also used as an alloy, not only with copper, to make 
 brass, but with other metals of more or less importance. 
 
 NICKEL is often seen as a separate metal, but is largely 
 used in the manufacture of German silver, of which, how- 
 ever, it only forms four parts out of a hundred, the rest 
 being chiefly copper with a little zinc. Different propor 
 tions produce other white metals, much used in other 
 countries in place of silver. This result is singular, as 
 the red color of the copper is completely lost by this slight 
 admixture of other metals. The ores of nickel are rare : 
 some look metallic, but others are earthy. They are 
 chiefly mixtures with arsenic. Nickel is malleable. It 
 is remarkable that meteoric stones, falling on the earth 
 
SOURCES OF METALLIC WEALTH. 309 
 
 from the atmosphere, consist chiefly of iron ; combined 
 with nickel. 
 
 COBALT is never used as a metal, its value, which is 
 very considerable, being entirely derived from the use of 
 the oxides as a pigment. They produce the finest and 
 most durable blue color known, especially for staining 
 glass or coloring porcelain, in both which operations the 
 color has to be burnt in. Like nickel, the ores are usually 
 combinations with arsenic. One of them is a tin-white 
 metallic-looking mineral ; another is remarkable for its 
 beautiful color, like the bloom of a peach. 
 
 These are all the malleable metals. Bismuth, anti- 
 mony, and arsenic remain to be considered as useful brittle 
 metals, easily melted ; and manganese and chromium, also 
 useful, but fusible with great difficulty. 
 
 ARSENIC has already been mentioned, as occurring 
 with cobalt and nickel. It is also found native and with 
 many of the metals. As a metal, it is useless. As a 
 mineral, it is one of the most poisonous. Its presence is 
 readily detected by the garlic-like fumes it gives off when 
 heated. There are two ores, one transparent and of a 
 beautiful clear cochineal-red, called realgar ; the other 
 less transparent, and of a beautiful orange-yellow. It is 
 called orpimentj and is used as the basis of the pigment 
 called king's yellow. Although a violent poison, arsenic 
 is habitually consumed without injury by the people in 
 gome parts of the Tyrol. It is used as medicine. 
 
 ANTIMONY is also occasionally found native, but very 
 seldom. It is almost always mixed with sulphur, and 
 affords a brilliant and beautiful metallic ore. Though 
 not used alone, antimony, arsenic, and the other brittle 
 
310 THE TREASURES CONTAINED IN THE BOOK. 
 
 metals, are of considerable value in hardening the mal- 
 leable metals for certain special purposes. Type-metal, 
 hard pewter, and Britannia metal, are examples. The 
 lead on which music is engraved is hardened by a small 
 mixture of antimony. Gold cannot be hammered if 
 alloyed with a little of this curious metal. 
 
 BISMUTH is another brittle metal, with curious pro- 
 perties. It is found native, generally with arsenic ; but 
 its peculiarity is to render any metal mixed with it 
 much more fusible. What is called plumber's solder is a 
 mixture of this kind. Eight parts of bismuth, five lead, 
 and three tin, constitute a metal which will melt at a heat 
 below that of boiling water. A little mercury added 
 makes it still more fusible. Tricks are sometimes played 
 by making spoons of this metal and offering them for 
 use. The salts of bismuth are used in dyeing and as a 
 cosmetic. 
 
 MANGANESE is a metal never used, and very rarely 
 seen. Its ores are black. They are valuable for various 
 purposes, being very widely diffused and employed in 
 bleaching, dyeing, calico-printing, and in glazing and 
 coloring pottery. The umber of commerce is obtained 
 from the ore called wad. Oxygen gas is given off readily 
 by heating the ores of manganese. One ore of manganese 
 is capable of taking a high polish, and is used for inlaid 
 work as a spar. Many of the manganese ores, and stones 
 where traces of the metal occur, are remarkable for their 
 pink color. 
 
 CHROMIUM is another of the metals, brittle, not easily 
 melted, altogether without any known use as a metal, but 
 
SOURCES OP METALLIC WEALTH. 311 
 
 valuable in the arts from the color derived from it. 
 The only ore is a combination of the oxide of the metal 
 with iron and earthy substances. It is found in England 
 in serpentine and other green magnesian rocks; but there 
 are many known localities in various parts of the world. 
 It is very extensively used as a pigment for dyeing, and in 
 all those cases in which the color has to be burnt into the 
 material. 
 
 Besides the metals and ores we have described, there 
 are many others less common. These are interesting 
 rather to the chemist who analyzes than to the geologist 
 who observes them. They are some of them curious, and 
 have remarkable properties, but rather as earths than 
 metals. 
 
 It is a curious fact, determined of late years by a series 
 of observations on the nature of light and color, that 
 many of the metals forming part of our earth are present 
 also in the sun, and even in some of the fixed stars whose 
 light has been examined. As it has been known almost 
 from time immemorial that foreign substances occasion- 
 ally fall to the earth from or through the air, and these 
 are generally composed of a rare mixture of familiar 
 metals, there is some reason to suppose that various small 
 bodies, composed of similar elements, are floating about 
 in the universe, not far from us, and that these are from 
 time to time brought within our influence. Since no 
 new element has been introduced in the fallen stones, one 
 is thus led to speculate on the possibility of a common 
 origin of our own earth and the other bodies of our solar 
 system, and that some fragments of similar matter, broken 
 
312 THE TREASURES CONTAINED IN THE BOOK. 
 
 away from an old planet, or strayed from a comet, or per- 
 haps in course of collection by a comet, may yield the 
 aerolites or meteorites that have so often caused wonder 
 and alarm. The indications of this state of things are 
 more numerous and complete than is generally sup- 
 posed. 
 
THE CIRCULATION OF WATER. 
 
 OF the many conditions of Nature that require to com- 
 bine, in order that our earth may be the abode of living 
 beings having the wants and habits of those now dwell- 
 ing on it, there is none more remarkable than that which 
 has secured for us a constant circulation of water, in the 
 air, on the earth, and within the earth. The mere fact 
 that with us there are three conditions of matter solid, 
 fluid, and gaseous is itself, as far as we can judge, a state 
 of things by no means always met with in planets. The 
 moon does not seem to possess a similar arrangement : 
 Mars probably does, but Jupiter may be regarded as 
 doubtful. We can hardly guess at some of the other 
 planets. Taking the earth as we find it, however, it is 
 very interesting to see how the three states of matter seem 
 always to have characterized every part of its history. 
 
 Water in abundance rests on the surface ; the air con- 
 tains water in large quantity; and almost all the rocks 
 contain a certain quantity of water, either in such a state 
 that it courses freely from one part to another, or closely 
 shut in and buried in the very substance of the most 
 solid minerals. 
 
 Water is, indeed, present in two distinct ways in rocks. ' 
 Except lava and such-like material, once certainly fluid 
 27 313 
 
814 THE TREASURES CONTAINED IN THE BOOK. 
 
 from heat, every kind of stone, including granite and 
 marble, contains a certain percentage of water as one of 
 its component parts. The proportion is not large; but, 
 from the universality of the fact, the quantity of water 
 thus locked up is very considerable. But in addition to 
 this, and quite independent of it, there is a far larger 
 quantity of water occupying innumerable cracks and cre- 
 vices in rocks, running between beds, oozing through 
 narrow channels in all sorts of unexpected places, occu- 
 pying caverns and veins, existing in pools (often under 
 great pressure) at various depths, issuing in natural 
 springs at hill-sides in some countries, and even on moun- 
 tain-tops, or reached by artificial borings in all parts of 
 the world. We are so accustomed to find fresh pure 
 water wherever we require it we are so familiar with 
 the custom of digging a hole into the substance of the 
 earth in order to reach this fluid that the nature of the 
 continuous supply, and the circulation that takes place 
 in order to insure it, are hardly thought of. These are, 
 however, subjects as interesting as they are important. 
 
 The history of the Great Stone Book is given in the 
 preceding chapters. It points out that the earth is made 
 up of numerous beds or strata of rock of different mate- 
 rial, some absorbing water, some letting it pass freely, 
 some stopping it altogether.- The additional facts de- 
 termined concerning the fractures of these rocks, the 
 way the rocks have been tilted, the way in which deep 
 cracks have been sometimes left open and sometimes filled 
 with hard material, the mutual intercommunication that 
 exist/ far out of sight, and the 9pen passage thus afforded 
 to water, are also illustrated by the history there given. 
 
THE CIRCULATION OF WATER. 315 
 
 There is something exceedingly grand and deeply in- 
 teresting in following the course of a few drops of water 
 in its circulation though the great terrestrial system. 
 Covering two-thirds of the surface is the great world 
 of water, and above sea and land floats a veil of gases. 
 We do not see all the water. Part of it, as we have 
 described, is fast locked up in the solid rock; part 
 of it is always held in an invisible state in the air ; and 
 part, again, is sometimes visible, sometimes invisible, 
 ranging over earth and through the air, and ready at the 
 slightest signal to move and distribute itself. 
 
 Water is always present in the air, sucked up and held 
 by it something in the way that sugar or salt is sucked 
 up and held by pure water. The air itself is a mixture 
 of gases, and the vapor in it is like a third gas. Just ag 
 hot water dissolves more sugar or salt than cold water, so 
 hot air holds more water than cold air. Air, heated by 
 the vertical rays of a tropical sun, and passing over the 
 sea, becomes loaded with vapor; and as it afterwards ap- 
 proaches land and comes in contact with cooler air, espe- 
 cially on the sides of mountains, it can no longer hold so 
 large a quantity of water as before. Clouds are formed, 
 and rain falls. The air is cleared and passes on, cooled 
 and deprived of part of its load, to some place where it 
 is again heated, and where once more it absorbs water. 
 
 The solid materials of the earth we have already con- 
 sidered. Almost all were originally formed in and with 
 water; they have been rendered hard and compact under 
 water; they have existed for unnumbered ages always 
 under water; and when deprived of water they have 
 shrunk and cracked. 
 
316 THE TREASURES CONTAINED IN THE BOOK. 
 
 All stones contain water. Even the driest and most 
 solid-looking marble used by the sculptor contains at 
 least one part in two hundred of water : in other words, 
 in a block of two hundred weight there is at least a pint 
 of water. Other hard dry limestones contain as much 
 as four parts in a hundred, or half a gallon of water in a 
 hundred weight of stone. 
 
 But stones are not only made with and always contain 
 water, but they are very porous and spongy, and suck in 
 great quantities when exposed to rain or soaked in a 
 stream. Thus, Bath stone, of the kind generally met 
 with in buildings, and some other limestones commonly 
 used, will suck in as much as nine gallons of water on a 
 surface a yard square and only a foot thick. When 
 thicker, it will continue to absorb, though not in the same 
 proportion. A surface of chalk will absorb twice as 
 much, and sands are much more porous even than such 
 stones. 
 
 Of all the rocks that make up the earth, there are few 
 of those met with at the surface in our country that will 
 not suck up water with extreme rapidity and in very 
 large quantity ; and when we come to an actual calcula- 
 tion, the absorbing power of the surface, when dry, is 
 found to be so extremely great as to suck in almost any 
 amount of rain that can fall. It rarely happens, indeed, 
 except in hot summer weather, that the earth is so dry 
 as to absorb at any thing like the rate we have mentioned j 
 but on the other hand, in addition to the means we have 
 considered, there are cracks and crevices innumerable, 
 the consequence of exposure to the weather previously; 
 and thus the water is not only absorbed slowly at the 
 
THE CIRCULATION OF WATER. 317 
 
 surface, but pours down these open cracks, arid gives the 
 rocks in the interior an opportunity of becoming saturated. 
 
 Water is, then, present in the earth's interior in ex- 
 tremely large quantity: it is continually being received, 
 because it is continually being removed. Under every 
 space a mile square there is water enough present in 
 a thickness of a thousand yards to fill a pond of the 
 same area whose depth of water might be many yards or 
 even scores of yards. 
 
 Let us now bring together the general results of this 
 inquiry, and endeavor to illustrate in a few words the use 
 and influence of water in the interior of the earth. 
 
 Although not a simple substance, water is a compound 
 of which the composing elements possess affinities so 
 powerful, that the agency of electricity appears to be 
 involved both in its formation and decomposition. The 
 conversion or production of water involves heat, elec- 
 tricity, and chemical action, and this conversion is always 
 going on, for water is everywhere present : no known or 
 conceivable conditions of matter, consistent with the pre- 
 sence of more than very small quantities, appear to be 
 free from it; hardly any combinations of simple sub- 
 stances are altogether without it, and no large quantities 
 of simple substances deprived of it exist on or near the 
 earth's surface. 
 
 Water absorbs every thing and is absorbed by every 
 thing. Itself a liquid, it enters into the composition of 
 almost all solids, almost as an essential to solidity. As a 
 solid, it has its own special value and properties. It is 
 equally important in the state of vapor, for steam repre- 
 sents power not only available for man's machinery, but 
 27* 
 
318 THE TREASURES CONTAINED IN THE BOOK. 
 
 largely used in the workshop of Nature. In every con- 
 dition and at every change it is connected with heat and 
 electricity. Besides being present in almost all mineral 
 matter, it enters also into the composition of every solid 
 and every fluid of which each part of every living thing 
 is formed. 
 
 Let us trace its course from its great receptacle the 
 ocean, where it occupies and conceals depressions which 
 are little more than wrinkled or furrowed markings on 
 the earth, and which, if they could be seen from our 
 satellite the moon, must appear very small, compared with 
 the variations of level on that body. 
 
 Kept in incessant motion in all parts of the ocean by 
 tidal influences and winds, water rising as vapor from its 
 surface is received between the particles of mixed gases 
 that form our atmosphere, and there becomes subject to 
 influences of temperature and electricity; and these are 
 constantly changing by the revolution of the earth on its 
 axis, of the moon round the earth, of the earth and moon 
 round the sun, and of our whole system in space. 
 
 Lifted as vapor, it is drifted along, either in an invi- 
 sible or visible form, until it reaches land. Once there, 
 it is set free, and large quantities fall to the earth. Part 
 of what falls is re-evaporated; part serves to quench the 
 thirst of every leaf and root, as well as every mouth and 
 skin, exposed to its influence; part again runs on the 
 surface, the mountain-torrent, the brook, and the river 
 carrying back this proportion to the parent ocean. Part 
 of it whitens the lofty mountain-top, or collects in icy 
 masses in the sheltered valleys. 
 
 But a large part enters the earth. The earth and the 
 
THE CIRCULATION OP WATER. 319 
 
 sands are thirsty, as well as the leaf and the skin : they 
 not only drink in an abundant supply, but they convey 
 downwards some portion; and this reaches the interior 
 through the crevices of hard rocks, or the porous sub- 
 stance of those that are softer. 
 
 This supply is so ample that abundant springs gush out 
 from the hill-sides, or are ever ready to rise through open- 
 ings prepared for them by Nature or man. 
 
 The ultimate residuum, after all this lavish supply has 
 been granted, is still an important quantity. 
 
 And now is forced upon us a view of Nature, and of 
 the operations of Nature in the interior of the earth, 
 which is almost oppressive, from the extreme difficulty 
 the human mind has in grasping a conception so opposed, 
 it may seem, to the evidence of the senses. 
 
 We speak of the grave as silent ; we think of the 
 ground and the rock as permanent, and almost as if they 
 were eternal. We cannot feel that all beneath our feet 
 is changing, and that there is a kind of life even in dead 
 matter. We cannot see it, but a circulation really goes 
 on in all material substances, and it is consistent with 
 apparent and external repose; for if we examine and 
 carefully describe an object or a state of matter at one 
 time, and afterwards, after a sufficient interval, repeat 
 our investigation, we may find perhaps the same form but 
 a different substance : there may be the same appearance, 
 but there is a new and changed texture. 
 
 Nature, indeed, knows no repose. The minute atoms 
 of which solids are formed, however compactly placed 
 they may seem, are removed from each other by a dis- 
 tance which is large in proportion to their size, large 
 
320 THE TREASURES CONTAINED IN THE BOOK. 
 
 enough, at any rate, to admit of any amount of motion 
 among themselves, large enough to let atoms of other 
 matter circulate among and replace them, large enough 
 to allow the combined atoms of hydrogen and oxygen, 
 as water, to penetrate them. 
 
 The mud deposited to-day at the mouths of the Rhine, 
 the Granges, or the Mississippi is a mechanical mixture 
 of lime and clay and water with grains of sand, frag- 
 ments of wood and bone, marine and fresh-water shells, 
 and particles of iron oxide. With them is the infinity 
 of miscellaneae that are brought together by fresh water 
 running over a surface of land which is covered with 
 vegetation and with animal life, and ultimately the river 
 terminates its course and deposits its load where it meets 
 the tidal wave of salt water. 
 
 This mud deposited to-day will be buried to-morrow, 
 and in the course of centuries will be covered up thickly, 
 and remain permanently buried for a long time. 
 
 What then will happen? Will all remain quiet? 
 Having entered Nature's great laboratory, will these 
 materials be left there inert and idle ? Such an idea is 
 little in accordance with what we know of the course 
 of Nature, either now or at any period of the earth's 
 history. 
 
 First, decomposition will commence, or will go on if it 
 had already commenced, in the organic matter. Gases 
 will be evolved, these will affect the other compounds 
 otherwise permanent; elective affinities will be called 
 into play, and a general rearrangement will take place of 
 all the particles, until they attain a first state of tempo- 
 rary equilibrium. During all this time they are satu- 
 
THE CIRCULATION OF WATER. 321 
 
 rated with water, a heavy column of water presses upon 
 them, and their temperature is more or less equable in 
 proportion to the depth of the deposit. 
 
 By degrees the water gets to a certain extent squeezed 
 out of them, and they become solid instead of pulpy. 
 The attraction of cohesion acts, and at last the wet pulpy 
 mud either becomes changed into tough clay, or a sort 
 of half-formed limestone results, or perhaps the mass re- 
 mains loose sand. 
 
 Then come into play those movements of the earth's 
 surface of which there are examples in most countries. 
 The ground sinks, the deposit continues; and at length 
 the mud of yesterday, kept at a steady even tempera- 
 ture of some 200 or 300 under great pressure of 
 earth and water, is exposed to those magnetic cur- 
 rents which circulate through the earth. Then begins 
 a fresh series of changes, crystallization starting at 
 some atom of foreign matter. Clayey mud passes into 
 tough clay, lime-mud passes into beds of limestone, 
 impurities and foreign substances accumulate together 
 in bands, the shells become crystalline and are cemented 
 together; undecomposed wood tends to become coal, silica 
 takes the place of some of the organic matter; the 
 sulphur and phosphorus set free from animal matter 
 enter into new combinations; the mass, in drying, con- 
 tracts irregularly, and is full of cracks and fissures; and 
 among these water circulates, forced through at a tempe- 
 rature corresponding to the depth, carrying with it from 
 place to place various minerals, removing them from one 
 point, leaving them behind at others, according to the 
 nature of the chemical operations going on. 
 
322 THE TREASURES CONTAINED IN THE BOOK. 
 
 After a time the beds sink lower, the clays become 
 subject to greater pressure, the limestones become com- 
 pact and pass into marble, and the metals, combined with 
 oxygen or sulphur, group themselves together in cavities 
 with other minerals, earthy and crystalline. 
 
 One step more : elevation begins. The clays are now 
 subjected to pressure from below as well as from above; 
 and under this double squeeze they become twisted and 
 bent like pieces of cloth, and they also assume a new 
 lamination. They become slates. Some of the sand- 
 stones have by this time been converted into quartzite, 
 and the limestone has completed its crystallization. 
 When elevation comes, these hard beds, being brittle, are 
 broken, leaving large open spaces and great cavities be- 
 neath the surface. Here also water collects. 
 
 Yet again. Far down, at a depth of tens of thousands 
 of yards, and therefore under great pressure, water, in 
 company with the minerals which form granite, accumu- 
 lates in a mixed mass; and a slow but incessant crystal- 
 lization goes on, in which the water is entangled with the 
 other minerals and helps to form a part of the substance 
 of each crystal. We may even imitate the effect by 
 bringing the causes to bear. 
 
 But in all this there is no melting, such as we have 
 in volcanic rocks. In these latter water is not present 
 in the same way. 
 
 They were formed much nearer the surface; they be- 
 long to a different class of phenomena. Their origin is 
 detected by the absence of water in them. 
 
 Wherever change has taken place at great depth, - 
 
THE CIRCULATION OF WATER. 323 
 
 wherever is seen a rich variety of minerals and a valua- 
 ble supply of metals, there water has acted. 
 
 Water carried down in the rocks that descend is worked 
 up into new forms, and is only returned to the surface 
 when it has done its work and when other supplies from 
 above have replaced it. 
 
 And in time the rocks thus elaborated rise again. 
 Some, sunk only to a small depth, will have been little 
 altered, and will form gravel, surface-clay, loose sand, or 
 soft limestone; some, from greater depth and more 
 altered, will show the effect of chemical action by un- 
 mistakable chemical and atomic change, while the wealth 
 of their fossil organic remains sufficiently speaks of their 
 mechanical origin; others again, much deeper, will have 
 been so completely altered as to have lost all trace of 
 this life-origin. It does not the less follow that they 
 have once contained fossils as distinct and as numerous 
 as those of any recent deposit. 
 
 As each rock comes again within the influence of 
 surface-disturbance, it will be worn away by the river, or 
 beaten into fragments by the tidal wave; water will once 
 more destroy what water originally formed, what water 
 afterwards modified, and what will once more be con- 
 verted into a deposit at the bottom of the same ever- 
 present but ever-active element. 
 
 In all the great circle of changes concerning which 
 Geology informs us, water is, then, the chief agent. 
 Heat and chemical action of themselves could do little, 
 and certainly could not produce what is needed for our 
 world. They act with and by water, and thus produce 
 their results. 
 
324 THE TREASURES CONTAINED IN THE BOOK. 
 
 Abstract this important form of matter, and we may 
 imagine what the result would be. The great ocean 
 would be but a salt desert without an oasis, the land a 
 dry parched rock; there would be no life, animal or 
 vegetable, not even the smallest animalcule, or the red 
 lichen on the snow. The sky would be without cloud, 
 and the thermic and magnetic currents would cease to 
 vivify the dry bones that would then form but a skeleton 
 of the earth. 
 
 Water is the life of the earth, as blood is the life of 
 man. This is a wonderful and instructive analogy, and 
 one which may lead to many useful suggestions in the 
 contemplation of Nature. 
 
be Sljutting-ttp 0f % tot Stone 00ft, 
 
 'And tliis, tlie naked countenance of earth, 
 On which I gaz<-, even these primeval mountains, 
 Teach the adverting mind. The glaciers creep 
 Like snakes that watch their prey, from their far fountains 
 Slowly rolling on." . . . 
 
 " Mont Elanc yet gleams on high. The power is there, 
 The still and solemn power of many sights 
 And many sounds, and much of life and death." 
 
 ..." Winds contend 
 
 Silently there, and heap the snow with breath 
 Rapid and strong, hut silently!" . . . 
 
 " The secret strength of things 
 Which governs thought, and to the infinite dome 
 Of heaven is as a law, inhabits thee! 
 And what wert tliou, and earth, and stars, and sea, 
 If to the human mind's imaginings 
 Silence and solitude were vacancy?" 
 
 SHELLEY'S " MONT BLANC," Stanzas iv. v. 
 
 28 
 
r % < 
 
 CONCLUSION. 
 
 THE reader has been introduced to a few of the many 
 remarkable additions to human knowledge that have 
 been made by the study of that Great Stone Book, the 
 World. The history of the world, from a very early 
 date, if not from the beginning, is a history recorded at 
 every step, but of which the records are buried and con- 
 cealed as fast as they are made. It is as if each hour of 
 a human being's existence, and each action performed, 
 were instantaneously photographed, and the photographs 
 immediately thrown into a heap as they were prepared. 
 If from time to time, after the original heaping, we sup- 
 pose this curious and vast collection disturbed, if the 
 floor on which they were piled should have lost part of 
 its support, or should have partially fallen in, and should 
 be propped up and broken in the operation, if some 
 members of the series should, from time to time, have 
 been used up for other purposes, and in so far destroyed, 
 if, when all is over, the surface should be concealed and 
 its appearance changed by dust and mould, then should 
 we have a case not very dissimilar to that of our earth's 
 surface and its history, and the difficulties met with by 
 geologists in making out the history. Just as no mode- 
 
 327 
 
328 THE SHUTTING-UP 
 
 rate amount of disturbance would be likely to destroy or 
 obliterate much of the detail, or even modify the main 
 outlines of the order, while the relative position or the 
 style of the picture at any period would be a guide that 
 could be trusted to distinguish the earlier from the later 
 representations, so in the history of Nature we are quite 
 satisfied that the evidence we possess is sound and satis- 
 factory, though the details may long remain doubtful and 
 admit of discussion. Making the best use of available 
 material, it has been attempted to reproduce something 
 of reality in these .sketches, to show both how to learn 
 and what to learn in Geology, and to give some notion as 
 to how far the statements which are made have been de- 
 rived from observation. 
 
 Like all knowledge that is worth any thing, that which 
 has brought Geology to its place among the sciences is 
 cumulative, or has been derived from the accumulation 
 of isolated facts and points of evidence worked into a 
 connected history. The discoveries of to-day form the 
 basis of future discoveries, and every thing proved suggests 
 something new to prove. There is no finality in such a 
 science. The more we know and see, the wider is our 
 field of vision extended towards those distant and as yet 
 unapproached facts and those further deductions which, 
 when learnt and understood, will only open a yet wider 
 view. If we could ever thoroughly know the history of 
 our own planet, we should perhaps make use of that 
 knowledge to speculate on its relations to other planets, 
 while at present we help our geological speculations by 
 evidence deduced from observations on them. Could we 
 determine the whole succession of extinct species, we 
 
OP THE GREAT STONE BOOK. 329 
 
 might understand the mysterious laws which govern the 
 development of the race as well as the individual ; but 
 even that knowledge, great as it is, would but suggest 
 views concerning the nature of life itself. But, though 
 we never can really and fully know all or any of these 
 subjects thoroughly, we are ever approaching more and 
 more nearly towards a knowledge of them. As, from 
 time to time, we make some fresh important discovery 
 concerning them, every such discovery helps us to under- 
 stand a whole host of phenomena that before seemed 
 obscure, contradictory, and strange; and thus every step 
 secured lays the foundation for another step, every 
 light thrown upon part of a dark group helps to throw 
 light on the remaining members of the group. 
 
 The summing up of the attempts that have been 
 made, in these pages, to enable the general reader to 
 understand and take an interest in the details of the 
 earth's history, may now be presented in a few words; 
 and in stating this result I will endeavor to point out 
 not only what is already known concerning the earth, 
 but what may probably be known, whether soon or at a 
 more advanced period in the history of science, and also 
 what part we cannot hope ever to make out. 
 
 And, first, it appears that to observe, compare, and 
 record all that goes on around us, of every kind, is the 
 only path to geological knowledge. There is in Nature 
 so much that is constant, producing so much that is 
 variable, such infinite difference of effect brought about 
 by such constantly recurring causes, that, so far as the 
 present can teach, we find all reduced to a narrow limit 
 of ultimate and proximate causation. We find heat 
 
 28* 
 
330 THE SHUTTING-UP 
 
 and cold, wet and dry, storm and sunshine, always and 
 everywhere working together. There are certain che- 
 mical changes produced by these, and others that are 
 mechanical; but, on the whole, the subtle agencies at 
 work above and around us, in the air and ocean, are so 
 efficacious, that no rest is given to any material sub- 
 stance, and a constant circulation is kept up, involving 
 incessant change of the surface. To measure these 
 changes, as far as possible, to find out their ramifications 
 and their connecting links, is a study that is never- 
 ending, and always .productive of fresh discovery. It is 
 the most useful, the most suggestive, the most instruct- 
 ive, of all studies of Nature. It is open to every one; 
 it may be carried on by the rich and the poor, the 
 idle and the busy, the well-instructed and the little- 
 instructed among us. It requires only honesty, intelli- 
 gence, and earnestness. It can never fail; for material 
 is always at hand. 
 
 The study of Nature, with a view to find out the 
 mode and extent of action of present causes, is the first 
 and greatest of all preparations for pursuing Geology. 
 It is the only proper preparation; and the more com- 
 prehensive and complete it is, the better is the student 
 adapted for carrying out future investigations. No 
 department is too general, none too special, for this 
 purpose. The discovery of the law that regulates the 
 distribution of an insect, a zoophyte, or even an animal- 
 cule, may lead to discoveries of the greatest and widest 
 importance. If we knew the laws that governed the 
 introduction of the lower forms of animal and vege- 
 table life, if we even knew exactly what is the precise 
 
OF THE GREAT STONE BOOK. 331 
 
 line of demarcation between animal and vegetable life, or 
 could clearly see why certain modifications of form of 
 some of these have been induced by changes of circum- 
 stance in their development, the result could not fail to 
 have the most direct and important bearing on the whole 
 history of extinct races, and their distribution in the 
 older as well as newer rocks. If we could determine a 
 matter clearly within observation, but as yet unattained 
 the exact amount and rate of changes of level in the 
 land, on certain coast-lines that we know to be subject to 
 upheaval, and could connect that knowledge with altera- 
 tions on exposed coasts in the vicinity, or measure accu- 
 rately the change produced by the action of the tidal 
 wave in a given time, there would be a basis for gene- 
 ralizations far more accurate than can be at present at- 
 tempted. If, indeed, a very small part only of all the 
 numerous opportunities presented in Nature by the pro- 
 gress of events had been carefully and minutely observed 
 and recorded for only a single century, the state of 
 Natural Science at the present day would be far more satis- 
 factory than it is, and Geology would be far more of an 
 accurate science than it can now claim to be. But patient 
 honest observers are rare, and the work they do is quiet 
 and unobtrusive : their results, also, are rarely immediate. 
 Thus it is that, for one useful worker, there are many 
 who prefer vague speculations, and many more who only 
 amuse themselves with technicalities, and waste their 
 energies on the discovery and naming of new species or 
 new subdivisions of a recognized system of arrangement. 
 The Great Stone Book lies ever before us: it is not 
 closed by any complicated mystery, of which we cannot 
 
332 THE SHUTTING-UP 
 
 find the key; it is not written in a character we cannot 
 decipher : it is illustrated by forms of animated nature, 
 sufficiently like those now living to suggest comparison, 
 but sufficiently different to give individuality to each 
 separate group. The plan of Nature, as there shown, is 
 not different from that plan the operation of which we 
 can trace from year to year, and from century to century, 
 in the experience of generations of men. The methods 
 now adopted to bring about certain results seem always 
 to have been adopted for similar purposes. The Great 
 Overruling Power, to whom we all look as the Final 
 Cause, has ordained from the beginning certain laws, 
 some affecting all material combinations, mineral as well 
 as organic; others, developed perhaps from them, and 
 involving certain forms of life; others, again, further de- 
 veloped, and only commencing to operate when more 
 complex forms have been elaborated from those that are 
 more simple. It is the privilege of the naturalist to lift 
 the veil that conceals the working of these methods, so 
 far as it is possible to do so. Should, however, any frag- 
 ment of a system be recognized, so prone are men to gene- 
 ralize that we are apt to assume that a law is disco- 
 vered; and at once this law is supposed to be universal, 
 and to extend, or to have extended, through all time 
 and space. It may be that the system, thus doubtfully 
 perceived and imperfectly comprehended, is only a part 
 of some larger system; and, under any circumstances, we 
 certainly have no authority to assume that Nature, or the 
 God of Nature, is in any sense bound by it, or unable to 
 supersede or modify it. 
 
 Among systems and methods or laws of this kind we 
 
OF THE GREAT STONE BOOK. 333 
 
 may even name the law of gravitation, one of the 
 simplest and grandest ever promulgated, and one that is 
 believed to apply to all matter throughout the universe. 
 Of such methods also is the supposed law, according to 
 which, in organic nature, certain peculiarities of struc- 
 ture are handed down from generation to generation in a 
 plant or animal, producing what is called specific distinc- 
 tion. Certainly, it is strange that two sets of animals or 
 plants, sufficiently like in important respects, do not 
 intermingle, but always seem to continue distinct species, 
 while two others, apparently very unlike, belong to each 
 other and are mere varieties. That it is so we know from 
 experience. We may some day discover the real method 
 of Nature in this matter, and learn how it is that, as 
 time rolls on, one species has been succeeded by another, 
 some species, like some individuals, being hardy and 
 long-lived, while others are weak and short-lived, some 
 species growing out of others, apparently if not really, 
 and other species suddenly dying or suddenly appearing, 
 as place for them ceased to exist or was created. 
 
 That these dark and obscure matters are to be cleared 
 up and rendered intelligible by the study of the records 
 in the Great Stone Book, and that, on the other hand, 
 the curious and difficult problems there presented will 
 be ultimately solved by minute investigations concerning 
 Nature as she now pursues her course, is at least highly 
 probable. It is thus that Geology, and what is usually 
 called "Natural History," are connected together and 
 assist one another j and thus also the various departments 
 of Physical Science are made to bear one upon another, 
 
334 THE SHUTTING-UP 
 
 and all are found to assist in clearing up the ancient his- 
 tory of our earth. 
 
 In conclusion, if there is one lesson which, more fully 
 than any other, is taught by the Great Stone Book of the 
 World, and which chiefly needs to be impressed on the 
 mind and memory of the geological student, it is this : 
 Study to become familiar with familiar things ; observe 
 the methods now adopted in Nature to bring about cer- 
 tain results; measure and estimate their value and the 
 extent of their action. Learn how at present all things, 
 organic and inorganic, are mutually dependent, so that 
 if any one is changed all the rest are changed in accord- 
 ance, and weigh well the full meaning of this great fact. 
 In a word, endeavor to comprehend what is meant by the 
 uniform method and the infinite variety of Nature. Here 
 lies the great secret of Nature and the great charm of 
 natural-history labors. None can ever tire of studying 
 Nature; for there is always an abundant store of yet 
 undiscovered facts in the progress of the present creation 
 as well as in the history of the past. On the other hand, 
 none need fear that he may fail at coming to a safe and 
 satisfactory result; for all is the work of one Almighty 
 Power, and has been elaborated from the beginning as 
 part of one vast, comprehensive, and infinitely wise 
 scheme, in which apparent interruptions and interpola- 
 tions have been foreseen, and are but parts of the full 
 and complete development of an original plan. Surely 
 it is a higher and more noble conception of the Supreme 
 Being, and one more likely to lead to the discovery of 
 truth, to believe in the existence of a plan as perfect as 
 its Designer, than to presume that this earth has been 
 
OF THE GREAT STONE BOOK. 335 
 
 the result of a series of experiments and failures, or has 
 been the scene of great disturbances and convulsions in 
 Inorganic Nature, and of successive creations of what we 
 ignorantly call higher organisms in the world of organic 
 life ! We may never in this life succeed in discovering 
 the whole plan, for it is not likely that finite powers can 
 grasp the Infinite Design. But each endeavor that is 
 made, humbly and honestly, will be productive of good: 
 and the student will rise from the study of any part, 
 either of the works or the method, with wider and clearer 
 views, and be better fitted to perform his other duties and 
 be useful to his fellow-men. 
 
 THE END. 
 
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