Scale WQQ feet to an inch. 
 
AN 
 
 OUTLINE 
 
 
 MINERALOGY AND GEOLOGY, 
 
 INTENDED FSR THE USE OF THOSE 
 
 WHO MAY DESIRE TO BECOME ACQUAINTED WITH 
 
 THE 
 
 t 
 
 ELEMENTS OF THOSE SCIENCES ; 
 
 ESPECIALLY OF 
 
 YOUNG PERSONS. ; 
 
 ILLUSTRATED BY FOUR PLATES. 
 
 BY WILLIAM PHILLIPS, 
 
 MEMBEE rF TI!2 GEOLOGICAL SOCIETY. 
 
 NEW-YORK: 
 PRINTED AND SOLD BY COLLINS AND CO. 
 
 1816. 
 
EARTH 
 
 SCIENCES 
 LIBRARY 
 
PREFACE. 
 
 THE motive for introducing this little volume to 
 public notice, might seem to be wanting if it were 
 not avowed. It is this : There is no elementary 
 work on the subjects it embraces in our language; 
 no book that is calculated, by its simplicity and 
 freedom from theory, and from the shackles im- 
 posed upon a learner by the unnecessary use of 
 scientific terms, to invite his attention to the sci- 
 ences of Mineralogy and Geology. 
 
 It is not pretended that the following pages 
 have any claim to originality :. all the merit that 
 belongs to them, if indeed any should be allowed, 
 is that of combining in a narrow compass, an out- 
 line of sister sciences which merit a more general 
 attention than is given to them ; in an arrange- 
 ment as simple as the subjects will readily allow, 
 and in language which, it is hoped, will be intel- 
 ligible to those who may have no acquaintance 
 with them. 
 
 The form in which this outline is given, that of 
 a division into Lectures, though not absolutely 
 
 I1701S8 
 
ir ^ PREFACE. 
 
 novel, is not common. During the last winter 
 these Lectures were delivered at the neighbour- 
 ing village of Tottenham, in the order in which 
 they are now printed ; but with some deficiencies 
 supplied, and some errors corrected, that were in- 
 cidental to hasty compilation. These Lectures 
 were given gratuitously ; and the interest they 
 seemed to excite, in a numerous audience, prin- 
 cipally composed of young persons, and of both' 
 sexes, was felt as a flattering compensation. 
 
 But the form of Lectures is not adhered to on 
 that account alone. It allows of a familiarity not 
 inconsistent with an elementary treatise, while it 
 affords an opportunity for useful recapitulation, 
 that perhaps would appear objectionable in any 
 other form ; and for occasional repetition, which, 
 if the scientific should condescend to peruse it, 
 may seem tiresome, but will, I have no doubt, be 
 advantageous to the learner. 
 
 In a work, by far the greater part of which is 
 compilation, it may reasonably be expected that 
 authorities should be quoted. That has not al- 
 ways been done in its pages. I therefore here 
 acknowledge my obligation, in respect to the rni- 
 neralogical part, to Aikin's Dictionary of Chemis- 
 try and Mineralogy; and in the geological part, 
 to the Transactions of the Geological Society, to 
 Cuvier's Theory of the Earth, edited by Profes- 
 sor Jameson, to whose Geognosy I am scarcely 
 less indebted. These works are my principal au- 
 thorities 5 many others were occasionally consult- 
 
PREFACE. V 
 
 ed, but were not made use of in a degree that 
 seems to render their enumeration requisite. 
 
 If the perusal of this little volume should tend 
 to create in any person the desire for a knowledge 
 of the sciences on which it treats, beyond their 
 mere elements, it must be owned that it is dita- 
 eult to refer the reader to works in the English 
 language that are adapted to the use of the learner. 
 The only means by which a knowledge of mine- 
 ralogy can be acquired, is an acquaintance with 
 minerals : and I have no hesitation in recom- 
 mending those who may feel this laudable anxiety 
 for further information, in respect to these inte- 
 resting pursuits, to the acquirement of it by means 
 of small collections, which may be had of one 
 hundred varieties and upwards, with an arranged 
 catalogue, of Mawc, 149, in the Strand, at any 
 price between 5 and 100. One of these little 
 collections would materially assist the progress of 
 the learner ; more especially if accompanied by 
 a studious attention to the Manual of Mineralogy, 
 by Arthur Aikin, Secretary to the Geological 
 Society. The introduction to that work, forms a 
 valuable compendium of mineralogical informa- 
 tion : and though the learner will meet with many 
 terms and names that will demand explanation, 
 it may be said to be the only work in our lan- 
 guage that will be found of advantage to him, 
 The study of geology should follow that of mine- 
 ralogy. Small collections of rocks may also be 
 obtained. 
 
 A 2 
 
fl PREFACE. 
 
 The Geognosy of Jameson is altogether a sci- 
 entific work, not well adapted to the learner; in- 
 asmuch as a preponderating anxiety for the sup- 
 port of a favourite theory, has caused the intro- 
 duction of * many terms not hitherto adopted 
 by English mineralogists ; but much useful and 
 valuable geological information may be gleaned 
 from it. 
 
 W. P. ' 
 
 London, 1815, 
 
CONTENTS MINERALOGY. 
 
 Page 
 
 Preliminary observations ...... I 
 
 Objects of Mineralogy and Geology defined * . . 2 
 
 Of ELEMENTARY SUBSTANCES .'.... 3 
 
 Of Mineral substances ; simple and compound . . 4 
 
 Explanations of the terms acid and oxide (note) . . 
 
 OfAPFINITY 5 
 
 the cause of solidity in mineral bodies ... 6 
 
 the cause of crystallization or regular structure . 7 
 
 Fracture or cleavage of crystals in particular directions . 
 
 Definition of the term, Primitive crystal f . . . 8 
 
 The forms of PRIMITIVE CRYSTALS .... 
 
 viz. The Parallelepiped ...'... 
 
 Octohedron 9 
 
 Tetrahedron 10 
 
 Hexahedral prism ..... 
 
 Rhomboidal dodecahedron .. . . . n 
 
 Of the internal structure of crystallized minerals . . 
 
 Of measuring the angles of crystals the Goniometer . 13 
 
 Advantages of the reflecting goniometer ... 14 
 
 Of the NINE EARTHS 15 
 
 Three or four of them are metallic oxides ... 16 
 
 OfSilex 
 
 Alumine 17 
 
 Zircon 18 
 
 Glucine . 
 
 Yttria 19 
 
 Barytes _ 
 
 Strontian , . 30 
 
 lame ... . . . , 41 
 
 Magnesia , . 23 
 
Vlll CONTENTS MINERALOGY. 
 
 Pagfe 
 
 The Earths found in very different proportions . . 23 
 
 Of the two fixed ALKALIES 24 
 
 Of the Alkaline Earths .... 25 
 
 Of the Vegetable Alkali or Potash . . . 
 Of the Mineral Alkali or Soda ...... 
 
 The Alkalies have metallic bases, and are metallk oxides 26 
 
 Of the TWENTY-SEVEN METALS ... 29 
 
 Only seven metals known to the ancients . 
 
 General characters of the metals ... 
 
 Of the nature of metalliferous ores , . 30 
 Of the MALLEABLE METALS, 
 
 viz. Platina . . . . . . 3* 
 
 Gold ...... 3* 
 
 Silver ...... 34 
 
 Mercury or Quicksilver . . 35 
 
 Lead ... . . 36 
 
 Copper .... .38 
 
 Tin ... 39 
 
 Iron ...... 40 
 
 Zinc ... 4* 
 
 Palladium . . 43 
 Nickel . 
 
 Of the BKITTLE METALS, 
 
 viz. Arsenic ... 44 
 
 Antimony 45 
 
 Bismuth ...... 46 
 
 Cobalt .... . 
 
 Manganese . 47 
 
 Tellurium ..... 48 
 
 Titanium ..... 
 
 Tantalium . 4? 
 
 Molybdena ... 
 
 Tungsten 5 
 
 Chrome . 
 
 Osmium } ... 51 
 
 Indium 
 
 Rhodium . 
 
 Uranium . 
 
 Cerium 5 2 
 
CONTENTS GEOLOGT. IX 
 
 Page 
 Of COMBUSTIBLES . .... 52. 
 
 Of the two bases of Combustibles Carbon and Sulphur 53 
 
 List of Combustible substances, 
 viz. Sulphur ..... 
 
 The Diamond .....- 
 
 Mineral or Carbon Charcoal . . . 54 
 
 Plumbago or Graphite . 
 
 Mineral Oil (naptha and petroleum) . . J5 
 
 Bitumen Mineral or Pitch (maltha and asphalt) . 56 
 
 Coal (brown, black, and Cannel) . . 57 
 
 Blend or Kilkenny Coal, or Anthracite . jS 
 
 Jet, or Pitch Coal ~ 
 
 Amber ...... 
 
 Mellite, or Honey stone . . . . 59 
 
 CONTENTSGEOLOGY. 
 
 Of the objects of Geological inquiry . . 61 
 
 The ancients ignorant of Geology . . . 6a 
 
 Geology, very modern, as a science - 
 
 Hypotheses of Eurnet, Woodward, and others . . 
 
 More modern theories of Bertrand, Marschall, and Jameson 64 
 
 Of the theories relating to the agency of fire and water . 68 
 
 Principal tracts of low country . . . . 71 
 
 Strata of low and level countries are horizontal . . 73 
 
 Low and level countries contain sea-shells . . 
 
 Sea- shells found in hills far above the sea . . 
 
 And at the foot of great chains of mountains . . 73 
 
 Here, the strata are nearly vertical 
 
 Many catastrophes by the agency of water . . 74 
 
 Summits of lofty mountains contain no shells . . 
 
 And are therefore termed primitive , . 
 
 GEOLOGICAL POSITIONS ; . "5 
 
 Proofs that low and level countries contain organic remains 78 
 
 Strata of the Chalk basin of Paris described . 79 
 
 Strata of the Isle of Wight Chalk basin described 83 
 
 Strata of the London Chalk basin described . 84 
 
 The order of these strata is never inverted . 86 
 
X CONTENTS CEOLOtfT. 
 
 Page 
 
 Proofs that catastrophes by water have been extensive . 86 
 
 Bones of the rhinoceros, hippopotamus, elephant, abundant 88 
 Found only in alluvia] soil in low countries . 
 
 Never in rocks .....- 
 Account of the mammoth found in Siberia (note) 
 
 Additional proofs of the ex;: uv.veness of these catastrophes 90 
 
 Rock of Gibraltar encloses bones of the antelope and mouse 
 Bones of the ox, horse, ass, sheep, land shells, and serpents 
 
 in others . . . . 91 
 
 Proofs that organic remains are found in hills . . ^96 
 
 Cliffs of the Isle of Sheppey enclose fossil fruits, and 
 
 remains of animals .... 
 
 Beds of oyster shells near Reading, and in France, &c. 
 Remains of fish in Germany ... 97 
 
 Shells on the sides of Moinft JEtna . . 
 
 Proofs that shells are found at the foot of chains of mountains 98 
 Proofs that the strata, here, are nearly vertical . . loo 
 
 Rocks succeed each other in regular order . . 101 
 
 Secondary rocks known by the shells they enclose . 
 
 Proofs that the summits of lofty mountains contain no shells 
 Of the sumjnits of high mountains . . . loz 
 
 The nature and position of their masses . . 103 
 
 Are in their primitive state . . . 104 
 
 COMPARATIVE HEIGHTS OF MOUNTAINS . . 105 
 
 Division of rocks into primltii>e t transition, fstz, and alluvial 108 
 Primitive rocks are chemical deposites, contain no or- 
 ganic remains . . . . . 
 Transition rocks are both chemical and mechanical de- 
 
 posites, and contain organic remains . . 
 
 Difference between a chemical and a mechanical depo- 
 
 site (note) .....- 
 
 Flcetz rocks chiefly mechanical deposites, and contain 
 
 organic remains . . . .109 
 
 Alluvial rocks are mechanical deposites, and contain 
 
 organic remains . . . .no 
 
 Transition and flcetz, are by some termed secondary rocks 
 
 Werner's classification of rocks . . . na 
 
 List of Primitive rocks 
 
 List of Secondary, or Transition and Floetz rocks 113 
 
CONTENTS GEOLOGY. XI 
 
 Page 
 Werner's list of Alluvial deposites . . , 113 
 
 Section of the Brocken mountain described . . 
 
 Remarks on the strata of mountains . . . 115 
 
 Order in their deposition universally prevalent . .118 
 
 Of PRIMITIVE ROCKS, 
 viz. Granite . . . . ' |j| * ir ^ 
 
 Gneiss ...... 121 
 
 Micaceous schistus . . .123 
 
 Primitive limestone . . . .134 
 
 Primitive trap . . . . .126 
 
 Serpentine . . . . ^27 
 
 Porphyry . . . , .128 
 
 Sienite . . . . . > 1^9 
 
 Topaz rock . . . . .130 
 
 Primitive flinty slate 
 
 Primitive gypsum . \ , 
 
 White stone . . . . . 131 
 
 Other rocks are hy some added to those called primitive 
 
 Of TRANSITION, or the OLDER SECONDARY ROCKS . 133 
 viz. Transition limestone . . . . 
 
 Transition trap ..... 
 
 Greywacke ....... 
 
 Transition flinty slate .... 134 
 
 Of FLTTZ, or the NEWER SECONDARY ROCKS, 
 
 viz. Old red sandstone . . . , 
 
 First floetz limestone . , . ~ 
 
 First floetz gypsum . . , 
 
 Second, or variegated sandstone . . . 136 
 
 Second flcetz gypsum . . . . 
 
 Second flcetz, or shell limestone . 
 
 Third sandstone ....... 
 
 Rock salt formation . . , . 
 
 Chalk formation ....... 
 
 Flcetz trap formation ...... 
 
 Independent coal formation 
 
 Newest flcetz trap formation . . 
 
 Of ALLUVIAI DEPOSITES .,..-.. 
 
 Of organic remains in secondary rocks and alluvial deposites 138 
 
 V*It?S ..... 141 
 
XII CONTENTS GEOLOGY. 
 
 Of SALT DEPOSITES . . . . 
 
 Of COAL DEPOSITES ..... 160 
 
 Of VOLCANOES ..... 166 
 
 Of the DELUGE .... i*e 
 
 Of the INTERNAL STRUCTURE of the EARTH . . 18* 
 
 CONCLL'jDlN OBSERVATIONS .... iS 
 
 PLATES. 
 
 Comparative heights of Mountains 
 Forms of Primitive Crystals 
 Section of the Brocken Mountain 
 Veins in Tin Croft and Pink Mines 
 
LECTURE I. 
 
 Preliminary, Observations Objects of Mineralogy and Geology de- 
 finedElementary Substances Simple and Compound Minerals- 
 Affinity Crystallization Structure Primitive Crystals Of the 
 Earths -Of the Alkalies. 
 
 i. HE outline of the sciences of Mineralogy and 
 Geology, of which I am now about to endeavour 
 to give some idea, is not intended to involve all the 
 nicer inquiries, connected with the subject, that 
 have been instituted by scientific men. Nor do I 
 propose that this outline shall in any degree be 
 dependent upon, or connected with, the many 
 crude and almost barbarous theories of others, 
 who long amused and even dazzled the world 
 by the splendour of their inventions ; which ten- 
 ded to retard, rather than to forward an inquiry 
 into the nature of the globe we inhabit. 
 
 The phenomena presented by nature, arc wor- 
 thy of our notice ; to these your attention will be 
 principally invited. 
 
 Of the nature of the globe we comparatively 
 know but little ; our investigations are at the best 
 but superficial. For we know nothing but of what 
 appears on, or alove, or of what is brought to light 
 
by the descent of the miner beneath, the general 
 level of its surface ; but the miner rarely descends 
 more than 1500 feet, which is little more than 
 TTJ^dth part of the diameter of the earth. The 
 globe has often been said to resemble in shape, 
 an orange ; in allusion to that resemblance ; we 
 may therefore say, that we know nothing but of 
 the outer rind. 
 
 The greater number of mineral substances arc 
 to the generality of mankind only rude masses, 
 divested of instruction, and equally unintelligent 
 and unintelligible ; created only to minister to 
 our necessities. To some, it may be even difficult 
 to imagine how they should become the objects of 
 a distinct science, or that after the miner has 
 brought them to light, the naturalist should find an 
 interest in them previously to their being subjected 
 to the ingenuity of the artist. 
 
 The sciences of Mineralogy and Geology are, 
 however, worthy of our attention ; they will be 
 found to perform more than they seem to promise. 
 The more we know of them, the more of order, 
 of design, and of contrivance we shall perceive. 
 The power that created the whole is evident in 
 the smallest component part of the most eleva- 
 ted mountain. 
 
 Mineralogy has for its object the study of mi- 
 neral bodies 'm particular ; their characters, varie- 
 ttes, forms, and combinations. 
 
 Geology embraces the study of the earth in 
 j of its plain?, hills, and mountains, and of 
 
the relative positions of the masses of which they 
 are composed. 
 
 Geology comprises the 'study of rocks in the 
 mass ; Mineralogy, of the individual portions, or 
 substances which, by entering into combination, 
 form the mass. A knowledge of mineralogy is 
 therefore essential to the geologist, and for this 
 reason we shall begin with Mineralogy. 
 
 It was anciently supposed, under the dominion 
 of fancy and metaphysics, that all natural sub- 
 stances were ultimately resolvable into four simple 
 bodies, viz. air, fire, water, and earth, which 
 hence were called the four elements. The an- 
 cients however confessed that the precise natures 
 of the two first, air and fire, were not known to 
 them. They supposed most liquids to be modifi- 
 cations of the third element, water ; and that the 
 solid parts of the globe were attributable to the 
 last, that is, the element they called earth. Thus, 
 combustible bodies they supposed to contain a 
 combustible earth, and metals a metallic earth. 
 To modern chemistry however we are indebted 
 for a much larger catalogue of simple or elemen- 
 tary substances. It is now considered that there 
 are 9 earths, 2 alkalies, 27 metals, and 2 simple 
 substances, which may be considered as the bases 
 of those termed Combustibles ; and these elemen- 
 tary substances in the simple or compound state, 
 according to the present state of our knowledge, 
 form all the various constituent masses of the globe. 
 
A simple mineral substance* pure Gold for 
 instance, may be described as an unorganized 
 body, presenting an assemblage of lesser portions 
 of the same nature, united by the agency or force 
 of a natural law, to which I shall presently advert. 
 Compound mineral bodies are naturally found 
 in some instances simply aggregated, in others 
 chemically combined. When simply aggregated, 
 as for instance, when gold occurs in limestone, 
 their separation may be effected mechanically, by 
 pounding and washing : but when chemically com- 
 bined, as when silver occurs united with sulphur, 
 v.e must depend on the labours of the chemist 
 for their separation. 
 
 Some of the earths, the two alkalies, and some 
 of the metals, are naturally found combined with 
 various acids ^ 
 
 * A simple mineral substance may be chemically described as a i?ub- 
 , stance that lias wither been decomposed nor formed by art. 
 
 f Atmospheric, or common air, is composed of two very different 
 kinds of air, or gas, viz. oxygen gas, and azotic, or nitrogen gas, in the 
 proportion of 22 of the former to 78 of the latter. 
 
 Oxygen gas, being that part of common air which is essential to ani- 
 mal life, has been also called Vital Air : oxygen gas is composed of oxy- 
 gen united with- caloric, or the matter of heat, whence. oxygen is termed 
 the Jar's of Vital air. 
 
 When a substance is combined with a small proportion of con/gen, the 
 compound is called an oxide: when with a larger proportion, it is called 
 an acid, from the sour taste which most of these compounds possess; and 
 chemists have arranged with the arids some compounds which have not 
 been proved to contain oxygen, because their general resemblance to the 
 acids in other respects is sufficient to warrant the opinion that the sinw- 
 Inniy hold* in this particular also. 
 
Some of the metals are also found in combina- 
 tion with oxygen which is the basis of vital air ; 
 they are then termed oxides of those metals ; and 
 in that state (to use a familiar illustration) bear 
 the same affinity to those metals, as rust does 
 to iron ; rust being the consequence of the ab- 
 sorption by iron, of oxygen from atmospheric air. 
 This chemical combination with oxygen causes 
 metals to assume appearances quite different to the 
 same metals in the pure state ; as for instance, 
 the red oxide of copper, is of a ruby red colour, 
 and frequently almost transparent, and the oxide 
 of tin when pure, is nearly colourless and trans- 
 parent. To show the liability of mineral bodies 
 to become compound, it may be quoted that the 
 ore called white silver, is composed of four metals, 
 silver, lead, antimony, iron ; two earths, alumine 
 and silex ; and one combustible, viz. sulphur. 
 
 Water is however found to enter more or less 
 into the composition of some mineral bodies, and 
 it is termed the water of crystallization when 
 these substances possess a regular structure. 
 
 The law to which an allusion was just now 
 made, as being that to which are subject the ele- 
 mentary substances, of which the masses consti- 
 tuting the globe are composed, is called Affinity. 
 
 When Oxygen 5? coaihined vrith i.cn, the compound is termed oxide 
 
 cf iro.i : Oxygea by combining with a certain proportion of carbon or 
 
 cliarco^], forms an nekl, called the carbonic ?cid : which, united v:i!h 
 
 . oiind mineral caller! caibonnte of limn, cf which one 
 
 vii.it-;>- is limestone, and another is chalk. 
 
 B 2 
 
6 
 
 This law may be said to involve in it, all those 
 termed attraction, gravitation, magnetism, and 
 electricity. To the law of affinity, mineral bodies 
 owe their existence in separate and similar mas- 
 ses ; as well as their regular crystalline forms ; 
 and but for this important law of nature, the solid 
 parts of the globe would only have been a chaotic 
 mas?, instead of exhibiting, even in the oldest 
 rocks, deposites of distinct substances frequently 
 in regular crystalline forms. 
 
 Before we proceed to consider the natures of the 
 several simple bodies just alluded to, either sepa- 
 rately, or as entering prominently into combina- 
 tion in certain mineral substances, I shall invite 
 your attention to that consequence of the law of 
 affinity, which is termed Crystallization. It seems 
 necessary here to introduce this part of our in- 
 quiry, because in speaking of earthy and metalli- 
 ferous substances, I shall present to your notice 
 specimens, some of which exhibit those bodies in 
 their natural crystalline forms. This subject, 
 when considered at large, is curious and interest- 
 ing ; its investigation, keeping pace with other 
 rapid advances in science, has of late been digni- 
 fied by the adaptation of geometry and algebra 
 to its illustration. In the narrow compass of 
 what I have undertaken, it is impossible to give 
 more than a very limited view of the subject, 
 but I shall endeavour to make its general outline 
 understood, avoiding, on this, as on all other occa> 
 
sions, as much as possible, all technical or scien- 
 tific terms. 
 
 The term Crystal, is derived from the Greek 
 Kf t/s-^AAos (Crustallos,) signifying ice, which was so 
 called on account of the ease with which it liqui- 
 fied. The term crystal was afterwards applied 
 to what is now called Rock crystal, by the Roman 
 naturalists, and supposing it, both from its trans- 
 parency and beautiful symmetrical forms, to be 
 only water indurated by continued frosts in the 
 mountainous regions of the Alps. But finding 
 that certain salts also took a prismatic form, the 
 term crystal assumed a more general meaning, and 
 now includes all the regular, many-sided solids, 
 whether of earthy or metalliferous substances, 
 presented either by nature or chemistry. 
 
 There are comparatively very few substances 
 that are. not found naturally crystallized with 
 more or less regularity. The forms assumed by 
 some are very numerous and highly interesting. 
 For instance, the carbonate of lime has been 
 found in about 300, and the oxide of tin in about 
 180 varieties of form : and as of both these, as 
 well as most other substances, the crystals may 
 be broken in particular directions, the true defi- 
 nition of a crystal seems to be this, that it has 
 not only a regular external figure, but also a re- 
 gular internal structure. This structure in the 
 crystals of several minerals, is readily exemplified 
 by mechanical means, producing fractures, or 
 cleavages of perfect regularity. Some, even small 
 
crystals, have been found exhibiting upwards of 
 150 little planes; but as most crystals can be 
 broken in particular directions, we are enabled 
 to trace these complicated forms through their 
 many intermediate varieties, into one simple form, 
 which therefore is termed the primitive crystal of 
 that substance. The crystals of many minerals 
 assume the same figures, and therefore are readily 
 traced to the same primitive form. If we take 
 into consideration the whole range of substances 
 found in a crystallized state, the primitive forms 
 of their crystals, numerous, varied, and compli- 
 cated as many of them are, may be said to be com- 
 prehended in the five following solids ; see plate 2. 
 The Parallelepiped, 
 
 Octohedron, 
 
 Tetrahedron, 
 
 Hexahedral prism, 
 
 Rhomboklal dodecahedron. 
 The Faralkloplpedm&ybe said to comprehend 
 every solid contained under six parallelograms : 
 that is, under six planes, whose bounding lines 
 two and two are parallel with each other, and 
 whose opposite sides are equal and parallel. Of 
 these solids, the cube and the rhomboid are se- 
 lected as the most common : there are also others 
 more or less allied to these. The cube is a body 
 of perfect proportion ; all its sides are equal all 
 its planes are square. The primitive forms of 
 some substances are much flatter than the cube ; 
 of others, they are much higher : these are then 
 
fiimitwe O stats 
 
 Octohtdron, 
 
 jpfcxaAcdral prism 
 
 Jthoriibotdal Dodecahedron 
 
termed sqvare prisms. The rhomboid differs from 
 the cube essentially ; none of its planes are square, 
 but they resemble each other; two of the opposed 
 angles of each plane are more obtuse, the- other 
 two are more acute, thfcn those of the planes of 
 the cube. Of rhomboids there are several varie- 
 ties; that is, the angles of their planes are more 
 or less acute and obtuse : these rhomboids there- 
 fore differ in aT greater or less degree from the 
 proportions of the cube. There are some other 
 varieties of the paTallelopiped which it does not 
 seem essential to our present object to explain. 
 
 Of the Octahedron also there are several varie- 
 ties : three of the most obvious are selected. 
 The regular o&ohedron, is so called, because it 
 is a solid contained under eight planes, each of 
 which is ja triangle equal and similar to each of 
 the others ; and which, having all its three sides 
 of the same length, is therefore termed an equi- 
 lateral triangle. A line drawn from its summit 
 to its lowest extremity or angle, is precisely 
 of the same length PS a line from any other of its 
 angles to its opposite angle. As the primitive 
 crystal of some substances, is found an octahe- 
 dron, much flatter than the regular, and therefore 
 called an obtuse octohedron : two of the three 
 lines, bounding each of its eight triangles, are 
 shorter than the third. A line drawn from the 
 summit to its lower extremity or angle is shorter 
 than a line from any of its other angles to its op- 
 posed angle. An octohedron is found to be the 
 
10 
 
 primitive crystal of some substances which is 
 much longer than the regular octahedron, and is 
 is called acute, because its upper and lower angles 
 are more sharp or acute than the other four angles. 
 Two of the three lines bounding each of its eight 
 triangles, are longer than the third ; and a line 
 drawn from the upper to the lower extremity or 
 angle, is much longer than one drawn from either 
 of its other angles, to the opposed angle. 
 
 Of the octahedron there are some other varie- 
 ties, of which It does not seem now requisite to 
 enter into an explanation. 
 
 The Tetrahedron is a solid comprehended with- 
 in four planes, each of which is a triangle equal 
 and similar to the rest, having each of its three 
 sides of the same length. It is the simplest of 
 all the primitive forms. 
 
 The Hexahedral prism is a solid comprehended 
 within eight planes, which are not all similar. 
 Its upper and lower planes, called the terminal 
 planes, are alike, being six-sided or hexagonal : 
 each of the sis sides being of the same length. 
 The other six planes, which are called the lateral 
 planes, are alike in regard to each other, and in 
 the figure in plate 2, are each perfectly square. 
 This is not always the case in primitive crystals ; 
 in some, the lateral planes are much longer, in 
 others shorter ; in either of which cases the planes 
 would not be square, but oblong. Hexahedral 
 prisms, as primitive crystals, are therefore of 
 various lengths. 
 
11 
 
 The Rhomloidal dodecahedron is a solid com- 
 prehended within twelve planes, all of which arc 
 perfectly alike in form ; each plane boing a rhomb, 
 of which the four bounding lines are all equal in 
 length, and are parallel ^two and two, forming 
 two acute and two obtuse angles on each plane. 
 
 But, certain substances are naturally found to 
 assume two of those, which are termed primitive 
 forms. Amoagst Vhese is the fluate of lime ; it 
 therefore becomes a question which of the two, is 
 the true primitive form of that substance. This 
 question is decided by the internal structure of the 
 crystal ; if we take a crystal of it in the form of 
 the cube, we shall find that all its corners, termed 
 the solid angles, may be regularly broken off, so 
 as to produce in lieu of each of them, a regular 
 triangular plane, and that, by pursuing this frac- 
 ture, we shall finally arrive at a form which in 
 fact is the regular octohedron, which therefore is 
 proved to be the primitive form of the fluate of 
 lime ; of which, it is also proved, that the cube is 
 only a secondary crystal, the result of an aggre- 
 gation of laminae on the several planes of the 
 octohedron ; in other words, by the addition of 
 laminae, or regular lay ers, parallel with the planes 
 that may be obtained by mechanical cleavage. 
 
 If however we take a similar crystal, that is, a 
 cube, of common salt, we shall find that it is not 
 the result of the same law of crystallization 5 that 
 is, we shall find that it cannot be fractured in the 
 same way, the corners or angles cannot be taken 
 
12 
 
 /f, and as it can be fractured only in the direction 
 <$ or parallel with the six faces of the cube; that 
 solid is therefore esteemed to be the primitive 
 form of common or rock salt. But by adding 
 regular layers parallel with the planes obtainable 
 by mechanical cleavage, that is, on the six planes 
 of the cube of rock salt, we should never obtain 
 an octohedron; accordingly rock salt is never 
 found crystallized in the form of the octohedron. 
 The carbonate of lime is always readily broken 
 into Rhomboids, and no other form. 
 
 The crystals of the fiuate and the carbonate of 
 lime, and of common salt, are quoted as remark- 
 able instances of the ease with which their natural 
 structure affords mechanical cleavage; but, all 
 mineral substances are not fractured with the 
 same ease. The topaz can only be readily cleaved 
 in one direction; and quartz or rock crystal, 
 though sometimes it presents indications of its real 
 structure, has never yet been regularly fractured. 
 This diversity in the structure of crystallized 
 bodies has not been satisfactorily explained ; we 
 only know the fact. 
 
 It has already been said that the mineralogist 
 depends on the internal structure, for a knowledge 
 of primitive forms ; but where the knowledge of 
 this structure cannot be attained by mechanical 
 means, recourse must be had to other means : 
 analogy seems the only resource. In other words, 
 a comparison of the external forms of such crystals 
 as do not admit of s* mechanical cleavage, witk 
 
the external forms of the crystals that do admit 
 of it; but this is sometimes the source of error. 
 
 It may readily be supposed that the regular 
 internal structure so observable in the crystals of 
 many substances, would necessarily produce a 
 regular external form. This actually exists in a 
 degree scarcely credible by those who have not 
 examined the subject, both in those crystals of 
 which the internal structure is known, as well as 
 in those of which it is not. 
 
 Much attention has lately been given to ascer- 
 tain precisely, the angles at which the various and 
 even numerous planes of crystals meet each other 
 For this purpose an instrument has been invented, 
 called the goniometer, meaning the measurer of 
 angles ; but we may conclude that its use scarcely 
 admits of perfect accuracy ; and for this reason, 
 the few most conversant in its use, have differed 
 in the results obtained from the same substances. 
 
 Another instrument has lately been invented by 
 Dr. Woliaston, called the reflecting goniometer, 
 because its use depends on the reflections to be 
 observed upon the natural polish on the planes of 
 crystals. This instrument has already done service 
 to science in detecting some fallacies, arising from 
 a reliance on the former instrument. 
 
 When once the angles of the primitive crystal 
 of any substance are accurately ascertained, the 
 angle at which any two of its numerous planes 
 meet, is calculated with wonderful precision by 
 the assistance of geometry. 
 
 c 
 
14 
 
 The angles formed by the meeting of any two 
 planes of each of the five regular solids, the cube, 
 the regular octohedron, the tetrahedron, the hex- 
 ahedral prism, and the rhomboidal dodecahedron, 
 already enumerated among primitive crystals, are 
 known, because they all are regular geometrical 
 solids. But it has already been shown, that there 
 exist as primitive crystals, varieties of the parallele- 
 piped and of the octohedron, which differ from each 
 other both in shape and measurement. As n- 
 stances; the primitive crystal of quartz, is a 
 rhomboid very different to that of carbonate of 
 lime, and much more nearly approaches the cube. 
 The primitive crystals of the oxyd of tin and of 
 zircon, are octohedrons, differing from each other, 
 but are much more flat than the regular octohe- 
 dron, while the octohedron which is the primitive 
 crystal of sulphur, is much longer and more acute. 
 The primitive crystal of the cyanite is a four-sided 
 and oblique prism, with rhombic terminations, 
 while that of the sulphate of barytes is a four- 
 sided rhomboidal prism also with rhombic termina- 
 tions. The difficulty therefore is, to obtain the 
 precise admeasurements of those primitive crystals, 
 which are not regular geometrical solids. It is 
 probable that the reflecting goniometer of Dr. 
 Wollaston will discover, that the principal part 
 of the calculations hitherto made, in regard to 
 the angles of such primitive crystals, and of 
 the numerous facets to be observed on them, 
 (which not belonging to the primitive crystals, are 
 
JS 
 
 therefore termed secondary planes,} are incorrect ; 
 and for this reason ; this goniometer will assist 
 in measuring the angles of crystals as small as 
 the head of the smallest pin, if their planes be per- 
 fectly brilliant; and it is ascertained that minute 
 ci-ystals are always more perfectly formed than 
 large ones. Now the calculations already alluded 
 to are grounded upon measurements taken by the 
 common goniometer upon large crystals, the planes 
 of which rarely are perfectly formed and smooth : 
 even such as have brilliant planes, and seem there- 
 fore adapted to the use of the reflecting gonio- 
 meter, seldom afford similar results. 
 
 I shall now offer to your notice some obser- 
 vations on those elementary substances termed 
 simple or pure earths, which are nine in number: 
 they are called 
 
 1. Silex 6. Barytes 
 
 2. Alumine 7. Strontian 
 
 3. Zircon 8. Lime 
 
 4. Glucine 9. Magnesia 
 
 5. Yttria 
 
 All these earths agree, when free of foreign 
 admixtures, in this one character, they are all 
 mow-white. 
 
 Although these substances by common consent 
 are called simple or pure earths, it seems essential, 
 in speaking of them as elementary substances, to 
 say that chemistry, which, during the last twenty 
 years has made amazing progress, has by the late 
 brilliant discoveries of Sir Humphrey Davy, 
 
completely turned the tables on the ancients. 
 They supposed that every metal had an earthy 
 basis, whereas his experiments have decisively 
 shown, that three if not four of the earths have a 
 metallic basis ; that, in fact, they are not simple 
 substances, but compounds, consisting of metallic 
 bases united with oxygen ; and, to use the same 
 familiar illustration as before, these four earths 
 have the same affinity to their respective metallic 
 bases as rust has to iron; they are metallic oxides. 
 The four earths are those called silex, alumine, 
 lime and barytes, but the basis of alumine is not 
 so decidedly ascertained as the bases of the other 
 three. Strictly therefore we ought to diminish the 
 number of earths, by the three or four in question, 
 and to increase the number of metals ; but, as dis- 
 coveries, however brilliant and however well 
 established, are rarely admitted with instantane- 
 ous consent, these metallic oxides are still suffered 
 to hold their places as earths. 
 
 I now proceed to give some account of each 
 earth separately, and shall offer to your inspection 
 some specimens of substances in which they pro- 
 minently enter into combination. 
 
 The first on the list is SJLEX. This is one of 
 those earths which the discoveries of Sir II. 
 Davy have decidedly shown to have a metallic 
 basis, which he has called Silicium, and being the 
 result of a combination of oxygen with that metal, 
 is therefore a metallic oxide. Silex, in its pure 
 state, is not three times as heavy as water, and 
 has neither taste nor smell. 
 
17 
 
 As common flints are almost wholly composed 
 of siliceous earth, it has from that circumstance 
 received the name of Silex t which in Latin signi- 
 fies Flint ; but this earth is found in greater purity 
 in opal, and in quartz, or rock crystal.* Silex is 
 probably the earth which most abundantly enters 
 into the composition of the globe. 
 
 Silex enters largely as a component part of 
 glass, for which 'purpose the pure sand from some 
 parts of the coast of Norfolk, and Alum Bay in 
 the Isle of Wight, are preferred. It has never 
 been found combined with an acid. 
 
 ALUMINE has been so called from its forming 
 the basis of common alum. When pure, it has 
 neither taste nor smell, and is twice as heavy as 
 water. Though one of the most extensively dif- 
 fused substances, it is nowhere found pure ; and 
 though a constituent part of the purest clays, it 
 rarely forms more than one-fourth or one-third 
 part of them ; it is however found nearly pure in 
 the oriental. ruby and the sapphire, and in corun- 
 dum, which are the next in hardness to the 
 diamond/)- Alumme forms a large proportion of 
 that valuable mineral called fullers' earth, which 
 has that smell when breathed on, peculiar to 
 
 * Quarts Is composed of i!ex, with '2 or 3 parts in the 100 of water. 
 Of.il, of JiO parts of ?iiex and 10 of water. Flint, of 97 parts of siiex, 
 3 of nlirniiieand oxide of iron, and 2 of - 
 
 - * i'v Wr yields about US parts of alnmine, 1 of ox- 
 
 il!o OI ' 'n-all portion of lime; Iho O.-knM Rufiy, 00 parts 
 
 of alumihe, 7 *Hev, and soin^ oxide of iron : Corundum, about 80 parts 
 of alumiue, 5 of sikx, and nearly 2 of oxide of iron 
 
 C 2 
 
 
 
18 
 
 clayey substances, and which forms a mineralogi- 
 cal test of the presence of alumine. 
 
 In useful purposes, alumine enters largely into 
 the composition of bricks, pottery, and porcelain ; 
 it is infusible. The experiments of Sir H. Davy 
 have rendered it probable, that alumine is a 
 metallic oxide, having a metallic basis, which he 
 has called aluminum. 
 
 ZIRCON when pure, is rough to the touch, in- 
 sipid, and insoluble in water ; it is found combined 
 with other substances in the hyacinth, from a 
 brook called Expailly, in Auvergne in France ; 
 and in the jargoon from Ceylon.* Hitherto zircon 
 has not been put to any useful purpose ; it is 
 about four times as heavy as water. 
 
 The earth called GLUCINE obtained that name 
 from the Greek yAwco*, signifying sweet, on account 
 of the sweet taste by which- its salts are distin- 
 guished. When pure, glucine is a white pow- 
 der, soft, and somewhat unctuous to the touch, 
 and is nearly three times the weight of water. 
 
 In the natural state glucine has hitherto only 
 been found in the beryl and the emerald ;f but 
 neither the pure earth nor any of its salts, have 
 hitherto been applied to any use. 
 
 * The Hyacinth is composed of 70 parts of zircon, 25 of silex, and 
 a iraoe of oxide of iron. Jargoon 66 parts of zircon, 31 of silex, and 2 
 of oxide of iron. 
 
 f The Emerald i.s composed of about 64 parts of silex, 16 of a!u- 
 *une, 13 of gucinc, 1 of lime, and nearly 4 of oride of chrome. 
 
19 
 
 YTTIUA, in many of its properties and appear- 
 ances in its pure state, bears considerable affinity 
 to glucirie. it has the same saccharine taste, but is 
 easily distinguished from it, inasmuch as it is 
 nearly five times heavier than water, and by 
 some properties discoverable only by the chemist. 
 
 In the natural state, yttria occurs as a com- 
 ponent part of a mineral substance called the 
 gadolinite,* which is brought only from Sweden, 
 and which was so called on account of its having 
 been first analysed by the Swedish professor 
 Gadolin, who named the earth yttria, because the 
 mineral in which it was discovered, was brought 
 from Ytterby in Sweden. 
 
 BARYTES has never been found pure in the 
 natural state, but always combined, either with 
 the sulphuric acid forming sulphate of barytes or 
 heavy-spar; or with the carbonic acid forming 
 carbonate of barytes, or witherite.f Barytes and 
 all its salts, except one, are violent and certain 
 poisons, destroying animals by inflaming the in- 
 testines, and are often used for the destruction of 
 vermin. Barytes is one of the earths that have 
 lately been discovered by Sir II. Davy to have a 
 metallic basis. This basis, he has called Barium, 
 
 * The Gadolirdte is composed of about 56 parts of yttria, with a trace 
 of manganese, 22 of siler, 5 of glucine, 17 of oxide of iron, a small por- 
 tion of alimiiae and rome water. 
 
 f The WitheiHe Is composed of 73 parts of baryta and 22 of car- 
 bonic acid. Heavy Spar is composed of 87 pails of barytes and 33 of 
 sulphuric ?cid. 
 

 20 
 
 which uniting with a certain proportion of oxygen, 
 forms barytes. 
 
 STRONTIAN has never been found in a pure 
 state. It was first brought, combined with the 
 carbonic acid, from a place in Argyleshire called 
 Strontian, whence the mineral obtained its familiar 
 name of strontianite. Strontian, combined with 
 the sulphuric acid, is found near Bristol ; thus 
 combined, the mineral substance has obtained the 
 name of ccelestine,* from its delicate tint of a light 
 blue colour. 
 
 The earth called strontian, either when pure or 
 combined with the acids above mentioned, has 
 not hitherto been applied to any use. At present 
 therefore these combinations merely serve to 
 form a part of a mineralogical collection. 
 
 LIME has never yet been found in a pure state, 
 but when so prepared by the chemist, is mode- 
 rately hard, and of a hot acrid taste. It has 
 been proved by Sir H. Davy to have a metallic 
 basis which he calls Calcium : lime is therefore a 
 metallic oxide. Lime naturally occurs in com- 
 bination with the carbonic^ sulphuric, boracie,Jtuo- 
 ric, and phosphoric acids. 
 
 Lime, combined with the carbonic acid forms a 
 mineral substance, thence termed carbonate of 
 lirne.f A variety of this mineral is to be found in 
 
 * The S'ronliam'e i cnijifcsefl of about 60 pnrt. of jtrontian, 30 of 
 enrhonic acid nnd a little wfriwr Ca.ksiine, of 54 parts of strontian, and 
 48 of sulphuric acid. 
 
 f Calcareous Spar, or carbonate of ihne, is composed of 57 parts of iimr, 
 ml 43 of carbonic acid. 
 
21 
 
 the cabinets of mineralogists, in a vast number of 
 beautiful forms, all of which may be traced to the 
 rhomboid, which there fore is termed the primitive 
 crystal. Those minerals commonly called lime- 
 stones, and chalk, and marble, are also carbonates 
 of lime. The uses to which lime is applied, 
 (when the carbonic acid with which it is combined, 
 as forming chalk and limestone, is driven off by 
 heat) are well known. The rocks on each side the 
 Avon near Bristol, are of a peculiar kind of lime- 
 stone, which has obtained the name of swine-stone, 
 from its yielding when rubbed a fetid smell. This 
 smell is attributed to the presence of bitumen, 
 the nature of which will be mentioned among the 
 combustibles. 
 
 Lime, in combination with the -sulphuric acid, 
 is called sulphate of lime, or familiarly gypsum.* 
 Of this mineral the uses are very extensive. 
 When compact, it is called alabaster, and is em- 
 ployed by the architect for columns and other 
 ornaments, being more easily worked than marble ; 
 it is also turned by the lathe into cups, basins, 
 vases, and other similar articles. When sulphate 
 of lime or gypsum, is subjected to a certain heat, 
 it loses what is termed its water of crystallization, 
 and is converted into a fine powder called plaster 
 of pans; the uses of which, when beaten up with 
 water into a paste, for taking casts of gems and 
 sfatues, are well known. 
 
 * Gypsum is composed of about 32 parts of lime, 46 of sulphuric 
 acid, and 2t of witur. 
 
Lime, combined with the arsenic acid, forms a 
 mineral called Pharmacolite ;* the only species : 
 with the boracic acid, a mineral is formed called 
 the datholile.f 
 
 Lime, combined with the jflworic acid, is called 
 fiuate of lime. This mineral is commonly known 
 by the name of fluor spar jj in Derbyshire, as blue 
 John. The elegant vases and chimney ornaments 
 turned by the lathe out of blocks of this substance, 
 are known to almost every one ; the brown colour 
 generally observable in these vases is obtained by 
 exposure to heat. Fiuate of lime is extensively 
 used in smelting the ores of copper. 
 
 The mineralogist values the fiuate of lime for 
 its abundant and beautiful variety of crystals, both 
 in form and colour : all the forms it assumes may 
 be traced to the regular octohedron, which there- 
 fore is termed the primitive form of its crystal. 
 The octohedron may be obtained from each of 
 them, however unlike to it,by breaking it in certain 
 directions. 
 
 A variety of fluate of lime, called chlorophane, 
 found in Siberia and Cornwall, on being exposed 
 to the heat of a live coal, gives out a beautiful 
 green light. 
 
 * The Pharmacoliie 5s composed of about 46 parts of arsenic acid, 23 of 
 lime, 6 ofsilex, 22 of water, and a small portion of oxide of cobalt. 
 
 f The Dniholile is composed of abeut 36 parts of lime, 36 of silex, 24 of 
 boracic acid, and 4 of water. 
 
 $ Fluor Spar, or the fiuate of lime, yields by analysis about 68 parts 0f 
 lime and 32 of fluoric acid. 
 
23 . 
 
 Lime, in combination with the phosphoric acid, 
 forms a mineral which occurs in small crystals, 
 called apatite* or phosphate of lime. 
 
 MAGNESIA is a light earth of a perfect white- 
 ness, and is absolutely insipid ; the slightly acrid 
 taste occasionally to be found in the magnesia 
 used in medicine, arises from a proportion of lime. 
 Naturally, magnesia occurs combined with the 5o- 
 racic acid, in the borate of magnesia, or boracite.f 
 
 In the rare mineral by some called native mag- 
 nesia, analysis has proved it to be combined with 
 the sulphuric and carbonic acids. 
 
 Magnesia is one of the least abundant substan- 
 ces ; it does not enter into the composition of many 
 mineral bodies, but it forms a small proportion of 
 that substance called the soap-stone, which owes 
 its greasy or soapy feel to magnesia. The soap- 
 stone is largely employed in the manufactory of 
 porcelain. 
 
 "These nine earths enter, in very different pro- 
 portions, into the composition of the globe. 
 
 It is considered that silex is the most abundant 
 of all. It forms the greatest ingredient of the 
 oldest rocks, is largely found in others, and in 
 
 * Apatite yields 55 of lime and 45 of phosphoric acid. 
 
 f The Boradts is composed of about 17 parts of magnesia and 83 of the 
 boracic acid. The Spindle. Ruby, about 85 parts of aluaiine, 9 of magnesia, 
 of chronic acid. Asbestus, 59 parts of silex, 25 cf amnesia, 9 of iime, 
 3 of aluinine- The Soap-stone, of about 59 [wrt* of siiex, 30 of magnesia, 
 2 oxide of iron, and ti 31 waf.vr. 
 
24 
 
 clays and soils in these, aluinine is the next in 
 abundance : to it succeeds lime, which is less 
 common in primitive rocks, though very plentiful 
 in the transition and flcstz, or secondary rocks. 
 
 Magnesia and barytes occur in comparatively 
 rery small quantities. The first enters but little 
 into the composition of rocks and soils ; the latter 
 rarely. 
 
 Strontiari, zircon, glucine, and yttria, are very 
 sparingly found ; the first may be said to be the 
 most common of the four, the others are only found 
 in part,the components of a few mineral substances, 
 some of which are occasionally enclosed in rocks ; 
 but rarely does any one of these four earths enter 
 into the composition of rocks or of soils. 
 
 Barytes, magnesia, strontian, and lime, are never 
 found pure ; but mostly combined with acids. 
 
 We now proceed to those mineral substances 
 termed ALKALIES, which enter into the com- 
 position of several minerals. 
 
 The term Jllkali is Arabic, and is expressive cf 
 the acrid saline residue left in the ashes of the 
 plant called Kali, after its combustion in the open 
 air; and, not being volatile, was termed Fixed 
 Alkali. 
 
 FixKJ) ALKALIES are usually denominated of 
 two kinds. The Vegetable or Potash, and the 
 Mineral or Soda. L'otash is procured from the 
 ashes of vegetables in general not growing con- 
 tiguous to the sea. Soda is the basis of common 
 
salt, and is therefore found in immense quanti- 
 ties ; it is also the principal saline residue of 
 plants growing on the sea shore. 
 
 The taste of the pure fixed alkalies, is acrid, 
 burning, and nauseous ; they are without smell ; 
 they have peculiar chemical properties, which it is 
 not my province to describe ; but it is important 
 to say that the. earths called barytes, strontian, 
 lime, and magnesia, agree so nearly with the 
 alkalies, in some of their chemical properties, that 
 some chemists have given them a place among the 
 alkalies, others have termed them alkaline earths. 
 
 POTASH occurs in the natural state in the 
 leucite, and in mica, and in several other sub- 
 stances 5 therefore the term vegetable, as applied 
 to potash, is not absolutely correct.* 
 
 SODA is found naturally combined with the 
 carbonic acid, forming carbonate of soda, and 
 with the muriatic acid, forming muriate of soda 
 or common salt.f 
 
 The mineral substance called fettsteiu, yields^ 
 by analysis, both potash and soda.J 
 
 Both potash and soda are largely employed in 
 the making of glass and soaps. When pure, they 
 
 ' The Lcuciie yields, by analysis, about 54 parts of wlex, 25 of alc- 
 arine, and 21 of potash. 
 
 f The water of the ocean contains from one twenty-fifth to one- 
 Unity-fifth of its weight of muriate of soda or common salt, which i? 
 ':owpo*ed of 53 parts of sod^ 47 of the muriatic acid. 
 
 f The Fettstdn, 44 eilex, 34 alumine, 4 oxide of iron, a pura!! r>o- - 
 ^ion of lime, and about 1C parts of sodn ami potash.. 
 J> 
 
are not easily distinguished from each other, but 
 potash is the heaviest. Until lately, both po.tash 
 and so^a were believed to be simple substances 5 
 but, by the experiments conducted by Sir H. Davy, 
 with the astonishing powers of electro-chemical 
 agency, they have both, as well as the four earths 
 already noticed, been actually decomposed. The 
 mode by which this was effected is highly inge- 
 nious and interesting; the detail belongs to the 
 r hemist. The result, however, was, that potash 
 was found to be a combination of oxygen with a 
 wetal, exactly resembling quicksilver in appear- 
 ance, and which, by the discoverer, has been call- 
 ed 1'otassium, as being the basis of potash. The 
 result was exactly similar in regard to soda, the 
 metallic basis of which he called Sodium. Both 
 potash and soda, therefore, are metallic oxides. 
 Both of the metals, Sodium and Potassium, are 
 malleable ; in this respect, agreeing in character 
 with iron, copper, and some other metals. 
 
 The same observation that has been-made in 
 regard to the four earths, which have metallic 
 bases, viz. that tfceir bases properly belong to the 
 metals, will also apply to potassium and sodium, 
 but potash and soda still hold their rank as fixed 
 alkalies. 
 
 It is by no means improbable, that future re- 
 searches in chemistry, will also discover the bases 
 of the remaining five substances yet considered as 
 earths, and that, by common consent, both the 
 
21 
 
 earths and the fixed alkalies will be swept away, 
 and their bases added to the catalogue of metals. 
 The discoveries just noticed have been effected 
 by the aid of galvanism superadded to chemistry. 
 Galvanism, or electricity, therefore, (for a doubt of 
 their identity scarcely exists) holds a high and 
 important station in science. With such aid, 
 chemical e.xperjment, conducted by such men ns 
 Sir H. Davy, and other able chemists of the 
 present day, may work a complete reformation 
 in science : it is impossible even to conjecture 
 /here discovery will stop. 
 
LECTURE II. 
 
 Of the Metals -Of Combustibles. 
 
 ON a former evening it was said that mineral 
 Sodies are considered to be of four kinds, EARTHS, 
 ALKALIES, METALS, and COMBUSTIBLES. 
 
 That they are naturally found either simple oc 
 compound ; the simple consisting of one substance 
 alone, the compound of two or more, and that 
 these are either mechanically or chemically com- 
 bined. 
 
 That some of the earths and metals are found 
 combined with various acids, and some of the 
 metals with oxygen, or the basis of vital air. 
 
 It was also said that, by the aid of chemistry, 
 nine earths had been discovered, and two fixed 
 alkalies ; but that Sir Humphrey Davy, by the 
 assistance of electro-chemical agency, had lately 
 proved that three or four of those substances 
 called pure earths, as well as both the fixed 
 alkalies, have, in fact, metallic bases ; and that 
 they consist of oxygen in combination with those 
 bases. 
 
 Having also, in the former evening, considered 
 some of the properties and uses of the earths and 
 alkalies,we shall now proceed to notice the metallic 
 bodies, and afterwards those called combustibles-. 
 
The only metals known to the ancients were 
 gold, silver, copper, iron, tin, lead, and mercury ; 
 but discoveries have from time to time increased 
 the catalogue, until it has been swelled to the 
 number of twenty-seven, independently of those 
 which have very lately been discovered as the 
 bases of four of the earths and the two alkalies. 
 
 Of these metals, the first eleven only have the 
 important property of malleability, or of being 
 sufficiently tenacious to bear the extension of their 
 body by beating with the hammer 5 the others 
 have by some been therefore termed brittle metals, 
 
 Malleable Metals. 
 
 Brittle 
 
 Metals. 
 
 Platina, 
 
 Arsenic, 
 
 Molybdena, 
 
 Gold, 
 
 Antimony, 
 
 Tungsten, 
 
 Silver, 
 
 Bismuth, 
 
 Chrome, 
 
 Mercury, 
 
 Cobalt, 
 
 Osmium 3 
 
 Lead, 
 
 Manganese, 
 
 Iridium, 
 
 Copper, 
 
 Tellurium, 
 
 Rhodium, 
 
 Tin, 
 
 Titanium, 
 
 Uranium, 
 
 Iron, 
 
 Tantalium, 
 
 Cerium. 
 
 Zinc, 
 
 
 
 Palladium, 
 
 
 
 Nickel. 
 
 
 
 A lustre is peculiar to the metals, which, there- 
 fore, is called the metallic lustre : another remark- 
 able property is their want of transparency when 
 intbe mass; but, as leaf gold, held between the eye 
 and aluminous body, transmits a green light, and 
 silver awhile light, it seems probable that other 
 
JO 
 
 *j,etalfc, ii' attenuated in the same degree, would 
 also be translucid. 
 
 In weight the metals far exceed the earths; the 
 heaviest of the earths is only about five times 
 heavier than water, but the lightest of the metals 
 is more than six times heavier than water. Beat- 
 en gold is nineteen ^irnes heavier than water ; 
 and beaten platina, &*i heaviest of all, is twenty- 
 three times heavier W^an water. 
 
 The characters of froibility and extensibility in 
 rrretals, is of vast impoHance to man ; for without 
 these characters neithjr could they be freed from 
 the earths and other impurities with which they 
 are naturally found ; nS without these character? 
 could they be wroughjTinto vessels for his use. 
 
 Metals are beliertH^gk to be simple substances : 
 not one of them hasYtiffierto been decomposed. 
 
 The only metals th2t)as yet, have been found 
 IB the pure or rctffuv^state, are platina, gold, 
 silver, quicksilver, coppfer, antimony, arsenic, tel- 
 lurium, bismuth, and i^n. But the greater part 
 >f these are rarely fouflfi quite pure, but mostly 
 have small proportions Bother metals intermixed. 
 
 In order to illustra^rhe very brief view I am 
 about to take of the s^ral metals, I shall offer 
 \o your inspection sftecikiens of some of them as 
 they are naturally ftjmra either in their simple 
 state, (if so found) or as^fiokning those compounds 
 which are denominated metalliferous ores. 
 
 An ore is a compound of two or more metals, 
 bi 1 of a metal in combination with oxygen; (whence 
 
If 
 
 a combination Las obtained the name of a. 
 metallic oxide ;) or a metal combined with an 
 aciW, or with a combustible. Many ores are of so 
 compound a nature as to consist of two or three 
 metals united with oxygen, sulphur, one or more 
 of the earths, and with water. 
 
 I now proceed to invite your attention to the 
 metals individually ; beginning with those which 
 possess the qualities of fusibility, ductility, and 
 malleability, so important to man. 
 
 PLATINA is about twenty-three times heavier 
 than water ; hitherto it has only been found in 
 Peru, Brazil, Spain, and in the island of St. 
 Domingo. In Peru, it is found in little flattened 
 grains, rarely exceeding the size of a pea, accom- 
 panied by gold, and the ores of titanium and 
 iron ; yet it is said that Humboldt presented the 
 King of Prussia with a mass larger than a pigeon's 
 egg. But the grains of crude platina are not 
 pure ; analysis has proved them to consist of 
 platina alloyed by four other metals, osmium, 
 iridium, rhodium, and palladium, which will here- 
 after be noticed. The platina of Brazil is 
 alloyed by gold and silver ; that of Spain was 
 found in a gray silver ore. 
 
 Crude platina is very difficult of fusion. Pure 
 platina, in thin plates, is very ductile and flexible. 
 Of late it has been formed into mirrors for reflect- 
 ing telescopes, spoons, crucibles, and some vessels 
 of considerable dimension for the use of the ch<> 
 
32 
 
 mist in particular processes. So ductile isplatina^, 
 that Dr. Wollaston has lately succeeded in draw- 
 ing it into a wire T?-TT? P art f an mcn in dia- 
 meter. 
 
 GOLD, when pure and beaten, is about nineteen 
 times heavier than water, is very soft, and per- 
 fectly ductile and flexible. So great is the 
 tenacity of gold that a piece one-tenth of an inch 
 in diameter, will hold five hundred pounds with- 
 out breaking ; and it is computed that a single 
 grain of gold will cover the space of fifty-six 
 square inches, when beaten out to its greatest 
 extent. 
 
 Gold is mostly found in the metallic form, 
 whence, by mineralogists, it is said to occur in the 
 native or pure state ; but it is generally alloyed 
 by small portions of other metals, as silver, copper, 
 &ic. It occurs in mineral veins and beds, or dis- 
 seminated in the substance of some of the oldest 
 mountains : it is found in Brazil, Peru, Mexico, 
 Africa, Sumatra, Japan, Hungary, and Transyl- 
 vania. 
 
 Helms says, that when a projecting part of one 
 of the highest mountains in Paraguay fell down, 
 about thirty years ago, pieces of gold, weighing 
 from two to fifty pounds each, were found in it; 
 and that in the Vice-royalty of La Plata alone, 
 there are thirty gold mines. 
 
 Sometimes gold is crystallized in small cubes or 
 regular octohedrons, and as these crystals cannot 
 be broken in, any particular direction, either of 
 
those solids may be said to be tbe primitive crys- 
 tal of gold. In veins it is generally accompanied 
 by quartz, felspar, the ores of tin, silver, lead, 
 and of some other metals. 
 
 A great quantity of gold is obtained in grains 
 and rounded masies in soils, evidently the ruin 
 of rocks which contained it in its natural situation. 
 Jn this state it has been found in Wicklow, in 
 Ireland, and 'in Cornwall, in small quantities. 
 A few years ago, a single specimen of gold, equal 
 in weight to upwards of ten guineas, was found 
 among tin in a stream work in Cornwall. On 
 the coast of California there is a plain of fourteen 
 leagues in extent, about fourteen inches beneath 
 the surface of which, large lumps of gold are irre- 
 gularly interspersed. 
 
 But a still greater quantity of gold has been 
 obtained in the form of a fine sand, from the 
 Peruvian, Mexican, and Brazilian rivers, and from 
 some of the African. In Europe, the Danube, 
 the Rhine, and the Rhone, and the streams of 
 Hungary and Transylvania, afford small quan- 
 tities. 
 
 The uses of gold are well known. Alloyed by 
 copper, it is employed for ornamental purposes, 
 coi'>, and plate. 
 
 In English coin it was alloyed by two parts 
 of copper to twenty-two of gold. The purple- 
 colour used in porcelain painting is obtained from 
 a preparation of gold. 
 
34 
 
 SILVER, when pure, is ten times heavier than 
 water, and is soft, opake, and flexible ; a piece 
 $ne tenth of an inch in diameter will support two 
 hundred and seventy pounds without breaking. 
 
 Silver naturally occurs in the pure or native 
 state ; but is sometimes alloyed by a small pro- 
 portion of gold, sometimes of copper. It is found 
 in fine filaments disseminated through rocks, but 
 chiefly in veins, in primitive and secondary moun- 
 tains, occasionally crystallized in cubes and re- 
 gular octohedrons, and accompanied by calca- 
 reous and other spars, iron pyrites, cobalt, and 
 some other substances. It is found in Peru, 
 Mexico, Saxony, Bohemia, Norway, Hungary, 
 and England. 
 
 The ores of silver are numerous ; for although 
 it mostly occurs in the pure state, it is also found 
 combined with gold, copper, antimony, iron, lead, 
 bismuth, arsenic ; with the earths, silex, and alu- 
 mine, and mineralized by the muriatic, sulphuric 
 or carbonic acids, and by sulphur. 
 
 The most common ore of lead, called the sul- 
 phuret, mostly contains some portion of silver, 
 but not always worth extracting. The lead from 
 the Westmoreland and Cumberland mines, yields 
 an average of seventeen ounces of silver to the 
 ton of lead. The Beeralston mines in Devon- 
 shire, yield about forty-two ounces. The richest 
 perhaps ever known, was that found at Brunghill 
 Moor, in Yorkshire ; which yielded two hundred 
 and thirty ounces to the ton. 
 
35 
 
 According to Helms, the mine of Jauricocha* 
 in Peru, which is about three miles above the 
 sea, contains a prodigious mass of porous brown 
 iron-stone, half a mile long, as much broad,, 
 and about one hundred feet in depth, which is 
 throughout interspersed with pure silver, and a 
 white argillaceous vein very much richer. It is 
 asserted that Jauricocha, and the mines of the dis- 
 trict surrounding it, have yielded forty millions of 
 dollars in a year. 
 
 It is said that, in 1750, a mass of silver was 
 found in a mine near Freyberg, in Saxony, weigh- 
 ing upwards of 140lbs. and another of about the 
 same siz.e, in 1771. In the year 1748, a block of 
 native silver and silver ore was cut out in a rich 
 vein of silver, near Schneeberg ; Duke Albert, of 
 Saxony, descended the mine, and used it as a din- 
 ner table. When this huge block was smelted, it 
 yielded 44,0001bs. of silver. We are told that 
 Annibal received 300 pounds weight of silver, 
 daily, from the mines near Carthagena, in Spain. 
 
 The uses of silver are numerous, and for the 
 most part obvious. In coin, silver is alloyed by 
 one part of copper to fifteen of silver. The yellow 
 colour used in porcelain painting is oxide of silver, 
 
 MERCURY or QUICKSILVER, is thirteen times 
 heavier than water, and is fluid in the natural 
 temperature of the atmosphere. 
 
 It mostly occurs pure (but sometimes'contains 
 a little silver) disseminated in globules, or col- 
 lected in the cavities of its mines, which are most 
 
commonly situated in calcarerous rocks, or indu- 
 rated clay, or argillaceous schislus. 
 
 Quicksilver mines are worked in Camiola, the 
 Duchy of Deux-ponts, Spain, and Peru. The 
 vein of Guancavelica, in South America, in which 
 quicksilver* is found in the state of cinnibar, is 
 80 Spanish ells in extent, and is situated partly in 
 sandstone, partly in limestone. The cinnabar is 
 accompanied by the sulphuret of lead, calcareous 
 spar, barytes, quartz, manganese, arsenic, &c. 
 
 The quicksilver mines of Idria, in Saxony, are 
 said to yield 100 tons annually; and those of 
 Spain a still greater quantity. 
 
 The ores of mercury are not numerous : com- 
 bined with silver, it is called native amalgam, 
 with sulphur and iron, cinnibar. Horn mercury 
 is a natural combination of mercury mineralized 
 by the sulphuric acid, and of mercury mineralized 
 by the muriatic acid. 
 
 The uses of mercury in medicine, in the arts, 
 and in experimental philosophy, are numerous ; 
 but its chief use is in the separation of gold and 
 silver from their ores, by a process called amal- 
 gamation. When amalgamated with tin, and laid 
 on glass, it forms mirrors. 
 
 LEAD, when pure, is more than eleven times 
 heavier than water; a piece one- tenth of an inch 
 in diameter, will hold twenty-nine pounds with- 
 out breaking. 
 
 Lead has nevsr yet been found pure in the 
 aatural state. Its ores are numerous, and occur 
 
37 
 
 in beds or veins in almost every mineral district 
 in the known world, and are, perhaps, next to 
 those of iron, the most common of metalliferous 
 ores. 
 
 Lead is found in combination with other metals, 
 as antimony, iron, and silver ; and the two earths, 
 silex and lirne. It is found mineralized by the 
 carbonic, muriatic, phosphoric, arsenic, molybdiCf 
 and chronic acids, and with oxygen, which cause 
 it to lose every appearance and character of lead ; 
 but many of its ores have not been analysed. 
 
 The most common of the ores of lead, is by far 
 of the greatest importance to man, because, from 
 it are principally derived the immense quantities 
 of lead for his use. It is called galena, or sul- 
 phuret of lead ; by analysis it yields lead, sulphur, 
 oxide of iron, and sometimes lime and silex; most- 
 ly some silver. It occurs in beds or veins in primi- 
 tive or secondary mountains, most abundantly in 
 argillaceous schistus and secondary limestone, ac- 
 companied by blende and calamine, the ores of 
 zinc ; and is sometimes compact, sometimes crys- 
 tallized in the cube or regular octohedron. 
 
 It would scarcely be possible to enumerate all 
 the valuable purposes to which lead is applied 
 in the arts, in medicine, and in the common wants 
 of man. Among its less obvious uses, lead is- 
 employed to glaze pottery, and its oxide enters 
 into the composition ef glass. Four parts of 
 lead and one of antimony form printing types; to 
 which, by some, is added a little copper or brass, 
 E 
 
38 
 
 With lia and bismuth it forms alloys mentioned 
 in the notice of those metals. 
 
 COPPER, in its pure state, is about eight times 
 heavier than water; a wire one-tenth of an inch 
 in diameter will support two hundred and ninety- 
 nine pounds and a half without breaking. 
 
 It is a very malleable and ductile metal, of a 
 pale red colour, with a tinge of yellow. In the 
 natural state it occurs very pure ; and its ores are 
 very numerous. In both states, it is found in 
 almost every mineral district in the world, in 
 beds, or more commonly in veins, in primitive 
 and secondary mountains, accompanied by seve- 
 ral other mineral substances, as the ores of zinc, 
 and occasionally of lead, sometimes of tin; with 
 quartz, and fluate of lime, and calcareous spar in 
 abundance. 
 
 Native or pure copper, is not, however, found 
 either in beds or veins in great quantities ; that 
 of Japan and of Brazil is alloyed by gold. 'A 
 mass of native copper is said to have been found 
 in a valley in Brazil weighing 2666 Portuguese 
 pounds. Wherever found, it is of various shapes, 
 and sometimes crystallized in the cube and regu- 
 lar octohedron. 
 
 Mineralized by a certain proportion of oxygen, 
 it forms a beautiful mineral, called the red oxide 
 of copper, which assumes a great variety of forms, 
 all of which may be traced into the regular octo- 
 hedron ; with an increased proportion of oxygen, 
 it assumes a black hue, and is mostly pulverulent. 
 
Copper is found combined with iron and arse - 
 nic, with lime and silex, and mineralized by the 
 phosphoric, carbonic, arsenic, or muriatic acids, 
 which cause it to lose all metallic character and 
 appearance. 
 
 The most common copper ore of the Cornish 
 mines is of a yellow colour, called yellow copper 
 ore, or copper pyrites ; analysis proves it to con- 
 sist of copper, iron, and a large proportion of 
 sulphur. 
 
 The uses of copper, in all its various states, are 
 almost endless, and only, if at all, inferior to those 
 of iron. Alloyed with certain proportions of zinc 
 it forms brass, pinchbeck, tinsel, and Dutch gold., 
 in imitation of gold leaf. With a small propor- 
 lion of tin, copper forms bronze or bell metal ; 
 but if the proportion of tin amount to one-third, 
 it forms speculum metal, used for reflecting tele* 
 scopes. With zinc and iron, it forms tutenag. 
 In porcelain painting, the green is obtained from 
 copper. 
 
 TIN, in' its pure state, is about seven times 
 heavier than water, but has never been found 
 pure. In the common ore of tin mines, it is 
 always in combination with oxygen, whence it is 
 termed an oxide ; but analysis proves it also to 
 contain small portions of iron and of silex. 
 
 In one vein in Cornwall, an ore has been found 
 called the bell metal ore, (from its resemblance to 
 that metal in colour,) which consists of tin, copper, 
 aud sulphur, together with a small portion of iron, 
 
40 
 
 A variety of the oxide of tin, called wood tut, 
 is found sparingly in two or three places in Corn- 
 wall only. 
 
 Tin is considered to be one of the oldest metals, 
 because it is principally found in those rocks 
 which, from their not containing any animal or 
 vegetable remains, are termed primitive. It occurs 
 disseminated in them, or in beds, but principally 
 nn veins, accompanied by the ores of tungsten, 
 arsetlic, iron, copper, and zinc, and with quartz, 
 mica, fluate of lime, and some other substances. 
 
 The ore of tin is also abundantly found in 
 Cornwall, in rounded portions or grains, in what 
 :ire termed alluvial beds; that is, in depositions 
 which have resulted from the ruin of rocks. 
 
 Tin is by no means one of the most commonly 
 < Utilised metals. It is most abundant in Cornwall; 
 but it is also found in Gallicia, in Spain, in 
 Saxony, in Bohemia, in Malacca and Banca, in 
 Asia, and in Chili, in South America. 
 
 The alloys of tin with other metals, are men- 
 tioned in treating of lead, copper, and quicksil- 
 ver. Another will be noticed under the article 
 bismuth. In a fine leaf, as tin foil, it is used for 
 many purposes ; its salts are used in dying : its 
 economical purposes are well known. 
 
 IRON, when pure, is about seven times heavier 
 than water ; it is one of the most, if not the most, 
 universally diffused substances in nature ; it is 
 found in all soils, and in almost every rock. 
 
41 
 
 Iron has been said to have been found in a 
 mine in Saxony, in the pure or native state, 
 alloyed by small proportions of lead and copper ; 
 but the fact has not been satisfactorily ascertained. 
 But some masses of a substance, which by some 
 is termed nati.e iron, have been found in differ- 
 ent quarters of the globe ; in Bohemia, in Senegal, 
 in South America, and in Siberia ; of the latter 
 we have the best account. It was found by pro- 
 fessor Pallas on the top of a mountain, on which 
 there was a considerable bed of magnetic iron- 
 stone, on the banks of the river Jenisei. It weigh- 
 ed 1680 Russian pounds, and possessed some of 
 the important characters of pure iron, as mallea- 
 bility and flexibility, and was reported by the in- 
 habitants of the country to have fallen from the 
 sky. The mass found in the Vice-royalty of 
 Peru, in South America, was described by Don 
 Rubin de Celis : it weighed about fifteen tons ; it 
 was compact externally, and was marked with 
 impressions as if of hands and feet, but much lar- 
 ger, and of the claws of birds ; internally it pre- 
 sented many cavities : it was nearly imbedded in 
 white clay, and the country round it was quite flat 
 and destitute of water. 
 
 Most of these masses termed native iron, (which 
 from a current belief of their having fallen from 
 the sky, have also obtained the names of meteoric 
 iron) have been subjected to analysis, and in each 
 the iron has been found alloyed with more than 
 one-tenth of the rare metal called nickel ; which 
 E 2 
 
also, it is worthy oi' remark, is found, by analysis, to 
 be a constituent part of all those stones, which, in 
 various parts of the European Continent, in Eng- 
 land, and in America, have been known to fall 
 from the sky, and are therefore termed meteoric 
 stones. 
 
 The ores of iron are numerous, and are found 
 in beds, in veins, and disseminated in rocks. 
 It occurs combined with manganese, carbonate of 
 lime, silex, alumine, sulphur, or oxygen : with 
 copper, the arsenic acid, oxygen and silex, it forms 
 a beautiful mineral crystallized in cubes of a 
 green colour, which are often transparent ; it is 
 called the arseniate of iron. An ore, in which 
 iron is combined with alumine, is used in the 
 making of what are termed red lead pencils. 
 Plumbago, or black lead, is a natural compound of 
 iron, with a large proportion of carbon. 
 
 It would be vain to attempt the enumeration 
 ef the uses to which iron is put by man. Steel is 
 an artificial combination of iron with carbon. 
 The red colour used in porcelain painting is oxide 
 of iron. 
 
 ZING, when pure, is about seven times heavies 
 than water; its tenacity is not great ; a piece one- 
 tenth of an inch in diameter will hold twenty-six 
 pounds without breaking ; and being far less duc- 
 tile than some other metals, its importance is 
 thereby diminished. 
 
 Zinc is never found pure, its ores are only three 
 jn number, but of these some varieties are found* 
 
Zinc, as an oxide, combined with carbonic acid, 
 forms a most abundant ore, called calamine. 
 Zinc, as an o.iide, combined with sile;f, forms 
 electric calamine, so termed from its becoming 
 electric when slightly heated. Zinc, ' combined 
 with iron, sulphur, silex, and water, forms that ore 
 called blende ; a variety of which, on being scratch- 
 ed, emits a phosphoric light. 
 
 The ores of zinc are found in most mineral 
 countries ; most abundantly in the transition or 
 earlier secondary rocks, accompanied by iron 
 pyrites, sulphuret of lead, some of the ores of 
 silver, and by calcareous spar and quartz. 
 
 Zinc is employed by the Chinese for coins : it 
 enters into the composition of many alloys ; (see 
 copper.) It is sometimes used in medicine, and 
 in oil painting. 
 
 PALLADIUM, is about eleven times heavier 
 than water ; it is very malleable, and equal in 
 hardness to bar iron. It has hitherto only been 
 obtained by the chemist from crude plalina (see 
 Platina,) which it greatly resembles in colour : it 
 has never been applied to any use. 
 
 NICKEL is about nine times heavier than water, 
 and is of a yellowish white ; it is not perfectly 
 malleable. 
 
 Nickel has never been found in the pure state': 
 its ores are few ; they have been found in mineral 
 veins and beds in France, Spain, Bohemia, Sibe- 
 ria, and in England sparingly ; they are generally 
 accompanied by the ores of silver and cobalt, by 
 
44 
 
 calcareous spar and quartz, and some other sub- 
 stances. 
 
 It is remarkable that nickel, which is one of 
 the least abundant metals, has been found, by 
 analysis, to enter into the composition of those 
 stony substances which, in various parts of Europe 
 and America, have fallen from the atmosphere ; 
 whence they are termed meteoric stones. 
 
 The uses of nickel are not numerous ; it is 
 chiefly employed in alloys with other metals. 
 
 We have now taken a slight view of the eleven 
 metals, which have been termed perfect, on ac- 
 count of their possessing the valuable properties 
 of fusibility, ductility and malleability. I now pro- 
 ceed to those which, not possessing the two latter 
 properties, have been by some termed the brittle, 
 or semi-metals. 
 
 ARSENIC is nearly eight times heavier than 
 ;vater, and is of a bluish white. 
 
 It is found nearly pure, being alloyed only by 
 small portions of iron and sometimes of gold or 
 silver, only in primitive mountains, in veins, ac- 
 companied by some ores of silver, cobalt, and 
 lead ; by calcareous spar, fluate of lime, and 
 quartz, and some other substances. It is princi- 
 pally found in certain districts of Germany. 
 
 Arsenic, combined* principally with iron, forms 
 a mineral called arsenical pyrites, or mispickel ; 
 In some of the varieties of which, silver is found, 
 
45 
 
 This also principally occurs in veins in primitive 
 mountains. 
 
 Arsenic is found combined with twenty-five 
 parts of sulphur, forming an ore of a red or 
 orange colour, called realgar, and with forty- 
 three parts of sulphur, it forms an ore of a bright 
 lernon yellow colour, called orpiment. Realgar 
 is said to occur principally in primitive moun- 
 tains ; orpiment principally in flcetz or secondary 
 mountains. 
 
 Arsenic is one of the least useful metals, and 
 though a poison, is used in medioine ; it is also 
 used in the making of glass : orpiment is employ- 
 ed as a paint. 
 
 ANTIMONY is a compact, brittle, whitish metal, 
 about six times heavier than water. It is found 
 nearly pure, being alloyed only with very small 
 portions of silver and iron. Native or pure anti- 
 mony is found in veins in the mountains of Dau- 
 phine, in the Hartz, ic. and in Sweden, dissemi- 
 nated in calcareous spar. 
 
 The ores of antimony are only five in number; 
 all of which have not been analysed. In some of 
 them, it is found combined with oxide of iron, co- 
 bait, arsenic, silex, sulphur, oxygen. They are 
 found principally in veins in primitive, and in 
 transition, or the older secondary, mountains in 
 Sweden, Saxony, France, Bohemia, England, 
 and other mineral countries. 
 
 Antimony forms alloys with other metals, and 
 is used in the arts. It enters largely into the com- 
 
46 
 
 position of printing types ; it is also used in medi- 
 cine. 
 
 BISMUTH is nearly 10 times heavier than water; 
 it is of a reddish- white colour, and very brittle. 
 
 It is found in the pure state somewhat alloyed 
 by arsenic. 
 
 The ores of bismuth are only two in number ; 
 in that called sulphuret of bismuth* it is com- 
 bined with sulphur; in the other, called bismuth 
 ochre, it is mineralized by oxygen, and combined 
 with small portions of oxide of iron and carbonic 
 acid. a 
 
 Native bismuth is rare, as well as its ores ; 
 these are found in veins mostly in primitive moun- 
 tains, accompanied by the ores of cobalt, of iron., 
 of zinc, and sometimes of silver, and by quartz, 
 calcareous spar, and barytes ; in Bohemia, Tran- 
 sylvania, France, and Sweden. The sulphuret 
 of bismuth has occurred in Cornwall. 
 
 Bismuth is very little used, but it enters into 
 the composition of some of the soft solders, and 
 of sympathetic ink. It forms alloys with other 
 metals. Tin and bismuth are two of the most 
 fusible metals. The fusible-metal of Sir Isaac 
 Newton, is composed of 8 parts of bismuth, 5 of 
 lead, and 3 of tin ; when this is thrown into water, 
 and heat applied, it melts a little before the water 
 has reached the boiling point. 
 
 COBALT, when pure, is about 8 times heavier 
 than water : it is of a gray colour, with a red tinge* 
 and has the magnetic properties of iron, 
 
47 
 
 It is not found pure. Its ores are not numerous. 
 In one of them from Tunaberg, in Sweden, it is 
 combined with arsenic and sulphur, and some- 
 what in form and colour, resembles iron pyrites. 
 In Cornwall, it is found combined with arsenic 
 and iron. Its other ores have not been analyzed, 
 but cobalt seems always to be combined with 
 arsenic. 
 
 The ores of cobalt occur in veins both in primi- 
 tive and in secondary mountains : mostly accom- 
 panied by some of the numerous ores of copper, 
 sometimes by native bismuth, native silver, native 
 arsenic, and the ores of silver. 
 
 Cobalt is very little used except in the arts. It 
 is brought to this country reduced to the state of 
 an oxide, of an intense blue colour, called zaffre, 
 which, when melted with 3 parts of sand and 1 of 
 potash, forms a blue glass, and when pounded very 
 fine, is called smalts, and is then employed to 
 give a blue tint to writing papers, and in the pre- 
 paration of cloths, laces, linens, muslins, &ic. ; for 
 colouring glass, and for painting blues on porce- 
 lain. So intense is the blue of zaffre, that one 
 grain will give a full blue to 240 grains of glass. 
 
 MANGANESE is of an iron gray colour, very 
 brittle, and seven times as heavy as water. 
 
 It is never found pure. Its ores are not nume- 
 rous. It is found combined with the oxide of iron, 
 with sulphur, the sulphuric or carbonic acid, bary- 
 tes, or most abundantly with oxygen, as an oxide 
 of a brown colour or black. 
 
46 
 
 The ores of manganese are found in various 
 parts of the continent of Europe, and in the mine- 
 ral districts of Britain. 
 
 From the black oxide of manganese, all the 
 oxygen gas used by the chemist is obtained, and 
 all the oxygen entering into the composition of 
 the oxymuriatic acid consumed in the bleache- 
 ries of Britain, France, and Germany. The vio- 
 let colour employ ed in porcelain painting is obtain- 
 ed from manganese. In glass-making, it is employ- 
 ed in the finer kinds of glass, both as a colouring 
 material and a destroyer of colour : this applica- 
 tion of it is ancient ; it is ment ; oned by Pliny. 
 
 TELLURIUM, when pure, is about the colour 
 uf tin. It is brittle, nearly as fusible as lead, and 
 is six times heavier than water. 
 
 It is an extremely rare metal, and is found in the 
 iiative state, but always alloyed by other metals, 
 principally in veins traversing SCCOL < iy rocks in 
 Transylvania. A variety called the gray gold ore 
 of Nagyag, has been found, by analysis, to consist 
 of tellurium, had, gold, silver, copper, aud sulphur, 
 
 It has never been made any use of. 
 
 TITANIUM is so difficult of fusion, that the 
 attempts to reduce it to a pure metallic state, 
 have scarcely succeeded.* It is of a copper red 
 colour. 
 
 Two of its ores are said to be nearly pure o rides. 
 In others, is found in combination with oaide of 
 iron, manganese, and site.r. They occur sparingly 
 
a 
 
 in Hungary, Transylvania, France, Britain, and 
 North and South America. 
 
 The hair-like appearances sometimes to be ob- 
 served in crystals of quartz, are mostly crystals 
 of titanium. An ore of titanium is found in a 
 stream in Cornwall in black grains ; another is 
 found in Transylvania resembling yellow sand. 
 
 The only use'to which titanium has ever been 
 put, was in the porcelain manufactory at Sevres, 
 where it was employed to produce the rich browns 
 in painting it. The want of uniformity in colour 
 occasioned its disuse. 
 
 TANTALIUM is a metal, having but a slight 
 external metallic lustre ; it is dull, and almost 
 black internally. 
 
 It is extremely rare ; having hitherto only been 
 found in Finland and Sweden. In Finland, it 
 occurs combined with oxide of iron and of manga- 
 nese, forming a mineral called tantalite, imbedded 
 in quartz, in veins that traverse a red granular 
 felspar. In Sweden, it is found in a mineral 
 called yitrotantalite, because analysis has proved 
 it to be principally composed of the rare earth 
 yttrictj and the rare metal tantalium. This mine- 
 ral occurred in a granite rock. 
 
 MOLYBDENA, when pure, is of a grayish white, 
 and in the form of brittle infusible grains. 
 
 It is very rare, and has never been found pure. 
 Combined with sulphur, it is found in veins in 
 primitive mountains, in Norway, Sweden, Saxony, 
 F 
 
50 
 
 and Switzerland, accompanied by tin, wolfram, 
 quartz, and mica. 
 
 The molybdic acid has been found combined 
 with lead, forming a mineral called molybdate *>/ 
 lead, in Carinthia, Saxony, Hungary, and Austria, 
 accompanied by calcareous spar, sulphuret of 
 lead, the ores of zinc, and fluor spar. 
 
 Molybdena has never been applied to any use. 
 
 TUNGSTEN is a hard, brittle, granular metal, 
 of a light steel-gray colour, and brilliant metallic 
 lustre. 
 
 It is not found pure. 
 
 The oxide of tungsten, combined with lime 
 and silex, has been sparingly found in Sweden, 
 Bohemia, and Cornwall. The compound is call- 
 ed tungstate of lime. 
 
 Combined with oxide cf iron, manganese, and 
 silex, it forms a mineral called tungstate of iron, 
 or ivclfram, which occurs in most districts in which 
 tin is found. 
 
 The only use to which tungsten has hitherto 
 been applied is in the arts, as forming, in com- 
 bination with other substances, those red paints 
 known by the name of lake. 
 
 CHROME, is a metal of a grayish-white colour, 
 and extremely brittle ; it is remarkable that it 
 has never been found in the metallic form, but 
 only in the acid state, or in that of an oxide. 
 
 The chromic acid, in combination with lead, 
 forming a compound mineral called chromate of 
 had, has been found principally, in veins in gneiss 
 
51 
 
 and mica-slate, in a gold mine in the Uralian. 
 mountains, in Siberia : it is said also to have oc- 
 curred at Annaberg, in Austria, arid at Trapettes, 
 in Savoy. It is extremely rare. 
 
 The occide of chrome, in combination with oxide 
 of iron , alumine and silw, forms a mineral called 
 chr ornate, of iron, which is found very plentifully 
 in France, and ki some places in Siberia. 
 
 The chromate of lead, on account of its beauti- 
 ful red colour, has been employed in Russia as a 
 paint. Chrome, as obtained in tke metallic state 
 by the chemist from either of the two foregoing 
 compounds, has not been applied to any important 
 use : it tinges glass of a green colour. It has 
 been ascertained that the emerald owes its beauti- 
 ful green colour to oxide of chrome : it seems, 
 therefore, probable, that chrome may hereafter be 
 employed as a paint. 
 
 OSMIUM, 
 
 IHIDIUM, and 
 
 RHODIUM, are three brittle metals which, to- 
 gether with PALLADIUM, already noticed as a 
 malleable metal, have, by analysis, been found in 
 combination with PLATINA in the crude state, 
 (see Platina.) Not one of these four metals has 
 hitherto been applied to any use. 
 
 URANIUM, is a brittle, granular, hard metal, 
 of extremely difficult fusibility. 
 
 It is remarkable that this metal has never been 
 found in any state having a metallic appe.arance ; 
 consequently, never in the pure state. Its ores 
 
52 
 
 are only two ; and very rare. They have been 
 found in Saxony, Bohemia, Norway, France, and 
 England ; in the latter only in copper veins. 
 
 Uranium is found only in combination with 
 oxygen, forming an oxide ; or with oxygen and 
 oxide of iron, when it is called uran-ochre. 
 
 The oxide of uranium is a beautiful mineral, 
 mostly in small thin plates of a fine green colour, 
 and transparent: in combination with oxygen and 
 oxide of iron, uranium forms a mineral similar in 
 appearance to pitch ; or sometimes resembling 
 iron-rust. 
 
 No use has hitherto been made of uranium. 
 
 CERIUM has hitherto only been obtained by 
 some chemists from a mineral substance from 
 Sweden, called the cerite, in the form of a white, 
 yellowish, or reddish brown powder : yet, al- 
 though cerium has never been obtained in the 
 metallic form, it is considered from its properties 
 to be a metal. 
 
 It has not been applied to any use. 
 
 We now proceed to the consideration of those 
 mineral bodies which, from their peculiar proper- 
 ties, are termed COMBUSTIBLES. These form, in 
 the mineral kingdom, a class of substances by no 
 means agreeing amongst themselves in internal or 
 external characters, and differing essentially from 
 the earths, the alkalies, or the metals. Combus- 
 tibles include both the hardest and the softest of 
 mineral substances. 
 
Most of the metals, whose properties are altered 
 by combustion, acquire an increase of weight 
 thereby; whereas combustible substances are 
 sensibly diminished in weight by the same process. 
 The product of some of them is liquid, of others ? 
 solid ; if solid, it is insoluble in water. 
 
 The mineral bases of combustible substances 
 may be said to be only two, viz. CAIIBON and 
 SULPHUR. 
 
 Combustible substances may be comprised in 
 the following list : 
 
 Sulphur Coal 
 
 Diamond Blind or Kilkenny Coal, 
 
 Mineral Carbon or Anthracite 
 
 Plumbago, or Graphite Jet 
 
 Mineral Oil [Pitch Amber 
 
 Bitumen, or Mineral Mcllite, or Honey Stone. 
 
 SULPHUR, is a soft, brittle substance, of a 
 pale yellowish colour. It is found either nearly 
 pure, or in combination with certain metallic 
 ores, in great abundance. It is also found both 
 in the vegetable and animal kingdoms. 
 
 The DIAMOND, which is the hardest substance 
 in nature, was heretofore considered as an earthy 
 or stony substance ; but it is proved beyond a 
 doubt not to be an earthy substance. When ex- 
 posed to a current of air, and heated to the tem- 
 perature of melting copper, it is found to be gra- 
 dually, but comjpfeite/^ combi&lible* By this pro- 
 F2 
 
54 
 
 cess, it may be wholly converted into carbonic 
 acid, and therefore consists of pur& carbon. 
 
 Diamonds are either colourless, or of a yellow- 
 ish, bluish, yellowish green, clove brown, black 
 brown, prussian blue, or rose red colour : they 
 are naturally found in detached regular crystals ; 
 their primitive form is the regular oetohedron. 
 In India, diamonds are found in an indurated 
 ochrey gravel. The diamond mines extend through 
 a long tract of country, from Bengal to Cape 
 Comorin : the chief of them are now between 
 Golconda and Masulipatarn. Diamonds are also 
 procured from the isle of Borneo and from Brazil, 
 where they are found in beds of ferruginous sand. 
 
 The principal use of the diamond is in orna- 
 mental jewellery ; it is also employed by glaziers 
 to cut glass, and by lapidaries to engrave the 
 harder gems. 
 
 MINERAL CARBON, or CHARCOAL, is grayish 
 black. It occurs in plates or irregular pieces, in 
 various sorts of common coal. It has a glimmer- 
 ing, silky lustre, and a fibrous appearance, disco- 
 vering a wood-like texture. It is somewhat hea- 
 vier than common charcoal, and is easily reduced 
 to ashes before the blowpipe, without either flame 
 or smoke. 
 
 PLUMBAGO, or GRAPHITE, is found in Eng- 
 land, Scotland, France, Spain, Germany, and 
 some other countries. Plumbago is of a dark 
 iron black, passing into steel gray ; it Las a glis- 
 tening metallic lustre. 
 
55 
 
 The principal use of plumbago is in the making 
 of what are called Hack-lead pencils ; for which 
 purpose none has yet been discovered equal to 
 that from Borrodale, in Cumberland. 
 
 Whence this mineral obtained the name of 
 black-lead it is difficult to say, unless it was from 
 the lead- coloured streak which it gives upon pa- 
 per. It Iras been ascertained that lead does not 
 enter into its composition, but that the purest 
 plumbago consists of about 90 parts of carbon and 
 1 of iron. 
 
 MINERAL OIL. Under this term are compre- 
 hended two substances, naptha and petroleum ; 
 both of which are liquid, highly inflammable, and 
 lighter than water. 
 
 Naplha is nearly colourless and transparent ; 
 it gives out much smoke and a penetrating odour 
 in burning. The most copious springs of naptha 
 are on the coast of the Caspian sea. It is employed 
 externally for strains and bruises. The Persians 
 and Russians are said to take it as a cordial. 
 
 Petroleum, at the usual temperature, is rather 
 thicker than common tar, and has a strong, disa- 
 greeable odour. It is principally found in coal 
 countries, as in Colebrookdale. It is found in 
 France, Italy, Switzerland, Germany, Hungary, 
 and Sweden. 
 
 It is most plentifully found in Asia : round the 
 town of Rainanghong,.in the Birman empire, 
 there are 520 wells in full activity, into which 
 petroleum flrjws from over coal. No water ever 
 
penetrates into lliese wells. The quantity of 
 petroleum annually produced by them amounts 
 to more than 400,000 hogsheads. To the inha- 
 bitants, its uses are important; it serves instead 
 of oil for lamps, and, mixed with earth or ashes, 
 for fuel. 
 
 BITUMEN, or MINERAL PITCH, is either elastic 
 or compact. 
 
 Elastic bitumen, is of various shades of brown. 
 It has a slightly bituminous odour, and is about 
 the weight of water. It burns readily with a large 
 flame and much smoke, but melts by a gentle heat, 
 and is thereby converted into a substance re- 
 sembling petroleum. 
 
 Hitherto it has only been found in the Odin 
 mine, near Castleton. in Derbyshire, in a secon- 
 dary limestone. 
 
 Compact bitumen is of a brownish-black colour ; 
 one variety may be impressed by the nail, and is 
 called maltha ; another is very brittle, and is call- 
 ed asphalt. 
 
 They consist of carbon, earth, and bitumen. 
 
 The softer variety has not been put to any 
 use ; but the harder is used in varnishes, and is 
 an essential part of those used by engravers. It 
 is found on the shores of the Dead Sea, in the 
 West Indies, and rnany^other places. x 
 
 COAL. The bituminous substance called 
 coal, though ranked among minerals because its 
 basis is pure carbon, is now, by many, b.elieved to 
 be of vegetable origin; because the substance 
 
57 
 
 which lies upon the coal, is always filled with ve- 
 getable remains ; as well as because a woodlike 
 appearance may be traced through every species 
 of coal, even the most compact. 
 
 On the subject of coal deposites, particularly 
 our own, it is my intention to treat more at large. 
 
 Coal may be divided into three species : brown 
 eoal, black coa^ and canncl coal. 
 
 Brown coal is in. perfectly bituminous; in* all 
 its varieties it is fibrous, and in some of them its 
 vegetable origin is so complete, as that the re- 
 mains of the trunks and branches of trees are 
 visible, and almost perfect. Brown coal burns 
 with a weak flame and disagreeable odour. It is 
 found in horizontal strata. In England it occurs 
 at Bovey, near Exeter, and is called Bovey coal. 
 It is also found in other countries. 
 
 Black coal, which is used for economical pur- 
 poses, includes several varieties. It may, how- 
 ever, generally be said to be of a black colour, 
 having an iridescent tarnish, and a high resinous 
 lustre. It is composed of about 60 parts of car- 
 bon, and 4 of bitumen. It always occurs in near- 
 ly horizontal strata, which are abundant in Dur- 
 ham; Lancashire, Yorkshire, and in some other 
 parts of England, and in several parts of Europe. 
 
 Cannel coal is chiefly found at Wigan, in Lan- 
 cashire, but is more or less abundant in most 
 collieries. It is very brittle, of a shining lustre, 
 it crackles and flies while burning, flames much, 
 
58 
 
 and burns quickly, leaving only 3 or 4 parts in 
 the 100 of ashes. 
 
 BLIND, or KILKENNY COAL, or ANTHRACITE, 
 is of a dark iron black, and has a bright, metallic 
 lustre. It burns without smoke, and emits no 
 sulphureous or bituminous odour. It consists of 
 pure carbon, with some silex, and a small portion 
 of oxide of iron. 
 
 JET, or PITCH COAL, is generally of a velvet 
 black ; it occurs in mass, and sometimes in the 
 shapes of branches, with a regular woody structure. 
 It has a brilliant, resinous lustre. It is used as 
 fuel, but the finer and harder pieces are worked 
 into trinkets, under the name of jet. It is found 
 in the Prussian amber mines in detached frag- 
 ments, and is there called black amber. 
 
 AMBER is a mineral of a yellow, or reddish- 
 brown, or of a greenish, or yellowish white colour. 
 It is found in nodules, or rounded masses, from 
 the size of coarse sand to that of a man's head; 
 
 Ambreis found on the shores of the Baltic, of 
 Sicily, and of the Adriatic Sea, and occasionally 
 in the gravel beds near London. Near the sea- 
 coast, in Prussia, there are regular mines of amber : 
 under a stratum of sand and clay, about 20 feet 
 thick, succeeds, a stratum of trees, 40 or 50 feet 
 thick, half decomposed, impregnated with pyrites 
 and bitumen, and of a blackish-brown colour. 
 Parts of these trees are impregnated with amber, 
 which sometimes is found in stalactites depending 
 from them. Under the stratum of trees was 
 
59 
 
 found pyrites, sulphate of iron, and coarse sand, 
 in. which were rounded masses of amber. The 
 mine is worked to the depth of 100 feet, and from 
 the circumstances in which the amber is found, 
 it seems plain that it originates from vegetable 
 juices. Amber sometimes incloses insects, be- 
 lieve'd to be of the ant species. The strong elec- 
 tric powers of amber are generally known. 
 
 Amber yields, by distillation, an acid called the 
 succinic acid, and leaves, as the residue, an ex- 
 tremely black, shining coal, which is employed 
 as the basis of the finest black varnishes. When 
 exposed to flame in the open air, amber takes 
 fire, and burns with a yellowish flame, giving out 
 a dense, pungent, aromatic smoke, and leaving a 
 light, shining, black coal. 
 
 The MELLTTE or HONEYSTONE is a rare mine- 
 ral, having hitherto only been found in Thuringia, 
 in the district of Saal, and in Switzerland. It 
 occurs on bituminous wood, and earthy coal, and 
 is generally accompanied by sulphur. 
 
 The honeystone is softer than amber, is trans- 
 parent, brittle, and electric, and is found crys- 
 tallized in the octohedron. 
 
 When burnt in the open air, neither smoke nor 
 flame are observable, and it eventually acquires 
 the colour and consistence of chalk. By analysis, 
 it gives a peculiar acid, called the tn-iiitic add, 
 in combination with alumine, together with small 
 portions of iron and silex. 
 
We have now concluded the subject. What 
 has been said was intended only to convey the 
 elements of Mineralogy. There exists a vast 
 multitude of mineral compounds, which it was not 
 possible to offer to your notice in so short a space 
 of time, and which involve many inquiries and re- 
 searches belonging more properly perhaps to the 
 mineralogist in his closet. 
 
 It may be observed, that, although we should 
 now have been ignorant of the existence of some 
 of the earths and metals, but for the researches of 
 the chemist, yet, the properties and uses of by 
 far the greater number of those which are most 
 useful to man, were known, and employed in his 
 service, long before chemistry was pursued as a 
 science. Perhaps not one half of the earths, 
 rnetals, and combustibles, have, in any important 
 degree, been hitherto turned to advantage. 
 
LECTURE III. 
 
 Oi'the objects of Geological inquiry Hypotheses Geological populous 
 Of the low and level parts of the Earth Of the chalk banns of 
 Paris, of London, and of the Isle of Wight. 
 
 IT was said on a former evening that the object 
 of mineralogy is the study of mineral bodies in 
 particular, whether simple or compound : that 
 geology embraces the study of the globe in gene- 
 ral, and of the various relations that the different 
 masses of which it is constituted, bear to each 
 other. Mineralogy may be, therefore, said to fur- 
 nish, as it were, the alphabet to geology. 
 
 The globe we inhabit is about 8000 miles in 
 diameter, 25,000 in circumference. Its surface 
 has two grand divisions, land and water: one- 
 third, or thereabouts, being occupied by land, and 
 two-thirds by water. 
 
 So little was known by the ancients respecting 
 the earth, (of its real form nnd unceasing revo- 
 lutions they were absolutely ignorant.) that it 
 was by them considered to Le the cei.tre <> the 
 universe; of which, a more correct philosophy 
 has proved it to be only t; subsidiary portion. It 
 is not, therefore, to be WOLU* red at, tint in the 
 pursuit of our piesc-nt object, we derive little or 
 no benefit from the writings of ancient profane 
 G 
 
62 
 
 authors. In the time of Herodotus, the Greek 
 historian, it may, however, be inferred that there 
 existed some philosophers who imagined that the 
 earth was round, and that it was encompassed by 
 the sea, since the historian takes the opportunity 
 of sneering at the opinion. 
 
 Geology, or the study of the earth, may be said 
 to be altogether modern, as a science. Until 
 towards the end of the last century, it w 7 as little 
 understood ; perhaps, because those sciences on 
 which it greatly depends, chemistry and mine- 
 ralogy, had not made any large advances towards 
 their present state. It is no marvel, therefore, 
 that in default of a knowledge of the sciences, and 
 of that research by which alone we can become 
 acquainted with the constituent masses of the 
 globe, the activity of the human mind should 
 attempt to account for the creation and present 
 state of the earth by uninstructed efforts of the 
 imagination. It may be amusing to give a short 
 account of a few of these, broached by men calling 
 themselves philosophers. 
 
 In these hypotheses, two events only, the cre- 
 ation and the deluge, seem to have entered into 
 the calculations of the inventors ; as comprehend- 
 ing all the changes to which the globe has been 
 subjected : that is to say, each arbitrarily ascribed 
 toitacertain primitive state, which each supposed, 
 to be altered and modified by the effects of the 
 deluge. 
 
 In the opinion of Burnct t tb<? whole earth n! 
 
63 
 
 first consisted of an uniform light crust, which 
 covered the abyss of the sea ; and which, being 
 broken for the production of the deluge, formed 
 the mountains by its fragments. 
 
 According to Woodward, the deluge was occa- 
 sioned by a momentary suspension of cohesion 
 among the particles of mineral bodies; the whole 
 mass of the globe was dissolved, and the soft paste 
 became penetrated by shells. 
 
 Whiston fancied that the earth was created from 
 the atmosphere of one comet, and deluged by the 
 tail of another. 
 
 The great Leibnitz, as well as Descartes, 
 amused his imagination by conceiving the world 
 to be an extinguished sun or a vitrified globe ; 
 upon which the vapours, condensing in proportion 
 as it cooled, formed seas, and afterwards deposited 
 calcareous strata. 
 
 Dcmaillet conceived the glcrbe to have been 
 covered with water for many thousand years; 
 that it gradually retired ; that all the terrestrial 
 animals were originally inhabitants of the sea ; 
 that man himself began his career as a fish. 
 
 Bvffon imagined, that the mass of our earth, 
 together with those of the other planets, were 
 struck off the sun, in a liquified state, by a comet, 
 at the same instant. 
 
 Some modern philosophers have supposed, 
 every thing to have been originally fluid ; that 
 this universal fluid gave existence to animals of 
 the simplest kind; that in- process of time?hf 
 
64 
 
 races of these animals became complicated, and 
 dying, supplied calcareous earth or lime ; that 
 aluminous earth or clay, was supplied by the de- 
 cay ef vegetables. That these two earths were 
 re-dissolved by a final analysis into silex ; hence 
 that the more ancient mountains are silitious. 
 Thus the solid parts of our globe, according to 
 these visionaries, owe their existence to animal 
 or vegetable life ; and without it, would have 
 continued entirely liquid. 
 
 Kepler, one of the greatest of astronomers, 
 considered the globe to be possessed of living 
 faculties and a circulating vital fluid; that all the 
 particles of it are alive, and possess instinct 
 and volition, whence their attraction and repul- 
 sion : that the organs through which the huge 
 animal breathes are the mountains; that mineral 
 veins are abscesses, and metals the products of 
 rottenness and disease. 
 
 These systems, and even many more than these, 
 have had their admirers, and have successively 
 junk into disrepute and neglect in proportion to 
 the advance of chemical and physical science. It is 
 the apology, if indeed it be not rather the shame 
 of their inventors, that they knew nothing of mi- 
 neralogy, or of the structure of the earth. Two or 
 three theories, of a date much later than the fore- 
 going of the end of the last and beginning of the 
 present century, are worth notice. Marschall sup- 
 poses the fragments of which the surface of the 
 earth is composed to have fallen from heaven. 
 
65 
 
 Bertrand has supposed that the carlh is hollow, 
 and contains within it a load-stone, which is 
 dragged from one pole to the other by the attrac- 
 tion of comets ; so as, by changing its centre of 
 gravity, to drown alternately the two hemispheres. 
 Jameson, now a professor of natural history in 
 one of our own universities, has lately published 
 this amusing query: 'As the true figure of the 
 earth is still unascertained, may we not conjecture, 
 from what is already known, that it is a polyedron 
 (a figure of many sides,) and that the strata, under 
 determinate angles, form the sides and cleavage 
 of this great crystal ?' 
 
 If philosophers, and even naturalists, will still 
 condescend to amuse the world with conceits like 
 the foregoing, it is no wonder that the present pe- 
 riod, with respect to the theory of the earth, should 
 have been said to bear some resemblance to that 
 in which some philosophers thought that the 
 heavens were formed of polished stone, and that 
 the moon was no larger than Peloponnesus. 
 Almost equally absurd, they merit equal notice, 
 as examples of extravagant theory ; but they 
 convey to us at the same time this instructive 
 lesson, that it is only by the patient investigation 
 of facts and of natural phenomena, that we can 
 hope to approach the truth, in the sublime study 
 of the history of the planet we inhabit. 
 
 Within the last few years mineralogy has made 
 
 advances so rapid, as well as other investigations 
 
 G2 
 
66 
 
 connected with the history of the earth, that 
 geology is thereby greatly raised in rank among 
 the sciences. A review of modern researches and 
 discoveries will strikingly evince the folly of any 
 attempt to account, by a turn of the pen, for the 
 creation of the globe, or for the revolutions to 
 which it has been subjected : these researches 
 amongst the phenomena of the earth, will also 
 assure us, that, in whatever manner the mighty 
 display of Omnipotence in its creation was effected, 
 it has since suffered great changes on its surface. 
 
 The elementary substances which have been 
 developed by modern chemistry, as entering in a 
 greater or lefser degree into the composition of 
 mineral bodies, consist of nine earths, twenty -seven 
 metals, two fixed alkalies, and the two bases of 
 combustible substances, carbon and sulphur. 
 
 It is probable that chemistry will yet make 
 great alterations in the catalogue of elementary 
 substances, either by addition or diminution ; 
 most probable by the latter. We shall, however," 
 assume these, according to the present state of our 
 knowledge, to be the elements ofnhich the various 
 constituent masses of the crust of our globe are 
 compounded; but, whether the globe is to its 
 very centre a mass of these compounds, we 
 know not : and since there seems no probability 
 of our arriving at any certainty on this head, let 
 us forbear to conjecture. It is the business of the 
 geologist to investigate natural facts and phenom- 
 ena; and let us be assured that when these fail 
 
67 
 
 to accomplish any desirable purpose, we shall add 
 nothing to our knowledge by soaring into the re- 
 gions of fancy. On a former evening it was said, 
 that as the miner rarely descends below T^^th, 
 part of the earth's diameter, so, if we suppose 
 the earth in shape to resemble an orange, it may 
 be said that we know nothing but of the outer 
 rind. 
 
 Geology, therefore, in the present true sense of 
 the term, embraces little more than an inquiry 
 into the history and present state of the surface or 
 crust of the globe. Disclaiming all theory, it is 
 my purpose to adhere to the legitimate objects of 
 science, as they have been just described, without 
 exerting one pretension beyond them. 
 
 Much has been writt$*i on the subject of the 
 creation ; a subject so far beyond our limit, that 
 upon it I shall be silent ; nor shall I attempt to 
 follow Kirwan through a laborious undertaking 
 to reconcile our partial knowledge of the pheno- 
 mena of nature, and of the constituent masses of 
 the globe, with the Mosaic account of the creation. 
 If ever it should be permitted that man shall com- 
 prehend the great plan by which the Creator re- 
 duced to order the materials of which the globe is 
 composed, with the same certainty as he has at- 
 tained a knowledge of the .mechanism of the uni- 
 verse, some more certain data and discoveries 
 will be allowed to him. than as yet have fallen to 
 his lot. Geology is yet in its infancy : shall we 
 not, therefore, do wisely in concluding that we are 
 
68 
 
 not in the possession of materials sufficient for 
 the investigation ? We have no reason to disbe- 
 lieve that this important branch of geological in- 
 quiry will hereafter be better understood. Con- 
 sidering the present state of our knowledge, we 
 shall be best and most reasonably employed in the 
 investigation of the present state of the earth, and 
 of the changes to which its surface has been sub- 
 jected ; taking as our text, the incontrovertible 
 truth that, ' In the beginning God created the 
 heaven and the earth.' 
 
 Some of the most acute geologist of the present 
 day, have not yet agreed, whether the agent em- 
 ployed in the magnificent work of reducing to 
 order the heterogeneous mass of elementary sub- 
 stances, was fire or water. There exist, at this 
 moment, two distinct parties, distinguished accord- 
 ing to the notion they embrace, by the appellations 
 of Volcanists and Neptunists. Each loudly as- 
 serts tbe preference of its own theory; each per- 
 haps in the possession of chemical facts, or of 
 natural phenomena, establishing, in its separate 
 opinion, its own claim to preference, that have 
 not been controverted by the other. Distinct, 
 however, from these two parties, there are many 
 who wisely think that we are yet too igno- 
 rant to be able, with propriety, to establish any 
 theory at all. These are collecting evidence 
 in regard to its actual state from every quarter 
 flfthe globe, which, if faithfully recorded; may 
 
69 
 
 hereafter enable mankind more nearly to approach 
 the truth than at present it is possible. 
 
 To the results of these inquiries, in so far as 
 they have proceeded, it is my present object to 
 invite your attention. They will comprehend 
 much on the consequences of the catastrophes 
 that have befallen the surface of the earth by the 
 agency of wate*r ; of which we have abundant and 
 incontrovertible evidence : inquiries into the na- 
 ture and component masses of mountains, and of 
 their relative heights ; the internal structure of 
 the earth; mineral veins; the deposites of salt 
 and of coal ; and of volcanoes. 
 
 These are inquiries well meriting our attention ; 
 they will exhibit to us the investigations of men, 
 who, being philosophers in the true sense of 
 the word, have sought and still continue to seek 
 among the instructive records of revolving ages, 
 amid the ruin occasioned by time and circum- 
 stance, the history of the globe we inhabit. 
 
 He who resides in a country which exhibits 
 an almost perpetual verdure, uninterrupted by 
 barren rocks, or desolate regions, and has never 
 visited any other, will scarcely be led to suspect 
 that the surface of the globe has been much con- 
 vulsed by successive revolutions and various ca- 
 tastrophes. If, however, he descend to any con- 
 siderable distance beneath its surface, or ascends 
 the hills that border the plain, he will be likely to 
 receive a new train of ideas; his mind will become 
 
70 
 
 expanded in proportion to the expansion of his 
 view. But if he ascend the elevated chains o-f 
 mountains, or follow the beds of descending tor- 
 rents, which lay open their interior structure, 
 he will become prepared to believe, to their full 
 extent, that various catastrophes have befallen the 
 globe since its creation. 
 
 We reside in a country just now alluded to ; a 
 country of perpetual verdure, uninterrupted by a 
 single rock, or one desolate place. The eleva- 
 tions that surround us scarcely merit the name 
 of hills ; and being all alike verdant, they admit 
 not of investigation, beyond what is attained in 
 the sinking of wells. Few of us have visited 
 other countries; not many have seen the more 
 mountainous part of our own; scarcely one pre- 
 sent, perhaps, knows the internal history of the 
 spot which now supports him. We generally know 
 that it principally consists of clay, even to a con- 
 siderable depth ; but the greater part have yet to 
 learn that this clay has unquestionably been de- 
 posited by the sea, that it encloses tea-shells, and 
 that the whole country surrounding us to a con- 
 siderable depth and extent, is the debris, or ruin 
 of rocks. 
 
 It seems to me that we cannot do better than 
 begin our inquiries into the nature of such coun- 
 tries as those in which we live of low and level 
 countries ; from which we may rise to the con- 
 sideration of those somewhat more elevated, and 
 
71 
 
 thence to that of the nature and component masses 
 of mountainous regions. 
 
 But level countries are so little open to the 
 investigation of the geologist ; and seem to afford, 
 when compared with the more obvious masses of 
 mountains, so little to attract his attention and 
 research, that the nature of the larger tracts of 
 such country i but little understood. Mineral 
 beds and veins are, for the most part, situated in 
 hiils, or eminences of more considerable elevation ; 
 to these, therefore, the attention of the miner and 
 the mineralogist, as well as of the geologist, has 
 hitherto been principally directed : the component 
 masses of mountains are known the best. During 
 the short period that mineralogy and geology have 
 ranked among the sciences, they have made rapid 
 advances : within the present century, considera- 
 ble attention has been giren to the exploring of 
 some tracts of level country, which have amply 
 paid the research. From the actual nature of 
 these, we may reason by analogy of the rest. 
 
 In Europe, the principal tracts of low country 
 are the eastern parts of England, the Netherlands, 
 and the northern parts of France and Germany, 
 and the whole of Poland. In Asia, the north-east 
 parts of Russia, called the Steppes. In America, 
 there are vast tracts of low land, through which 
 the Mississippi and Missouri rivers take their 
 course. The extent of the low lands of Africa 
 are not ascertained. 
 
 From what is actually known, however, it may 
 
72 
 
 be asserted that the lowest and most level parts of 
 the earth, when penetrated to a very great depth, 
 exhibit horizontal strata, composed of various 
 substances, and containing, almost all of them, in- 
 numerable marine productions. Similar strata, 
 with the same productions, compose the hills even 
 to a considerable height. The shells are some- 
 times so numerous as to constitute the entire 
 body of the stratum ; they are often in so perfect 
 a state of preservation as that their sharpest 
 ridges are retained ; they are found in eleva- 
 tions far above the level of the ocean, and in 
 places to which the sea could not be conveyed by 
 any existing cause : they are sometimes enclosed 
 in loose sand, sometimes filled or penetrated by 
 the hardest stones. Every , part of the earth, 
 every continent, and almost every island exhibits 
 the same phenomenon. 
 
 It was once, long ago it is true, asserted that 
 these remains of shells and other organized bodies, 
 were merely the sports of nature; but it has been 
 frequently found that the nicest and most scrupu- 
 lous comparison of their forms, cannot detect the 
 slightest difierence between some of these shells, 
 and the shells which still inhabit the sea. They 
 have therefore once lived in the sea, and been 
 deposited by it ; the sea must consequently have 
 rested in the places where the deposition has 
 taken place. Hence il is evident that the basin 
 or -resriYoir containing the sea has undergone 
 
some change at least, either in extent, ,in situation,, 
 or in both. 
 
 The traces of revolutions become still more 
 apparent and decisive if we ascend a little higher, 
 and approach nearer to the foot of great chain* 
 'of mountains ; still many beds of shells are found, 
 some even larger and more solid, quite as nume- 
 rous and welPpreserved, but not of the sams- 
 species as those found in less elevated region?. 
 Here the strata that contain these shells, are of 
 various degrees of inclination, and sometimes in- 
 stead of being horizontal, as in plains and low 
 hills, are even vertical. The strata of great 
 chains of mountains, of whatever composed, or 
 however placed, are laid open to view by means 
 of vallies which time and violence have produced. 
 
 The diversity existing in the inclination of 
 strata, clearly points out, in the estimation of some 
 geologists, that by some means these have been 
 broken and overturned. 
 
 The operation of an agent equal to the break- 
 ing up and overturning of the strata of mountains, 
 and, if I may so say, to the destruction of rocks, 
 and to the forming anew whole tracts of coun- 
 try which enclose the remains of organized bodies, 
 was, it cannot be doubted, equal io the disruption 
 of vast portions of continents, thereby forming 
 islands : and it must, in all probability, have alinuM- 
 universally changed in appearance, and even in 
 form, the surface of the globe. 
 
 It is beyond a doubt, that there have been 
 H 
 
74 
 
 catastrophes of the same nature, though not per- 
 haps to the same extent. What has been the 
 agent employed in the production of these catas- 
 trophes, is most obvious. It is not to be doubted 
 that there have been successive irruptions and 
 retreats of the sea ; and it seems equally certain 
 that the final result has been the universal de- 
 pression of its level. 
 
 As we ascend to still higher points of elevation, 
 and advance towards the lofty summits of moun- 
 tains, the remains of marine animals, and that 
 multitude of shells already spoken of, begin to 
 grow rare, and, at length, disappear altogether. 
 We arrive at strata of a very different nature, 
 which contain no vestige of living creatures ; 
 nevertheless, certain circumstances observable in 
 all these strata, in which not a trace of organic 
 remains is to be found, have induced some geolo- 
 gists to suppose that their bare and rugged sum- 
 mits, though elevated far above the strata contain- 
 ing shells, have also been moved or overturned. 
 
 But though, by some, these rocks are not con- 
 sidered to be precisely in the place and position 
 in which they were originally deposited, they are, 
 nevertheless, considered by geologists to be older 
 than all other rocks ; because, as they contain no 
 animal remains, it seerns reasonable to suppose 
 that they remain unaltered, in the same state as 
 that in which they were created ; and they have 
 consequently received from geologists the name 
 io primitive rocks. 
 
75 
 
 Rocks of this description rise through others at 
 various elevations in every quarter of the globe ; 
 but in their greatest elevation, primitive moun- 
 tains traverse our continent in various directions, 
 rising above the clouds ; separating the basins of 
 rivers from each other, and serving, by means of 
 their perpetual snows, as reservoirs for feeding 
 the springs ; and forming, in some measure, t}ie 
 skeleton, or, as it were, the rough frame-work of 
 the earth. 
 
 I shall here recapitulate what has just now been 
 aid 5 and shall afterwards proceed to its elucida- 
 tion, by adducing such proofs, drawn from the ob- 
 servations^of men who have made the phenomena 
 of the globe their study, as may be consistent with 
 the nature of the subject and our present object. 
 
 3. That the lowest and most level parts of ti-e 
 earth consist of horizontal strata, composed of 
 various substances, many of them containing 
 marine productions. 
 
 2. That similar strata are found in hills to a 
 great height. 
 
 3. That shells are sometimes so numerous as 
 to constitute entire strata. 
 
 4. That shells are found in elevations far 
 above the level of the sea, and at heights to which 
 the sea could not be raised by any existing 
 cause. 
 
 5. That these shells once lived in the 
 were deposited by it, 
 
0. That shells continue to be found as we 
 s *ise to the foot of great chains of mountains. 
 
 7. That, at this elevation, the strata, instead 
 of being horizontal, as in plains, are of various 
 degrees of inclination, and sometimes vertical. 
 
 8. That, from these and other circumstances. 
 it irf inferred that there have been frequent irrup- 
 tions and retreats of the sea. 
 
 9. That, as we approach the summits of lofty 
 mountains, the remains of marine animals and 
 aiiells become rare, and even wholly disap- 
 pear. 
 
 10. That their strata are wholly different, and 
 contain no vestige of a living creature. 
 
 11. That these strata are, by some, considered 
 not to be precisely in the place in which they 
 were formed. 
 
 12. That, nevertheless, as they contain no 
 vestige of animal remains, they are considered 
 to be the oldest rocks, and therefore are called 
 primitive. 
 
 The consideration of these points will naturally 
 involve inquiries into others which may be termed 
 subsidiary to them. In order, however, to form a 
 complete outline of Geology, it will be necessary 
 to add to these a number of other inquiries, more 
 completely within the province of the mineralogist. 
 Of these I shall now present an outline ; and 
 after attempting an elucidation of the foregoing, 
 I shall, in like manner, proceed with these, and 
 present to your notice the experience and obser- 
 
77 
 
 vatlons respecting them, of men who have studi- 
 ously investigated the phenomena of the globe. 
 
 13. That rocks, which, because they include 
 no vestige of animal remains, are termed primi- 
 tive, are of various kinds. 
 
 14. That rocks enclosing animal remains, are 
 never found underneath, or supporting, those 
 rocks which are termed primitive. 
 
 15. That some primitive rocks alternate with 
 each other r but that granite is found beneath 
 all others, and frequently overtops all the 
 rest. 
 
 16. That rocks which include organic re- 
 mains must have been formed after the shells 
 they contain ; and therefore, not being considered 
 primitive, are by some termed secondary "rocks : 
 whence the terms, used by geologists of primary 
 and secondary formations. 
 
 17. That there are many varieties of secondary 
 rocks, each of which has received a geological 
 appellation. , 
 
 18. That there exists another class of sub- 
 stances not appropriately termed rocks; but 
 which, being considered to be the debris or ruin 
 of rocks, by their long exposure to the action of 
 air and water, or both, are therefore termed allu- 
 vial deposit es. 
 
 I now proceed to the illustration of the first 
 position, viz. 
 
 That the lowest and most level parts of the 
 earth consist of horizontal strata, composed of 
 H2 
 
78 
 
 various substances, many , of them containing 
 marine productions. 
 
 The illustrations necessary to this position 
 will include many of the newest, most striking, 
 and most important geological facts. These facts 
 will prove, to a limited extent, another of our 
 assertions, namely, that the catastrophes to which 
 the surface of the globe has been subject have 
 been numerous : and it will be shown that some 
 of these have not been owing to irruptions of 
 the sea, but to the agency of fresh water ; and it 
 will clearly appear that these irruptions of fresh 
 and salt water have been alternate. 
 In order to make the whole of these circum- 
 stances more intelligible, it will be requisite a 
 little to anticipate, by adverting, here, to some 
 geological facts, which, according to our previ- 
 ous arrangement, would belong to another place. 
 Geologists, who have had ample opportunity of 
 examining mineral deposites in large and moun- 
 tainous tracts of country, have satisfactorily 
 ascertained that certain deposites are always 
 found beneath, never above, certain other depo- 
 sites. Investigation has proved that rocks which 
 contain no animal remains are always found be- 
 neath, never resting upon those rocks which do 
 contain animal remains : and also that those depo- 
 sites which are termed alluvial ', as gravel, sand, 
 clay, &,c. are never found beneath other rocks, 
 but always resting upon them. 
 
 Thus much jt seems necessary to premise of geo- 
 
70 
 
 logical fact, previously to entering on a detail of 
 the extraordinary circumstances which I shall ad- 
 duce to prove the truth of our first position. 
 
 An investigation of the country surrounding 
 Paris to a considerable extent, which by compa- 
 rison may be termed low and level, has lately 
 been accomplished by the eminent naturalist 
 Cuvier, associated with the acute geologist Brong- 
 niart, and they have published a masterly deli- 
 neation of the geological structure of the country. 
 
 Now as chalk makes its appearance on the edge 
 of this district, and almost surrounds Paris, though 
 at a considerable distance from it ; and as the sur- 
 rounding chalk is found to dip beneath the soil, 
 or alluvial matter within the district, and has in 
 many places, and at various depths, been discover- 
 ed far beneath its surface, by the sinking of welle 
 and pits ; it is justly concluded that the soil on 
 which Paris stands, and the surrounding country 
 to a great extent, was actually deposited in a 
 large hollow consisting of chalk, which, therefore, 
 has been termed by Cuvier and Brongniart the 
 chalk basin of Paris. 
 
 Immediately covering the chalk is found a small 
 stratum of plastic clay, used in the manufactory 
 of different kinds of pottery. On the plastic clay 
 rests a deposite by salt water, thence termed a 
 marine formation : above this rests a deposite by 
 fresh water, thence termed afresh water formation : 
 next above is found a second marine formation : 
 above it, a second/resA water formation ; and upon 
 
80 
 
 this rests an alluvial deposits. I now proceed to 
 
 a more particular description of the nature of 
 
 these five deposites : 
 
 1st deposits. On the plastic clay covering the 
 bottom of the chalk basin, it has been said that 
 the lower marine formation rests. It consists 
 of coarse limestone abounding in marine petri- 
 factions : associated with it, is a series of strata 
 in regular order, as marl, sandstone, kc. all of 
 which enclose marine shells, many of them stiJi 
 retaining their pearly lustre. Occasionally, the 
 space usually occupied by the limestone and 
 the series of other strata, is entirely filled with 
 siliceous limestone without shells, resting on 
 the plastic clay and supporting the deposite 
 about to be described. 
 
 2d deposits. Upon the above marine formation,, 
 rests a deposite by fresh water. It consists of 
 gypsum covered by a bed of white friable marl, 
 enclosing petrified wood of the palm kind, and 
 the remains of fishes and shells ; the gypsum 
 contains remains of extinct quadrupeds, birds, 
 amphibious animals, fishes and shells, all of 
 which are of land or fresh water species. This 
 deposite is therefore called the lower fresh water 
 formation. 
 
 In the Gypsum, Cuvier discovered, the hones of 5 varieties of an 
 extinct animal, which he calls the pafceufAorum, (signifying ancient 
 large aniiml.) varying in size from a siirc-..; ta horse; and the 
 bcries of 5 varieties of another extinct anirnsl, vrhic!) he calls the 
 , (signifying beast without weapon: ; it h:ul no cauine 
 varying iu size fiorn the hoise to tiu. a,^. Boll; iiies species 
 
81 
 
 he coasidersto have been natives of the county over which Paris, is 
 now built. 
 
 He also fo;md the bones of an unknown species cf the dog, and 
 
 of lite fox; also of an ichneumon double the size *of the living <;pe- 
 
 . Nearly an entire skeleton of a quadruped of the genus didd- 
 
 I'hls was aKo found, but cot belonging to any of the existing epe- 
 
 cics, which are natives of A merka. 
 
 The fossil bones of birds, are not so readily known n. those of other 
 animals ; but Cuvier describes some, found along with the bones of 
 the extinct animals, as belonging to the pelican, the starling, and the 
 quail tribe?. 
 
 Of amphibious animals, the bone's of the tortoise and the crocodile 
 are recognised. 
 
 Of fossil fish, there are 5 varieties ; most of them are allied to the 
 present species of fresh water fish. 
 
 The shells all belong to fresh water fish. 
 
 Sddeposite. Above the beds of gypsum and marl, 
 just described as containing the remains of fresh 
 wetter animals, lie two beds of oyster-shells, se- 
 parated by a bed of sand and sandstone with- 
 out shells, from a bed of sand and sandstone, 
 containing marine shells. These seem to have 
 formed but one deposite by salt water. 
 
 The two beds of oyster shells are separated 
 by a thin bed of white marl. The shells of the 
 lower bed are numerous, thin, small, and brown. 
 The upper bed of oyster-shells is very thick, 
 and the shells are arranged as they are found 
 in the ocean : the greater number of them are 
 whole, and have both valves. 
 
 On the bed of sand and sandstone above 
 described, rests a bed of clayey sand and marl, 
 in which lies the btthrstone, or millstone. As 
 it contains neither vegetable nor animal re- 
 
82 
 
 mains, it seems not sufficiently characterized 
 to be referred decidedly either to the preced- 
 ing, which is a marine formation, or to the 
 succeeding deposite, which is a fresh water 
 formation. 
 
 4th deposite. Above the buhrstone or millstone, 
 lies a deposite of limestone and of siliceous 
 substances, as flint, pitchstone, and jasper. The 
 siliceous matter is sometimes allied in charac- 
 ter to the millstone. But the essential charac- 
 ter of the whole of the deposite, is, that it con- 
 tains fresh water and land shells, nearly all of 
 which belong to the genera now living in mo- 
 rasses. This formation extends 30 leagues to 
 the south of Paris. 
 
 5th deposite. Above the four depositea just de- 
 scribed, as being alternately from fresh and salt 
 water, lies the alhwial deposite, which appears 
 to be by fresh water, and is composed of vari- 
 ously coloured sand, marl, and clay. It con- 
 tains rolled stones of various kinds, but is most 
 remarkable for its enclosing the remains of 
 large organic bodies: in it arc found great 
 trunks of trees, bones of elephants, of oxen, 
 rein-deer, and other large land animals. 
 This account of the contents of the 1'aris chalk 
 basin contains important geological information, 
 The space to which this investigation was limited, 
 is, indeed, small, when compared with the surface 
 of a globe of 25,000 miles in circumference, one- 
 third of which is land. And if the investiga- 
 
. 83 
 
 tion of so small a comparative spot, should not be 
 deemed conclusive in regard to the probable na- 
 ture of low and level countries in general, we 
 have only to refer to the natural history of other 
 parts of France and of other countries ; of Ger- 
 many, and of many tracts in the north of Europe, 
 to be convinced,, that at least in degree, the same 
 effects have been almost universal. 
 
 But it was no longer ago than in the last year, 
 that a geological investigation of certain districts 
 in our country,* gave an evidence, in most points, 
 perfectly coinciding with the observations of 
 Cuvier, in regard to the chalk basin of Paris. 
 The minutije of this investigation were detailed 
 in a very interesting communication to the Geo- 
 logical Society, since published in the 2d volume 
 of its Transactions. At present we cannot do 
 more than notice its results. 
 
 It appears that in this country there are two 
 chalk basins, in a greater or lesser degree resem- 
 bling that of Paris. One of them is called the 
 Isle ofll r ight basin ; the other, the London basin. 
 
 The hie of Wight basin comprehends the dis- 
 trict between Newport in that Island on the 
 south, Southampton on the north, Brighton on 
 the east, and Dorchester on the west. The strata 
 which cover the chalk in this district, are indi- 
 vidually and collectively of various thicknesses; 
 occasionally only two or three of them are found, 
 
 * By T. Webster, M. G. S. 
 
84 
 
 , 
 
 and sometimes only one of them ; but there i* 
 one place on the southern edge of this basin, 
 which proves beyond a doubt that the same causes 
 which operated in the Paris basin, extended their 
 influence to the Isle of Wight, and probably at 
 the same period of time. 
 
 The place to which I allude is Headen Hill, 
 forming a part of Alum Bay, near the western 
 angle of the Isle of Wight. Of this hill, which is 
 about 300 feet high, a natural section has been 
 laid open, since its deposition, doubtless by the 
 sea which borders it. Any one may, therefore, 
 easily satisfy himself that it contains the same 
 description of strata as have been found in the 
 Paris basin, and precisely in the same order ; 
 that is to say, alternate salt and fresh water depo- 
 sflesy enclosing shells perfectly similar to those 
 found in the Paris basin. Of the truth of this we 
 have evidence. It is ascertained by a compari- 
 son of the shells taken from the corresponding 
 deposites in both basins ; and the animal remains 
 HO compared, are now deposited in the collec- 
 tion of the Geological Society in London. 
 
 The London ' asin begins at Deal, in Kent, and 
 extends (not in a right line) by Canterbury to 
 Gravesend; comprebending the whole of Kent 
 north of that line, except the Isle of Thanet, 
 which is of chalk. The edge of the basin from 
 Gravesend crosses the Thames at Grays, extends 
 to Purfleet, whence it crosses the Thames again, 
 and passes nearly in a strait line to Guild ford, and 
 
85 
 
 from Guildford to a little west of Hungerford, in 
 Berkshire, whence it turns nearly north-east, to 
 Maidenhead, Eaton, Watford, Hertford, Stansted, 
 and Thaxted ; but its precise extent to the north 
 of that place, is not ascertained. In a word, how- 
 ever, the chalk basin in which London is situated, 
 is comprehended in an acute triangle, one of its 
 longest sides extending from Hungerford some- 
 what to the north of Harwich, the other from 
 Hungerford to Deal ; its shorter side taking in 
 the whole coast from the north of Harwich to 
 Deal, with the exception of the Isle of Thanet. 
 
 The perfect coincidence of the London with the 
 Paris and Isle of Wight basins, has not yet been 
 quite satisfactorily ascertained, in regard to the 
 alternate depositions by salt and fresh water. 
 The stiff blue clay, which prevails to so great a 
 depth almost every where round and beneath 
 London, is unquestionably a marine depositc, as 
 all its numerous animal remains are those of sea 
 animals. This clay lies immediately under the 
 fine bed of gravel on which London is built. The 
 wells in London pass through this clay from 200 
 to 300 feet; at Tottenham, about 130; at Lord 
 Spencer's, at Wimbledon, 430 feet : at Harrow on 
 the Hill, 70 feet ; at Primrose Hill, near Hamp- 
 stead, 500 feet without success ; and, except in 
 the latter instance, all arrived at the same bed of 
 white sand, from which the water rose. 
 
 By a paper lately read before the Royal Society, 
 we find, that, at Brentford, they lately passed 200 
 I 
 
86 
 
 feet through the stiff blue London clay, without 
 arriving either at water or chalk : above the clay 
 lies a stratum of sand, gravel, and water; over 
 that another, of 1 to 9 feet of loam ; then 7 feet 
 of sandy gravel ; and then above, 9 feet of loam. 
 These strata lying over the day contain a vast 
 collection of the bones of elephants, both African 
 and Indian, of the hippopotamus, the horns and 
 jaws of oxen, the horns of deer, and both land and 
 fresh water shells. These circumstances clearly 
 prove these deposites to have resulted from fresh 
 water ; whereas the day on which they rest con- 
 tains only the remains of sea animals. It is there- 
 fore probable, that a perfect accordance between 
 the contents of the London and Paris basins will 
 hereafter be satisfactorily ascertained. 
 
 In the strata above, as well as in those below 
 the chalk, in the north-eastern parts of England, 
 there is a remarkable agreement in point of posi- 
 tion, in several places ; in some, one or more of 
 the strata may be wanting, but the order in which 
 they lie seems never to be inverted. 
 
 If, however, we would take a wider range for 
 proofs of that more general existence of these 
 catastrophes that have befallen the surface of the 
 globe, we shall easily find conviction. We are 
 speaking now only of those to which the lower 
 and most level parts of the earth have been sub- 
 jected. 
 
 The bones of a species of rhinoceros, different 
 from either of the three species of Africa, Asia, 
 and the Isle of Sumatra, have been dug out of the 
 
87 
 
 alluvial soil near Canterbury ; and since, in many 
 places of Germany, France, and Italy. In Siberia, 
 not only single bones and skulls, but the whole 
 animal, with flesh and skin has been discovered. 
 In the alluvial soil of France and Italy, have 
 been found the bones of an hippopotamus, allied 
 to the two only species now known, inhabitants of 
 Africa and Sumatra; as well as the bones of ano- 
 ther animal not allied to these, and entirely differ- 
 ent from any of the existing species of quadrupeds. 
 The tapir is an animal peculiar to South Ame- 
 rica, yet two fossil species have been found in 
 Europe ; the one small, the other gigantic : both 
 have occurred in different parts of France, Ger- 
 many, and Italy. 
 
 Of the elephant, the only existing species are 
 those of Africa and Asia. One fossil species has 
 been discovered, differing from each, but most 
 nearly allied to the Asiatic. It is the mammoth 
 of the Russians. The bones of the mammoth 
 have been found in the alluvial soil near London, 
 Northampton, Gloucester, Harwich, Norwich, in 
 Salisbury plain, and in other places in England ; 
 they also occur in the north of Ireland; and in 
 Sweden, Iceland, Russia, Poland, Germany, 
 France, Holland, and Hungary, the bones and 
 teeth have been met with in abundance. Its teeth 
 have also been found in North and South America^ 
 and abundantly in Asiatic Russia. Pallas says, 
 that from the Don to the Tchutskoiness, there is 
 scarcely a river that does not afford the remains 
 
88 
 
 of the mammoth, and that they are frequently 
 imheddc-d in alluvial soil, containing marine pro- 
 ductions ; the skeletons are seldom complete, still 
 more seldom is the fleshy part of the animal pre- 
 served : but an interesting instance of this has 
 been described.* 
 
 Five species of an animal mope nearly allied to 
 the elephant than to any other living species, have 
 also been discovered : it has been called the mas- 
 todon. The five species are all herbivorous, the 
 largest is about the size of the elephant ; but no 
 living species of the mastodon has been discover- 
 ed in any part of the world; the fossil remaini 
 were found in Europe and America. 
 
 All these fossil species of quadrupeds have oc- 
 curred in alluiial soil that corers the bottoms of 
 vallies,. or is spread over the surface of plains ; 
 none have been found in high vallies : the bones 
 of some were covered by marine shells and remains, 
 others by fresh water shells ; and as no remains of 
 these animals have been seen in any solid rock, 
 or in any high mountain, it seems probable that 
 these animals fell victims to some of the latest 
 catastrophes that have befallen the globe ; and 
 though some of them differ from their co-species 
 now existing in the torrid zone, there seems some 
 
 * The following account of tbe singular discovery of the carcase of a 
 mammoth, is given by professor Cuvier, as taken from a report in the 
 supplement to the Journal du Nord, No. 80, by M. Adams, Adjunct 
 member of the Academy of St. Petersburg. 
 
 4 ia the year 1799, a Tungusian fisherman observed a strange shflp- 
 
83 
 
 reason for supposing them to have been inhabit- 
 ants of the regions in which their bones arfe 
 
 less mass projecting from an left-bank, near the niouth of a river in the 
 north of Siberia, the nature of which lie did not understand, aod whicli 
 was so high in the bank as to be beyond his reach. H* went next year, 
 observed the same object, which was then rather more disengaged from 
 among the ice, but was still unable to conceive what it was. Towards 
 the end of the following summer, 1801, he could distinctly see that it 
 was the frozen carcase of an enormous animal, the entire flank of which 
 and one of its tusks had become disengaged from the ice. In conse- 
 quence of the ice beginning to melt earlier and to a greater degree than 
 usual in 1803, the fifth year of this discoveiy, the enormous carcase 
 became entirely disengaged, and fell down from the ice-crag on a sand- 
 bank, forming part of the coast of the Arctic Ocean. In the month of 
 March, of that year, the Tungusian carried away the two tusks, which he 
 sold for the value of fifty rubles ; and at this time a drawing was made 
 of the animal, of which I possess a copy. 
 
 ' Two years afterwards, or in 1806, Mr. Adams went to examine this 
 animal, which still remained on the sand-bank where it had fallen front 
 the ice, but its body was then greatly mutilated. The Jukuis of the 
 neighbourhood had taken away considerable quantities of its flesh to feed 
 their dogs ; and the wild animals, particularly the white bears, had also 
 feasted on the carcase ; yet the skeleton remained quite entire, exeept 
 that one of the forelegs was gone. The entire spine, the pelvis, one 
 shoulder-blade, and three legs, were still held together by their ligaments 
 and by some remains of the skin ; and the other shoulder-blade was found 
 ot a short distance. The head remained, covered by the dried skin, 
 and the pupil of the eyes was still distinguishable. The brain also re- 
 mained within the skull, but a good deal shrunk and dried up; and one 
 of the ears was in excellent preservation, still retaining a tuft of strong 
 bristly hair. The upper-lip was a good deal eaten away, and the under- 
 lip was entirely gone, so that the teeth were distinctly seen. The animal 
 wa a male, and had a long mane on its neck. 
 
 * The skin was extremely thick and heavy, and ag much of it remain- 
 ed as required the exertions of ten men to carry away, which they did 
 with considerable difficulty. More than thirty pounds weight of the hair 
 and bristles of this animal wre gathered from the wet sand-bank, having 
 been trampled into the mud by the white bears, while devouring the 
 *arcase. Some of the hair was presented to our Museum of Natural 
 History, hy M. Targe, censor in the Lyc-um of Charlemagne. It ton- 
 
 I 2 
 
96 
 
 found. The mammoth found whole in Siberia 
 was too warmly clad for the torrid zone. 
 
 Additional proofs of the extensiveness of thtst 
 catastrophes, both by salt and fresh water, may be 
 found in the famous rock of Gibraltar, and at va- 
 rious places on the coast of the Mediterranean. 
 
 The rock of Gibraltar is principally limestone, 
 and is traversed by fissures or hollowed into caves, 
 which contain a peculiar compound mass, con- 
 sisting of angular fragments of limestone, of bones, 
 usually of ruminating animals, generally broken, 
 never in skeletons; and of land shells, cemented 
 together by a calcareous basis : the bones were 
 for a long time thought to be those of monkeys, 
 but Cuvier has, with his peculiar sagacity, consi- 
 dered some of them to belong to a species of an- 
 telope, others to a kind of mouse. 
 
 At Cette, the limestone includes bones like 
 those of a rabbit; others similar to those of the 
 field mouse, and of a bird of the sparrow tribe ; 
 the vertebras of a serpent, together with the bones 
 of some ruminating animal, and three various 
 kinds of land shells. 
 
 istg of three distinct kinds. One of these is stiff black bristles, a foot 
 or more in length; another is thinner bristles, or coarse flexible hair, of 
 reddish-brown colour ; and the third is a coarse reddish-brown wool, 
 which grew among the roots of the hair. These afford an undeniable 
 proof, that this animal had belonged to a race of elephants inhabiting a 
 old region, with which we are now unacquainted, and by no means fitted 
 fc> dwell in the torrid zone. It is also evident that this enormous animal 
 u*t have been frozen up by the ice at the moment of its death. 
 
91 
 
 At Nice and the Jntibes, the rock also contained 
 the bones of the horse. 
 
 At Corsica, the rock contains the bones of 
 small quadrupeds, chiefly foreign to the place ; 
 as those of one inhabiting the coldest and wildest 
 parts of Siberia; and enormous quantities of bones, 
 some of which resemble those of the field mouse, 
 and others those of the water rat. 
 
 In Dalmatia, the bones contained in the rock 
 are principally like those of Gibraltar. 
 
 At Concud, in Arragon, the rock contains the 
 bones of the ox, ass, a small kind of sheep, and 
 many land and fresh water shells. 
 
 We have now, as it seems to me, satisfactorily- 
 proved our first position to a considerable extent, 
 viz. ' That the lowest and most level parts of the 
 earth, consist of horizontal strata, composed of 
 various substances, many of which contain marine 
 productions.' 
 
LECTURE IV. 
 
 Organic Remains visible in hills and on the sides of elevated mountains 
 Strata of the Brocken mountain Summits of lofty mountains con- 
 tain no organic remains Heights of mountains Division of rocks irita 
 primitive, transition and flcetz (or secondary) and alluvial Their de- 
 finitions. 
 
 ON the last evening, the real objects of Geo- 
 logical inquiry were pointed out. It was shown 
 that these consist of the natural phenomena and 
 facts every where discoverable ; and that without 
 an ample and nice investigation of these, it is 
 impossible for us ever to attain a reasonable 
 knowledge of the earth : such a knowledge, I 
 would say, as may be derived from some acquaint- 
 ance with the component masses of its crust, and 
 of their relative positions. It was also shown 
 how incapable and absurd are the speculations of 
 mere closet-philosophers; who, relying on their 
 inventive powers, and on the extreme difficulty 
 of contradicting their silly theories, indulged 
 themselves in speculations scarcely more ridicu- 
 lous than it would be to assert that the globe is 
 an egg or an oyster. 
 
 During the last evening also, were laid down 
 a series of geological positions, as they may be 
 termed, which have been found to result from the 
 
93 
 
 truly philosophical labours of men who have in- 
 vestigated the crust of the globe, perhaps to as 
 great a height and to as great a depth, above and 
 beneath the surface of the sea, as man can easily 
 attain. These geological positions I proposed to 
 illustrate by quoting the experience of the very 
 men from whose labours they have resulted. The 
 first of them, viz. * That the lowest and most level 
 parts of the earth, when penetrated to a great 
 depth, exhibit nothing but horizontal strata, com- 
 posed of various substances, and containing almost 
 all of them innumerable marine productions,' was 
 then elucidated by the investigation of the chalk 
 basin of Paris, and of the chalk basins of London, 
 and of the Isle of Wight : and not only the truth 
 of the foregoing position was made clearly to ap- 
 pear, but also the novel and interesting facts, that 
 in these basins there have been successive and al- 
 ternate deposites from salt and fresh water ; which 
 is proved by the nature of their strata, and the 
 organic remains they respectively contain. And 
 it was further shown that these catastrophes, so 
 fatal to animal life, have not been partial; inas- 
 much as they are readily and largely seen in al- 
 most every part of the European continent, and 
 particularly on the coasts of the Mediterranean 
 sea. 
 
 The object of our present inquiry into the 
 nature of the constituent masses of the surface of 
 the globe, is so extensive as not to admit of those 
 immediate convictions of the truth of what may 
 
34 
 
 be asserted respecting them, as might be desirable. 
 I claim however this advantage ; I demand no 
 assent to theory, for I will not broach a theory. I 
 offer alone the results of inquiries among ibe facts 
 and phenomena of nature, by men whose love of 
 nature and of truth, has rendered their researches 
 invaluable to science : researches amid regions 
 always open to the investigations of the doubting 
 or disbelieving. Amongst these men, let us re- 
 member that we have an Humboldt r a Werner, a 
 Saussure, and a Cuvier. What but the love of 
 truth and of science could have induced Humboldt 
 to traverse whole continents, or to ascend the 
 Andes more than 18,000 feet above the level of 
 the sea ; or Werner, the great German geologist, 
 to bestow his life in examining the rude and 
 mountainous regions which surrounded him, and 
 in teaching the results of his inquiries ? What but 
 the love of truth and of science could have led 
 Saussure to investigate every corner of the Alps, 
 during twenty years ; or have induced Cuvier to 
 bestow twenty-five years of his life in the sludj 
 of comparative anatomy and osteology, with a 
 riew principally, if not solely, to the illustration 
 of the nature of our globe? 
 
 If from all that Humboldt, and Werner, and 
 Saussure, and Cuvier. and many other intelligent 
 geologists, have observed, in regard to the nature* 
 and respective positions of the great masses form- 
 ing the crust of the earth, we were to select such 
 parts as would immediately come in evidence of 
 
95 
 
 the truth of the geological positions already sub- 
 mitted to your notice, scarcely fifty evenings 
 would afford time sufficient for their recital. It 
 is my object to bring the required evidence into 
 the narrowest compass ; I shall, therefore, select 
 only such as may suffice to attain our object ; 
 taking care, at the same time, that it shall be of 
 the most obvious kind that the nature of our in- 
 quiry will permit. 
 
 The positions already recited, begin with the 
 lowest and most hid parts of the earth 5 these we 
 have considered. We now ascend a little, that is 
 to say, to the hills; and after a short notice of 
 their nature, shall rise to the consideration of the 
 masses constituting lofty mountains ; taking occa- 
 sion, here, to present an outline of the divisions 
 which the experience of geologists has taught 
 them to make in rocks, as the component masses 
 of the crust of the globe ; showing the reasons for 
 their division into primitive, transition and floetz, 
 (or secondary) and alluvial ; and that of each of 
 these there are many varieties. 
 
 The 2d position is, That strata containing 
 shells are found in bills to a great height. 
 
 3d. That the shells are sometimes so nu- 
 merous as to constitute entire strata. 
 
 4th. That shells are found in elevations far 
 above the lei'el of the sea, and at heights to 
 which the sea could not be raised by any existing 
 cause. 
 
96 
 
 5th. That these shells once lived in the sea, 
 and were deposited by it. 
 
 6th. That shells continue to be found as we 
 rise to the foot of great chains of mountains. 
 
 These positions I purpose to consider together. 
 The evidence of facts requisite for their support, 
 and as proofs of their truth, need not detain us 
 long. 
 
 The cliffs of the Isle of Sheppey, bordering our 
 own river, the Thames, do not rise to any con- 
 siderable height above the level of the water. 
 They have, however, long been celebrated for the 
 numerous organic remains found in them, a list 
 of which, was published several years ago. This 
 list has since been enriched by a gentleman now 
 resident at Faversham, by the addition of above 
 700 different species of fossil fruits, berries, and 
 ligneous seed vessels. Among the animal remains 
 found in these cliffs, are several varieties of the 
 crab, the jaws of crocodiles, and lobsters nearly 
 whole. It deserves notice that all these remains, 
 both vegetable and animal, are entirely impreg- 
 nated with sulphuret of iron, or pyrites. 
 
 At Reading, in Berkshire, or rather in the ele- 
 vated lands in its neighbourhood, are found con- 
 siderable deposites of oyster-shells ; it is remark- 
 able that many of them are entire, having both their 
 valves united ; but the animal matter, or oyster, 
 is perfectly decayed. These shells have not un- 
 dergone the process of petrifaction ; they are white 
 and extremely brittle, and readily separate into 
 
97 
 
 laminae. At Touraine, in France, 100 miles from 
 the sea, and about 9 feet under the surface, there 
 is a bed of shells ** leagues long, and about 20 
 feet thick. According to Ulloa, there are similar 
 deposites in Peru. Such are likewise well known 
 to exist in almost every part of Europe. In the 
 neighbourhood of Bath, at a rather higher ele- 
 vation, large tracts of limestone are found, con- 
 sisting almost wholly of shells ; which are also 
 discoverable in great abundance in the Glouces- 
 tershire hills, and in other parts of England. In 
 the cliffs near Whitby, a crocodile has been found ; 
 in those near Lyme, in Dorsetshire, their remains 
 occur in considerable abundance ; and in the chalk 
 cliffs of Dover, some varieties of fossil shells. 
 Still higher, in various parts of Germany, the fos- 
 sil remains of fish are found in hills and rocks oi 
 various kinds of slate. 
 
 I Let us, however, continue to ascend. Dolomieu 
 found immense quantities of sea shells on the 
 sides of Mount ^Etna, 2000 feet above the level 
 of the sea ; and at the height of 2400 feet above 
 the same level he found, in the mountain itself, 
 ' regular strata of gray clay enclosing sea shells. 
 
 Some of the lower hills of the Appennine chain, 
 contain many species of shells; they contain also 
 the fossil bones of elephants, of rhinoceroses, of 
 the hippopotamus, of whales, and of dolphins. 
 
 It is asserted by Cuvier, in regard to the shells 
 which ^are found imbedded in some rocks, that 
 "' A nice and scrupulous comparison of their form's. 
 K 
 
SB 
 
 of their contexture, and even of their composi- 
 tion, cannot detect the slightest difference be- 
 tween some of these shells, and the shells which 
 still inhabit the sea ;' an assertion which perhaps 
 no one, who has at all examined it, will presume 
 to deny. Surely then, we have a right to assume 
 that they once lived in the sea, arid that they 
 were deposited by it ; and if deposited by it, that 
 the sea must have been once sufficiently elevated ; 
 since we know no other cause adequate to the 
 deposition of rocks enclosing sea shells, and to 
 their deposition in regular strata. And when we 
 take into consideration that Mont Perdu, which is 
 the highest of the Appennines, and reaches an 
 elevation of] 1,000 feet above the level of the sea, 
 encloses so immense a quantity of sea shells, as 
 that some of its strata seem almost wholly com- 
 posed of them, we shall at once assent to the po- 
 sition that shells are found in places to which the 
 sea could not be conveyed by any existing cause. 
 
 Mont Perdu is by no means the only elevated 
 mountain enclosing sea shells; it is, however, one 
 of the highest ; and we may readily infer that, if a 
 mountain of so great elevation encloses them, 
 they will be found in the strata at the foot of 
 great chains of mountains. 
 
 According to Saussure, the Buet, a mountain 
 which rises 10,000 feet above the level of the sea, 
 contains no petrifactions ; but the Salenche, the 
 Mole, and others not exceeding 7000 feet, are 
 
99 
 
 found to enclose petrifactions, although they form 
 a part of the same chain. 
 
 The Altain chain of primitive mountains in 
 Siberia enclose no animal remains ; but they are 
 flanked on each side by a chain of hills which en- 
 close marine shells. 
 
 * 
 
 The 7th position is, That at the foot of loft} 
 mountains, the strata, instead of being horizon- 
 tal, as in plains and low hills, are of various de- 
 grees of inclination, and sometimes vertical. 
 
 8th. That, from these and other circum- 
 stances, it is inferred that there have been suc- 
 cessive irruptions and retreats of the sea. 
 
 9th. That as we approach the summits of 
 lofty mountains, the remains of marine animals 
 and shells become rare, and even wholly disap- 
 pear. 
 
 10th. That their strata are wholly different, 
 and contain no vestige of a living creature. 
 
 1 1 th. That their strata are, by some, consider- 
 ed not to be precisely in the place in which 
 they were formed. 
 
 12th. That, nevertheless, as they contain no 
 vestige of animal remains, they are considered 
 to be the oldest rocks, and, therefore, are called 
 primitive. 
 
 In proof that the strata, as we approach the foot 
 af lofty mountains, are not horizontal, as in law 
 
100 
 
 hills, I shall present to your notice the section of 
 a mountain in the Hartz Forest, in Germany, 
 made from the description given by Werner him- 
 self. This mountain is called the Brocken, (see 
 plate 3.) and rises to a considerable elevation, 
 though it is not one of the highest mountains in 
 Europe : but the result of the examination of its 
 surrounding strata by Werner, is better evidence 
 of the facts it discloses than we could perhaps 
 obtain from any other source. The centre is of 
 granite, which is, as it were, mantled all around 
 by several successive and perfectly distinct strata ; 
 the oldest next to the primitive rock; and invari- 
 ably, each succeeding stratum, being newer than 
 the preceding, dips lower and lower, as we depart 
 from the primitive rock around which they are 
 successively deposited. The nature of the several 
 component masses of this mountain, will be fur- 
 ther noticed when we arrive at the consideration 
 of the mineraiogical differences existing in moun- 
 tain rocks. 
 
 The successive deposition of these strata (for 
 that they were successive will become more appa- 
 rent where their geological differences shall have 
 been pointed out) may, at least in degree, be 
 urged in proof that there have been repeated 
 irruptions and retreats of the sea: they will more- 
 over evince that the sea has not always deposited 
 stony substances of the same kind, inasmuch as 
 these deposites are distinct, and even essentially 
 different, in theiv natures : and the strata sur- 
 
101 
 
 rounding this mountain may tie brought in evi- 
 dence, perfectly in agreement with numerous 
 other observations, that the sea has observed a 
 regular succession as to the nature of its dtposites. 
 
 And, from these circumstances/it is reasonable 
 to infer, that the sea has undergone great changes 
 in the nature of its fluid: whence we may pre- 
 sume that there may have been a succession of 
 changes in the nature of the animals which inhabit 
 it, corresponding with the changes in the chemi- 
 cal nature of the sea. 
 
 That such changes have taken place in the 
 natures of the inhabitants of the sea, we have 
 abundant proof. 
 
 Not only do the species and even genera of the 
 shells change with the strata, but it is generally the 
 case that the shells of ancient strata have forms 
 peculiar to themselves ; that these forms gradual- 
 ly disappear ; that they are not found in the strata 
 recently deposited, nor in the existing seas : but 
 the more recent strata enclose some species which 
 the most experienced eye cannot distinguish from 
 those which now inhabit the ocean. 
 
 The section of the Brockcn mountain, shows 
 the reason for our assertion, tbat, as we approach' 
 the summits of lofty mountains, the remains of 
 marine animals and shells become rare, and even 
 wholly disappear. Tt has already been stated that 
 granite, which forms the centre and summit of this 
 mountain, is considered to be the oldest of rocks,, 
 because it is found underneath all others, and fre- 
 K2 
 
10,2 
 
 quently rises through and overtops all other the 
 constituent masses of mountains, as well as be- 
 cause it never contains animal remains ; granite, 
 in like manner, constitutes the highest parts of 
 very many mountains of different elevations 
 throughout the globe. But it is often found that, 
 although in some countries the sides of very lofty 
 mountains have been covered by succeeding stra- 
 ta to a very great height, yet, in other countries, 
 primitive granite, of very inferior elevation, is ex- 
 posed almost to the level of the sea without hav- 
 ing any part of it covered by secondary deposi- 
 tion ; and the fact seems to be that these seconda- 
 ry depositions have greatly varied in extent and 
 in elevation. 
 
 We now come to the consideration of the sum- 
 mits of lofty mountains which contain no vestige 
 of a living creature, and whose stratification, if 1 it 
 may be so called, differs from that of mountains 
 of less elevation. 
 
 The summits of lofty mountains generally con- 
 sist of one or two, and sometimes of alternating, 
 deposites of some of the older rocks; which, for 
 the reasons already given, have been termed pri- 
 mitive. Some of these rocks mostly assume one 
 appearance ; others have mostly an appearance 
 wholly different : I say mostly, because there are 
 but few rocks that always assume the same ap- 
 pearance in regard to stratification. 
 
 For instance, granite, and some other of the 
 
103 
 
 older rocks, sometimes occur in regular and near- 
 ly horizontal strata ; sometimes have no appear- 
 ance of regular deposition, either horizontal or 
 inclined ; but the summits oflofty mountains, con- 
 stituted of such rocks, seem composed of large 
 and irregularly sized blocks, piled on each other 
 without any appearance of order : while on the 
 contrary, gneiss, another primitive rock, is almost 
 invariably in horizontal strata. 
 
 This diversity in appearance is very consider- 
 ably augmented in mountains consisting of alter- 
 nate masses of primitive compounds, which are 
 by no means rare ; and as these rocks suffer, in 
 different degrees, by long exposure to the action 
 of the elements, this circumstance considerably 
 contributes to increase the disorder of their rug- 
 ged summits, which are described as appearing at 
 a distance like the ruins of towers and of fortifica- 
 tions. 
 
 Whether these constituent masses are still in 
 their original position, is a problem of no incon- 
 siderable interest ; nor can we wonder that able 
 geologists should differ on the subject. Cuvier, on 
 the one hand, considers that the very appearances 
 of their summits, are so many proofs of the violent 
 manner in which they hare been elevated. He is of 
 opinion that all the older strata o^ which the crust 
 of the earth is composed, were originally in a 
 horizontal position; and that they have been raised 
 into their present highly inclined position, by 
 
104 
 
 subsidencies that have taken place over the whole 
 earth. 
 
 On the other hand, Jameson (who is a rigid 
 follower of the opinions of Werner, whence we 
 may infer, that it is also Werner's opinion) be- 
 lieves, that the present inclined position of these 
 strata is, in general, their original position ; an 
 opinion which he considers to be countenanced 
 by the known connexion of strata, the phenomena 
 of veins, the crystalline nature of the older rocks, 
 and also by what he terms the great regularity in 
 the direction of strata throughout the globe. 
 
 Since, therefore, two authorities so eminent 
 have not yet decided the point, and since their 
 opinions are directly opposed to each other, we 
 must be content to await and to expect an agree- 
 ment, drawn from yet further inquiries amid the 
 phenomena presented by the grand features of 
 mountain rocks. 
 
 But the researches and experience of many 
 skilful geologists all unite in this : that ike strata 
 composing ike summits of lofty mountains, contain 
 no vestige cf animal or organic remains ; they 
 are, therefore, considered to be in their primitive 
 state. An approach towards these summits dis- 
 covers that the sides are covered, or, like the 
 Brocken mountain, mantled around to a very 
 great elevation, by deposites enclosing sea shells 
 and other organic remains. These are common 
 in the lower Pyrennees, vvhoae elevation does not 
 exceed six or seven thousand feet above the sea : 
 
105 
 
 according to Ulloa, however, shells have been 
 found at the height of 14,220 feet above the sea 
 on a mountain in Peru. 
 
 It is extremely difficult, it is even in most cases 
 impossible, to ascertain the internal structure of 
 large and elevated mountains : but if, on ascending 
 them, it be found that their summits are crowned 
 by certain rocks which are known never to include 
 shells or other organic remains, and ivhich have 
 never yet been found resting upon those rocks 
 which do contain them; we have a right to con- 
 clude, from analogy, that the same rock which 
 forms the summit, composes the mountain itself, 
 ascending from the base to the summit through 
 the centre ; and that the masses of rock surround- 
 ing it, even to a great elevation, were deposited 
 after the creation of the central mountain. 
 
 We may, I say, conclude this to be the case 
 from analogy, because, in certain districts of the 
 European continent, the operations of the miner 
 have occasionally disclosed the fact. In various 
 parts of Germany some mines are situated in lofty 
 mountains. For instance, in the Krivan mountain, 
 there is a gold mine, 6954 feet above the sea ; 
 and in the mountains of the Tyrol, a silver mine, 
 7512 French feet above the same level. 
 
 As we are now upon the subject of mountains, 
 it may not be amiss here to introduce a sketch, 
 exhibiting the comparative heights of some in 
 various quarters of the globe, whose names a*re 
 
106 
 
 best known to us, as most frequently occurring 
 in the usual course of our reading : it is not in- 
 tended to convey a representation of their actual 
 form (see Plate 1.) To us, who live in alow arid 
 almost level country, Skiddaw and Helvellyn are 
 objects of wonder and admiration; but when 
 these, or Ben Nevis, which is the highest moun- 
 tain in Britain, are compared with the majestic 
 elevations of the European or the American Con- 
 tinents, they sink in our estimation into mere hil- 
 locks ; and the great pyramid of Egypt, that won- 
 der of ages, which is 315 feet in height, seems as 
 nothing in point of bulk. The heights of two or 
 three remarkable cities have been added. 
 
 The highest mountain in Europe is Mont 
 Blanc, in Switzerland, which is 15,662 feet above 
 the sea ; but there are several of nearly the same 
 height. 
 
 The highest mountain in Asia is Petcha, or 
 Hamar, in Chinese Tartary, which is estimated 
 at 15,000 feet above the plains of China ; unless 
 it be admitted, that the highest summit of the 
 mountains of Thibet exceed it, which, according 
 to Colonel Crauford, is about 25,000 above the 
 sea. 
 
 In Africa, the highest mountains are supposed 
 to be those of Geesh, which are estimated at 
 15,050 feet above the sea. 
 
 Chimborazo, the highest summit of the Andes, 
 and the most elevated of the American continent, 
 is 20,282 feet above the sea; but there are four- 
 
107 
 
 teen other mountains on that continent, between 
 
 10,000 and 20,000 feet in elevation; three of 
 which are volcanoes. 
 
 Heights of Mountains, &c. 
 
 feet above the ca. 
 
 Britain . . Ingleborough, Yorkshire . . . 3000? 
 
 Ben Lomond, Scotland . . 3048 
 
 Saddleback, Westmoreland . . . 3240 
 
 HelvelJyn, Cumberland . . . 3324 
 
 Snowdon, Wales 3456 
 
 Skiddaw, Cumberland .... 3530 
 
 Schihallien, Scotland .... 3564 
 
 Ben Nevis, Scotland .... 4350 
 
 ftaly . Vesuvius 3900 
 
 France . . Puy de Dome 5000 
 
 Puy de LanfF 6200 
 
 Plomb de Cantal .... 6300 
 
 Jamaica . . Blue Mountains ..... 7431 
 
 Germany . Lomnitz Peak 8640 
 
 Kesmark Peak " 8508 
 
 Krivan 8300 
 
 Pyrennees . Canigou 9000 
 
 Mont Perdu 11,000 
 
 Canary Islands Peak of TenerifFe , 11,424 
 
 Sicily . . JEina 10,032 
 
 Alps . . . Lake Lauzon, Mont Olan . . 6796 
 
 MontTitli* . ... . . 10,818 
 
 Schrekhorne . . . . . 13,000 
 
 Mont Rosa 15,000 
 
 Mont Blanc 15,662 
 
 America . City of Mexico " 7424 
 
 City of Quito 9000 
 
 Silver Mine of Jauricocha . . . 15,500 
 Tunguragao . . . . .16,170 
 
 Cotopaxi 18,600 
 
 Ohimborazo 20,282 
 
108 
 
 We have now arrived at that branch of ow 
 subject which may be termed Mineral Geology ; 
 TV tiic a fiasfor itsotyect the natures and differences 
 existing in the component mosses oj the earth. 
 
 These masses are, by Werner, divided mio pri- 
 mitive, transition, jlwtz, and alluvial. 
 
 PRIMITIVE ROCKS never contain animal or 
 ether organic remains, and are never found to 
 alternate with, or to rest upon those rocks, which 
 enclose animal remains. 
 
 Primitive rocks are so named, because, in so far 
 as we know, they are the oldest, and were the 
 first formed. They have a crystalline appearance, 
 and are, therefore, chemical deposites, principally 
 composed of the siliceous, argillaceous,* and 
 magnesian earths. Granite, gneiss, mica-slate, 
 clay-slate, primitive limestone, serpentine, por- 
 phyry, and sienite, are of this kind. Of these, 
 granite is considered to be the oldest, and sienite 
 the newest. 
 
 To primitive rocks succeeds another class, 
 which Werner denominates TRANSITION ROCKS ; 
 these enclose organic remains of animals now in- 
 habiting the seas, and are principally composed 
 of chemical deposited ; but amongst them mechani- 
 cal deposited first make their appearance.f 
 
 * The earth called alwnine forms the basis of common alum, whence 
 it obtained that name ; it enters largely into the composition of clays, 
 whence it is termed the argillaceous earth, from the Latin argilla, clay. 
 
 f The difference between a chemical and a mechanical deposite may 
 be thus explained. 
 
109 
 
 Limestone, though it sometimes occurs among 
 primitive rocks, first appears in considerable 
 quantity among transition rocks ; amongst which 
 greywacke, greywacke-slate and transition lime- 
 stone are the predominating rocks. 
 
 Still newer than transition rocks, is the ex- 
 tensive class of FL<ETZ ROCK ; the older of these 
 contain the remains of sea fish approaching in 
 character to the kinds now found in the ocean and 
 the newer of them contain shells precisely the same 
 as now exist in the sea. Flo3tz rocks are, for the 
 most part, mechanical deposites. The principal 
 among these are limestone and sandstone ; to 
 which may be added gypsum, salt, and great ac- 
 cumulation of inflammable matter in the state of 
 coal. 
 
 A chemical deposits is th result of that law of nature which ha 
 been already explained, called affinity. 
 
 Pounded flint, which is nearly pure .'ilex, with a certain proportion of 
 potash and some other substances, when melted, forms a glass which it 
 lokihle in water. When thus dissolved, the mixture is called the liquor 
 nf fiinl*. It is said that a quantity of this liquor was left in a bottle 
 during eijrht years, by Professor Siegling ; who found that the force of 
 affuiify acting upon the particles of si lex in the iiquor, cau-ed them to 
 be dejKnited in transparent crystals! of quartz, hard enough to give fire 
 with uiie st.'ol. ThcTL- crystals were therefore a real chfmical droosite. 
 
 A mechanical dtpofile is effected without the agency of affinity. If, 
 for in. -lance, cand or day he mixed up in wa<er, it will he deposited 
 without regularity, or ii.tiir.a'e combination, merely by its own w- iaht. 
 If this deposite be le.t to d;y, and to become hard, it will not hr.-ak 
 in any PI: '.!.:'. d^ix-'ion. i;or will the particles of which it i 5 -com;io>ed 
 ad'u-re to^.-'th-r very .-tror^ly. There is no regularity, it is a mere 
 accidental or mechanical dqwxlc. 
 
 L 
 
110 
 
 Still newer is the class of ALLUVIAL ROCKS ; 
 these contain the shells of fish now existing in the 
 seas, and the bones of large land animals ; and are 
 almost entirely composed of mechanical deposites. 
 Sand, clay, loam, and brown coal, are the prin- 
 cipal earthy masses that belong to this class. 
 
 Such is the arrangement which observation has 
 taught the experienced Werner to make in rocks. 
 Some other geologists, however, are of opinion, 
 that the division made by him of rocks enclosing 
 organic remains into two classes, transition and 
 floetz, is unnecessary : they therefore term all those 
 rocks which contain organic remains, excepting 
 those called alluvial, SECONDARY ROCKS. 
 
 We'learn from what has preceded 
 1st. That the older rocks are principally com- 
 posed of the siliceous, argillaceous,* and mag- 
 nesian earths.f 
 
 2nd. That the primitive parts of the crust of the 
 earth are entirely chemical productions; where- 
 as, in the newer, we find a beginning, and in 
 the still newer, an increasing quantity of me- 
 chanical depositions. 
 
 3d. That limestone occurs but sparingly in the 
 primitive, more abundantly in the transition 
 (or older secondary.) and in the flcetz class (or 
 newer secondary) in immense quantity. 
 
 * See last note but one. 
 
 f See notes to the descriptions of the nine oldest and most abundant 
 f the primitive rocks. 
 
Ill 
 
 4th. That in the earlier deposites we meet with 
 no bituminous or saline matters, as coal or 
 slate, but that these occur in great quantity 
 in the newer formations. 
 
 But that part of our subject to which we are 
 now arrived, viz. the consideration of the nature 
 of the individual rods or compound masses, which 
 been bought to light by the operations of 
 the miner, or the researches of the geologist, 
 opens to us a field of inquiry of such amazing 
 extent, as to induce me to pause, and, for a mo- 
 ment, -to consider the precise nature of the ob- 
 ject we have in view. 
 
 This, if I rightly understand it, seems to be the 
 acquisition of such knowledge of the great outline 
 of geological facts andphenomena, as the researches 
 of men eminent in science have enabled us to 
 attain ; avoiding, on the one hand, an attempt to 
 enter with mineralogical exactness into the study 
 of every geological compound, and on the other, 
 the bare recital of a catalogue of geological 
 names ; neither of which would afford either in- 
 terest or instruction. 
 
 In the consideration of the natures of individual 
 rocks, are involved the remainder of our geologi- 
 cal positions. We proceed to the 
 
 13th. That rocks which, because they con- 
 clude no vestige of animal remains, are termed 
 primitive, are of various kinds. 
 
 14th. That rocks enclosing animal remains 
 are never found underneath, or supporting, 
 those rocks which are termed primitive. 
 
112 
 
 15th. That some primitive rocks alternate 
 with each other ; but that granite is found be- 
 neath all others, and frequently overtops all 
 the rest. 
 
 16th. That rocks which include organic re- 
 mains must have been formed after the shells 
 they contain, and, therefure,noi bt in<$ considered 
 primitive^ are, by some, termed secondary rocks: 
 whence the terms used by geologists of 'primary 
 and secondary formations. 
 
 17th. That there are many varieties of se- 
 condary rocks, each of which has received a 
 geological appellation. 
 
 1 8th. That there exists another class of sub- 
 stances, not appropriately termed rocks, but 
 which, being considered to be the debris, or 
 ruin of rocks, by their long exposure to the 
 action of air or water, or both, are therefore 
 termed alluvial deposites. 
 I shall now invite your attention to that clas- 
 sification of rocks which the experience and ob- 
 servations of Werner have induced him to make. 
 
 PRIMITIVE ROCKS. 
 
 Granite Porphyry 
 
 Gneiss Sienite 
 
 Micaceous schistus Topaz rock 
 
 Argillaceous schistus -Quartz rock 
 
 Primitive limestone Primitive flinty slatt 
 
 Primitive trap Primitive gypsum 
 
 Serpentine White stone 
 
113 
 
 SECONDARY ROCKS ; 
 
 or 
 TRANSITION ROCKS. FIXETZ ROCKS. 
 
 Transition limestone Old red sandstone 
 Transition trap Floetz limestone 
 
 Greywacke Floetz gypsum 
 
 Transition flinty slate Variegated sandstone 
 
 Second floetz gypsum 
 
 Shell limestone 
 
 Third sandstone 
 
 Rock salt 
 
 Chalk 
 
 Flostz trap 
 
 Coal 
 
 Newest floetz trap 
 
 ALLUVIAL DEPOSITES. 
 Sand, gravel, loam, clay, wood-coal, &c. 
 
 But before we proceed to examine these rocks 
 individually, let us take some further notice of 
 the interesting section of the Brocken Mountain, 
 which throws much light on the subject of the 
 relative situation of mountain masses in general. 
 An outline of the nature of these masses will of 
 course be comprehended in the succeeding de- 
 scription of individual rocks. The centre of the 
 mountain is granite, (1,) on each side reposes 
 another primitive rock, called clay slate, (2.) which, 
 as well as all the succeeding strata, is found entire- 
 ly to surround the granite. The two strata 
 L 2 
 
114 
 
 next in succession (3, 4,) are by Werner termed 
 transition rocks; the first being limestone, the next 
 greywacke and greywacke-slate. The stratum 
 resting on the latter is called by Werner, the old 
 red sandstone, (5,) and is the oldest of what he 
 terms the flcctz rocks ; the succeeding strata to 
 (10,) inclusive, are also floetz rocks. On the old 
 red sandstone reposes the Istflxtz limestone (6) ; on 
 it the \stflatz gypsum (7) ; then succeeds the 2d 
 or variegated sandstone (8) ; then the 2cl or newer 
 gypsum (9) ; and lastly, the 2d limestone (10). It 
 is essential to be noticed, that I do not pretend to 
 give the precise extent, dimension, OF shape, of 
 the granite forming the centre of this mountain, 
 or of the several successive and incumbent strata; 
 their general shape and position is all that is in- 
 tended to be conveyed. Nor must we forget to 
 observe that, in reality, all the strata incumbent 
 on the granite, are less and less in elevation as 
 they are more and more distant from it, each 
 newer deposite being lower than that preceding 
 it in point of age and situation. Nor must we 
 fail to remark that these several strata, which 
 may be supposed to stretch along through a con- 
 siderable tract of country, would soon assume that 
 position which determined Werner to give to the 
 newer amongst them the term of floetz rocks; that 
 is to say, they would be .fiat, which is the meaning 
 of the word floetz. On the 2d limestone (10) re- 
 poses the alluvial deposite (11) j with the precise 
 nature and extent of this 1 am not acquainted. 
 This section has so greatly the appearance of 
 
115 
 
 order and of art, that it might be supposed to be 
 the mere contrivance of some theorist to answer 
 the particular objects of his invention : but we 
 have no reason to suspect it. That Werner is in 
 some sort a theorist, perhaps, can scarcely be de- 
 nied ; but it must, at the same time, be allowed, 
 that his great object has been to develope a grand 
 outline of the facts presented by nature, and that 
 his theory is wholly built upon investigations, to 
 which the great mining and mountainous district 
 in which he resides is particularly favourable. A 
 Cornish miner of observation and talent, but 
 whose education and knowledge is principally 
 confined 4o his art; who had never read, or per- 
 haps even heard of a theory of the earth, lately 
 told me that on examining a certain district in 
 Wales, he was surprised to find on the side of a 
 mountain, strata of various kinds in regular suc- 
 cession, and much more so to observe the same 
 strata in the same order on the side of another 
 mountain distant nearly 20 miles from the former. 
 It was the more remarkable to him, because 
 Cornwall is not a stratified country. 
 
 I have selected for your inspection the section 
 of the Brocken mountain, as being a well au- 
 thenticated example of remarkable order in its 
 several deposites, and because the relative position 
 of rocks, and the order in which they succeed or 
 cover eat h other, forms a curious and interesting 
 part o 1 ' geological inquiry. If, however, we were 
 to imagine that this forms a representation 
 
116 
 
 deposites of mountain masses in the aggregate, 
 we should err. Though granite frequently over- 
 tops other rocks, it is, perhaps, more frequently 
 found, that other primitive rocks rest immediately 
 upon and above it. Granite is sometimes ob- 
 served to alternate with gneiss, and gneiss with 
 micaceous schistus and clay-slate. 
 
 Mont Blanc, which is 15,680 feet high, and is 
 the highest mountain in Europe, is of granite 
 nearly to the summit ; which is, according to Saus- 
 sure, of argillaceous schistus. It is said that in 
 the Andes, in South America, granite has not 
 been seen higher than 11,500 feet above the sea. 
 A mountain called Marno, in Portugal, is granite 
 covered by clay-slate enclosing crystals of a mi- 
 neral called the chiastolite. The same rock en- 
 closing the same substance, forms the summit of 
 Skiddaw in Cumberland, probably resting also on 
 granite. 
 
 It is sometimes found that several of the primi- 
 tive rocks rest upon the granite, and above these 
 some of the transition or floetz rocks ; or, as they 
 have been conjointly termed by some geologists, 
 secondary rocks. Even alluvial matter is said to 
 have been observed, covering the summits of ele- 
 vated mountains. 
 
 But it has been objected to the rules laid down 
 by Werner, in regard to the relative ages and 
 positions of rocks, as forming mountain masses, 
 that, as his observations have been chiefly confined 
 to the country in which he resides, it is not rea- 
 
117 
 
 sonable to adopt the result of researches with 
 regard to one district, as obtaining in every other 
 country. This objection may, in srrr.e degree, he 
 well founded. The observations of other geolo- 
 gists in other countries may not be all in perfect 
 accordance with the rules laid down by Werner: 
 but this dissonance may be attributed in some 
 measure to the yet imperfect state of the science, 
 and to the want of precise definitions in regard to 
 the characters of many rocks. Some, which have 
 obtained the same appellations, are so different 
 in appearance, that the most experienced eye 
 alone can determine their general agreement in 
 regard to character and composition ; while, on 
 the other hand, certain others have obtained dif- 
 ferent names in different countries. In this im- 
 perfect state of geological language, the know- 
 ledge and skill of the observer must always be 
 had in consideration. 
 
 If Werner be actually a theorist, he is one of a 
 superior order. He has extended his researches 
 throughout the large and important district sur- 
 rounding him. The relative age, deduced from 
 the relative position, internal structure and con- 
 tents of the great masses forming that moun- 
 tainous district, seems to have been ascertained 
 by him with a degree of certainty that defies the 
 application of the term theory to his results. If 
 he merit the name of theorist at all, it seems only 
 to be in consequence of his assertion, or supposed 
 assertion, (for hitherto his principal discoveries 
 
118 
 
 have been communicated only by some of his pu- 
 pils) that the same results will.be found to prevail 
 universally. It is certain that researches in al- 
 most every quarter of the globe, have tended in 
 an astonishing degree to verify his opinions, that 
 order in regard to deposition is universally pre- 
 valent, and that this order is never inverted. 
 
 It cannot, however, be denied, that theories built 
 even upon researches into the phenomena pre- 
 sented by nature, have both advantages and dis- 
 advantages. They serve to induce research, in- 
 quiry, and discussion ; which, when carried on 
 with that temperate zeal which may be expected 
 from men whose object is truth, will be sure to 
 promote it. It were to be wished that the love 
 of truth were thus prevalent ; much needless and 
 intemperate warmth would be averted ; and were 
 observers bent on this alone, as their ultimate 
 object, science would be benefited by nicer 
 ancj more candid geological description than can 
 be expected from those, whose great object is the 
 support of a favourite theory. 
 
 Inquiries into the nature of the globe contribute 
 greatly to the advance of real science ; they serve 
 at once to amuse and to instruct, by affording 
 ample materials for reflection ; they force upon the 
 mind an immovable conviction that the globe it- 
 self was called into existence by a Power, whose 
 design and contrivance are every where manifest : 
 a power whose immensity is unsearchable. 
 
119 
 
 The few rocks that have been mentioned as 
 composing the principal masses of primitive, tran- 
 sition, and flcetz, or seconder rocks, and of allu- 
 vial deposites, comprehend, as it were, within 
 their catalogue, and connected with their history, 
 a variety of other rocks so vast and so numerous, 
 and passing'l4ie one into the other by such imper- 
 ceptible and nice gradations, that it may truly be 
 said their study is the business of a life. 
 
 I now proceed to offer some remarks on the 
 nature of individual rocks ; beginning with the 
 oldest of the primitive rocks, and taking occasion 
 to notice some of their masses, remarkable for 
 extent and elevation, as well as the metalliferous 
 ores which principally abound in them. 
 
 GRANITE is a compound, granular, aggregated 
 rock, composed of felspar, quartz, and mica, most- 
 ly in distinct crystals; sometimes the one, some- 
 times the other of these ingredients predominates, 
 but most generally the felspar.* 
 
 But granite varies in respect to its granular 
 character, from the very large to the very small ; 
 the large granular is considered to belong to the 
 
 * Quartz, felspar, and mica, enter into the composition of granite 
 and gneiss, the two oldest of the primitive rocks. Quartz is composed of 
 eilex, with 2 or 3 per cent, of moisture or water. Felspar, of about 
 63 parts of silex, 17 of alumine, 3 of liine, 13 of potash, and 1 of 
 oxide of iron. Mica, of about 47 parts of silex, 20 of alumiue, 13 of 
 potash, 15 of oxide of iron, and 2 of oxide of manganese. 
 
120 
 
 oldest formations, the small and fine grained gra- 
 nite to the newest. 
 
 Werner considers that there are three sorts of 
 granite : the primitive ; a newer formation which 
 traverses the primitive in veins, and the newest 
 granite formation ; this latter always rests on 
 some of the older primitive rocks. It sometimes 
 contains portions of other rocks. 
 
 The colour of granite is grayish white or red- 
 dish. 
 
 Granite sometimes contains other substances, 
 as schorl, garnets, and tin ore : many metalliferous 
 substances are found in veins that traverse it. 
 
 In the great mining field of Cornwall, both 
 copper and tin occur in veins in granite in prodi- 
 gious quantities. 
 
 When granite is exposed, it forms very high 
 and steep cliffs ; often also it appears as lofty and 
 precipitous summits, denominated peaks ; as is 
 remarkably the case in Savoy, in Switzerland. 
 
 It occurs, as forming mountain masses, both 
 un'stratified and stratified ; when in the former 
 state, it presents large irregularly shaped masses, 
 sometimes distinct globular concretions, as in 
 Bohemia, the Hartz, arid other places. Strati- 
 fied granite occurs in Bohemia, Saxony, Switzer- 
 land, the Pyrennees, the Altain opouptfeina, and in 
 other countries. According to Jansrson, ' S'nita 
 can only be formed by parallel seams., ^ >h have 
 the same direction and extent throughout the 
 mass.' 
 
121 
 
 Granite is one of the most frequent and widely 
 extended rocks : it forms the summits of the 
 highest mountains in Scotland, in the Hartz, the 
 Alps, in Bavaria, Bohemia, the Tyrol, and most 
 countries in Europe. It forms a very consider- 
 able portion of the Uralian and Altain chain of 
 mountains in-Siberia in Asia. In Africa, it forms 
 the principal constituent part of the mountains of 
 Upper Egypt, the Atlas mountains, and of the 
 country about the Cape of Good Hope. In North 
 America, it is found in New- York, Pennsylvania, 
 and Virginia. In South America, it forms whole 
 groups of the elevated Cordilleras ; and a large 
 tract of country extending from Cape Horn,which 
 is the southern extremity of America.' 
 
 It is remarkable, that in the mountainous re- 
 gions of Peru, especially in the environs of vol- 
 canoes, no granite is found except in low situa- 
 tions, at the bottoms of valleys. 
 
 GNEISS is the next oldest of the primitive rocks, 
 and like granite, it consists of felspar, quartz, and 
 mica; it is generally so small-grained, and the 
 mica for the most part prevails so much, that 
 gneiss is mostly of a slaty structure. 
 
 It sometimes encloses other rocks, a? granular 
 limestone and porphyry. It contains occasion- 
 ally beds of garnet, accompanied by lead ore and 
 iron pyrites; and sometimes, though rarely, beds 
 of slaty glance coal. 
 
 Mountains composed of gneiss are not so stetp 
 M 
 
122 
 
 as those composed of granite ; their summits are 
 usually rounded. 
 
 There are few metals that do not occur in 
 gneiss ; in which are situated the greatest part of 
 the Saxon, Bohemian, and Salzburgian mines. 
 
 Gneiss mostly reposes on granite, but is some- 
 times incorporated in it, and sometimes alternates 
 with it. 
 
 Ben Lomond, in Scotland, and Mount Rosa, in 
 Italy, are almost wholly composed of gneiss, as 
 well as the middle part of the Pyrennees. It 
 abounds in Bohemia and Silesia, in Carinthia, in 
 the Southern Alps, the Vosges, and in Scandina- 
 via. It occurs also in Greece ; the mine works of 
 the ancients, in the vicinity of Athens, are situated 
 in it ; it is found also in Russia, in several dis- 
 tricts of South America, in the Shetland Islands, 
 and in many parts of the main land of Scotland. 
 
 MICACEOUS SCHISTUS is considered to be the 
 next oldest of the primitive rocks. This is also 
 called schistose mica, mica-slate, and glimmer- 
 schieffer. This rock is composed of mica and 
 quartz,* and like gneiss, has a slaty structure. 
 Garnets are so commonly found in it, as to be 
 almost considered one of its constituent parts : 
 occasionally it contains several other substances. 
 
 Micaceous schistus usually rests on gneiss, but 
 is not commonly found on the summits of moun- 
 tains ; nor does it often alternate with granite or 
 
 * For the analyiis of mica and quart*, see note oa granit*. 
 
123 
 
 gneiss ; but generally reposes on the latter, round 
 the sides of the primitive mountains, forming 
 gentle acclivities. The summit of hills composed 
 of micaceous schistus are round. 
 
 It contains some ores, as gold, iron, copper 
 pyrites, arid cobalt, with garnets and asbestus ; 
 but unlike gneiss, in which they occur in veins, it 
 contains theln in beds. 
 
 The most important mines of Sweden, as those 
 of Dalecarlia and Fahlun ; those of Roraas, in 
 Norway ; many in Hungary, Salzburg, Saxony, 
 and Bohemia, are situated in micaceous schistus. 
 
 It is found in many parts of Scotland ; the 
 mountain Schihallien and the neighbouring coun- 
 try, are composed of it. Humboldt observed it 
 in great quantities in South America. 
 
 ARGILLACEOUS SCHISTUS, or CLAY-SLATE, is 
 a simple mountain rock,* and follows micaceous 
 schistus in the great series of mountain rocks ; 
 but it sometimes contains thin layers of quartz, 
 or more rarely of felspar. It also contains some 
 other mineral substances, as schorl, garnet, 
 and hornblende ; and sometimes encloses other 
 rocks. 
 
 Geologists enumerate four varieties of this rock, 
 
 * The three foraier rocks are called compound mountain rocks, be 
 ing composed of two or three mineral substances, viz. quartz, felspar, 
 and mien ; but argillaceous schistus is called a simple mountain rok, 
 because it is not so compounded. It consists of two or three elementary 
 substances, as of silex, alumine, and oxide of iron. There are several 
 varieties of this rock, which have not been accurately analysed. 
 
124 
 
 one of which is of roofing slate; and eight varieties 
 of rock peculiar to the clay-slate formation; 
 amongst which is drawing slate. The impossi- 
 bility of noticing all these varieties will be obvious, 
 nor does it form a part of our present object. 
 
 Argillaceous schistus is one of the most metalli- 
 ferous of the primitive rocks ; it abundantly con- 
 tains veins and beds of tin, lead, cobalt, silver, and 
 copper; gold, and the ore of quicksilver are said 
 also to occur in it. It is a very widely extended 
 rock, and sometimes forms whole mountains and 
 chains of mountains; but not of the most elevated: 
 they have generally a gentle acclivity. 
 
 In the Highlands of Scotland, argillaceous 
 schistus rests upon, and passes into, micaceous 
 schistus. On the continent of Europe, it may be 
 traced through a great extent of country ; as in 
 Saxony, Bohemia, Silesia, Franconia, Bavaria, 
 the Alps of Switzerland, Austria, Hungary, and 
 many other districts. It occurs in Pennsylvania 
 in North America. It is said that nearly the 
 whole country between Potosi and Lima, in South 
 America, is composed of it. 
 
 Saussure found it on the summit of Mont Blanc. 
 In Britain, it occurs largely in Cornwall, enclosing 
 veins of tin and copper ; and it forms the summit 
 of Skiddaw, in Cumberland. The famous moun- 
 tain of Potosi, in which are situated the great 
 silver mines, consist entirely of clay-slate. 
 
 - PRIMITIVE LIMESTONE is the next in order of 
 
125 
 
 primitive rocks. It is a simple mountain rock,* 
 and is white, yellowish, grayish, greenish, or red- 
 dish white. It structure is always granular. The 
 oldest is the whitest and most granular. 
 
 It sometimes encloses quartz and mica ; more 
 rarely garnets, steatites, asbestus, and some other 
 mineral substances. 
 
 Occasionally it occurs in distinct strata 5 or in 
 beds, sometimes short and thick, sometimes so 
 thick as to form whole mountains. 
 
 Primitive limestone is rarely found enclosed in 
 the older rocks called gneiss and clay-slate, just 
 described. As a rock, it contains various mineral 
 ores in beds and veins; as those of lead, zinc, and 
 iron, auriferous pyrites, and native gold. 
 
 Whole mountains in Stiria, Carinthia, Carnio- 
 lia, and in the Pyrennees, are composed of it ; 
 as well as three in Switzerland 30,000 feet high. 
 But primitive limestone in these situations, is 
 generally in immense blocks, without any regu- 
 larity in regard to size, dip, or direction ; it is 
 sometimes stratified, as at Altenburg, near the 
 lake Neuenburg, and in some parts of Scotland. 
 
 * When lime is combined with the carbonic acid, the compound, 
 when compact, is commonly called limestone ; another variety is called 
 calcareous spar, (calx being the Latin for lime,) and mountains of lime- 
 stone r.re commonly called calcareous mountains. 
 
 Calcareous spar ia composed of 57 parts of lime, nnd 43 of carbonic 
 acid. Th limestone of calcareous mountains yieldi about the ?amt 
 proportion?. 
 
 M2 
 
126 
 
 The marble of Sutherland, in Scotland, is said 
 to be particularly valuable. The promontory of 
 Athos, in the Archipelago, is composed of primi- 
 tive limestone ; but the most extraordinary mass 
 of it occurs in Spain : it is said that the moun- 
 tain of Filabres consists of one block of white 
 granular marble, 2000 feet high, and 3 miles 
 in circumference, without any mixture of other 
 earths or stones, and almost without a fissure. 
 
 PRIMITIVE TRAP : the rocks belonging to this 
 formation are numerous ; they are found in Scot- 
 land and Germany abundantly, and in some parts 
 of Britain. Trap is a German word, signifying 
 a stair. The rocks of this formation are termed 
 trap rocks, because their exposure to the elements 
 causes them to take the form of steps or stairs : 
 they are very numerous ; and, on that account, are 
 less intelligible than most other primitive rocks. 
 
 Primitive trap is almost wholly composed of 
 hornblende ; which, in some varieties, is mingled 
 with felspar, in others, with mica.* 
 
 When hornblende is mixed with felspar, it 
 sometimes contains scales of mica, and is then 
 called greenstone-slate; which occurs in great 
 beds and mountain masses, and in Sweden forms 
 
 * Hornblende is a mineral which occurs massive occasionally, but 
 iiiostly in crystals confusedly intersecting each other : its colour is dark 
 green, approaching to black. It is composed of 42 parts of silex, 11 of 
 lime, 12 of alumine, 32 of oxide of iron, and some water. 
 
 For the analysis of the occasional ingredients in primitive trap, fel- 
 spar, and mica, see note on granite. 
 
127 
 
 ranges of hills, Primitive trap is very metalli- 
 ferous ; celebrated mining districts in Sweden, 
 Saxony, and Silesia, are situated in it. 
 
 SERPENTINE is considered the next in order of 
 the primitive rocks : it is a simple mountain rock.^ 
 
 Serpentine sometimes encloses other substances ; 
 and among them are asbestus, mica, and crystals 
 of quartz and hornblende. But only one instance 
 is known in which it is incidentally mingled in 
 another rock : serpentine with limestone forms the 
 precious stone denominated rerd antique. 
 
 There appear to have been two or three forma- 
 tions of serpentine. Its first appearance is occa- 
 sionally in gneiss, the oldest of rocks except 
 granite, and afterwards in micaceous schistus. 
 It never occurs in very distinct strata ; but gene- 
 rally in shapeless masses and beds. 
 
 The ores of lead, silver, and copper, are found 
 in serpentine, though not abundantly. 
 
 Serpentine rarely forms mountains, but is said 
 to form the summit of Mont Rosa, which is prin- 
 cipally of gneiss. In beds, it occurs in Silesia, 
 Bohemia, Saxony, and in the Scottish islands; 
 and it forms a large tract -of country in Cornwall, 
 of many miles in extent, in which occur veins of 
 native copper, and some veins of the soap-stone, 
 so abundantly used in potteries, which is some- 
 times accompanied by asbestus. 
 
 * Serpentine ii composed of about 45 parts of silex, 30 of magnesia, 
 15 of alumine, with icrne oxide of iron, aod water. J 
 
128 
 
 Some varieties of serpentine are exceedingly 
 beautiful, and are turned to purposes of ornament. 
 At Zoblitz, in Upper Saxony, several hundred 
 persons are employed in quarrying, cutting, turn- 
 ing, and polishing the serpentine found in that 
 neighbourhood; and the various articles into 
 which it is made are carried all over Germany. 
 
 PORPHYRY is the next in age of primitive 
 rocks, and is one of the most widely extended 
 formations. 
 
 It is a compound rock, consisting of crystals of 
 quartz or felspar, or both, imbedded in a basis 
 which is considered to be of contemporaneous 
 formation : this basis, in the older porphyries, is 
 generally of hornstone or compact felspar : in the 
 newer formations, the imbedding substance is ge- 
 nerally of various kinds of clay.* Occasionally, 
 porphyries contain portions of clay and agate, or 
 chalcedony, and some other substances. 
 
 Porphyry sometimes contains the ores of gold, 
 silver, lead, tin, iron, copper, and manganese ; but 
 these occur principally in the newer porphyries ; 
 always in veins, never in beds. The principal 
 mines of Hungary are situated in porphyry. 
 
 Porphvry does not appear in distinct and well 
 defined strata ; but occurs in beds of great magni- 
 
 * For the analysis of the imbedded substances of porphyry, quartz, and 
 felspar, see note on granite. It is difficult to give that of the imbedding 
 substances which are numerous. It will suffice to say that they are pri- 
 cipally composed of the siliceous and argillaceous earths. 
 
129 
 
 tude, sometimes indeed forming mountain masses 
 in -various parts of the world. 
 
 It is found occasionally in Scotland and the 
 Scottish isles. On the continent, it may be traced 
 from Norway to the borders of the Black Sea. 
 It appears in Sweden, Finland, the Hartz Forest, 
 Saxony, Bohemia, Silesia, Salzburg, the Tyrol, 
 Carinthia, Carniola, Greece, the islands of the 
 Archipelago, Egypt, Siberia, and in North and 
 South America. 
 
 SfENiTE is the next oldest of the primitive 
 rocks; it is less abundant than most, if not all, of 
 the foregoing. 
 
 It is compound, and consists of hornblende 
 and felspar ; the felspar predominates : some va- 
 rieties contain quartz and mica, and but little 
 hornblende.* Sicnite is very nearly allied to por- 
 phyry, and is equally metalliferous. 
 
 In the island of Cyprus it affords much copper ; 
 many of the important silver and gold mines of 
 Hungary are situated in it. 
 
 Sienite occurs in Galloway, in Scotland : on the 
 Continent, in the Electorate of Saxony, the forest 
 of Thuringia, (where it abounds in iron,) Upper 
 and Lower Hungary, Transylvania, the Isle of 
 Cyprus, arid Upper Egypt. 
 
 * For the analysis of hornblende, see note on primitive trap : and for 
 tiue analysis of fefcjxir, quartz, and mica, see that on granite. 
 
130 
 
 According to Werner, there are yet five other 
 primitive rocks, making in the whole fourteen : 
 these are of far less abundant occurrence than the 
 foregoing, and will not detain us long. 
 
 ^TOPAZ ROCK is composed of quartz, topaz, 
 schorl, and a sort of clay : it is rare, having 
 hitherto only been found near Auerbach, in Ger- 
 many, where it forms a mountain mass of con- 
 siderable extent. 
 
 QUARTZ ROCK is a simple mountain rock, oc- 
 curring principally in veins and beds ; but en- 
 closing no metallic ores of any description. Some- 
 times it includes mica, and has then a slaty texture. 
 Quartz occurs plentifully in certain mountains in 
 Scotland, and in some of the Scottish isles. On 
 the Continent, it appears in Saxony, Bohemia, 
 Silesia, Bavaria, and other places. It is, however, 
 said, that the mountain called Bultuc, one of the 
 Altain chain, in Siberia, being 350 feet high, and 
 4800 broad and long, consists entirely of milk- 
 white quartz ; which sometimes forms spires on 
 the tops of mountains, appearing like snow. 
 
 PRIMITIVE FLINTY SLATE occurs occasion- 
 ally in beds, in some of the German and Saxon 
 mountains, alternating in beds with clay-slate be- 
 fore described: it occurs also in veins. But this 
 rock is scarcely known beyond those districts. 
 
 PRIMITIVE GYPSUM is perhaps the least im- 
 portant of all primitive rocks. It has hitherto 
 been found only in the Alps in Switzerland, where 
 it is granular 5 but, being mixed with mica and 
 
331 
 
 clay-slate, the rock obtains a slaty structure : this 
 structure is never to be observed in secondary 
 gypsum, and therefore serves as a complete dis- 
 tinctive character. 
 
 WHITE STONE : the characteristic colour of this 
 rock is white ; it is composed of a little mica and 
 compact felspar, and has a slaty or granular 
 structure : sometimes it contains garnets. Hither- 
 to it has been principally found in Saxony and 
 Moravia : a variety of it appears in the mountains 
 of the South of Scotland. 
 
 We have now taken a cursory view of what, 
 according to our present knowledge of the crust 
 of the globe, are considered to be the oldest rocks. 
 All these, though some of them be occasionally 
 found mingled, or alternating in beds or strata 
 with each other, are crystalline deposites, and are 
 absolutely without any trace of organic remains, 
 either of plants or animals : for this reason, these 
 are supposed to be in the very state in which they 
 were first deposited, and therefore have received 
 the name of primitive rocks. 
 
 But the fourteen rocks of which we have taken 
 a slight view, are not, by some geologists, supposed 
 to form the whole catalogue of primitive rocks ; 
 jasper, hornstone, pitchstone, hornblende-slate, 
 and puddingstone, are, by some, added to it : some 
 of these appear to be varieties of those we have 
 described, and the characters of the rest^do not 
 seem to be so essentially fixed, as forming moun- 
 
132 
 
 tain masses, as to induce me to detain you by 
 their description. 
 
 All rocks not included in the foregoing cata- 
 logue, (with the exception of those called alluvial,) 
 have, hy some geologists, been termed secondary, 
 because they are found to contain more or less of 
 organic remains : but it has been discovered that 
 the four rocks found in immediate succession to 
 the preceding fourteen, do not contain organic 
 remains precisely of the same characters as the 
 rest. For although the four rocks in question en- 
 close some shells common to those immediately 
 in succession to them, they also contain a variety 
 of petrifactions, distinct in their characters, called 
 zoophites, or those animals which are considered 
 as forming the first link in the chain of animated 
 beings; none of which are found in any of the 
 succeeding rocks. 
 
 In these four rocks, which contain ihe first traces 
 of organic remains, also appear the first mechani- 
 cal deposites; and Werner has termed them tran- 
 sition rocks, as connecting the primitive with the 
 newer rocks containing abundance of the remains 
 of plants and animals ; these newer rocks he has 
 called jflffts rocks, (the word Jiatz, meaning fat,) 
 because the position in which they are found is 
 more flat than that of the primitive or transition 
 rocks ; and is frequently quite flat. 
 
 It has already been remarked that some geolo- 
 gists, who are of opinion that some of the dis- 
 tinctions made by Werner are not necessary, class 
 
133 
 
 all those be has named transition and flcetz, under 
 the general term of secondary rocks. 
 
 The four transition rocks are called transition 
 limestone, transition trap, greywacke, and tran- 
 sition flinty slate. 
 
 TRANSITION LIMESTONE does not rise so high 
 on the sides of mountains as primitive rocks ; but 
 it occurs in mountain masses, forming precipices, 
 and narrow and deep vallies. It is not very 
 metalliferous. 
 
 In beds, it occurs in Scotland, and in Derby- 
 shire ; on the Continent, in the Hartz Forest, and 
 most other mining districts. 
 
 Of TRANSITION TRAP there are two varieties; 
 one of them called amygdaloid, or, in Derbyshire, 
 toadstene, forms immense beds with transition 
 limestone in that county : it is found also in the 
 mining districts in Germany. 
 
 GREYWACKE is a widely distributed and im- 
 portant rock ; it presents the first appearance of 
 a mechanical deposite. 
 
 It is described by Jameson as composed of 
 grains of sand, connected together by a basis of 
 clay slate. 
 
 Greywacke is uncommonly productive of metal- 
 liferous ores, both in beds and veins. Almost all 
 the mines in the Hartz are situated in it, affording 
 silver, copper, zinc, and lead. In Transylvania, 
 greywacke is traversed by numerous small veins 
 
 of gold. * 
 
 N 
 
134 
 
 This rock is also found in most European 
 countries. 
 
 TRANSITION FLINTY SLATE is of small im- 
 portance ; it principally occurs in Bohemia, and 
 in the lead hills in Scotland. 
 
 To the four transition rocks just described, 
 succeed the floetz rocks, which are twelve in 
 number, according to Werner. It has just now 
 been observed that the whole sixteen are fre- 
 quently, if not commonly, denominated seconda- 
 ry rocks. 
 
 As the position of the floetz rocks is mostly flat, 
 we may correctly imagine them to exist as twelve 
 beds, deposited one above another : and as they all 
 contain animal or vegetable remains, I do not 
 propose to give a minute description of each, but 
 shall content myself with saying that they are 
 found in most countries; in many, in prodigious 
 quantities. Generally speaking, they contain few 
 metalliferous substances ; nevertheless some of 
 them are of almost infinite value to man. 
 
 The first or oldest of these is called the OLD 
 RED SANDSTONE, which, in point of age, succeeds 
 the transition rocks just described. 
 
 On the red sandstone reposes the FIRST FLCETZ 
 LIMESTONE ; which, in the Hartz Forest, yields 
 copper and cobalt in veins. 
 
 On the first floetz limestone lies the FIHST 
 FLOSTZ GYPSUM ; containing, in Italy, and on the 
 banks of the Wolga, masses of sulphur of several 
 hundred weight. 
 
135 
 
 On the first gypsum, rests the SECOND, or VA- 
 RIEGATKD SANDSTONE; so called from its being 
 marked with brown, red, and white stripes. 
 
 On the variegated sandstone lies the SECOND or 
 FLCETZ GYPSUM ; and on this, the SECOND or 
 SHELL LIMESTONE ; remarkable for the immense 
 quantity, as well as beauty and variety of organic 
 remains, both of animals and plants, endued in 
 it in various countries of Europe. 
 
 On the shelly limestone rest* the THIRD S .-, - 
 STONE, remarkable in Bohemia for the pictun 
 scenery afforded by the numberless pillar;: 
 pyramids, single or joined together, two or three 
 hundred feet high, over a large tract of country 
 at Auerbach : in the neighbourhood also, caverns 
 and grottos appear in the same sandstone, from 
 which issue, streams, that give rise to water-falls, 
 and thus increase the beauty of the scene. 
 
 On this, which is the third floetz sandstone, 
 rests the ROCK SALT FORMATION. Of this ex- 
 tensive and highly beneficial deposite, it is my in- 
 tention to give a somewhat detailed recount, 
 particularly of our vast deposite in Cheshire. 
 
 To the rock salt formation, according to Wer- 
 ner, succeeds the CHALK FORMATION; the earth" 
 iness of which denotes the lateness of its origin. 
 To the chalk succeeds that which is called the 
 FL(ETZ TRAP FORMATION; and over it the IN- 
 DEPENDENT COAL FORMATION. As a descrip- 
 tion of some coal districts, particularly our own, 
 would now occupy too much time, I purpose on a 
 
136 
 
 future evening to give some account of this valu- 
 able deposite. 
 
 To the coal succeeds that which is by Werner 
 termed the NEWEST FLCETZ TRAP FORMATION; 
 which is considered by many geologists to be en- 
 tirely of volcanic origin. 
 
 These are the twelve formations, which, accord- 
 ing to Werner, succeed each other in the order 
 just described. By this we are not to suppose 
 that we shall, in every place in which one of them 
 is found, invariably find the rest : frequently many 
 of them are wanting. In the sketch of the Broc- 
 ken mountain, it will be noticed that the two pri- 
 mitive rocks, gneiss and micaceous schistus, are 
 wanting. All, therefore, that we mean to say, in 
 pointing out their successive formations, is. that 
 if gneiss and micaceous schistus had occurred, 
 they would have been situated between the gra- 
 nite and the limestone. So with the floclz rocks : 
 if, for instance, we arrived at a bed of rock salt, 
 we might possibly find it resting 1 on a bed of the 
 old red sandstone, although no fewer than six beds 
 have just been described as newer than the old 
 red sandstone, and older than the rock salt : but 
 had these six beds occurred, they would have 
 been found between them ; and most probably 
 in the order laid down. 
 
 But there is still another species of deposite of 
 which wehaveto speak, improperly classed among 
 rocks, -which is invariably found above all other 
 strata. I allude to ALLUVIAL DEPOSITES. 
 
137 
 
 This class includes those substances that have 
 been formed, and still are forming, in every quar- 
 ter of the globe from previously existing rocks, 
 owing to the action of air and water upon them. 
 Alluvial deposites occur both in high and moun- 
 tainous regions, and in flat country ; filling up 
 hollows in one, and forming plains in the other. 
 
 In mountainous countries they consist of rolled 
 masses, principally of gravel or sand ; sometimes 
 irregularly heaped, sometimes forming beds, and 
 containing fragments of ores, and some kinds of 
 precious stones. 
 
 The disintegration of the surfaces of hills in 
 some parts of Cornwall, affords an extensive illus- 
 tration of the effects ascribed to the agency of air 
 and water. Large deposites of tin ore, covered 
 by the ruin of granite, are found in many places ; 
 and have afforded rich harvests to the miner. 
 In one of the branches of Falmouth Harbour, the 
 miner, after damming out the water, sunk through 
 a bed of alluvial matter fifty feet in thickness ; at 
 the bottom of which was found a bed of rounded 
 masses of tin ore, varying from two to ten feet in 
 thickness ; in which occasionally were mingled 
 small grains of gold. It may be conceived that 
 the ruin must have been great, when it is known 
 that the profits reaped from the undertaking, 
 amounted to at least 50,000. At the bottom 
 was the solid rock, on which I have walked. 
 
 The diamond is found in alluvial soil in the 
 N 2 
 
13S 
 
 East Indies and South America, as well as the 
 topaz and the hyacinth ; and gold on the coast of 
 California. 
 
 In low and fat countries, sand, loam, clay, sul- 
 phur, bog iron ore, and beds of gravel, are found 
 in alluvial soil. 
 
 In the loam and sand, great beds of bituminous 
 wood sometimes occur; of which the great under- 
 ground forest in Prussia, yielding amber in abun- 
 dance, is a remarkable instance. 
 
 The remains of plants and animals are found 
 only in those rocks which are newer than those 
 termed primitive, and rest upon them. Such re- 
 mains however occur in very variable proportion, 
 and even in some of the older secondary (or tran- 
 sition) rocks, no vestige of them is to be seen. 
 
 It has already been remarked, that in the tran- 
 sition rocks, which rest immediately on primitive 
 rocks, occur the remains of animals called zoo- 
 phites, which form the first link in the chain of 
 animated beings. These seem to be most abun- 
 dant in transition limestone ; in which, also, corals 
 of different species are found, approaching very 
 nearly, in external characters, to those now grow- 
 ing in tropical climates. 
 
 In transition trap and flinty slate, no organic re- 
 mains are to be seen. 
 
 Greywacke and grey wacke slate seldom contain 
 petrifactions ; in large tracts of country consisting 
 of these rocks, not a trace is to be seen ; in other?, 
 
139 
 
 some few are found, both of animals and vege- 
 tables. The animal remains seem to be nearly 
 the same as those found in the limestone. In 
 greywacke it is said that the remains of animals 
 of the serpent kind also occur : the vegetable 
 petrifactions appear like the stems and leaves of 
 palm trees, and of reeds. Grey vvacke slate eon- 
 tains the remains of those remarkable corals, 
 which are supposed to form the connexion be- 
 tween shells and corals. 
 
 The old red sandstone is the oldest of the fioelz 
 rocks : it contains but few petrifactions, and these 
 are principally of trunks and branches of trees, 
 which seem to resemble those of tropical climates. 
 
 The first flostz limestone comprehends three or 
 four varieties of rocks, in each of which animal 
 and vegetable remains are found : some of these 
 belong both to salt and fresh water; the remains 
 of a large amphibious animal of the genus moni- 
 tor have also occurred, which have been describ- 
 ed by Cuvier. 
 
 All the other fiostz rocks contain abundance of 
 animal remains, except the gypsum and trap for- 
 mation, in whieh they are rare : several of them 
 also enclose vegetable remains. In the second 
 floetz limestone, are found petrified fishes of vari- 
 ous genera and species, and fossil amphibious 
 animals; the stems and leaves of trees, and of 
 flowers, as of the ranunculus. In the third floetz, 
 or shell limestone, are found, together with pro- 
 digious quantities of shells, the fossil remains of 
 
140 
 
 fishes and of birds. Chalk sometimes contains 
 the teeth and bones of fishes; the remains of tor- 
 toises and crabs also occur in it. 
 
 In alluvial formations, petrifactions are distri- 
 buted, which often are so much rounded as to 
 show that they have suffered by attrition : the 
 organic remains are those both of fresh and of 
 salt water, and also of land and of amphibious 
 animals. The shells of oysters and of muscles 
 are plentifully found ; occasionally the teeth of 
 sharks. In some places, the bones of the horse, 
 the ox, and the stag occur, but differing from 
 those of the living species; in others, the bones 
 of elephants similar to those now inhabiting Asia 
 and Africa, and of the rhinoceros and hippopota- 
 mus ; in others again, the bones of several extinct 
 species of the elephant; and of an elk, formerly 
 an inhabitant of Ireland. 
 
LECTURE V. 
 
 Of Minerr.l Veins Of Salt Deposites Of Coal Depoiites Of Volca- 
 noes Of the Deluge Of the Internal structure of the Earth Corv- 
 cluding Observations. 
 
 - OF MINERAL VEINS. 
 
 IN treating of veins, we have a two-fold object. 
 They merit our attention in respect to the extra- 
 ordinary circumstances which attend them in all 
 countries in which they occur ; and also on ac- 
 count of their being the chief mineral dcposites. 
 
 But mineral deposit es are of two kinds ; for 
 metalliferous ores are largely found in beds, as 
 well as in veins. 
 
 Mineral beds are for the most part horizontal ; 
 and are found both in primitive and secondary 
 countries, of various elevation. 
 
 The ores of copper, iron, and lead occasionally 
 occur together in beds in primitive mountains ; 
 and sometimes gold and silver are intermixed 
 with them. Cobalt, and certain ores of mercury, 
 also occur in beds. Almost all the metalliferous 
 ores in the great mining district of Sweden, are 
 in beds in primitive mountains. Lead, zinc, and 
 iron ores occur abundantly in beds ia secondary 
 mountains. 
 
 In England, some ores are found in beds; but by 
 far the greatest mineral deposites of this country 
 are in veins : it is uniformly the case in Cornwall. 
 
142 
 
 A vein may be described as a fissure that has 
 been afterwards filled up with several different 
 substances. 
 
 Hurnboldt observed a vein of calcareous spar 
 140 feet wide, traversing gneiss in the Alps of 
 Switzerland. Jameson observed a vein of por- 
 phyry-slate traversing sandstone, in the Isle of 
 Arran, nearly 160 feet wide ; and in Scotland, 
 veins ofpitch,stone and greenstone, from 10 to 100 
 feet wide. But these veins do not appear to have 
 been what may be termed metalliferous veins ; 
 which, for the most part, are much narrower. 
 
 It is said, that in most primitive metalliferous 
 mountains, veins extend but a few hundred fa- 
 thoms in length, and that their width does not 
 exceed two feet. 
 
 It has also been said, that a description of the 
 veins of Cornwall would, generally speaking, suf- 
 fice for those of almost every other country ; and 
 having heretofore given much attention to their 
 actual state, I shall confine myself chiefly to them, 
 and endeavour to give a general outline of their 
 direction, length, depth, width, dip, and contents. 
 
 But in these respects, veins have not such an 
 uniformity, as that the history of one would be 
 an history of the rest : almost every vein has 
 something peculiar in it ; something to interest 
 the geologist. 
 
 The metalliferous veins of Cornwall, that is, the 
 veins producing copper and tin, which are the 
 chief mineral productions of that county, run in 
 
143 
 
 the direction of nearly east and west; they may 
 vary a few points. There are, however, other 
 veins, that rarely contain any metallic substance, 
 which, for the most part, run north and south. 
 These two facts are extremely curious. 
 
 Metalliferous veins may sometimes be traced 
 along the surface of the earth, hy a certain ochre- 
 ous or rusty appearance ; but this is not very com- 
 mon. 
 
 A vein may be said, in some sort, to resemble a 
 deep cleft or crack in a field. This cleft, what- 
 ever might be its depth, must, of course, have a 
 direction under ground : either it would be quite 
 straight down, or it would have a slanting direction 
 beneath the surface. 
 
 The veins of Cornwall scarcely ever take a di- 
 rection quite straight down, or, in other words, 
 quite at right angle with the horizon ; but almost 
 always either dip, or incline away from that angle. 
 
 So that the metalliferous veins which run east 
 and west, dip or underlie either towards the 
 north or south ; and the non-metalliferous veins, 
 which run north and south, dip either towards the 
 east or west. 
 
 The length of no one vein in Cornwall has, as 
 yet, been satisfactorily proved. Some of them have 
 been traced two, or three, or even four miles 5 but 
 no instance has occurred in which a vein has been 
 known to stop. Nor has the miner ever yet seen 
 the bottom of a vein. The length and depth to 
 which veins extend, therefore, are not known. 
 
144 
 
 There are several mines in Cornwall upwards of 
 1000 feet in depth from the surface, and two or 
 three nearly, if not quite, 1300~feet deep. 
 
 Metalliferous veins differ exceedingly in regard 
 to their width. A vein containing tin ore, in a 
 mine called Whealan Coates, was only three inches 
 wide, but was so rich as to be worth working ; 
 while another, in a mine called Relistian, was 
 upwards of 30 feet wide, and was also very rich 
 in tin. Some of the veins; containing copper in 
 Herland mine, did not exceed 6 inches in width ; 
 and so continued for a few fathoms, but eventually 
 passed away east and west in mere strings, scarce- 
 ly thicker than paper; but these veins yielded cop- 
 per of a very rich quality. A copper vein in the 
 next hill, varied from 12 to 24 feet in width, and 
 was also very productive of copper. 
 
 But the generality of metalliferous veins, both 
 of tin and copper, are from one to three feet in 
 width : and these are preferred by the miner, be- 
 cause the ore they contain is generally less inter- 
 mixed with other substances, than that of wider 
 veins. 
 
 Hitherto we have been speaking principally of 
 metalliferous veins. There is yet one circum- 
 stance, and a very important one, in regard to 
 these,, that we must not fail to notice. These 
 veins are not filled with metalliferous ores. Were 
 that the case, the miner would defeat his own 
 object; because, as veins are very numerous, the 
 quantity of tin and copper produced by them, 
 
115 
 
 would be so great, as that tlie price he would 
 obtain for the ore would not defray the charges 
 attending his operations. The ores both of cop- 
 per and tin principally occur in quantities which, 
 though they may extend many fathoms every way, 
 generally occupy, in point of fact, but a small 
 comparative^portion of the vein, and are there- 
 fore properly enough termed bunches. 
 
 A question here naturally arises. With what 
 substances are the remaining parts of the veins 
 filled up ? These are occupied sometimes by 
 rocks, or by stony or earthy substances of various 
 descriptions ; or by rubble, or refuse matter that 
 seems to hare resulted from the ruin of some 
 parts of the neighbouring country. The non- 
 metalliferous parts of a vein, of whatsoever com- 
 posed, are commonly termed, by the miner, deads, 
 because they yield him nothing. Sometimes, 
 however, veins are found to have large empty 
 spaces; but this, in Cornwall, is not common. 
 Water is very abundant in veins, particularly in 
 those rich in tin or copper. On a large mine 
 it is not unusual to see two or three steam en- 
 gines, for the purpose of drawing the water. 
 These will raise and discharge into the neigh- 
 bouring valley, at least 1000 gallons of water 
 every minute, night and day. 
 
 The sides of metalliferous veins are generally 
 
 very determinate ; and are covered by a hard 
 
 dark-coloured crust, called by the miner^the walls 
 
 of the vein : and there generally runs down evri-r 
 
 O 
 
146 
 
 rein, a small vein of a whitish clayey substance, 
 which sometimes adheres to one, sometimes to 
 the other wall. 
 
 The ores of copper and the ore of tin (for of 
 tin there is but one description of ore, while there 
 are many of copper) do not often occur together 
 in the same vein to any great depth beneath the 
 surface. 
 
 At about 80 or 100 feet under the surface, the 
 first traces of copper or tin are usually found ; 
 rarely nearer to it than 80 feet. But when at last 
 they are found, it is not to be understood that 
 these ores consist of one close and compact mass : 
 on the contrary, they are generally mingled with 
 other substances, such as lead ore, iron pyrites, 
 the ore of zinc, accompanied by fluor spar and 
 quartz, &c. These are in some cases loose in the 
 rein ; in others, they are hard, and attached to 
 one or to both sides of it. 
 
 Sometimes the ores both of tin and copper are 
 found thus circumstanced together in the same 
 vein ; and when so found, it generally happens 
 that all trace of tin is soon lost. 
 
 If tin be first discovered, even without a trace 
 of copper, it is not unusual, that in the course of 
 sinking 80 or 100 feet more, all trace of it is lost, 
 and copper only is found. The vein of course 
 was at first called a tin vein ; but afterwards be- 
 came only a copper vein : and many of the most 
 productive mines in Cornwall have been exactly 
 so circumstanced. Nevertheless, in some veins. 
 
147 
 
 tin continues to be found to the great depth of 
 nearly 1 000 feet beneath the surface, almost with- 
 out a trace of copper. 
 
 But if, instead of tin, copper be first discovered 
 at the depth of 80 or 100 feet, it seldom or ever 
 happens that tin is found below it in the same 
 vein. 
 
 In one or two of the deepest mines in the coun- 
 ty, both copper and tin have continued down to- 
 gether, in the same vein, to the greatest depth at 
 which it has been seen by the miner ; sometimes 
 one prevailing, sometimes the other. 
 
 It has been stated, that the tin and copper veins 
 run nearly east and west ; but that the veins which 
 run nearly north and south, scarcely ever contain 
 a trace of tin or copper : in some few instances, 
 they have been found to contain the ores of silver, 
 lead, cobalt, and iron ; others have produced an- 
 timony. 
 
 These north and south veins are usually filled 
 by quartz, or a whitish or bluish clayey substance, 
 or an ochreous substance ; and sometimes by all 
 three. When a vein of this description meets with 
 a vein containing tin or copper, it passes through 
 the tin or copper vein; and sometimes, as it were, 
 splits it into numerous little branches; the north 
 and south vein continuing its course straight for- 
 ward without interruption. 
 
 Not only is this curious effect produced, but 
 also another of a much more extraordinary nature. 
 In searching for the tin or copper vein on the 
 
14S 
 
 other side of the north and south vein, it some- 
 times cannot be found for a length of time, nor 
 without much labour and expense : forty years 
 have been spent in such a search. 
 
 For, instead of continuing its course, instances 
 Lave been known in which the tin or copper vein 
 has bee'n again found 120. or even 450 feet, north 
 or south of that part of it, on the other side of 
 the north and south vein. 
 
 North and south veins vary in width from one 
 
 Inch, to ten or twelve feet ; but, whatever be their 
 
 width,, they always divide tin or copper veins, 
 
 ft'id generally alter their course ; or, in the lan- 
 
 of the miner, kea?c them out of their course. 
 
 In some parts of the mining districts of Corn- 
 vrall, metalliferous veins are so numerous, that 
 'with the minor, the question is not where a vein 
 can be found, but where he will be most likely to 
 meet with one productive of copper or tin. Years 
 of labour, and large sums of money, are often ex- 
 Jjended in vain, because there is no circumstance 
 by which he can determine, with certainty, that 
 Lis efforts will be successful. 
 
 There are many mines through which several 
 veins of copper and tin take their course, very 
 near to each other. 
 
 If a copper vein meets with a tin vein, it is 
 universally the case, that the copper vein passes 
 through that of tin, and generally heaves it out of 
 its course, greatly to the inconvenience and loss 
 of the miner, who is often puzzled to find if again. 
 
/ 
 
 
Plate, 4. 
 
 n TIN CROFT Copper &Tw 
 
 Veins in the P INK Mine 
 
149 
 
 There are still other, and, if I may so say, sub- 
 ordinate veins found in Cornwall. The explana- 
 tion of their nature and effects would trespass too 
 greatly on your time : they rarely contain any 
 metalliferous substance, but they occasion prodi- 
 gious vexation and expense to the miner. 
 
 -* 
 
 In elucidation of what has just been said of the 
 phenomena attending the veins in Cornwall, I 
 shall offer for your inspection a sketch of those 
 which actually occur in two mines called Tin 
 Croft and the Pinky (see plate 4.) Let us sup- 
 pose that the upper square figure represents the 
 hill in which Tin Croft mine is situated : it is not 
 an exact representation of it, because that hill has 
 a gentle declivity on every side ; but for the sake 
 of familiar illustration, I have supposed it to be 
 cut away on the north, the south, the east, and 
 the west sides, and that the soil is taken from the 
 surface down to the rock, in order more clearly 
 to show the run of the several veins upon it, and 
 their directions beneath it. 
 
 All these veins are found in Tin Croft mine, in 
 less than half a mile from north to south. The 
 upper part of the square figure represents the 
 field in which the mine is situated. We shall 
 observe that there are three veins of copper, 
 (coloured red;) three of tin, (black;) and one 
 yielding both copper and tin, (red and black.) 
 These veins run on the surface east ajad west, 
 and are intersected by a vein running north and 
 O 2 
 
150 
 
 south (bluish) which is not metalliferous ; and we 
 shall further observe, that the copper and tin veins 
 were not merely intersected, but also, that the 
 parts of them on the western side of the north 
 and south vein, were ' heaved' out of their regu- 
 lar course towards the south. 
 
 Let us remark the downward direction of the 
 popper and tin veins; not one of them runs straight 
 down ; they dip or underlie more or less, either 
 towards the north or south. Two of the copper 
 reins intersect one of the tin veins, and pass 
 through it, without altering its direction. 
 
 It has been said, that the miner has never seen* 
 the bottom of a vein. Three of the veins in Tin 
 Croft seem to stop; the fact is, that the miner did 
 not pursue these veins to so great a depth as the 
 others ; their direction beneath where they seem 
 to stop, is not exhibited, because it is not known. 
 
 From one of the copper veins which underlies 
 a little towards the south, two branches go off, 
 underlying much quicker towards the north: 
 the veins of Cornwall rarely branch off in this 
 manner. 
 
 The section of the Pink mine is a remarkable 
 instance in proof of the assertion that copper veins 
 meeting with those of tin always duide, and ]pas$ 
 'through, and mostly * heave 9 them., 
 
 Let us first notice the summit of the lower 
 square figure, (pi. 4.) which represents the run of 
 the veins on the surface of the Pink mine ; in 
 which there were four east and west, or metalli- 
 
151 
 
 ferous veins, two being of copper (coloured red,) 
 and two of tin (black.) These veins were inter- 
 sected by a north and south vein (bluish) that 
 was not metalliferous ; which heaved the parts 
 of the copper and tin veins on the western side 
 of it, more towards the north than are those parts 
 of them on the eastern side of it. 
 
 j* 
 
 The tin vein ran near the southern extremity 
 of the mine, underlying in its downward direction 
 greatly towards the north. It will be noticed 
 that the copper veins underlie in the contrary 
 direction, that is, towards the south. One of 
 them, meeting with the tin vein in its course, in- 
 terrupted it, and 4 heaved' that part of the tin 
 vein on the south of the point of intersection, 
 twenty-four fathoms nearer the surface. It was 
 afterwards found that the tin vein was again in- 
 terrupted by another copper vein, and again 
 heaved towards the surface 3 though only about 
 ten fathoms : a third time it was cut through by 
 still another copper vein, which does not appear 
 on the surface of the mine, and again heaved, 
 though less than before, towards the surface. 
 
 There are yet some important points respecting 
 mineral veins, on which I purpose saying a few 
 words. I mean in regard to the probable manner 
 in which they were formed, and by what means 
 they were filled. 
 
 They who contend that the great masses of the 
 globe are altogether what they now are, through 
 
152 
 
 the agency of frc, assert that veins were formed 
 by the contractions which took place in those 
 masses while cooling, and that they were filled 
 from below : in other words, that the contents 
 of veins were protruded into them from the inter- 
 nal parts of the globe, by the agency of fire. 
 
 Those who, on the contrary, contend that the 
 great masses of the globe are what they now are 
 through the agency of water, assert that mineral 
 veins were originally open fissures or rents, 
 caused by the subsiding of the great masses of the 
 globe ; and that these fissures were filled from 
 above, receiving into them the metals which 
 formed a part of a great chaotic fluid. 
 
 I am not now about to enter into an exami- 
 nation of the comparative merits of these two 
 doctrines, but shall probably hereafter say a few 
 words on this part of the subject. 
 
 I cannot, however, pass by one or two obser* 
 vations in regard to the relative ages of veins. 
 
 It has been said that copper veins, meeting in 
 their course with those of tin, always divide and 
 pass through them. This seems clearly to show 
 that tin veins are the oldest, or they could not 
 have been so divided. 
 
 It has also been said that the north and south, 
 or non-metalliferous veins, always divide the veins 
 of copper as well as those of tin. This clearly 
 shows that the tin and copper veins were both 
 older than the north and south veins, or they 
 could not have been so divided by them. 
 
153 
 
 But other veins, not containing any metallic 
 substance, are occasionally found ; which, as they 
 divide and pass through every one of the fore- 
 mentioned, are therefore of still later formation. 
 
 OF SALT DEPOS1TES. 
 
 IT was slated during the last evening, that de- 
 
 posites of salt are principally found amongst those 
 
 !i are by Werner termed the flcetz or flat 
 
 rocks 5 hut which, by other geologists, are ranked 
 
 among those called secondary rocks. 
 
 Clay, sandstone, and gypsum, almost invariably 
 accompany rock salt, either above or below it ; 
 sometimes both above and below it. 
 
 The countries in which large deposites of salt 
 are found, are for the most part flat ; they do not 
 often exceed that elevation which is termed hilly. 
 
 In Germany, but few instances of the rock salt 
 formation occur; but it is said that an uncommon- 
 ly great deposition* of it maybe traced with little 
 interruption, from the Black Sea nearly to the 
 Alps. It abounds in Spain ; but is not very com- 
 mon in Russia, or generally in northern countries. 
 Nevertheless, there are said to be two whole 
 mountains in Astmcan entirely composed of it. 
 It is abundant in Persia; the isle of Orraus in the 
 Persian Gulf almost wholly consists of rock 
 salt. Whole mountains of it also occur in Tunis 
 
154 
 
 and Algiers, in Africa. It is found in Ne\v 
 South Wales ; and not long since a mountain of 
 salt, of an immense height,was discovered near the 
 Missouri river in America, eighty miles long and 
 forty-five miles wide, the surface of which is barely 
 covered with earth ; neither tree nor shrub is 
 growing upon it. 
 
 But many countries are nearly without salt. 
 At Delhi and Agra, the capitals of Hindustan, its 
 price is 2s. 6d. per pound : and it is said to be so 
 scarce in the interior of that country, west of 
 Thibet, that the natives use cakes of salt, sealed 
 up and bearing the stamp of their prince, as 
 money. 
 
 Perhaps the most extensive deposition of rock 
 salt in the world, occurs in Wiclitska.near Cracow 
 in Poland, at the northern extremity of a branch 
 of the Carpathian mountains. It has been worked 
 as a mine since the year 1251, and its excavations 
 are said to extend more than a league from east 
 to west. The salt is of an iron gray colour, in 
 which are found cubes of a pure white. 
 
 This mine was visited by our countryman 
 Wraxall ; from whose account of it some idea of 
 its vastness may be gathered. He says, * After 
 being let down by a rope two hundred and thirty 
 feet,our conductors led us through galleries, which 
 for loftiness and breadth seemed rather to resem- 
 ble the avenues to some subterraneous palace, 
 than passages cut in a mine : they were perfectly 
 dry in every part, and terminated in two chapels 
 
155 
 
 composed entirely of salt, hewn out of the solid 
 mass. The images which adorned the altars, as 
 well as the pillars and ornaments, were all of the 
 same transparent material; the points and spars of 
 which, reflecting the rays of light from the lamps 
 which the guides held in their hands, produced 
 an effect equally novel and beautiful. Descend- 
 ing lower into the earth, by means of ladders, I 
 found myself in an immense hall or^cavern of salt, 
 many hundred feet in length, breadth, and dimen- 
 sions, the floor and sides of which were cut with 
 exact regularity. One thousand persons might 
 dine in it without inconvenience, and the eye in 
 vain attempted to define or trace its limits. No- 
 thing could be more sublime than this vast subter- 
 raneous apartment, illuminated by flambeaux, 
 which faintly discovered its prodigious magnitude, 
 and left the imagination at liberty to enlarge it 
 indefinitely.' 
 
 Hitherto we have not mentioned the deposites 
 of salt, and the salt or brine springs, which are so 
 abundantly found in our own country. A descrip- 
 tion of some of these is my principal object. The 
 chiefest are those of Droitwich, in Worcester- 
 shire, and of Northwich, in Cheshire, which are 
 the most productive of all. 
 
 I proceed first to the brine springs at Droitwich. 
 
 These springs are said to be mentioned in the 
 Domesday Survey, which was finished in*10S7. 
 
 The prevailing rock around Droitwich is a 
 
156 
 
 brownish red sandstone, considered to be the old 
 red sandstone of Werner. 
 
 At this place the brine springs are four in 
 number, all situated within a square furlong; and 
 as no new pit has been sunk within the last thirty 
 years, we have not a very accurate account of the 
 strata through which they passed, before they ar- 
 rived at the brine. From the account given by 
 Dr. Nash, in his history of Worcestershire, we 
 gather these facts : that four pits were variously 
 sunk through from thirty to fifty-five feet of soil 
 and rock, when they arrived at a stratum of gyp- 
 fium, varying from 102 to 150 feet in thickness : on 
 passing through this, they suddenly arrived at the 
 salt brine, which, immediately on their arriving at 
 it, rose quickly to the surface, and overflowed. In 
 each of the pits the brine was twenty-two inches 
 in depth : in each also it was ascertained that it 
 was immediately resting on a bodjg of rock salt. 
 Into this rock salt thpy bored two feet and a half, 
 without passing through it; the brhie being their 
 object. 
 
 From this account, the principal information 
 we gather, is, that the water of these springs is 
 impregnated with salt,* by a body of rock salt ; and 
 that, as the* brine rises perhaps 180 feet to the 
 surface, and overflows, the source of these springs 
 must be situated in much higher ground than that 
 in which the pits are sunk. The brine is'perfectly 
 limpid, and contains about one-third its weight 
 of salt. 
 
15? 
 
 The quantity of brine whit-h issues from these 
 four pits is immense. That which is u=cd, bears 
 but a small proportion to that which runs to 
 waste : nevertheless, the quantity of salt annually 
 made from these four pits is about 16,000 tons; 
 two-thirds of this are consumed in England, and 
 pay a duty of about 320,000 per annum. The 
 market price of the salt is 31 per ton, 30 of 
 which is duty. 
 
 We come now to the great beds of rock salt at 
 North wich in Cheshire. 
 
 These beds are known to extend one mile and 
 a half, north-east and south-west, and are upwards 
 of three quarters of a mile wide: there are two 
 beds, lying one beneath the other. 
 
 The strata above the upper bed, consist of gyp- 
 sum, and of alternating beds of variously coloured 
 marl, red, blue, and brown ; some of them are so 
 porous, as that it has been ascertained that 360 
 gallons of water rise through them in a minute ; 
 a circumstance that greatly impedes the sinking 
 of the pits. It is remarkable, but it is well ascer- 
 tained, that the various strata above the upper 
 bed of rock salt contain no marine fossils. These 
 strata are from 105 to 120 feet thick ; they repose 
 on the first bed of salt, which is from sixty to 
 ninety feet thick: between the first and second 
 beds of salt lies a stratum of indurated marl, thirty- 
 six to forty feet in thickness. So that the surface 
 
 of the second or lower bed of rock salt "is about 
 P 
 
153 
 
 220 feet from the surface of the land. Into this 
 second bed of salt they have sunk 132 feet, with- 
 out having found the bottom of it. 
 
 The suit of these mines is, for the most part, of 
 a reddish hue, arising from some admixture of 
 iron; and it is generally so hard, that the blast by 
 gunpowder is employed in breaking it down. The 
 lower part of the lower bed is the purest : and in 
 it there are considerable cavities, about 16 feet in 
 height; in which, occasionally, pillars of salt are 
 left, six or eight yards square, which form the 
 supports of the roof, The cavities are worked 
 into aisles or streets ; which, when illuminated by 
 candles fixed to the sides of the rock, give a bril- 
 liancy of effect that is singularly striking ; and, it 
 is said, almost appear to realize the magic palaces 
 of the eastern poets. 
 
 Some idea of the vast magnitude of the Cheshire 
 saltdeposites may be formed, when it is mentioned 
 that its many mines yield 16,000 tons for home 
 consumption annually, and that 140,000 tons more 
 are annually exported from Liverpool. 
 
 We come now to the consideration of the means 
 by which these vast formations of rock salt were 
 deposited. It must be obvious, that all that caa 
 be said will amount to no more than theory : a 
 theory which presents some objections, while its 
 basis seems reasonable in itself. 
 
 The Cheshire salt beds occupy vallies sur- 
 feuuded by bills of secondary formation; and the 
 
159 
 
 upper surface of the upper bed of salt is about 40 
 feet below low-water mark at Liverpool. The 
 numerous facts already adduced, have led us de- 
 cidedly to adopt the belief that the sea must have 
 stood at an elevation greatly above the general 
 level of the earth. Is it not, therefore, reasonable 
 to presume that these beds of salt were deposited 
 by the sea ; and that the beds of clay lying be- 
 tween and above them resulted from the ruin of 
 rocks ? 
 
 The arguments in support of this theory are, 
 
 That the upper surface of these deposites of salt, 
 are 40 feet under low-water mark. 
 
 Tliat, in the beds of marl, it is not unusual to 
 find fragments of the older rocks ; such as large 
 portions of granite, showing marks of attrition. 
 
 That these deposites of rock salt contain some 
 salts, as the sulphate of soda, which also is found 
 in the waters of the ocean. 
 
 The principal argument against this theory is, 
 that no sea shells or weeds are found above or 
 below these beds. 
 
 But, perhaps, we ought to take into considera- 
 tion that there are beds of salt near Salzburg in 
 Austria, which are stated by Von Buch to be 
 2975 feet above the sea j and that the salt mines 
 in the Tyrol are yet higher. 
 
 We have, however, heretofore produced evi- 
 dence that the sea has been at much greater eleva- 
 tions than this 5 and has deposited ahnfcst entire 
 strata of sea-shells, at such elevations. 
 
IGO 
 
 OF COAL DEPOSITES. 
 
 Deposites of coal are not only of great import- 
 ance, but are far more abundant and more gene- 
 ral than they are commonly supposed to be. 
 
 Coal, in greater or less quantity, and of differ- 
 ent qualities, is found in most countries : in Hol- 
 land, Germany, Saxony, Portugal, Switzerland, 
 Sweden, China, Japan, New Holland, and in 
 North and South America. Buffon states, that in 
 his time there were no fewer than 400 collieries 
 worked in France. The deepest coal mine in the 
 Avorld is near Namur ; it is stated to be 2400 
 feet, or nearly half a mile, in depth. 
 
 Coal is found at various elevations ; but almost 
 all the greatest deposites are in low situations ; 
 where it occurs in beds lying over each other, of 
 various thicknesses, having between them one or 
 more earthy deposites, or beds of stony matter. It 
 is remarkable that though these beds of coal are 
 nearly horizontal, they are not quite flat, but 
 generally dip near the middle, where they are 
 found thicker than at the sides ; so that a section 
 would give the idea of the form of a boat. 
 
 Both in this country and in others, coal is found 
 at elevations much above the sea ; and at one 
 place in France, the strata, instead of being, as is 
 usual, nearly horizontal, are nearly vertical. 
 I bave lately been informed that there is a con- 
 siderable deposite of coal in the immediate 
 
161 
 
 neighbourhood of the great silver mine of Jauri- 
 cocha in Peru, which is about three miles above 
 the level of the sea. 
 
 But it is considered that there are three forma- 
 tions of coal. I shall begin with the newest, on 
 account of its being of the least importance. 
 
 The newest coal formation occurs in alluvial 
 soils. In thisr, the strata of coal are not parallel 
 with each other ; and the earthy strata that are 
 found with it are those of sand, clay, and gravel. 
 
 The newest coal consists almost exclusively of 
 earthy brown coal, and biturnenized wood, of 
 which there isa considerable deposite near Exeter. 
 
 The coal formation, next in point of age, occurs 
 in that deposition to which Werner has given the 
 name of the newest floetz trap; the result, as he 
 conceives, of deluges. In this the coal is gene- 
 rally covered with clay, or basalt, in which are 
 found neither vegetable impressions nor animal 
 remains. The strata are not so numerous as in 
 the formation presently to be described, nor are 
 they so perfectly parallel with each other. The 
 chief collieries of Scotland, of the central part of 
 France, and of Bohemia, are of this description ; 
 these yield principally the varieties termed pitch 
 coal and moor coal, not often slate coal. 
 
 The next, or oldest, is called the independent 
 coal formation, because the individual depositions 
 or beds, not being connected, are independent of 
 each other. This formation consists of extensive 
 and remarkably parallel strata of coal, covered 
 P % 
 
 
by strata of indurated clay called shale, contain- 
 ing the impressions of vegetables, and sometimes 
 the remains of fresh water shell-fish. The shale 
 is always wanting in the newer deposites of coal 
 already described, but always accompanies the 
 oldest. The great coal deposites of our own 
 country, are principally of this latter description ; 
 and in some of these there are as many as twenty- 
 beds of coal, varying in thickness from G inches to 
 6 or 8 feet. Between the beds or strata of coal, is 
 one or more beds or strata of various coloured 
 sandstone, clay, bituminous shale, or rubble stone, 
 (called by the miners rotten stone) or argillaceous 
 iron ore, or of secondary limestone. This for- 
 mation of coal is also plentifully found in some of 
 the countries already enumerated 5 and two cir- 
 cumstances are worthy of notice. The first, that 
 the strata occurring above and below this forma- 
 tion, are in all countries very much alike, if not 
 absolutely the same : the second, that although 
 the shale, already described as lying above the 
 coal, contains impressions of vegetables, and the 
 remains of fresh water fish ; it is remarkable that 
 in every country the strata of various substances 
 which lie between the strata of coal, scarcely 
 ever contain any vegetable impressions or organic 
 remains. 
 
 During the last evening, in speaking of what 
 may be termed the order every where observable 
 in the disposition of great masses which form, 
 th^crust of the globe^ it was stated that deposites- 
 
163 
 
 of coal are principally found resting upon secon- 
 dary rocks : and this is proved to be the fact in 
 respect of our own great deposites, as well as those 
 of other countries. 
 
 Our own deposites are our im mediate objects. 
 Three extensive collieries in Flintshire in North 
 Wales, those of Glamorganshire in South Wales, 
 of Coalbrootedale in Shropshire, and of Kingwood 
 near Bristol, all commence in the immediate vi- 
 cinity of secondary limestone ; and the still more 
 extensive deposites in the North of England, at 
 Newcastle and Whitehaven, rest upon secondary 
 freestone or sandstone, abundantly used as grind- 
 stones. 
 
 These two extensive collieries of Newcastle and 
 Whitehaven, situated, the one on the north-east 
 and the other on the north-west coast, it is now 
 confidently believed, from the great similarity 
 existing in their strata, form but one deposite, 
 consisting of many strata, which extend directly 
 across the island from one place to the other; 
 and even far beyond each, beneath the sea. At 
 Whitehaven the workings extend a mile under 
 the ocean, at about 600 feet below its bottom ; 
 and it is asserted that the quality of the coals is 
 still improving as the miner advances in this di- 
 rection. 
 
 From this great deposite of coal alone, it is 
 calculated that 28 millions of tons are raised an- 
 nually ; nevertheless, it is also calculated that 
 enough yet remains for the consumption of 1000 
 years to come* 
 
164 
 
 A mere list of the strata that have been cut 
 through to the depth of the mines at Whitehaven 
 and Newcastle, would form a dry and uninteresting 
 detail. 
 
 In the Restoration pit in St. Antony's colliery 
 at Newcastle, which is 810 feet deep, the miner 
 passed through 73 strata of various substances ; 
 of which 16 are coal. The first 6 strata of coal 
 do not exceed 8 inches in thickness ; 2 are 1 foot 
 thick; 6 varied from 1 foot 6 inches to 4 feet; 
 1 is of 6 feet ; and the thickest, which is the 
 lowest, is of the thickness of 6 feet 6 inches. 
 
 In a mine at Preston Hows at Whitehaven, 
 which is 642 feet deep, the miner passed through 
 117 strata, of which 17 are of coal ; the thickest 
 of these, which is the lowest, is 7 feet 10 inches. 
 
 All that can be said upon the origin of coal 
 must be theoretical, and perhaps very remote from 
 the truth : it is, however, certain, that there are 
 few, if any, varieties of coal, which do not present 
 more or less of the texture of wood. This ap- 
 pearance may be traced from the bitumenized 
 wood, which still bears, though approaching in 
 its nature to coal, the trunk, the branches, and 
 even in some instances the very leaves of trees, 
 through all the varieties of coal, into the most 
 compact, slaty kind, of the oldest formation. In 
 some, particularly from certain districts, the 
 fibrous texture of wood is certainly remarkable ; 
 and the greater part of those who have given 
 their attention to the probable origin of coal ? 
 
165 
 
 consider it to have resulted from vegetable re- 
 mains. 
 
 That there still exist great underground forests 
 is unquestionable. That in Prussia, yielding- 
 amber, may be quoted as an instance : and if 
 coal be really of vegetable origin, this forest may 
 hereafter in^part yield important service to man, 
 in the shape of coal. The immense bridge, not 
 less than three miles in length, now existing and 
 still receiving additions, on the Missouri, a river 
 in North America, and consisting wholly of the 
 trunks of trees, stopped in their progress down 
 that river, may furnish coal to nations after tho 
 lapse of thousands of years. 
 
 But though some varieties of coal seem unques- 
 tionably of vegetable origin, certain others are 
 not referable to it so decidedly : especially the 
 slate coal of the oldest formation. This is fre- 
 quently found in fragments of determinate shapes^ 
 particularly in that of a four-sided rhomboidal 
 prism, presenting angles agreeing perfectly ia 
 measurement with those of crystals of mica. 
 
 Upon the whole, it must be acknowledged that 
 the origin of coal is yet but little understood. 
 
 OP VOLCANOES. 
 
 On the subject of volcanoes, so much both of 
 lact and. of theory has been written, that it is 
 
16$ 
 
 extremely difficult to compress into a narrow 
 compass, any satisfactory detail respecting them 
 or their origin. 
 
 Scientific writers hare divided volcanoes into 
 two kinds : pseudo or false volcanoes ; and true 
 volcanoes. 
 
 Pseudo volcanoes usually occur in low situations, 
 sometimes in hilly country. They are discoverable 
 by a sensible heat, sometimes by smoke ; more 
 seldom by flame. Sulphureous deposites and 
 warm springs occur in their vicinity. 
 
 Pseudo volcanoes are almost always situated in 
 the independent coal formation } and are considered 
 to be caused by the spontaneous or accidental 
 inflammation of beds of coal. Volcanoes of this 
 description are to be observed in Bohemia, in 
 Scotland, in England, and many in Kamschatka. 
 Of true volcanoes the number is considerably 
 great. From the accounts of travellers, it appears 
 that the whole number now in existence, most of 
 which are occasionally in a state of activity, 
 amounts to 193. They are thus distributed, ac- 
 cording to Jameson, but it seems doubtful whe- 
 ther some pseudo volcanoes are not included. 
 Continent of Europe 1 
 
 European islands 12 
 
 Continent of Asia 8 
 
 Asiatic islands 58 
 
 African islands 8 
 
 Continent of America 87 
 American islands 10 
 
167 
 
 In almost every country hills arc found, which, 
 from their shape, and the character of the sur- 
 rounding masses, have, hy some authors, been con- 
 sidered as extinct volcanoes : many of these are 
 no longer supposed to be of volcanic origin; but 
 it is certain that in Auverge, and in some other 
 districts in France, as well as some in Spain, the 
 remains of volcanoes are still to be seen ; because 
 the nature of their masses is indisputably volcanic. 
 Volcanoes are found at almost every elevation 
 between the level of the sea and that of Cotopaxi 
 in South America, which is 18,880 feet above it. 
 Indeed, in many instances, volcanoes have burst 
 from the bottom of the sea. Not long since, a 
 considerable island was thus formed in one night, 
 in the great Southern ocean ; and many islands in 
 the Archipelago, as, for instance, that called San- 
 toniri, which is eight miles long, owe their origin 
 to submarine volcanoes. The island of Teneriffe 
 is about 45 miles in length, and 20 in breadth. 
 There is an interesting and valuable memoir in 
 the 2d vol. of the Geological Transactions,* de- 
 scribing a vi^it to the summit of its peak, which 
 rises to an elevation of 1 1,000 feet above the sea. 
 It appears, that in one district of this island there 
 are 7 cones, exhibiting no traces of culture, no 
 appearance of vegetation; that the soil of the 
 island is altogether volcanic; that in one vallejr 
 there are 100 strata of lava; and that every rock 
 and stratum in a word, the whole island, is the 
 production of volcanic eruptions. 
 
 * By the Hon. Henry Grey Bamet, M. P. Pre*. Geological Soc, 
 
168 
 
 But our present object is with volcanoes, at 
 being the cause of the ruin, and as forming anew, 
 some of the constituent masses of the crust of the 
 globe. Therefore, after some general and concise 
 account of the nature of true volcanoes, we shall 
 proceed to the consideration of the geological 
 nature of one or two mountains, wherein those 
 are situated of which we have the most authentic 
 accounts, as of Vesuvius and jEtna; concluding 
 our slight outline, (for it is a slight outline alone 
 that I shall be able to present,) with such an ac- 
 count of the probable origin of volcanoes as the 
 researches of the scientific afford. 
 
 Volcanoes have usually a conical shape, and 
 are provided sometimes with one, sometimes with 
 several mouths or craters. 
 
 In an active state, they occasionally eject smoke, 
 vapour, flame, glowing and melted masses, and 
 more rarely, water. 
 
 The occasional eruptions of large volcanoes 
 are usually accompanied with earthquakes and 
 lightning. 
 
 But when a volcano ejects only smoke, it is 
 considered to be in a state of rest. This smoke 
 is said to be composed of steam, or watery va- 
 pour, the muriatic and sulphureous gases; also 
 of azote, carbonic acid, and hydrogen gas. If the 
 smoke be black, it contains much carbonaceous 
 matter ; when gray, or of a white colour, it is 
 principally composed of aqueous vapour. 
 
 In a greater state of activity, glowing masses 
 
169 
 
 are ejected. These do not follow at regular pe- 
 riods, except in one instance that will be noticed 
 presently. They are generally accompanied by a 
 noise, proportioned in loudness to the magnitude 
 of the stones that are projected, and the height to 
 which they ascend. Ashes also are occasionally 
 thrown out in prodigious quantities. * 
 
 But the most striking phenomena exhibited by 
 volcanoes, are the flowing streams of melted mat- 
 ter tailed lava, from their craters. These are 
 usually preceded by earthquakes. 
 
 The instance just now mentioned, as an excep- 
 tion to the rule that the eruptions of volcanoes 
 are not periodical, is that of Stromboli, one of the 
 Lipari islands. 
 
 According toDolomieu, the crater of Stromboli 
 does not exceed fifty paces in diameter. This 
 volcano is mentioned by Pliny ; and, it is said, that 
 from time immemorial, its eruptions have taken 
 place about every 7 or 8 minutes. 'I saw it dart,' 
 says Dolomieu, l during the night, at regular in- 
 tervals of 7 or 8 minutes, ignited stones, which 
 rose to the height of more than 100 feet, forming 
 radii a little diverging ; but of which the greater 
 part fell into the crater, while others rolled even 
 to the sea. Each explosion was accompanied by 
 a burst of red flame. The stones ejected are of 
 a lively red; and sparkle, having the effect of arti- 
 ficial fire works. The approach of the eruptioii 
 is not announced by any noise or dull murmur in 
 the interior of the mountain.' 
 
170 
 
 Vesuvius is a mountain of about 30 miles in 
 circumference, and 3600 feet in height. The first 
 recorded eruption is that of the year 79, which 
 covered the towns of Pompeii and Herculaneum 
 with a shower chiefly of sand and ashes of 80 feet 
 in depth : but as late researches beneath this bed 
 of ashes, and even to the foundations of the houses 
 of Pompeii and Herculaneum, have proved that 
 their streets were paved with volcanic matter, no 
 doubt can be entertained that Vesuvius was a vol- 
 cano at a. much earlier period. Since the erup- 
 tion just noticed as having happened in the year 
 79, thirty different eruptions of Vesuvius, of differ- 
 ent degrees of violence, have been recorded. 
 
 In 1538, a mountain, principally of sand and 
 ashes, 3 miles in circumference, and J of a mile in 
 height, was thrown up in one night. 
 
 An eruption of great violence, but inferior in 
 this respect to that just noticed, was particularly 
 described by Sir William Hamilton. It occurred 
 in 1767, and lasted, at intervals, several days and 
 nights. Streams of lava flowed, and prodigious 
 quantities of ashes ascended, which, it is said, fell 
 in Manfredonia, 100 miles distant from Vesuvius, 
 in two hours after they were projected. Vast 
 masses of stone were likewise thrown out by this 
 eruption, which was accompanied by earthquake 
 and lightning; many of these masses were mea- 
 sured by Sir William Hamilton ; the largest of 
 them was 108 feet in circumference, and 17 in 
 length, but there were several not much inferior 
 ia bulk. 
 
171 
 
 A stream of lava issued after the eruption of 
 1784, one mile wide and about twelve feet deep. 
 
 A particular account of volcanic eruptions 
 would prove highly interesting ; but our business 
 with volcanoes is geological. I shall, therefore, 
 content myself with saying, in respect to the 
 nature of tht eruptions of ^Etna, that the project- 
 ed matters much resemble those of Vesuvius. 
 -Etna is above 10,000 feet high, auil is about 130 
 miles in circumference : it was noticed as a vol- 
 cano by Diodorus Slculus, 450 years before the 
 Christian era. 
 
 But there is so great a difference in the nature 
 of the substances thrown out by some of the Ame- 
 rican volcanoes, that they merit particular notice. 
 Several of these are situated in mountains more 
 than 10,000 feet high, and that of Cotopaxi, which 
 is the highest, is 18,880 feet above the sea. Ac- 
 cording to Humboldt, these volcanoes scarcely 
 ever throw out lava, but chiefly slag, ashes, a sub- 
 stance resembling pumice, and vast quantities of 
 water, with an earthy or slimy mass, which often 
 contains vast numbers of fishes. Hence, in the 
 accounts of the tremendous volcanic eruptions 
 that have taken place in the province of Quito, 
 we hear only of overflowings, or of bodies being 
 buried in slimy mud ; never of the burnings that 
 characterize the eruptions of some other volca- 
 noes. When the volcano of Carguairazo fell down, 
 on the night of the 16th July, 1698, it over- 
 flowed a tract of country 16 or 18 square miles, 
 
172 
 
 with slimy mud. The number of human beings 
 destroyed was so great, that the bodies were in- 
 terred in heaps. During the great earthquake of 
 the 4th February, 1797, 40,000 human beings 
 were destroyed by the water and mud that issued 
 from the mountains. 
 
 The substances ejected by pseudo volcanoes 
 are, burnt clay, porcelain-jasper, earth-slag, co- 
 lumnar clay, iron-stone, and polishing slate. 
 
 Those ejected by true volcanoes are, granular 
 limestone imbedding various minerals, most of 
 them crystallized, and occasionally granite, mica- 
 slate, greenstone, and sandstone : these substances 
 have not undergone fusion, and frequently con- 
 tain crystals of various substances unaltered ; 
 pumice, obsidian or volcanic glass, slime called 
 volcanic tuiF, sulphur, and muriate of ammonia, 
 are, in general, in greater or less quantity, also the 
 products of volcanic eruptions. 
 
 Of the origin of volcanoes, we can only reason 
 from the nature of the substances they present to 
 us. Many have been of opinion that volcanic 
 mountains are wholly the results of the matter and 
 masses ejected during eruptions, and that the real 
 seat of volcanoes is very deep in the earth. Of 
 the depth at which they may be situated, we know 
 but little : but there seerns no reason for believing 
 that volcanic mountains, in the general, have been 
 thrown up by the volcanoes that yet continue 
 within them, or beneath their base. 
 
 Of the actual nature of Vesuvius as a mountain, 
 
173 
 
 we know but little : we know that it often ejects 
 calcareous matter, and that the country all around 
 it is calcareous : but our information in regard to 
 ./Etna is more to the point. It has already been 
 mentioned, that on the sides of that mountain a 
 bed of sea shells has been discovered 2400 feet 
 above the sea. It is therefore incredible that its 
 whole bulk, or even that its whole surface, should 
 be of volcanic origin, since the ruins of a temple 
 built before our era, still stand on its side, unco- 
 vered by volcanic matter : and from the nature of 
 the masses composing the volcanic mountain 
 which fell in America, geologists are perfectly as- 
 sured that the mountain itself could not have 
 resulted from volcanic eruptions. 
 
 It has already been noticed, that no known vol- 
 cano is seated in granite, and that granite is not 
 to be seen near any volcano, except in very low 
 situations. The same may be said of primitive 
 rocks in general. One eruption of J2tna covered 
 a space of 50 leagues in circumference, and 12 
 feet in thickness, with calcareous sand ; and cal- 
 careous earth, though it forms a very large pro- 
 portion of secondary, enters very sparingly into 
 the composition of primitive rocks : so that some 
 geologists are not inclined to believe that volca- 
 noes are very deeply seated in the earth. 
 
 Where fire exists we naturally believe the ex- 
 istence of combustibles. The known combustion 
 of sulphur and iron filings, induced many to sup- 
 pose that volcanoes originate from the decomoo- 
 
174 
 
 sition of vast deposites of pyrites, which are com- 
 posed of iron and sulphur : but no spontaneous 
 inflammation of pyrites^ias ever been observed. 
 
 Werner has given his attention to the subject 
 of the probable origin of volcanoes ; and knowing 
 that coal has ignited spontaneously, and that there 
 are vast beds of this substance, of which that at 
 Liege in France, 90 feet thick, and 2 beds in Bo- 
 hemia, one of which has been worked 90 feet 
 deep, and the other much deeper, without reach- 
 ing the bottom, are instances ; he is inclined to 
 suppose, that to vast deposites of coal may be 
 attributed the origin of volcanoes. The conse- 
 quence of the spontaneous combustion of immense 
 beds of coal, would be the melting of the stony 
 beds that rest upon it. But the question arises, 
 whence the power of raising vast masses, and of 
 ejecting them, together with prodigious showers 
 of sand ? The answer follows : the expansion of 
 aqueous vapour, or steam ; and that water plen- 
 tifully flows from many volcanoes, particularly 
 those of America, we have already quoted suffi- 
 cient evidence. 
 
 Humboldt, who, it must be acknowledged, has 
 Lad ample opportunity for observing the pheno- 
 mena of volcanoes, seems to be of opinion that 
 certain of them are very deeply seated in the 
 earth. He says it is a remarkable fact, that the 
 volcanoes of Mexico are ranged in a line from 
 east to w,est, forming a parallel of great elevation. 
 In reflecting on this fact, and comparing it with 
 
175; 
 
 his observations upon certain phenomena attend- 
 ing Vesuvius, he is tempted to suppose that the 
 subterraneous fire has pierced through an enor- 
 mous crevice, which exists in the bowels of the 
 earth, between the latitudes of 18. 59. and 19. 
 12f, and stretches from the Pacific to the At- 
 lantic ocean. 
 
 From the' great differences in the theories of 
 these naturalists, we are necessarily led to a con- 
 clusion, that as yet we have no sufficient data to 
 enable us reasonably to account for the origin of 
 volcanoes. 
 
 OF THE DELUGE. 
 
 THE traditions recorded by many persons and 
 nations perfectly agree with the writings of Moses, 
 and with the researches of geologists, in regard to 
 the actual state of the surface of the globe, in this, 
 that it has suffered a great catastrophe by water. 
 It is alluded to by Berosus in the time of Alex- 
 ander ; by Plato ; by the Hindus ; who, according 
 to Sir William Jones, mention it in one of their 
 sacred books, orvedas, nearly in the same terms, 
 and refer it to nearly the same period as Moses ; 
 and in the records of the Chinese philosopher 
 Confucius, there is an allusion in the following 
 terms : t Having raised himself to heaven, Yao 
 bathed the feet even of the highest mountains, 
 covered the less elevated hills, and rendered the 
 plains impassable ;' allusions to the deluge arc 
 
176 
 
 also said to be involved in the astronomical cal- 
 culations of the Chaldeans. It is remarked by 
 Cuvier that mere chance could not give so striking 
 a resemblance between the traditions of the Assy- 
 rians, the Hindus, and the Chinese ; who more- 
 over attribute the origin of their respective mo- 
 narchies to the same period of about 4000 years 
 back. The ideas of these three nations, who have 
 so fevv features of resemblance, or rather, who are 
 so entirely dissimilar in language, religion, and 
 laws, could not have so exactly agreed on this 
 point, if it had not been founded in truth. Other 
 and remarkable traditional evidence may be ad- 
 duced. 
 
 Acosta, in his history of the Indies, says that 
 the Mexicans make particular mention of a deluge 
 by which all men were drowned ; and Dr. Watson, 
 in one of his sermons, records a reply given by an 
 inhabitant of Otaheite to one of our circum- 
 navigators, to a question regarding their origin : 
 that ' a long time ago, the earth was dragged 
 through the sea ; and their island, being broken ' 
 off, was preserved.' 
 
 ... If it be true, as stated by Don Ulloa, that, during 
 his travels in Peru, he found shells on a mountain 
 more than 1,4,000 feet above the level of the sea, 
 it affords a presumptive evidence that the sea 
 must have attained that elevation ; which is nearly 
 equal to two-thirds the height of the most elevated 
 points of land : and if it arose to so great a height, 
 there seems no reason for assuming that as the 
 
177 
 
 limit ; we may reasonably thence infer that it 
 covered the tops of the highest mountains. 
 
 There are, however, many circumstances relat- 
 ing to the lower parts of the earth, that afford in- 
 teresting evidence of the great catastrophe. The 
 compact argillaceous substance called shale,which 
 lies over the independent coal formation, is often 
 found to enclose vegetable remains ; and it is said 
 to exhibit, near Coalbrookedale, the impressions 
 of gigantic ferns and reeds peculiar to the Ame- 
 rican continent. Deposites of marine plants and 
 animals have been found in the interior of the 
 European and Asiatic continents, frequently in 
 considerable abundance. In Corsica are found 
 the remains of an animal exclusively belonging to 
 Siberia. In the year 1771 the carcase of a rhino- 
 ceros, an inhabitant of the torrid zone, was found 
 on the banks of the Vilhoui. The bones of the 
 mammoth, which is a species of the elephant, are 
 found in three of the four quarters of the globe ; 
 and those both of the, African and Asiatic ele- 
 phant, have been found in many places in Eng- 
 land : they occur likewise in Italy, France, Ger- 
 many, and Sweden. It is worthy of remark, that, 
 although in the two cited instances, the carcases 
 of the animals occurred- nearly whole, entire 
 skeletons are seldom found, but mostly separate 
 bones, widely dispersed : and it is said that be- 
 tween the countries now inhabited by these ani- 
 mals, and some of those in which their bones 
 have been discovered, there are chains of moun- 
 tains exceeding 9000 feet in elevation. 
 
178 
 
 All these circumstances seem to speak a lan- 
 guage so perfectly intelligible that it cannot be 
 misunderstood ; that since the creation of animals 
 the world has suffered by an universal inundation; 
 that * all the fountains of the great deep were 
 broken up, and the windows of heaven were 
 opened.' 
 
 The manner in which this deluge was accom- 
 plished, is a problem that has long occupied the 
 imaginations of philosophers and naturalists. 
 
 The question is this : since the tops of the highest 
 mountains, which are about four miles above the 
 present level of the sea, were covered with water; 
 whence could be derived a sufficient quantity to 
 surround, to the depth of four miles, a globe 
 25,000 miles in circumference. 
 
 It is evident that in order to accomplish this, 
 the rain of forty*days and nights was not sufficient; 
 for the context says that ' all the fountains of the 
 great deep were broken up.' 
 
 What precisely is meant by the great deep, and 
 where it was situated, still continues to be pro- 
 blematical. Attempts at its explanation have 
 caused the fabrication of at least fifty theories of 
 the earth, not one of which is satisfactory. 
 
 Some of these theories were briefly recounted 
 on a former evening, as being more or less con- 
 nected with the creation of the world. 
 
 Burnet imagined that before the deluge, the 
 earth was a mere crust, containing a vast abyss of 
 waters ; which issuing, deluged the earth, forming 
 mountains of the broken crust. 
 
179 
 
 Whiston supposed the deluge to have been 
 occasioned by a comet. But a bare recital of 
 hypotheses so gratuitous would scarcely be amus- 
 ing ; for in the general, there is so little agree- 
 ment between them and the known phenomena 
 of nature, as resulting from those laws which in 
 point of fact constitute nature, that they are no 
 longer deemed worthy of a place in a rational 
 mind. Other theorists, however, bent upon a 
 more reasonable philosophy, have looked into 
 nature for a solution of this interesting question. 
 
 Kirwan has assumed that, in addition to rain of 
 forty days and nights, a prodigious rising took 
 place in the waters of the great Southern Ocean, 
 which, he sets out with saying, is the greatest 
 collection of waters on the face of the globe; that 
 this ocean was the great deep mentioned by 
 Moses ; and he supposes that Noah resided on its 
 borders, for otherwise he could not have seen that 
 the great abyss was opened. He conceives that 
 these waters were impelled northwards, with re- 
 sistless impetuosity, against the continent which 
 at that time probably united Asia with America; 
 tearing up and sweeping away the whole of that 
 immense tract, with the exception of those islands 
 which still remain. 
 
 Here, then, is supposed a suspension of some of 
 the laws of nature, or how could so vast a body 
 of waters have arisen from its natural level, und 
 have torn up and swept away a wholf connecting 
 continent, by what Kirwan terms its resistless 
 
180 
 
 impetuosity. I do not propose to follow him 
 through all the ramifications of his theory, but 
 it may not be amiss to notice the apparent im- 
 possibility that the ark, or the little world within 
 it, could have sustained the horrible shocks that 
 must have been given to it by surges equal in 
 power, and frequent enough in repetition, to cause 
 the destruction of a continent. 
 
 Others have resorted to another theory. It is 
 known that there is at all times a passage of elec- 
 tric matter into the earth, or from the earth into 
 the atmosphere ; and it is presumed that the elec- 
 tric fluid contained in the atmosphefe,isthe agent 
 which suspends therein the water which rises from 
 the earth in vapour. 
 
 Now they suppose that natural causes were so 
 influenced for the sake of producing the deluge, 
 as that the air being divested of the electric fluid, 
 universal and amazing torrents of rain fell during 
 forty days and nights. And it is further supposed 
 that as the earth contained a double portion of 
 electric fluid, which experiment has proved to 
 possess the power of raising water upon and 
 above the earth, that the waters contained in its 
 fissures and caverns, and even whole oceans, were 
 thereby raised so far above their natural eleva- 
 tions, as to cover the tops of tli^ moun- 
 tains. 
 
 Thus has the sagacity of man (according to the 
 present extent of his knowledge 4 ) been brought 
 into action, in the endeavour to account for this 
 
181 
 
 wonderful phenomenon ; and we have seen that 
 even those who have attempted to explain it, in 
 some sort through the agency of natural causes, 
 have been compelled to call in aid of their theo- 
 ries, the miraculous intervention of the Great 
 Author of Nature. 
 
 OF THE INTERNAL STRUCTURE OF THE EARTH, 
 AND OF THE PROBABLE 'AGENT EMPLOYED IN 
 PRODUCING THAT STRUCTURE. 
 
 THE evidence produced on former evenings has 
 satisfactorily proved, as I trust, that the researches 
 of geologists have warranted them in making 
 three grand features in the division of the rocks 
 or masses which compose the crust of the globe. 
 
 PRIMITIVE ROCKS : 
 Consist only of crystalline defositcs ; 
 Contain no organic remains ; 
 Arc found below all other rocks ; 
 Rise from the base through the centre, and form 
 
 the summits of lofty mountains. 
 
 
 
 TRANSITION AND FL<ETZ ; 
 
 or 
 SECONDARY ROCKS : 
 
 Consist partly of crystalline, partly of mechanical 
 
 deposites; 
 Contain organic remains of shells ; some of than 
 
 not now found in the seas ; 
 Are never found under primitive rocks. 
 R 
 
182 
 
 ALLUVIAL DEPOSITES : 
 Consist of mechanical deposites ; 
 Result from the ruin of rocks ; 
 Contain the shells of fish now found in the ocean, 
 
 and the bones of large land animals ; 
 Are found above all other rocks. 
 
 Geologists, almost universally, have agreed upon 
 the nature and structure of the two latter descrip- 
 tions of rocks, and even upon the manner in which 
 they were deposited. For as almost all the 
 rocks denominated secondary, and those called 
 alluvial, contain the shells offish which once lived 
 in the sea ; all agree that these rocks must have 
 been formed since those fish lived ; and that, gen- 
 erally speaking, they were deposited by the sea. 
 
 But in the estimation of some, primitive rocks, 
 which are so termed chiefly because they contain 
 no organic remains, do not owe their origin to 
 the' same cause. For though all coincide in the 
 belief that the earth, to a certain depth, has once 
 been in a fluid state, of which its spheroidal 
 figure is considered to be a proof, yet opinions, as 
 to the nature of that fluid, are most completely at 
 variance ; inasmuch as one party considers it to 
 have been caused by the agency of /re, and the 
 other by that of water. 
 
 These two parties are termed voleanists and 
 neptunists ; or more familiarly by geologists, 
 Hitttonians and Wernerians ; because the late Dr. 
 Hutton of Edinburgh was the great champion for 
 
183 
 
 the agency of fire, and because Werner, now re- 
 siding in Germany, espouses the opposite theory. 
 
 Dr. Hutton seemed to consider that the great 
 question we have to decide, is, how our vast con- 
 tinents have been raised so high above the level of 
 the sea. Arguing from certain chemical facts, 
 which it is not my province to explain, Dr. Hutton 
 thought himself justified in supposing that the 
 older rocks, as granite and the rest, were formed 
 from a mass in a state of fusion by fire : that, owing 
 to the intensity of this fire, and the expansion 
 consequent to that intensity, in the central parts 
 of the earth, all those rocks which are termed 
 primitive, on which all others rest, and which 
 form, as it were, the rough frame-work of the 
 earth, were raised up, forming continents and 
 islands. He moreover supposed, that, in cooling, 
 these vast masses suffered contractions, producing 
 rents and fissures in them, which afterwards were 
 filled from the central fire, with metallic and othes 
 substances; constituting what are now known by 
 the name of mineral veins. 
 
 Contemplating the causes of destruction perpe- 
 tually operating, as volcanoes, exposure to rains 
 and air, and sea-floods, Dr. Hutton also imagined 
 that these, by the destruction they cause, and the 
 quantity of ruin they carry from the land, are 
 perpetually laying, in the unfathomable regions 
 of the sea, the foundations of new continents ; 
 which, gradually rising, will in turn destroy those 
 now existing. 
 
 
184 
 
 Dr. Hutton does not suppose the earth, as it 
 MOW is, to have been an original creation ; but 
 that it has resulted from the ruin of other and 
 former worlds : of which he emphatically says, 
 * we can find no vestige of a beginning, no pros- 
 pect of an end.' 
 
 Werner, on the contrary, does not seem to con- 
 sider that the great question we have to decide 
 is, how our vast continents have been raised so 
 high above the sea. 
 
 He considers primitive rocks to be precisely in 
 the situation in which they were first deposited ; 
 and as these rocks are all crystalline, or composed 
 of vast aggregations of crystals, that the sub- 
 stances of which these crystals are composed, 
 being held in solution in a vast body of water, 
 greater in elevation than the summits of our high- 
 est mountains, followed the laws of affinity, and 
 were deposited, forming those masses termed 
 primitive rocks : 
 
 That these rocks, during their consolidation, 
 split, forming rents and fissures; that these fissures 
 were filled from the ocean with mineral bodies, 
 and are what we now term mineral veins. 
 
 Such are the outlines of the two theories which 
 now divide the opinions of geologists. Upon their 
 comparative merits, it will not perhaps become 
 me to say much. Yet, although no opportunity 
 has hitherto occurred, or perhaps ever will occur, 
 for my examination of geological facts on a large 
 scale, I atn unwilling to leave the subject with- 
 out expressing some opinion. 
 
185 
 
 It may be true that the chemical facts on which 
 they rely who espouse the theory of the agency of 
 fire, may not have been altogether controvert- 
 ed 5 and that these facts may apply, by possibility, 
 to the formation of certain rocks : but arguing gen- 
 erally, from what is known of the nature of fire 
 and of fuel, from what may be learned by the ex- 
 amination-of hand specimens, and from the results 
 obtained by the application of chemical agency 
 to their component parts, I find it impossible 
 "iot to give a preference to that theory which as- 
 scribes the formation of primitive rocks to the 
 agency of water. It appears to me, tha$ an oppo- 
 sition to the agency of fire may reasonably be 
 supported by certain phenomena presented to us 
 by the component substances of granite and 
 gneiss, the two oldest of the primitive rocks, which 
 are, for the most part, compounded of regular 
 crystals of quartz, felspar, and mica, irregular!) 7 ' 
 disposed in so far as regards each other. 
 
 If we could once arrive at any certainty that a 
 -jingle crystal of either of these substances had, in 
 any case, been formed through the agency of 
 either fire or water, it would seem to form rea- 
 sonable ground for attributing the whole to the 
 *arne agency. If, for instance, we could show that 
 u crystal of quartz had been formed in water, it- 
 would go near to determine the quf-slion ; because 
 as the crystals of quartz, felspar, and mica, rggre.- 
 gately forming granite, are irregularly disposed 
 ,viih regard to each ether; and as the crystals of 
 R 2 
 
quartz sometimes enclose lesser crystals of fel- 
 spar or of mica, it seems clearthat the same agency 
 must be referable for the production of the whole. 
 
 Now it has been already quoted that professor 
 Seigling discovered some crystals of quartz that 
 were deposited from an aqueous solution in which 
 silex predominated, termed the liquor of flints, 
 and which had accidentally been left eight years 
 unobserved : these crystals were hard enough to 
 give fire by the steel. It is asserted that Bergman 
 also obtained crystals of the same substance from 
 an aqueous solution containing silex.* 
 
 These facts may not be deemed conclusive of 
 the question ; but we have, as it seems to me, 
 strong corroborative evidence in addition. 
 
 Crystals of quartz are by no means uncommon, 
 in which are enclosed both water and air. I pos- 
 sess two or three such specimens, as well as ano- 
 ther, enclosing, together with water and air, a 
 minute portion of a dark substance that seems to 
 be bitumen ; which, turn the crystal any way, al- 
 ways presents itself in the air, and swimming on 
 the water. 
 
 Now if, in the production of these crystals, fire 
 liad been the agent, would not the water have 
 passed off in the form of vapour, and the bitumen 
 have been consumed ? It seems impossible to 
 suppose these crystals to have been formed by 
 any other agency than that of water. 
 
 * See Note, page 109: see also Nicholson's Journal, vol, i, page 21 7. 
 *f r mrto edition, 
 
187 
 
 Other facts are worth observing. If a crystal of 
 quartz be exposed to a red heat, it loses its bril- 
 liancy, together with about three parts in the hun- 
 dred of its weight, and is no longer transparent. 
 This loss, it should seem, can be no other than the 
 loss of water taken up during crystallization. 
 The same holds, in part, with respect to felspar ; 
 which, though it never is transparent, loses from 
 two to forty parts in the hundred of its weight, 
 when exposed to the same heat. 
 
 Facts so pointed and important in regard to two 
 of the three substances composing the oldest of 
 the primitive rocks, seem to furnish strong evi- 
 dence, that in the reducing into their present state 
 the substances composing the great masses which 
 form the crust of the globe, water was the agent. 
 
 WE have now completed the object we had in 
 view, in dedicating five evenings to the investi- 
 gation of simple and compound mineral bodies ; 
 namely, an outline of the great masses composing 
 the crust of the globe ; of their arrangement ; and 
 of their component substances. 
 
 In this view I have as much as possible studied 
 brevity. It may be well imagined that there are 
 many facts, considerations, and inquiries, of which 
 nothing has been said; facts in regard to the 
 relative natures and positions of compound mine- 
 ral bodies and masses ; considerations and inqui- 
 ries into which those facts would necessarily lead. 
 
188 
 
 Enough, however, I trust, has been said to show 
 that geologists have truth for their object. That 
 faculty of genius which consists in invention no 
 longer presides ; the theories which attributed 
 the origin of the globe to a portion of the sun 
 struck off by a comet, and fifty others equally 
 absurd, which by their splendour once dazzled 
 mankind, are gone by and neglected. Patient and 
 profound investigation has taken their place ; pro 
 ducing research nearly to the summits of our most 
 elevated mountains, and to the greatest depths 
 to which the miner can descend. 
 
 But since it is computed that all our researches 
 cannot extend further into our earth, than, by 
 comparison, the thickness of the paper which 
 covers a globe of three feet in diameter, is to that 
 globe ; it will follow that we cannot possess any 
 knowledge of what the central parts of the earth 
 are actually constituted. 
 
 We have, however, the most indubitable evi- 
 dence that the crust of the globe has been subject 
 to revolutions, both partial and general. We are 
 assured by the numerous facts that have been 
 quoted, and by far more numerous -.vincli yet 
 remain, that the sea must have changed both its 
 place and its height. Proofs have been adduced 
 that animal life has repeatedly and largely fallen 
 the victim t > these terrible events ; there seems 
 reason to conclude that some animal! have been 
 dest -- sudden inundations; that others 
 
 lriv<- laid drv in conseouenrp of the bottoms 
 
 o. the sea being suddenly elevated ; and that these 
 
189 
 
 calamities have caused great changes in the outer 
 crust of the globe. It seems also clear, that since 
 these first and greater commotions, those which 
 followed, uniformly acted at a less depth and less 
 generally* We have seen that the researches of 
 geologists have ascertained that of those animated 
 beings, of which the remains are inclosed in those 
 rocks which immediately rest upon primitive rocks, 
 the races have become extinct ; that the newer rocks 
 contain the remains of animals more nearly op- 
 Broaching to, but not absolutely of the same species 
 as those inhabiting our present seas; but that the 
 newest contain only the remains of such animals as 
 now exist in the seas, together with the bones of large 
 land and amphibious animals. 
 
 Every part of the globe distinctly bears the 
 impress of these great and terrible events. The 
 appearances of change and ruin are stamped on 
 every feature. Change and ruin by which not a 
 particle of the creation has been lost, but which 
 have been repeated, and are distinctly marked by 
 the genera and species of the organic remains they 
 enclose. 
 
 Thus, those fossils and petrifactions which 
 heretofore were carefully collected as curiosities, 
 now possess a value greater than as mere curiosi- 
 ties. They are to the globe what coins are to 
 the history of its inhabitants ; they denote the 
 period of revolution ; the*; ascertain at least com- 
 parative dates. 
 
 If the inquiry should arise, What benefit has 
 resulted from ruin so extensive and so general ? 
 
190 
 
 the answer is obvious; soil and fertility. If for a 
 moment we imagine a world composed only of 
 those rocks which we call primitive, which bear 
 no marks of ruin, enclose no organic remains ; 
 we know from the nature of their component 
 substances, that their exposure to the action of 
 the elements during veiy many ages, would 
 scarcely so separate and disintegrate them, as to 
 produce a ioil capable of any considerable vege- 
 tation ; in other words, would fit the earth to 
 receive and to maintain an extensive and almost 
 universal population. A large and fertile part of 
 England is composed of the ruin of rocks to a 
 considerable depth ; and this greatly obtains in 
 all the most level and most fertile countries. Are 
 we not then in degree justii^ed in assuming, that 
 this great ruin was designed to fit and prepare 
 the earth for the support of the numerous animal 
 tribes that inhabit it ; most especially for MAN ; 
 who, doubtless, from his superior intellectual en- 
 dowments, has emphatically been termed ' the 
 Lord of the Creation.' 
 
 But our inquiries into utility need not stop here. 
 All our researches have evinced such unquestion- 
 able proofs of design and contrivance, that it is 
 impossible not to see them ; and if we see them, 
 it is or ought to be equally impossible not to 
 ascribe them to the great Artificer of the universe. 
 This, indeed, is the reasonable end and aim of all 
 our inquiries, and all our philosophizing. 
 
 Without mountains, what in all probability 
 would be the earth? A swamp or a sandy desert ; 
 
m 
 
 and the atmosphere a receptacle of noisome and 
 pestilential exhalation. As conductors of the 
 electric fluid, mountains contribute to the pro- 
 duction of rain, which fertilizes the earth and 
 purifies the atmosphere. They are the principal 
 repositories of metallic ores. Their benefits, 
 therefore, are great and extensive. 
 
 . Hitherto the labours of the chemist have dis- 
 covered 27 metals, 9 earths, 2 fixed alkalies, and 
 the two bases of combustible bodies, sulphur and 
 carbon : and these (although some of them may 
 possess some characters in common) have each 
 some peculiar to themselves, and are, therefore, 
 termed elementary substances. It may be remark- 
 ed that these, either in the simple or compound 
 
 state, are found in quantity admirably apportioned 
 to their utility ; and, in the same proportion, with 
 whatsoever they maybe combined, they are gene* 
 rally most readily and easily freed from those 
 substances with which they are compounded. Is 
 it possible for one moment to doubt whether all 
 this exhibits design and contrivance for the benefit 
 of Man? 
 
 But further ; is not design manifest in regard 
 to the depositions of salt and of coal, so essential 
 to man ? Suppose these to have taken place be- 
 tween the earlier rocks, or in the masses of primi- 
 tive mountains, or any where except where we 
 find them ; that is, just beneath the surface : they 
 would in that case have been nearly lost to man. 
 Can we appreciate their present benefits ? Can 
 
192 
 
 we doubt that there was design in placing them 
 where we find them ? 
 
 But, in speaking of soil and fertility as the con- 
 sequence of the decay and ruin every where to be 
 observed, I omitted one important consideration ; 
 namely, the decay of vegetables, which so essen- 
 tially contributes to fertility, as principally com- 
 posing what we call mould. But there is one 
 exception to the general rule in regard to the de- 
 cay of vegetable matter, not sufficiently noticed, 
 as being an exception in the favour of Man ; but 
 which demands a thought. The leaf, after it has 
 fallen, enriches our soil ; the gardener esteems it 
 an excellent manure ; but the tree that bore the 
 leaf, when deprived of life, decays not until after 
 a long period of time ; not until it has long been 
 in the service of Man. Without wood, how 
 should we be able to accomplish the many pur- 
 poses to which it is turned ? Where could we 
 find a substitute . ? 
 
 This, I grant, is a digression ; but it is almost 
 the only one I have allowed myself. I shall 
 perhaps be excused, when it is considered, that it 
 is adding another proof, in itself rather too ob- 
 vious to attract much notice, to the many already 
 adduced, that design and contrivance are every 
 where manifest, and in every thing intended for 
 the advantage of Man. 
 
 THE END. 
 
7 DAY USF 
 
t 
 
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