THE LIBRARY 
 
 OF 
 
 THE UNIVERSITY 
 
 OF CALIFORNIA 
 
 DAVIS 
 
The 
 
 Founders of Geology 
 
 By 
 Sir Archibald Geikie, F.R.S. 
 
 D.C.L.Oxf. ; D.Sc. Camb., Dubl. ; LL.D. Edin., Glasg., St. And. 
 Corr. Instit. France; Acad. Berlin, Vienna, Munich, Turin, Lincei, Rome, 
 Gottingen, Stockholm, Christiania, Belgium, Philadelphia, - 
 
 Boston ; Nat. Acad. Washington, etc. 
 Late Director-General of the Geological Survey of Great Britain and Ireland 
 
 Second Edition 
 
 London 
 Macmillan and Co., Limited 
 
 New York : The Macmillan Company 
 1905 
 
 A II rights reserved 
 
First Edition (Extra Crown 8vo) 1897. 
 Second Edition, 8vo 1905. 
 
 GLASGOW : PRINTED AT THE UNIVERSITY PRESS 
 BY ROBERT MACLEHOSE AND CO. LTD. 
 
PREFACE 
 
 IN the year 1896 the President of the Johns Hopkins 
 University, Baltimore, invited me to inaugurate the 
 Lectureship founded in that seminary by Mrs. George 
 Huntington Williams in memory of her husband, the 
 distinguished and widely regretted Professor of Geology 
 there. In accepting this invitation I chose for my 
 subject an outline of the history and development of 
 Geology during the period between the middle of the 
 eighteenth and the close of the second decade of the 
 nineteenth century an interval of about seventy years, 
 full of peculiar interest to students of the science, for 
 it was during that interval that the main foundations 
 of modern geology were laid. 
 
 In making this choice I was influenced by my 
 experience of the limited acquaintance with the his- 
 torical development of the science which has often 
 been shown even by those who have done good service 
 in enlarging its boundaries. English-speaking geo- 
 logists have for the most part contented themselves 
 with the excellent, but necessarily brief, summary of the 
 subject given by Lyell in the introductory chapters of 
 his classic Principles^ no fuller digest of geological 
 history having been published in their language. It 
 appeared to me that it might be useful to recount 
 
vi Preface 
 
 the story of a few of the great pioneers during the 
 momentous period which I wished to select, and to 
 show, from their struggles, their failures, and their 
 successes, how geological ideas and theories arose, and 
 were step by step worked out into the forms which 
 they now wear. 
 
 The narrative thus proposed was made the subject of 
 six lectures which were published in the summer of 
 1897 as a small volume entitled The Founders of Geo- 
 logy. This work has been for some time out of print. 
 In preparing a new edition 1 have departed from the 
 original form of lectures, and from the restricted treat- 
 ment of the subject which a short course of lectures 
 necessarily involved. While retaining and also enlarg- 
 ing the more detailed discussion of the remarkable 
 period embraced in the original lectures, I have given a 
 sketch of the earlier progress of geological ideas, from 
 the times of ancient Greece onwards to the epoch that 
 formed the starting point of my former volume. 
 
 In this extension of the subject I have adhered to my 
 original plan of tracing the origin and slow develop- 
 ment of geological science, rather in an account of the 
 careers of a few of the chief leaders by whom the 
 progress has been mainly effected, than in an attempt 
 to summarise also the work of their less illustrious 
 contemporaries. 
 
 Since the publication of the first edition, my lamented 
 friend the late Professor Zittel of Munich published 
 (1899) his Geschichte der Geologic und Paldontologie a 
 work of extraordinary labour, fullness and accuracy, 
 with which no student of geology who cares to know 
 the history of his science can dispense. An excellent 
 
Preface vii 
 
 abridged English translation of this voluminous treatise 
 has been prepared by Mrs. Ogilvie Gordon. The 
 scheme of treatment adopted by Professor Zittel, 
 however, differs so much from that which I have 
 followed that our two volumes may be regarded as 
 in large measure supplementary to each other. While 
 he has noted the contributions of all who have in any 
 important way advanced general or local geology, I 
 have selected for fuller consideration chiefly the lives 
 and work of some of the masters to whom we mainly 
 owe the foundation and development of geological 
 science. 
 
 November, 1905. 
 
CONTENTS 
 
 CHAPTER I 
 
 Introduction. Geological ideas among the Greeks and Romans in 
 regard to (i) Underground forces ; (ii) Processes at work on the 
 surface of the earth ; (iii) Proofs of geological changes in the 
 Past, pp. 1-41 
 
 CHAPTER II 
 
 Growth of geological ideas in the Middle Ages Avicenna and the 
 Arabs. Baneful influence of theological dogma. Controversy 
 regarding the nature of Fossil Organic Remains. Early observers 
 
 ^ in Italy Leonardo da Vinci, Falloppio, Steno, Moro. The 
 English cosmogonists Burnet, Whiston, Woodward. Robert 
 Hooke, John Ray, Martin Lister, Robert Plot, Edward 
 Lhuyd, - pp. 42-78^ 
 
 CHAPTER III 
 
 Scientific Cosmogonists Descartes, Leibnitz. Speculations of De 
 Maillet and Buffon. Early illustrated works on fossil plants and 
 animals Lang, Scheuchzer, Knorr, Walch, Beringer, pp. 79-103 
 
 CHAPTER IV 
 
 The Rise of Geology in France Palissy. The labours of 
 Guettard, - pp. 104-139 
 
 CHAPTER V 
 
 The Foundation of Volcanic Geology Desmarest, - pp. 140-175. 
 
x Contents 
 
 CHAPTER VI 
 The Rise of Geological Travel Pallas, De Saussure, - pp. 176-191 
 
 CHAPTER VII 
 
 History of the Doctrine of Geological Succession Arduino, 
 Lehmann, Fiichsel, Werner, - - pp. 192-236 
 
 CHAPTER VIII 
 
 The Wernerian School of Geology Its great initial influence and 
 
 subsequent decline. Effect of the controversy about the origin 
 
 of Basalt upon this School. Early history of Volcanic Geology. 
 
 " History of opinion regarding Earthquakes, - - pp. 237279 
 
 CHAPTER IX 
 
 The Rise of the modern conception of the theory of the Earth 
 Hutton, Playfair, - pp. 280-316 
 
 CHAPTER X 
 
 Birth of Experimental Geology Sir James Hall. Decay of 
 Wernerianism, - pp. 317-332 
 
 CHAPTER XI 
 
 The Rise of Stratigraphical Geology and of Palaeontology in France 
 Giraud-Soulavie, Lamarck, Cuvier, Brongniart, and Omalius 
 d'Halloy, pp. 333~377 
 
 CHAPTER XII 
 
 The Rise of Stratigraphical Geology in England Michell, White- 
 hurst, William Smith, Thomas Webster, the Geological 
 Society of London, W. H. Fitton. Early teachers and text- 
 books. Influence of Lyell, - - pp. 378405 
 
CHAPTER I 
 
 INTRODUCTION. Geological ideas among the Greeks and Romans in 
 regard to (i) Underground forces ; (ii) Processes at work on the 
 surface of the earth ; (iii) Proofs of geological changes in the 
 Past. 
 
 IN science, as in all other departments of inquiry, no 
 thorough grasp of a subject can be gained, unless 
 the history of its development is clearly appreciated. 
 Nevertheless, students of Nature, while eagerly press- 
 ing forward in the search after her secrets, are apt 
 to keep the eye too constantly fixed on the way that 
 has to be travelled, and to lose sight and remembrance 
 of the paths already trodden. It is eminently useful, 
 however, if they will now and then pause in the race, in 
 order to look backward over the ground that has been 
 traversed, to mark the errors as well as the successes of 
 the journey, to note the hindrances and the helps which 
 they and their predecessors have encountered, and to 
 realise what have been the influences that have more 
 especially tended to retard or quicken the progress of 
 research. 
 
 Such a review is an eminently human and instructive 
 exercise. Bringing the lives and deeds of our fore- 
 runners vividly before us, it imparts even to the most 
 
2 Introduction 
 
 abstruse and technical subjects much of the personal 
 charm which contact with strenuous, patient, and 
 enthusiastic natures never fails to reveal. Moreover, 
 it has a double value in its bearing on the progress 
 of those who are engaged in original research. A 
 retrospect of this kind leads to a clearer realisation 
 of the precise position at which they have arrived, 
 and a wider conception of the extent and limits of 
 the domain of knowledge which has been acquired. 
 On the other hand, by enabling them to comprehend 
 how, foot by foot, the realms of science have been 
 painfully conquered, it furnishes suggestive lessons as 
 to tracks that should be avoided, and fields that may 
 be hopefully entered. 
 
 In no department of natural knowledge is the 
 adoption of this historical method more necessary 
 and useful than it is in Geology. The subjects with 
 which that branch of science deals are, for the most 
 part, not susceptible of mathematical treatment. The 
 conclusions formed in regard to them, being often 
 necessarily incapable of rigid demonstration, must 
 'rest on a balance of probabilities. There is thus 
 room for some difference of opinion both as to facts 
 and the interpretation of them. Deductions and 
 inferences which are generally accepted in one age 
 may be rejected in the next. This element of 
 uncertainty has tended to encourage speculation. 
 Moreover, the subjects of investigation are them- 
 selves often calculated powerfully to excite the 
 imagination. The story of this Earth since it became 
 a habitable globe, the evolution of its continents, 
 birth and degradation of its mountains, the mar- 
 
Introduction 3 
 
 vellous procession of plants and animals which, since 
 the beginning of -time, has passed over its surface, 
 these and a thousand cognate themes with which 
 geology deals, have attracted numbers of readers and 
 workers to its pale, have kindled much general interest, 
 and awakened not a little enthusiasm. But the records 
 from which the chronicle of events must be compiled 
 are sadly deficient and fragmentary. The deductions 
 which they suggest ought frequently to be held in 
 suspense from want of evidence. Yet with a certain - 
 class of minds, fancy comes in to supply the place 
 of facts that fail. And thus geology has been- 
 encumbered with many hypotheses and theories 
 which, plausible as they might seem at the time of 
 their promulgation, have one by one been dissipated 
 before the advance of fuller and more accurate know- 
 ledge. Yet before their overthrow, it may often be 
 hard to separate the actual ascertained core of fact 
 within them from the mass of erroneous interpreta- 
 tion and unfounded inference that forms most of 
 their substance. 
 
 From the beginning of its growth, geology has 
 undoubtedly suffered from this tendency to specula- 
 tion beyond the sober limits of experience. Its culti- 
 vators have been often described as mere theorists. 
 And yet in spite of these defects, the science has 
 made gigantic strides during the last hundred years, 
 and has gradually accumulated a body of well-ascer- 
 tained knowledge regarding the structure and history 
 of the earth. Few more interesting records of human 
 endeavour and achievement can be found than that 
 presented by the advance of this science. Little 
 
4 Introduction 
 
 more than a century ago geology had no generally 
 acknowledged name and place in the circle of human 
 studies. At the present day it can boast a voluminous 
 literature, hundreds of associations all over the world 
 dedicated to its cultivation, and a state organization 
 in almost every civilized country for its systematic 
 prosecution. I propose to trace some of the leading 
 steps in this magnificent progress. Even speculations 
 that have been thrown aside, and theories that have 
 been long forgotten, may be found to have been 
 not without their use in promoting the general 
 advance. 
 
 If all history is only an amplification of biography, 
 the history of science may be most instructively read in 
 the life and work of the men by whom the realms of 
 Nature have been successively won. I shall therefore 
 dwell on the individual achievements of a few great 
 leaders in the onward march of geology, and indicate 
 how each of them has influenced the development of 
 the science. At the same time I shall trace the rise and 
 progress of some of the leading principles of the science, 
 which, though now familiar as household words, are 
 seldom studied in regard to their historical develop- 
 ment. Thus, partly in the life-work of the men, and 
 partly in the growth of the ideas which they promul- 
 gated, we shall be able to realise by what successive 
 steps geological science has been elaborated. 
 
 The subject which I have chosen, if treated as fully 
 as it might fitly be, would require a full course of 
 lectures or more than one printed volume. Within 
 the limits which I have prescribed to myself, I can only 
 attempt to present an outline of it. Instead of trying 
 
Introduction 
 
 5 
 
 to summarize the whole history of geology, I think it 
 will be more interesting and profitable to pass somewhat 
 briefly over ancient and medieval time during which 
 geological ideas were crudely taking shape ; to dwell 
 rather fully on the labours of a few of the early masters, 
 who, by actual observation of nature and deduction 
 therefrom, laid the broad foundations of the science, to 
 touch only lightly on the work of some of their less 
 illustrious contemporaries, and to do little more than 
 allude to the modern magnates whose life and work are 
 generally familiar. I have accordingly selected for 
 fullest treatment, in this volume, what has been called 
 the Heroic Age of geology, or the period which extends 
 from the middle of the eighteenth to the earlier decades 
 of the nineteenth century, an interval of about seventy 
 years. A few later conspicuous names will require 
 some brief notice in order to fill up the general outlines 
 of our picture. 
 
 The most casual observation is now-a-days sufficient 
 to convince us that the surface of the earth has not 
 always been as it is to-day. At one place sheets of 
 sand and gravel point to the former presence of running 
 water, where none is now to be seen. Elsewhere shells 
 and other marine organisms underneath the soil show 
 that the dry land was formerly the bed of the sea. 
 Masses of sandstone, conglomerate and limestone, once 
 evidently laid down in horizontal layers on the sea- 
 bottom, but now hardened into stone, disrupted, placed 
 on end, and piled up into huge hills and mountain- 
 ranges, prove beyond all question to our modern eyes 
 that stupendous disturbances attended the conversion 
 of the sea-floor into land. 
 
6 Introduction 
 
 A few of the simpler and more striking of these 
 features might attract notice even among the earliest 
 and rudest tribes. But still more would the elemental 
 forces of nature arouse the fears, excite the imagination 
 and stimulate the curiosity of primitive man. Wind 
 and lightning, rain-storms and river-floods, breakers 
 and tidal waves, earthquakes and volcanoes would seem 
 ,\> be direct and visible manifestations of powerful but 
 " unseen supernatural beings. Nor would the more 
 obtrusive features of landscape fail to add their 
 influence mountains with their clouds, tempests and 
 landslips ; crags and precipices with their strange 
 grotesque half-human shapes, ravines with their gloomy 
 cliffs and yawning chasms between. 
 
 It is not difficult to conceive how from these con- 
 - current materials there would spring fables, legends and 
 myths, long before the spirit of scientific observation 
 and deduction was developed, and how such fables might 
 continue to satisfy the popular imagination long after 
 that spirit had arisen among the more reflective few. 
 The earliest efforts at the interpretation of nature found 
 their expression in the mythologies and cosmogonies 
 of primitive peoples, which varied in type from country 
 to country, according to the climate and other physical 
 conditions under which they had their birth. Geo- 
 logical speculation may thus be said to be traceable 
 in the mental conceptions of the remotest pre-scientific 
 ages. 
 
 The popular beliefs continued for a time to influence, 
 in a greater or less degree, the speculations of the 
 philosophers who began to observe the operation of 
 natural processes and who, though their deductions 
 
Geology of Greeks and Romans 7 
 
 were often about as unscientific as the myths for which 
 they were substituted, may yet be claimed as the 
 earliest pioneers of geology. The first stages of 
 advance in theoretical opinions on these subjects may 
 best be illustrated by a brief survey of the geological 
 ideas to be found scattered through the literature of 
 Greece and Rome. 
 
 Among the poets allusions abound to the popular 
 interpretations of geological phenomena, wherein the 
 influence of gods and heroes in altering the face of 
 Nature became the subject of legend and myth. It 
 is interesting to note the progress of the decay of 
 these ancient superstitions and their replacement by 
 more natural explanations, based upon actual obser- 
 vation of the present order of things. As an example 
 of this transition, reference may be made to the various 
 attempts to account for the remarkable defile of Tempe, 
 which was one of the marvels in the scenery of Greece. 
 The wide mountain-girdled plain of Thessaly was 
 popularly believed to have once been covered with 
 a lake which was ultimately drained by the kindly 
 intervention of Poseidon, who himself split open the 
 gorge in the encircling rocky barrier, whereby a passage 
 was given for the escape of the stagnant waters to 
 the sea. Later generations attributed the friendly act 
 to Hercules. By the time of Herodotus, however, 
 (B.C. 500) the supernatural had given way, in the minds 
 of reflective men, to a natural interpretation* of such 
 features. Yet the Father of History, as was natural 
 to his pious and reverential spirit, does not scornfully 
 reject the long established belief. " That the gorge 
 of Tempe, 7 ' he says, " was caused by Poseidon is 
 
8 Strabds Scepticism 
 
 probable ; at least one who attributes earthquakes and 
 chasms to that god would say that this gorge was 
 his work. It seemed to me to be quite evident that 
 the mountains had there been torn asunder by an 
 earthquake." l 
 
 By the beginning of our era, supernatural inter- 
 pretations of geological features had still further gone 
 out of fashion among the writers of the day, and it- 
 was now thought unnecessary even to allude to them. 
 Strabo (B.C. 54 A.D. 25) simply refers the Vale of 
 Tempe to the effects of an earthquake, as if its origin 
 were so manifest as to offer no reasonable ground 
 for any doubt. In no respect do the writings of this 
 geographer differ more conspicuously from those of 
 Herodotus than in their attitude towards the myths 
 of the olden time. The difference no doubt marks 
 the general progress of public opinion on the subject 
 in the course of five centuries. Strabo usually passes 
 over the legends in silence, and when he takes occasion 
 to refer to them, it is not infrequently to reject them 
 with contempt. He will not believe the story that 
 the River Alpheus flows under the sea and rises again 
 to the surface as the fountain of Arethusa at Syracuse, 
 and the reasons which he gives for his refusal are such 
 as a modern man of science might use. 2 Referring 
 to a statue at Siris, in Southern Italy, which was alleged 
 to have been brought from Troy after the siege and 
 to have closed its eyes when certain suppliants were 
 forcibly dragged away from its shrine, he sarcastically 
 remarks that some amount of courage is required to 
 believe this tale, and also to admit that so many statues 
 1 Book vii. 129. 2 vi, ii. 4. 
 
The Mediterranean Basin 9 
 
 could have been brought from Troy as were so 
 reputed. 1 He states that while at the Memnonium 
 at daybreak, he certainly heard a noise, but whether 
 it came from the statue or was made by some of the 
 company, he could not tell, though he was disposed 
 to believe anything rather than that stones themselves 
 emit sound. 2 He even carries this critical spirit into 
 his account of alleged historical events, as where, in 
 ridiculing the statement that the Cimbri were driven 
 out of their territory by an extraordinarily high tide, 
 he appeals to the known regularity and periodicity 
 of the tides, as a natural, harmless and universal 
 phenomenon, which disproves such tales. 3 
 
 In considering the opinions of the Greeks and 
 Romans relative to the origin of the various features 
 of the external world, it is well to note that the nations 
 gathered together in the vast basin that drains into 
 the Mediterranean Sea were placed in an exceptionally 
 favourable position for having their attention drawn 
 to some of these features. In particular, this region 
 displays with remarkable fullness the operation of 
 various natural agencies whereby the surface of the 
 earth is altered. It reveals also in a striking manner 
 to the observant eye proofs that these agencies have 
 been at work from a remote antiquity, and have in the 
 course of ages profoundly modified the distribution of 
 sea and land. Thus the countries situated within its 
 borders have been and still are subject to continual 
 shocks of earthquake. For many thousands of years 
 probably not a month has passed without a concussion 
 in some part of the region, usually slight enough to 
 1 vi. i. 14. 2 xvn. i. 46. 3 vii. ii. I. 
 
io The Mediterranean Basin 
 
 alarm without doing much damage, but ever and anon 
 as appalling calamities that have prostrated cities and 
 destroyed thousands of their inhabitants. Moreover 
 another phase of subterranean energy has from time 
 immemorial been conspicuously developed in the same 
 region. Two distinct and widely separated volcanic 
 centres exist in the Mediterranean basin, and have had 
 their eruptions chronicled by poets and historians from 
 a remote antiquity. One of these centres lies in the 
 Aegean Sea, where the isle of Santorin still remains an 
 active volcano. The other and much the more im- 
 portant area extends from the Phlegraean Fields around 
 Naples to beyond the southern coast of Sicily, and 
 includes the great cones of Etna and Vesuvius, besides 
 other smaller but active vents. From the dawn of 
 history the inhabitants of Greece and Italy have wit- 
 nessed the awe-inspiring eruptions of these volcanoes 
 which notably coloured some parts of the old myth- 
 ology. 
 
 Again, the Mediterranean region contains within its 
 limits a remarkable diversity of climates, and con- 
 sequently a varied and abundant development of all 
 those geological processes over which climate exerts a 
 controlling influence. The mountain chains, from the 
 ^ifar Pyrenees on the one hand to the distant Caucasus 
 on the other, with their snow-fields and glaciers, their 
 cloud-caps and storms, display the extremes of winter 
 cold, and of rainfall, tempests and landslips. On the 
 southern side of the basin lie wide tracts of country 
 with little or no rain, and passing inland into vast 
 sandy deserts of almost tropical heat. From the 
 mountains innumerable torrents gather into lakes and 
 
The Mediterranean Basin 1 1 
 
 rivers, which water the plains and bear the drainage 
 out to sea. Drought and inundation succeed each 
 other, and the same river which at one time carries 
 fertility all over its valley, at another time, swollen 
 into an impetuous flood, spreads across the plains, 
 sweeping away farms and villages, and burying the 
 soil under sheets of sterile gravel and sand. The 
 operations of such streams as the Rhone, the Po, 
 the Tiber, the Danube, the Achelous and the Peneius 
 were not only watched by the inhabitants along their 
 banks but became the subjects first, of widely diffused 
 legendary tales, and afterwards of philosophical dis- 
 cussion. On the south side of the great sea, the 
 Nile, with its mysterious sources and its unfailing / 
 annual rise, furnished an inexhaustible source of wonder J 
 and speculation. 
 
 Further, all round the basin of the Mediterranean 
 the younger geological formations, upraised from the 
 sea, now underlie many of the plains and rise high 
 along the flanks of the hills. In these deposits, shells 
 and other remains of sea-creatures have been preserved 
 in such vast numbers as could not fail to arrest atten- 
 tion even in the infancy of mankind. Since the 
 organisms are obviously like those still living in the 
 neighbouring sea, the inference could readily be 
 drawn that the sea had once covered the tracts of 
 land where these remains had been left. This con- 
 clusion was reached by some of the earliest Greek 
 philosophers, and there can be little doubt that it 
 led to those wide views of the vicissitudes of Nature 
 which were adopted in later centuries by their 
 successors. 
 
12 Aristotles Views of the Universe 
 
 Our retrospect of the growth of an intelligent 
 appreciation of the geological phenomena so well 
 developed in this long inhabited region need not 
 take us further back than the time of Aristotle, the 
 true Father of Natural History, (B.C. 384-322) who 
 besides his own original contributions to science, 
 supplies valuable references to writings of his pre- 
 decessors which have not come down to us. His 
 treatises furnish an admirable exposition of the state 
 of natural knowledge in his time. When he wrote, 
 the geocentric view of the universe was still publicly 
 accepted without question. But he had firmly grasped 
 certain truths regarding our globe, which, though 
 taught long before by some of his predecessors, were 
 not yet generally admitted. Thus he recognized that 
 the planet possesses a spherical form, which is the 
 most perfect of all, and he pointed in proof to the 
 round shadow cast by the earth upon the moon during 
 a lunar eclipse. He showed also by the difference in 
 the aspect of the stellar heavens, as we move but a 
 little way from north to south or south to north, that 
 the mass of our globe must be relatively small. " The 
 size of the earth is nothing," he says, u absolutely 
 nothing, compared with the whole heavens. The 
 mass of the sun must be far greater than that of our 
 globe, and the distances of the fixed stars from us is 
 much greater than that of the sun." 1 Accepting the 
 common belief that the world consisted of four 
 elements, he looked on these as arranged according 
 to their relative densities. " The water is spread as 
 an envelope round the earth ; in the same way, above 
 1 MeteoricSy i. viii. 6 ; xiv. 1 8. 
 
Aristotle on Earthquakes 13 
 
 the water lies the sphere of air, while outside of all 
 comes the sphere of fire." 1 
 
 With regard to the surface of the planet, Aristotle 
 had formed some sagacious conclusions, though mingled 
 with certain of the misconceptions that were prevalent 
 in his time. In trying to gain a general impression of 
 the manner in which geological problems were treated 
 by him and the succeeding naturalists and philosophers 
 of antiquity we may find it convenient to consider 
 them under the three sections of (i) Underground 
 processes ; (2) Surface processes ; and (3) Evidence 
 of geological changes in the past. 
 
 i . Underground Processes. As Greece, from its special 
 geological structure, has from time immemorial been 
 subject to frequent earthquakes, the attention of the 
 more reflective men in the country must have been 
 early drawn to these subterranean disturbances and to 
 a consideration of their possible cause. Aristotle has 
 devoted a portion of his treatise on Meteorics to a 
 discussion of earthquakes, and has quoted the opinions 
 of some earlier philosophers in regard to them. He 
 tells us that Anaxagoras (B.C. 480) accounted for these 
 disturbances by the descent of the surrounding ether 
 into the depths of the earth ; that Democritus (B.C. 
 460-357) thought they were caused by the bursting 
 out of the mass of liquid within the earth, especially 
 after heavy rains ; and also, after the earth had become 
 desiccated by the great commotion arising from the fall 
 of water from the full spaces into those that were 
 empty ; and that Anaximenes (B.C. 544) supposed 
 
 1 Op. cit. ii. ii. 5. The sphere of fire, the "flammantia moenia 
 mundi" of Lucretius, was the region of the stars and planets. 
 
14 Aristotle on Earthquakes 
 
 them to be produced by the disruption of mountains 
 when the earth, at first full of water, dries up ; for 
 he remarked that they take place chiefly during 
 droughts and also during excessively wet seasons, 
 because in the one case the earth is dried and splits 
 up, while in the other, it gives way on account of 
 being saturated with liquid. 
 
 Rejecting the explanations of his three predecessors 
 just cited, Aristotle remarks that if some of their 
 views were true, earthquakes ought gradually to grow 
 less abundant and severe, until at last the earth should 
 cease to shake, but that as this diminution has not been 
 observed, another interpretation must be sought. He 
 accordingly proposes one of his own which is a curious 
 and memorable instance of imperfect observation and 
 inaccurate generalisation. Earthquakes are due, he 
 thinks, to a commingling of moist and dry within the 
 earth. Of itself, the earth is dry, but from rain it 
 acquires much internal humidity. Hence when it is 
 warmed by the sun and by the internal heat, wind is 
 produced both within and without its mass. Wind, 
 being the lightest and most rapidly moving body, is 
 the cause of motion in other bodies ; and fire, united 
 with wind, becomes flame which is endowed with great 
 rapidity of motion. It is neither water nor earth 
 which causes an earthquake ; it is the wind when 
 what is vaporised outside returns into the interior. 
 Remarking a relation between the frequency and 
 violence of earthquakes and the state of the weather, 
 Aristotle admits with Anaximenes that they occur most 
 abundantly in spring and autumn, during the seasons 
 of heavy rain and of great drought, but he thinks 
 
Aristotle on Volcanoes 15 
 
 that the reason of this relation should be sought in 
 the fact that during these seasons there is most wind. 1 
 
 Aristotle regarded earthquakes and volcanic erup- 
 tions as closely related phenomena. He states that it 
 had been observed in some places, that an earthquake 
 has continued until the wind from the interior has 
 rushed out with violence to the surface, as had 
 then recently happened at Heracleia on the Euxine, 
 and before that event at Hiera (Volcano), one of the 
 Lipari Isles. At this latter locality the ground rose 
 up with a great noise and formed a hill that broke 
 up and allowed much wind to escape from the fissures, 
 together with sparks and cinders which buried the 
 whole of the neighbouring town of the Liparans. 
 The shock was even felt in some of the towns on 
 the opposite mainland of Italy. 
 
 Aristotle was further led to propose an explanation 
 of the great heat that forms part of the volcanic 
 phenomena. c ' The fire within the earth," he remarks, 
 " can only be due to the air becoming inflamed by 
 the shock, when it is violently separated into the 
 minutest fragments. What takes place in the Lipari 
 Isles affords an additional proof that the winds circu- 
 late underneath the earth." 2 
 
 This idea that volcanic action was mainly due to 
 the movement of wind imprisoned within the earth 
 obtained wide credence in antiquity. Aeolus, the god 
 of the winds, was believed to have his abode under 
 the so-called Aeolian Isles, which are all of volcanic 
 origin, and among which eruptions have been taking 
 place since before the dawn of history. 
 
 1 Meteor. 11. vti., viii, 2 O/>. clt. n. viii. 20. 
 
1 6 Lucretius on Earthquakes 
 
 Aristotle in his wide survey of the organic and 
 inorganic kingdoms did not omit to consider the 
 nature of stones, metals and minerals, and to offer 
 his suggestions as to their possible origin. He sup- 
 posed the existence of two exhalations which play a 
 notable part in nature both inside and outside the earth. 
 One of these, the smoky or dry exhalation by burning 
 substances, gives rise to minerals and other kinds of 
 stone which are insoluble in water. The other or 
 vaporous exhalation produces the metals which are 
 fusible or ductile. Aristotle's favourite pupil, Theo- 
 phrastus (6.0.374-287) took up this subject in a 
 much more practical way in his tract on Stones, which 
 describes the external characters, sources and uses of 
 the more familiar rocks and minerals. Interesting as 
 a narrative of what was known and thought in his 
 day in regard to the mineral kingdom, it may be 
 claimed as the earliest essay in Petrography. His 
 treatise " On Fishes " contains a reference to remains 
 of fishes found in the rocks of Pontus and Paphla- 
 gonia. The philosopher thought that these fossils 
 were developed from fish-spawn left in the earth, or 
 that fishes had wandered from neighbouring waters 
 and had finally been turned into stone. He also 
 expressed the idea that a plastic force is inherent in 
 the earth whereby bones and other organic bodies are 
 imitated. 
 
 Lucretius, whose great poem, De Rerum Nafura, 
 appeared about half a century before the beginning 
 of our era, states with his characteristic force the 
 explanations then in vogue to account for the pheno- 
 mena of earthquakes. The interior of the earth, 
 
Lucretius on Volcanoes 17 
 
 he declares, must be full of wind-swept caverns, with 
 lakes, rivers, chasms and cliffs, as above ground. The 
 fall of some of these vast mountainous rocks, under- 
 mined by time, gives such a shock as to send gigantic 
 tremors far and wide through the earth. Again, 
 wind, collecting in these subterranean cavernous spaces, 
 presses with such enormous force against the walls 
 towards which it rushes as to make the earth lean 
 over to that side, and to topple down buildings 
 above ground. Sometimes the air, either from out- 
 side or from within, sweeps with terrific whirling vio- 
 lence into the vacant spaces underneath, until in its 
 fury it cleaves for itself a yawning chasm in the earth 
 by which it escapes to the daylight. Even when it 
 does not issue at the surface, its violence among the 
 many underground passages sends a tremor through 
 the earth. 
 
 The poet stating that he will explain how volcanic 
 eruptions, such as those of Etna, arise, declares that 
 the mountain is hollow within and that the wind and 
 air inside, when thoroughly heated and raging furiously, 
 heat the rocks around. Fire is thus struck out from 
 these rocks and with its swift flames is swept by the 
 air up the chasms, until it issues from the mountain- 
 top, hurling forth ashes, huge stones, and black smoke. 
 From the sea- floor caverns reach down into the depths 
 of the mountain, and the water that enters there, 
 mingled with air, rushes out again in blasts of flame 
 with showers of stones and clouds of sand. 1 We 
 are not definitely told, however, by what process the 
 heat inside is engendered, whether the explanation 
 1 Z)<? Rerum Natura, vi. 535-702. 
 
 B 
 
1 8 Sir abet s 'Geography' 
 
 of Aristotle was favoured, or the common belief in 
 subterranean accumulations of sulphur and other com- 
 bustible substances. 
 
 Coming down to the beginning of the Christian era, 
 we turn to the pages of Strabo, who besides availing 
 himself of the labours of his predecessors, more 
 particularly of those who wrote in Greek, travelled over 
 a considerable part of the ancient world, with observant 
 eyes as to what he himself saw and a critical judgment 
 as to what he heard from others. Though his great 
 work is mainly a description of the topographical and 
 political geography of his day, it is interspersed with 
 acute observations and reflections regarding the 
 physical features of the various countries, and the 
 natural processes whereby these features have been 
 produced or altered. His Geography^ therefore, con- 
 tains not a few important statements of fact in regard 
 to the general effects of subterranean energy. Thus 
 he cites a number of earthquakes by which chasms 
 in the ground were formed, thousands of people were 
 destroyed and cities were swallowed up. He also 
 gives some information regarding volcanic eruptions 
 which had taken place within the historical period 
 in the Mediterranean region. In his time Mount 
 Vesuvius was not only quiescent, but was not known 
 to have ever been active. His quick eye, however, 
 detected the true origin of the mountain. From 
 the aspect of its summit, he inferred that it was 
 once a volcano, with live craters which had become 
 extinct on the failure of the subterranean fuel, and 
 he compared its slopes to the ground around Catania, 
 where the ashes thrown out by Etna have formed 
 
Strabds Ideas of Volcanoes 19 
 
 an excellent soil for vines. He recognised the truly 
 volcanic nature of the whole district from Etna to 
 the Phlegraean Fields, under which Typhon, as Pindar 
 sang, lay crushed on his burning bed. 1 In his excellent 
 account of the ascent of Etna, Strabo compares the 
 molten lava to a kind of black mud which, liquefied in 
 the craters, is ejected from them and flows down the 
 sides of the mountain, cooling and congealing in its 
 descent, until it becomes a motionless dark rock like 
 millstone. 2 
 
 Strabo, however, made no advance on his predecessors 
 in regard to an explanation of the nature and cause 
 of volcanic action, which he continued to attribute to 
 the force of winds pent up within the earth. He 
 alludes to the connection between the state of the 
 weather and volcanic energy at the Lipari Isles, already 
 noticed by previous writers a connection which, so 
 far as it exists, doubtless tended to confirm the popular 
 attribution of the eruptions to the escape of subterranean 
 wind. The most important remark of this geographer 
 in regard to volcanic action is undoubtedly his obser- 
 vation that the district around the Strait of Messina 
 seldom suffers much from earthquakes, whereas 
 formerly, before the volcanic orifices of this region 
 were opened up, so as to allow of the escape of the 
 fire smouldering within the earth and of the im- 
 prisoned wind, water and burning masses, the ground 
 was convulsed with frightful earthquakes. The 
 doctrine that volcanoes are safety valves, which was 
 once thought to be a modern idea, is thus at least 
 as old as the beginning of the Christian era. 
 iRook vi. i. 5. 2 vi. ii. 3, 8. 
 
20 Strabo on Origin of Islands 
 
 Strabo cites examples of wide-spread and also local 
 sinkings of land, as well-known historical events, such 
 as the catastrophe that submerged the town of Helice 
 in Achaia, together with an extensive surrounding 
 district. He believed that to earthquakes and similar 
 causes were due the risings, slips and other changes 
 which at various times affect the surface of the earth, 
 and he held that deluges, earthquakes, eruptions of 
 wind, and elevations of the bottom raise the level of 
 the sea, which on the other hand, is lowered when 
 the bottom subsides. 1 
 
 The numerous islands in the Mediterranean Sea 
 occupied much of Strabo's attention. He appears 
 to have believed that their insular character arose from 
 two causes. Some he supposed to have been torn 
 from or joined to the mainland by such convulsions 
 as earthquakes, while others were obviously thrown 
 up by volcanic agency. Those which lie off headlands 
 he was inclined to attribute to the former cause ; 
 but those which stand in the middle of the sea seemed 
 to him to have been most probably thrown up from 
 the bottom. He does not appear, however, to have 
 had any settled grounds of belief upon this question, 
 for in one passage he speaks of Sicily having been 
 broken off from the mainland of Italy by earth- 
 quakes, 2 while elsewhere he thinks that this island 
 " may have been thrown up from the bottom of 
 the sea by the fires of Etna, as the Aeolian and 
 Pithecusan Isles (Ischia, etc.) have been." 3 He refers 
 to submarine eruptions among the Lipari Islands 
 that had given rise to islets or shoals of hard rock 
 1 Book i. iii. 10. 2 vi. i. 6. 3 i. iii. 10. 
 
Seneca s 'Natural Questions' 21 
 
 an interesting observation in connection with some 
 events in the recent history of this volcanic dis- 
 trict. 1 
 
 The philosopher Seneca, besides the treatises and 
 plays by which he is chiefly known, wrote towards the 
 end of his life a tract in which, under the title of 
 Natural Questions, he discoursed largely of the heavenly 
 bodies and of meteorological phenomena, and discussed 
 also, more fully than any previous writer whose work 
 has come down to us, some of the more important 
 geological processes of nature. He was born a few 
 years before the commencement of our era and met his 
 tragic fate in A. D. 65. As the tract in question refers 
 to events which had happened some time before, in the 
 spring of A.D. 63, it is probably his latest work. 
 Seneca appears to have been familiar with all the 
 literature of the subject up to his own time, and he 
 quotes and criticises the opinions of many of his 
 predecessors. Especially interesting are his disquisi- 
 tions on the flow of water at the surface and below 
 ground, and on the results and origin of earthquakes. 
 From his treatment of these matters he can be seen to 
 have been a shrewd observer and sagacious reasoner, 
 though still unable to advance much beyond the 
 opinions prevalent in his day, and still holding to some 
 of the most erroneous popular beliefs. Yet he clearly 
 recognized that the system of Nature is no capricious 
 series of events, liable at any moment to be interrupted 
 and changed by the fiat of some irascible divinity. 
 " Though the processes below ground," he remarks, 
 " are more hidden from us than those on the surface 
 
22 Seneca on Earthquakes 
 
 of the earth, they are none the less equally governed 
 by invariable laws." 
 
 Seneca appears to have been much impressed by the 
 earthquake which did so much damage in Campania on 
 5th February A.D. 63, for he refers to it again and 
 again, and furnishes from the lips of eye-witnesses some 
 interesting particulars regarding it. Thus he tells how 
 a flock of 600 sheep were killed in the district of 
 Pompeii, a fate which he attributes to the rise of 
 pestilential vapours from the ground. He was in- 
 formed by a most learned and serious friend that when 
 he was in the bath the tiles on the floor were separated 
 from each other and were then driven together again, 
 while the water at one moment sank through the 
 opened joints of the pavement, and thereafter boiled up 
 again and was jerked out. The philosopher's account 
 is the earliest detailed description of an earthquake, 
 which has come down to us. The recentness of the 
 event, the serious nature of the damage done, and the 
 abundant narratives of those who had been in the midst 
 of the calamity led him to consider the effects and 
 causes of earthquakes more at large than had been done 
 before his time. 
 
 After giving a graphic picture of the terror of the 
 human mind when the ground beneath our feet is 
 convulsed, and the one thing in the world that seemed 
 securely fixed gives way beneath us, he ridicules the 
 action of those who from fright deserted Campania and 
 vowed they would never return. Where, he asks, can 
 they promise themselves to find a more steadfast soil? 1 
 
 1 Little did he realise the volcanic nature of the ground and the 
 potential possibilities of destruction which were to be manifested 
 
Seneca on Earthquakes 23 
 
 We run the same risks everywhere, for no part of the 
 wide earth is immovable. He then proceeds to 
 enumerate the various explanations that up to his day 
 had been proposed to account for the phenomena. 
 Among these he cites that of Anaximenes as to the 
 collapse of subterranean portions of the earth. But he 
 himself adheres to the view which had now been 
 adopted by the majority of authors, including those 
 of most weight, who supposed the cause to lie in 
 the movements of wind imprisoned beneath the earth. 
 He offers a long disquisition on the manner in which 
 he conceives that the subterranean wind acts. Nothing 
 known to us, he states, is more powerful or more 
 penetrating than air in motion. Without its aid none 
 of the other forces in nature, even those which are 
 most energetic, are of any avail. As beneath the 
 earth there are abundant hollows, with rivers, lakes 
 and large bodies of water, which have no exit above 
 ground, so in these dark caverns and recesses the 
 heavy air is pressed down and by its motion gives 
 rise to currents of wind. The force of these currents 
 is increased in proportion to the impediments in the 
 way of their escape, until they find a vent to the 
 surface. 
 
 Seneca distinguishes between the up-and-down move- 
 ment (sttccussio) in earthquakes and the oscillatory 
 movement (indinatio) like that of a ship at sea. He 
 thinks that even a third kind of motion should be 
 recognised, that of trembling or vibration. He 
 
 only sixteen years after the Campanian earthquake by the outbreak 
 of Vesuvius in A.D. 79, and the overwhelming of Pompeii and 
 Herculaneum. 
 
24 Seneca on Volcanoes 
 
 believes that each of these motions arises from a 
 different cause. Thus the trembling or vibratory 
 phase, like that produced by the passage of a heavily- 
 laden wagon, or like that arising from a landslip, may 
 be due to the collapse of the sides of subterranean 
 cavities, when the rocks fall with great weight and 
 noise into the recesses below. These catastrophes may 
 sometimes be aided by the abrading power of the 
 overlying rivers, and the constant action of water in 
 widening and weakening the fissures of rocks. When 
 the concussion is so great as to shake down the walls 
 by which the roof of one of these underground empty 
 spaces is supported, the whole ground will give way and 
 sink into the abyss, carrying down large tracts of the 
 surface and even entire cities. 
 
 This philosopher recognized the local character of 
 earthquakes, and connected the limitation of their 
 extent with the restricted dimensions of the subter- 
 ranean caverns where the wind is developed. If it 
 were not so, he remarks, wide tracts of country would 
 be agitated and many places would totter at the same 
 time. But the movement never extends beyond a 
 distance of two hundred Roman miles, and he points 
 once again to the recent example that had filled the 
 Roman world with its renown, yet did not itself travel 
 outward beyond the bounds of Campania. 
 
 Volcanoes form the subject of some interesting 
 remarks in Seneca's treatise. He refers to various 
 eruptions in the Italian and Greek centres of volcanic 
 activity. In speaking of two outbreaks at Santorin 
 he remarks that an island rose out of the sea by 
 protracted eruptions from below, and he notes that 
 
Seneca on Volcanoes 25 
 
 the internal fire is neither extinguished by the 
 weight of the superincumbent depth of sea, nor pre- 
 vented from rushing to a height of a couple of 
 hundred paces above the water. 1 He speaks of Etna 
 having sometimes abounded in much fire, and thrown 
 out a great deal of burning sand, day being turned 
 into night, to the terror of the population. On such 
 occasions, thunder and lightning are said to have 
 abounded ; but these came from the concourse of 
 dry materials, and not from ordinary clouds, of which 
 probably there were none in such a raging heat of 
 air a shrewd anticipation of the modern distinction 
 between ordinary atmospheric electric discharges and 
 those evoked during the ejection of vapours, gases, 
 dust, and stones from a volcanic orifice. 2 
 
 Following the general opinion of the learned men 
 who had preceded him, Seneca had no doubt that 
 volcanic eruptions, like earthquakes, were due to the 
 struggles of subterranean wind to break out to the 
 surface. It is evident, he says, that underground 
 there is a great store of sulphur, and of other sub- 
 stances not less capable of combustion. When the 
 subterranean wind in seeking an outlet has whirled 
 itself through these places, it must in so doing set 
 these inflammable things on fire by mere friction. 
 The flames spreading, in spite of the somewhat 
 sluggish air, make way with vast noise and force, 
 and find at last their escape to the surface, as at 
 Etna and elsewhere. There are fires covered up 
 within the earth, some of which occasionally burst 
 forth ; but a vast number are always burning in 
 1 Book ii. xxvi. 5. 2 n. xxx. i. 
 
26 Pliny s 'Natural History' 
 
 concealment. 1 As the result of these subterranean 
 commotions, new mountains are raised and new 
 islands are placed in the midst of the sea. " Who 
 can doubt, for instance," the philosopher asks, " that 
 wind gave birth to Thera and Therasia, and to the 
 younger island which even in our own time we have 
 seen spring up in the Aegean sea ? " 
 
 Another work of Seneca's time deserves mention 
 here the voluminous Natural History of the Elder 
 Pliny, in which so vast a mass of miscellaneous notes 
 has been compiled regarding the plants, animals, and 
 minerals known to the ancients, and the earthquakes, 
 volcanic eruptions, inundations and other natural 
 events which had happened within the times of 
 history. 2 Though rather a chronicler of other men's 
 opinions and experiences than himself an original 
 observer, he must have been imbued with a keen 
 interest in every department of Nature, as he cer- 
 tainly was endowed with portentous and unwearied 
 industry in gathering together all the information 
 that could be ascertained from every source. The 
 graphic picture which we have of him in his nephew's 
 letters to Tacitus shows him as the eager and 
 enthusiastic naturalist, keenly interested in every 
 phenomenon, ready with his tablets to make a note 
 of all that he saw or heard or read, and strictly 
 methodical and austerely temperate in his habits of 
 
 1 Book v. xiv. ; 11. x. 4. 
 
 2 Those who are interested in such matters will find a useful 
 compendium of Pliny's remarks on minerals, rocks, earthquakes 
 and volcanoes in Dr. H. O. Lenz's Mineralogie der Alten Gricchen 
 und Romer, Gotha, 1861. 
 
Pliny on Earthquakes 27 
 
 life. It must always be remembered that it was in 
 the pursuit of scientific knowledge that he lost his 
 life by venturing too near the scene of the disastrous 
 eruption of A.D. 79, which overwhelmed Herculaneum 
 and Pompeii. If the tradition be correct that Empe- 
 docles met his death by approaching too close to the 
 edge of the crater of Etna, this philosopher may 
 perhaps be claimed as a victim to the desire to 
 explore the mysteries of volcanic action. But in the 
 case of Pliny there is no uncertainty. He is enrolled 
 for all time as the first definitely recorded martyr to 
 the cause of geological science. 
 
 After referring to the opinion of the Babylonians 
 that earthquakes and all allied phenomena are to be 
 ascribed to the influence of the stars, Pliny remarks : 
 " My own belief is that they are caused by wind. 
 They only occur at times of complete calm, when 
 the wind, having sunk down into the subterranean 
 chasms, breaks forth once more." J He enumerates 
 a number of earthquakes of note, and in discussing 
 the phenomena that take place in connection with 
 them on land and sea, he states that towns with 
 numerous culverts and houses with cellars suffer less 
 than others, and that, for example in Naples, those 
 houses are most shaken which are built on hard 
 ground. He likewise recounts instances of volcanic 
 eruptions and the appearance of new volcanic islands, 
 but without throwing any light on the causes of 
 these disturbances. 
 
 It thus appears that during classical antiquity no 
 perceptible advance had been made in the investigation 
 1 Hut. Nat. ii. 8 1. 
 
28 Herodotus and Aristotle on Rivers 
 
 of the nature and cause of earthquakes and volcanoes. 
 The idea that both of these manifestations of hypogene 
 energy arise from the action of air imprisoned within 
 the earth and struggling to escape continued to hold 
 its ground, the heat and fire of volcanoes being re- 
 garded as probably due to the action of the internal 
 wind in setting fire to sulphur, bitumen or other 
 combustible substances. 
 
 2. Processes at work on the surface of the earth. 
 Among the geological agents which alter the face of 
 the land, rivers have naturally occupied much of the 
 attention of mankind in all ages. Herodotus during 
 his visit to Egypt was greatly interested in the Nile, 
 and he devotes some space to a discussion of the 
 remarkable characteristics of this stream. He enum- 
 erates and criticises the various explanations which had 
 been given of its annual rise, but without venturing 
 on any definite conclusion himself. He recognises 
 however the significance of the yearly deposit of silt 
 on the surface of the country, and concludes that 
 u Egypt is the gift of the river." 
 
 Aristotle discusses the phenomena presented by rivers, 
 and shows considerable acquaintance with the drainage 
 system on the north side of the Mediterranean basin. 
 He criticises previously expressed opinions as to the 
 source of rivers, particularly ridiculing the sugges- 
 tion of Plato that all rivers flow directly from a vast 
 mass of water under the earth. He appears to have 
 held the opinion that just as the vaporised moisture 
 in the atmosphere is condensed by cold and falls in 
 drops of rain, so the moisture beneath the earth is 
 similarly condensed and forms the sources of rivers. 
 
Strabo on Rivers 29 
 
 He states that the mountains, by their cold tempera- 
 ture, condense the atmospheric moisture and receive 
 a vast quantity of water, so that they may be com- 
 pared to an enormous suspended sponge. He shows 
 by geographical illustrations, drawn from Asia and the 
 Mediterranean basin, that the largest rivers descend 
 from the loftiest ground, where the water accumu- 
 lates in numberless channels. He admits the possible 
 existence of underground lakes from which rivers may 
 issue, and alludes to the disappearance of some streams 
 into subterranean channels. 
 
 Aristotle, moreover, reflected profoundly on the 
 geological operations of rivers. Recognising the 
 truth of the observation that the plain of Egypt had 
 been built up by the deposits of the Nile, he also 
 noted that along the shores of some parts of the 
 Black Sea the river alluvia had increased so much 
 in sixty years that the vessels in use there had to 
 be much smaller than formerly, and that in this case, 
 as in so many others, the silting up might go on 
 until the marsh-land became dry ground. Similar 
 changes were then in progress on the Bosphorus. 
 The contemplation of these and other vicissitudes led 
 the philosopher to some striking generalisations as to 
 the past and the future of the surface of our globe, 
 to which reference will be made on a later page. 
 
 To Strabo we are indebted for some sagacious 
 observations on the hydrography of the Mediterranean 
 basin. He points out that, like the Nile, the other 
 rivers that enter this sea form extensive alluvial 
 deposits at their mouths, as well as inland over the 
 low grounds, and he specially instances the plains of 
 
30 Seneca on Water-Cimilation 
 
 the Hermes, Cayster, Maeander and Caicus as having 
 been formed by the streams that flow through them. 1 
 The deltas vary, he thinks, according to the nature 
 of the regions drained, being most developed where 
 the country is large and the surface rocks are soft, 
 and where the rivers are fed by many torrents. He 
 remarks that these accumulations are prevented from 
 advancing further outward into the sea by the ebb 
 and flow of the tides. 2 
 
 Strabo believed the outflowing currents of the 
 Mediterranean Sea, as well as that of the Bosphorus, 
 to be due to the escape of the surplus water that 
 drains into the basin. In the course of his narrative 
 he is led to discuss the question of the opening of 
 a connection between the Black Sea and the Medi- 
 terranean, and between this latter and the outer 
 ocean. He expresses the opinion that we should not 
 be surprised if the Isthmus of Suez were to be dis- 
 rupted or to subside, so as to allow the Mediterranean 
 and Red Sea to be joined together. 3 
 
 In his philosophical survey of Nature and its pro- 
 blems, Seneca found room for a consideration of the 
 water-circulation of the globe. His reflections on this 
 subject show that in one important respect he had 
 not advanced beyond the position of Aristotle. In 
 his essay already cited he discusses at some length 
 the various kinds of terrestrial waters, noting their 
 tastes, temperature, uses, effects and other features. 
 He speaks of himself as a diligent wine-grower,* and 
 
 1 Book xv. i. 1 6. 2 i. iii. 7, 8. 3 i. iii. 6, 7, 17. 
 
 4 Seneca evidently used his eyes to some purpose in the country. 
 He calls attention to the remarkable power of vegetation in displacing 
 
Seneca on Underground JVater 31 
 
 in this capacity he had noted that the heaviest rain 
 does not moisten the earth for more than ten feet 
 downward, most of it flowing off into the beds of 
 streams. He gives his opinion, therefore, that rain 
 may make a torrent or help to swell a stream, but 
 that it cannot of itself be the source of a river flowing 
 with an equable course between its banks. If he is 
 asked whence, then, does the water of rivers come, 
 he replies that the question is as inept as it would 
 be to demand where air and earth come from. Water 
 being one of the four elements forms a fourth part 
 of nature. Why then should we be surprised if it can 
 always keep pouring out ? He knows that just as 
 in the human body there are veins which when 
 ruptured send forth blood, so in the earth there are 
 veins of water which are found even in the driest places, 
 at depths of two or three hundred feet below the 
 surface, and which when laid open issue in springs 
 and rivers. The water at these depths, so far below 
 the limits to which rain can moisten the earth, is not 
 regarded by him as of atmospheric origin, but living 
 water (aqua viva), for as all things are contained in 
 all, the earth, water and air can pass into each other. 
 The earth contains water which it presses out and 
 also air which, by the cold of winter, it condenses 
 into moisture ; the earth itself is also resolvable into 
 moisture. 
 
 Coming to the consideration of water at the surface, 
 he is on sounder ground when he discusses the 
 regime of rivers. He can see no more reason why 
 
 stones and destroying monuments, even the most minute and slender 
 rootlets being able to split open large rocks and crags, n. vi. 5. 
 
32 Seneca on Rivers 
 
 we should wonder at the changes of volume in rivers 
 than we do at the regular succession of the seasons. 
 After an excellent account of a flood on the Danube, 
 of which we may believe him to have been an eye- 
 witness, he enters upon a discussion of the rise of 
 the Nile which he describes as it appears at Philae. 
 In rejecting the popular opinion expressed by the 
 tragedians that the cause of this annual phenomenon 
 is to be sought in the melting of snow on the 
 mountains of Ethiopia, he repeats the arguments of 
 Herodotus (whom however he does not cite) but with 
 the interesting addition, which he may have derived 
 from the explorers sent by Nero to the south of 
 Egypt, that in Ethiopia no hibernating animal had 
 ever been found, and that the serpent may be seen 
 there in winter even on the open high grounds. 1 
 
 The effects of floods in destroying woods, houses 
 and flocks are described, and the philosopher, in his 
 characteristic way, turns from a contemplation of these 
 events to moralise over the destiny of mankind. He 
 asks in what manner, when the fatal day of the 
 deluge shall arrive, will a large part of the earth's 
 surface be destroyed by water, whether the great ocean 
 will overwhelm us, or ceaseless torrents of rain, or 
 prolonged winter, pouring deluges from the clouds, 
 or rivers swollen into floods, and torrents rushing from 
 newly opened sources, or whether it will be by no 
 single agency, but when all will conjoin together ; when 
 rains will descend, rivers will overflow, the sea will 
 issue from its depths and all will sweep in one fell 
 array against the human race. 2 
 
 1 Book iv. ii. 7-30. 2 in. xxvii. 
 
Geological Observations by the Greeks 33 
 
 3. Proofs of geological changes in the past. Through- 
 out the Mediterranean basin the profusion of well- 
 preserved marine shells in the upraised younger 
 formations which underlie the lowlands and crop out 
 along the sides of the hills, must have attracted the 
 notice of the earliest inhabitants. Accordingly we find 
 in Greek literature frequent allusion to them and to 
 the inference deduced from them that many tracts 
 of land had once lain beneath the sea. Xenophanes 
 of Colophon (B.C. 614) is recorded to have written 
 concerning sea-shells found among the inland hills 
 in Malta and elsewhere, and to have concluded from 
 them that they prove periodical submergences of the 
 dry land, wherein man and his dwelling-places have 
 been involved. Xanthus the Lydian (B.C. 464) is 
 quoted by Strabo as having seen shells like cockles and 
 scallops, far from the sea, in Armenia and Lower 
 Phrygia, and having inferred, from this evidence and 
 that of scattered salt-lakes, that these regions had 
 once been submerged beneath the sea. 1 Herodotus 
 noticed petrified sea-shells in the hills of Egypt, 
 especially those near the oasis of Jupiter Ammon, 
 and he too concluded from them, and from the saline 
 crust on the ground, that the sea had once spread over 
 Lower Egypt. 2 Some centuries later these observa- 
 tions were confirmed by Eratosthenes (B.C. 276-196) 
 who noted vast quantities of marine shells 2000 or 
 3000 stadia from the sea and for a distance of 3000 
 stadia along the road to the Ammon oasis, together 
 with beds of salt and saline springs. 3 Strato (B.C. 288) 
 also is quoted by Strabo as having come to the 
 
 1 Strabo, i. iii. 4. 2 n. 12. 3 Quoted by Strabo, loc. cit. 
 
 C 
 
34 Aristotle on Geological Revohitions 
 
 conclusion that the temple of Jupiter Ammon was 
 once near the sea, which then spread over Egypt as 
 far as the marshes, near Pelusium, Mount Casius and 
 the Lake Sirbonis. He speaks of salt being dug in his 
 time in Egypt under layers of sand mingled with shells, 
 as if the whole region had formerly been covered by 
 a shallow sea that stretched across to the Arabian 
 Gulf. 1 
 
 No writer of antiquity has expressed himself more 
 philosophically than Aristotle regarding the past vicissi- 
 tudes of the earth's surface. Having studied so 
 carefully the operations of the various agents that are 
 now modifying that surface, he recognised how greatly 
 the aspect of the land must have been transformed 
 in the course of ages. His remarks on this subject 
 have a strikingly modern tone. He contemplates the 
 alternations of land and sea and furnishes- illustrations 
 of them, much as a geologist of to-day may do. 
 " The sea," he says, " now covers tracts that were 
 formerly dry land, and land will one day reappear 
 where we now find sea. We must look on these 
 mutations as following each other in a certain order, 
 and with a certain periodicity, seeing that the interior 
 of the globe, like the bodies of animals and plants, 
 has its periods of vigour and decline, with this dif- 
 
 1 Loc. fit. Strabo narrates his own experience as to fossils in the 
 rocks of Egypt. When standing in front of the Pyramids he noticed 
 that the blocks of stone that had been brought from the quarries 
 contained pieces which in shape and size resembled lentils (nummu- 
 lites) and he was told that these were remnants of the food of the 
 workmen turned into stone an explanation which he rejects as 
 improbable, though he cannot suggest a likely origin for them. xvn. 
 i- 34- 
 
Aristotle on Geological Revohttions 35 
 
 ference, however, that while the whole of an organ- 
 ism flourishes and then dies, the earth is affected only 
 locally. 
 
 " These phenomena escape our notice because they 
 take place successively during periods of time, which, 
 in comparison of our brief existence, are immensely 
 protracted. Whole nations may disappear without 
 any recollection being preserved of the great terrestrial 
 changes which they have witnessed from beginning 
 to end. So too the increase in the area of habitable 
 land is brought about so imperceptibly in the course 
 of long ages that we can neither tell who were the 
 first inhabitants to settle in such new tracts, nor in 
 what condition they found the land." After quoting 
 in illustration the early history of Egypt and of the 
 territories of the Argives and Mycenians in Greece, 
 he remarks that what had transpired in a little district 
 appears to take place in precisely the same way in 
 more extensive regions and over entire countries. He 
 then proceeds to consider how these vicissitudes of 
 topography are to be accounted for. 
 
 " The cause to which such terrestrial mutations are 
 to be assigned may perhaps be that just as winter 
 regularly recurs among the seasons of the year, so a 
 great winter, lasting through a vast period of time, may 
 arise, bringing with it an excessive rainfall. Such a pre- 
 cipitation would not always affect the same countries. 
 Decalion's deluge, for example, only extended over 
 old Hellas which lies near to Dodona and the river 
 Achelous, which has often shifted its course. Land 
 that is lofty and has a cold temperature gives rise to 
 and retains an abundance of water which keeps it 
 
36 Strabo's Geological Speculations 
 
 perpetually moist, while lower grounds, especially 
 where the rocks are porous, are the first to be dried 
 up. In course of time one area becomes more or 
 less desiccated, until a fresh return of a great period 
 of inundation." * 
 
 As geographical proof of the probability of these 
 suggestions, he refers again to the early condition of 
 Egypt. Herodotus had long before announced his 
 belief that the Nile had filled up with its sediments 
 the tract between Thebes and Memphis, once an 
 inlet of the sea, and had continued to push out its 
 silt so as to form the delta. Aristotle, enlarging on 
 the statements of the historian, declares that Egypt 
 was evidently at one time covered by a continuous 
 sea, and that the Nile, with its annual burden of 
 sediment, has shallowed this expanse of water, turning 
 it first into marshes which by degrees became entirely 
 dried up. He concludes with these remarkable words : 
 " It is clear that, as time never stops and the universe 
 is eternal, the Tanais and the Nile, like all other 
 rivers, have not always flowed ; the ground which 
 they now water was once dry. But if rivers are born 
 and perish, and if the same parts of the land are 
 not always covered with water, the sea must undergo 
 similar changes, abandoning some places and returning 
 to others, so that the same regions do not remain 
 always sea or always land, but all change their con- 
 dition in the course of time." 2 
 
 Though Strabo was more intent on recording geo- 
 graphical facts than indulging in geological speculations, 
 he could not refrain from sometimes intercalating a 
 1 Meteor, i. xiv. i et seq. 20. 2 Op. clt. i. xiv. 3 1 . 
 
Ovid's Pythagorean Philosophy 37 
 
 pregnant remark as to the connection of the present 
 with the past. In regard to the interchange of land 
 and sea in former periods he held firmly to the doc- 
 trine so clearly expounded by the earlier philosophers. 
 " Every one will admit," he writes, " that at various 
 periods a great portion of the mainland has been 
 covered and again left bare by the sea." "All things 
 are continually in motion and undergo great changes, 
 much of the land being turned into water, and much 
 of the water changed into land. Some parts of the 
 earth now inhabited by man once lay beneath the sea, 
 while some portions of the bed of the sea were once 
 inhabited land." 1 
 
 The poet Ovid (B.C. 43-A.D. 18), who flourished 
 about the same time as Strabo, in a well-known passage 
 in the I5th book of his Metamorphoses represents 
 Pythagoras as himself expounding his view of the 
 system of Nature. This philosopher's doctrines have 
 only come down to us reported and perhaps distorted 
 by others. As Ovid introduces into Pythagoras' dis- 
 course allusions to some incidents which took place 
 long after the philosopher's death, the narrative cannot 
 be regarded as historically accurate, or as more than a 
 digest of what, in the time of Augustus, was believed 
 to be the Pythagorean philosophy. The sage is repre- 
 sented as maintaining that the world is eternal and 
 consists of the four elements air and fire above, 
 water and earth below. " Nothing in this world 
 perishes but only varies its form ; to be born is 
 merely to begin to be something different from what 
 we were before, and to die is to cease to be that same 
 
 1 Book xvn. i. 36. 
 
38 Ovid on Geological Revolutions 
 
 thing. In spite of all transformation, the sum of 
 everything remains constant." The vicissitudes of 
 the earth's surface are then enumerated, and historical 
 examples of some of them are given. They may be 
 summarised in the subjoined paragraphs. 
 
 What was once solid land is now covered by the 
 sea, and new lands have been made out of the deep. 
 Sea shells have been found far inland, and the anchor 
 on a mountain crest. 
 
 Former plains have been carved into valleys by the 
 descending waters, and thus mountains have been 
 washed down into the sea. 
 
 Ancient lakes have been turned into tracts of burn- 
 ing sand, and dry ground has been changed to stagnant 
 marshes. 
 
 Nature has opened new springs in some places, and 
 elsewhere has closed up the old ones. 
 
 By former earthquakes many rivers have been made 
 to spring forth, or to sink down and disappear. 
 
 Places that were once islands, like Antissa, 
 Pharos and Tyre are now joined to the mainland, 
 and, on the other hand, tracts of once continuous 
 land are separated by sea-straits like the island of 
 Leucadia. 
 
 Cities have been submerged beneath the sea, as in 
 the case of Helice and Buris of which the walls, still 
 standing inclined beneath the waves, are pointed out 
 by the sailors. 
 
 Plains may be turned into hills, as happened at 
 Troezene where the violence of the winds, im- 
 prisoned in their dark caverns within the earth and 
 unable to find egress, heaved up the ground like 
 
Ovid on Volcanoes 39 
 
 a bladder and made a prominent hill which still 
 endures. 1 
 
 Waters vary in temperature, some being cold during 
 the day and warm at morning and evening. Others 
 (accompanied with petroleum or inflammable gas) can 
 set wood on fire. Some have a petrifying quality, and 
 others have varying effects on the human body and 
 mind. 
 
 Islands once floating have become fixed, like the 
 ancient Ortygia which is now Delos, and the Sym- 
 plegades, which once terrified the Argo, but are now 
 anchored, and firmly defy the tempests. 
 
 Etna which now glows with its sulphurous furnaces 
 will not always be a burning mountain, and there was 
 a time before it began to burn. Whether the earth 
 is an animal that lives and breathes [forth flames from 
 many vents ; or winds pent up within the earth break 
 out and cast up stones and flame until the caverns 
 are emptied and cooled ; or some bituminous mass 
 has taken fire and burns until it dies away in faint 
 fumes of yellow brimstone ; a day will come when 
 the fires within will die out for lack of fuel. 
 
 From this sketch of the knowledge possessed by 
 the ancients regarding geological processes it appears 
 that while some sound observations had been made 
 and a certain amount of correct information had been 
 gathered together, speculation as to the causes of 
 things was much more cultivated than the patient 
 collection and comparison of facts. The same fanciful 
 
 J An account of this eruption is given by Strabo (i, iii. 18) and 
 its effects have been described by the late Professor Fouque of Paris, 
 Compt. rend. Ixii. pp. 904, 1121, and by other later writers 
 
, 
 
 40 Character of Geology of the Ancients 
 
 hypothesis was accepted and reiterated for centuries, 
 without apparently any effort being made to test or 
 verify it by actual observation of nature. Certain 
 vague and more or less obvious inferences were drawn 
 as to ancient changes in land and sea, and some of 
 these changes were correctly referred to the agencies 
 that produced them. Yet the epigene forces of nature 
 were but partially comprehended, while the hypogene 
 activities were entirely misunderstood. Not even the 
 faintest suspicion had yet dawned on the minds of 
 men as to the long succession of events in the great 
 terrestrial evolution which geology has revealed. In 
 short nothing in this department of knowledge had 
 yet been accumulated to which the name of science 
 could be applied. 
 
 In one important respect, however, a momentous 
 forward step had been taken in the intellectual pro- 
 gress of mankind. The primeval belief that Nature 
 was governed by impulsive and capricious divinities, 
 interfering continually with the sequence of events, 
 had for centuries disappeared from the creed of all 
 reflective men, though it still found rhetorical ex- 
 pression among the poets. In its place had come 
 a more or less definite recognition that the world is 
 regulated by laws which, invariable and impartial in 
 their operation now, had been at work from the 
 beginning. The spread of this more enlightened con- 
 ception was happily untrammelled by any active 
 opposition either from a jealous priesthood or from 
 popular animosity. Each philosopher was at liberty 
 to hold and to express the views which he chose to 
 adopt, and while the old religion of classic paganism 
 
Freedom of the Ancients 41 
 
 slowly lost its hold on the people, the rise of Chris- 
 tianity at first offered no impediment to the freedom 
 of philosophical inquiry. The fate of the Roman 
 Empire and the inroads of the barbarians arrested for 
 centuries the progress of natural history investigation. 
 When this progress was resumed towards the end of 
 the Middle Ages, a new spirit of intolerance had 
 arisen from which Antiquity had been free. 
 
 
CHAPTER II 
 
 GROWTH of geological ideas in the Middle Ages Avicenna and the 
 Arabs : Baneful influence of theological dogma. Controversy 
 regarding the nature of fossil organic remains. Early observers 
 in Italy Leonardo da Vinci, Falloppio, Steno, Moro. The 
 English cosmogonists Burnet, Whiston, Woodward. Robert 
 Hooke, John Ray, Martin Lister, Robert Plot, Edward 
 Lhuyd. 
 
 DURING the centuries that succeeded the fall of the 
 Western Empire such learning as survived in Europe 
 was to be found only in the monasteries and other 
 ecclesiastical establishments. But it concerned itself 
 little with natural knowledge, save in as far as this was 
 contained in the works of the writers of antiquity. 
 From about the middle of the eighth century onwards 
 for some five hundred years, the Arabs kept alive 
 the feeble flame of interest in researches into the secrets 
 of Nature. With great labour and at large cost, they 
 procured as much as they could obtain of the literature 
 of Ancient Greece and Rome, and studied and translated 
 [into their own language the works of the best 
 writers in philosophy, medicine, mathematics and 
 astronomy. They were thus able to some extent to 
 enlarge the domain of these subjects. One of the most 
 
Contents xi 
 
 CHAPTER XIII 
 
 Progress of Stratigraphical Geology The Transition or Greywacke 
 formation resolved by Sedgwick and Murchison into the Cam- 
 brian, Silurian and Devonian systems. The Primordial Fauna 
 of Barrande. The pre-Cambrian rocks first begun to be set in 
 order by Logan, - - pp. 406-437 
 
 CHAPTER XIV 
 
 Progress of Stratigraphical Geology continued Influence of Charles 
 Darwin. Adoption of Zonal Stratigraphy of fossiliferous rocks. 
 Rise of Glacial Geology, Louis Agassiz. Development of Geo- 
 logical map-making in Europe and North America, pp. 438-461 
 
 CHAPTER XV 
 
 The Rise of Petrographical Geology William Nicol, Henry Clifton 
 Sorby. Conclusion, - pp. 462-473 
 
 INDEX,- - - - p. 474 
 
Amcennas Views in Geology 43 
 
 illustrious of the Arab authors was the famous Avicenna 
 (Ibn-Sina, 980-1037), the translator of Aristotle, whose 
 views he largely adopted. But if the volume " On 
 the conglutination of Stones " be truly ascribed to him, 
 he expressed, more clearly than his Greek master, 
 opinions regarding the origin of mountains and valleys 
 which show a singular forecast of modern geology. 
 " Mountains," he says, " may arise from two causes, 
 either from uplifting of the ground, such as takes 
 place in earthquakes, or from the effects of running 
 water and wind in hollowing out valleys in soft rocks 
 and leaving the hard rocks prominent, which has been 
 the effective process in the case of most hills. Such 
 changes must have taken long periods of time, and 
 possibly the mountains are now diminishing in size. 
 What proves that water has been the main agent in 
 bringing about these transformations of the surface, is 
 the occurrence in many rocks of impressions of aquatic 
 and other animals. The yellow earth that clothes the 
 surface of the mountains is not of the same origin as 
 the framework of the ground underneath it, but arises 
 from the decay of the organic remains, mingled with 
 earthy materials transported by water. Perhaps these 
 materials were originally in the sea which once over- 
 spread all the land." 
 
 With the revival of learning in Europe, attention 
 was once more drawn to the problems presented by the 
 rocks that form the dry land. More particularly did 
 the occurrence of fossil shells, far distant from the 
 sea, arouse inquiry. We have seen that in the days of 
 ancient Greece and Rome the questions suggested by 
 these objects did not wholly escape attention, and that 
 
44 Theories of the Middle Ages 
 
 while, in general, no doubt was cast upon their organic 
 origin, the natural conclusion was drawn from them 
 that they proved the sea to have once overspread the 
 land. 
 
 This deduction was likewise adopted after the revival 
 of learning. But by this time the Church had gained 
 such an ascendency over the minds of men that no 
 opinions were allowed to be promulgated which 
 appeared to run counter to orthodox beliefs. If 
 therefore an observer who found abundant sea-shells 
 imbedded in the rocks forming the heart of a mountain 
 chain ventured to promulgate his conclusion that these 
 fossils prove the mountains to consist of materials 
 that were accumulated under the sea, after living 
 creatures appeared upon the earth, he ran imminent 
 risk of prosecution for heresy, inasmuch as according 
 to Holy Writ, land and sea were separated on the 
 third day of creation, but animal life did not begin 
 until the fifth day. Again, the overwhelming force 
 of the evidence from organic remains that the 
 fossiliferous rocks must have taken a long period 
 of time for their accumulation could not fail to 
 impress the minds of those who studied the sub- 
 ject. But to teach that the world must be many 
 thousands of years old was plainly to contradict the 
 received interpretation of Scripture that not more 
 than some 6000 years had elapsed since the time of 
 the Creation. 
 
 To court martyrdom on behalf of such speculative 
 opinions was not a course likely to be followed by 
 many enthusiasts. Various shifts were accordingly 
 adopted, doubtless in most cases honestly enough, in 
 
The Controversy about Fossils 45 
 
 order to harmonise the facts of Nature with what 
 was supposed to be the divine truth revealed in the 
 Bible. A favourite mode of escape from the difficulty 
 consisted in denying that the fossils ever formed part 
 of living creatures. The old notion, first suggested by 
 Theophrastus, was revived, to the effect that there 
 exists within the earth a plastic force by which imitative 
 forms are produced, resembling those of true organisms, 
 but in reality as inorganic in origin as the plant-like 
 forms made by frost on window-panes. The fossils 
 were regarded as simply mineral concretions, and were 
 described as lusus naturae, mere freaks of Nature, 
 lapides sui generis, lapides figurati, " figured " or 
 " formed" stones. 1 Some writers, unable to detect 
 the action of any such formative agency in the earth 
 itself, supposed that the occult influence came from 
 the stars. 
 
 There were many observers, however, who could 
 not gainsay the evidence of their own senses, and 
 who recognised that either we must believe that 
 the minute and perfectly-preserved organic structures 
 in the fossils could only have belonged to once 
 living plants and animals, like those which possess 
 similar structures at the present day, or that the 
 Creator had filled the rocks of the earth's crust with 
 
 1 The earliest account of these objects accompanied with illustrative 
 plates was that of the distinguished Conrad Gesner (1516-1565) 
 De rerum fossi/tum, lapldum et gemmarum fguris, 1565. He had no 
 very clear idea as to the origin of these objects, some of which he 
 thought might be remains of plants or animals, while others he 
 regarded as more probably produced by some inorganic process, 
 as minerals and ores are formed. 
 
4.6 Part attributed to Noah's Flood 
 
 these exquisitely designed but deceptive pieces of 
 mineral matter, with no apparent object unless to 
 puzzle and disconcert the mind of frail humanity. 1 
 
 If they refused to accept the latter alternative, they 
 found themselves face to face with the dogmas of the 
 Church and the consequences of professing disbelief 
 in them. The only escape from the dilemma which 
 then presented itself to such orthodox minds was to 
 have recourse to the Deluge of Noah. This event was 
 at that period regarded as having been a world-wide 
 catastrophe when, according to the sacred narrative, 
 " the fountains of the great deep were broken up, and 
 the windows of heaven were opened." For those 
 writers especially who had little or no personal acquain- 
 tance with the actual conditions of the problem, who 
 did not realise the orderly manner in which the fossils 
 are disposed, layer upon layer, for thicknesses of 
 many thousand feet in the solid rocks of the land, 
 the doctrine of the efficiency of the Flood offered a 
 welcome solution of the difficulty. They had no con- 
 ception of the physical impossibility of accumulating all 
 
 1 It is almost incredible how long some of these ignorant beliefs 
 lasted, and what an amount of argument and patience had to be 
 expended in killing them. I have been told that even within the 
 last century a learned divine of the University of Oxford used to 
 maintain his opinion that the fossils in the rocks had been purposely 
 placed there by the devil, in order to deceive, mislead and perplex 
 mankind. On the other hand, an opinion of a contrary tendency 
 was promulgated in the latter half of the previous century by a 
 Swiss naturalist, Bertrand, who suggested that the fossil plants and 
 animals had been placed there directly by the Creator, with the 
 design of displaying thereby the harmony of His work, and the 
 agreement of the productions of the sea with those of the land. 
 
The Dilumalists 47 
 
 the fossiliferous formations of the earth's crust within 
 the space of one hundred and fifty days during which 
 a the waters prevailed upon the earth, and all the high 
 hills that were under the whole heaven were covered." 
 It was enough for them to obtain warrant from Scrip- 
 ture that, since the creation of animal life, the dry 
 land had been submerged, and to adduce evidence 
 from the rocks which they could claim as striking 
 corroboration of the truth of the biblical story. Hence 
 the " diluvialists," or those who claimed the Deluge 
 as a leading geological event in the history of the 
 earth, formed for many years a powerful body of 
 controversialists, who owed their influence and popu- 
 larity more to the impression that they were the 
 champions of orthodoxy than to the convincing nature 
 of their reasoning. 
 
 There could not, however, fail to be some observers 
 who, after making themselves acquainted with the 
 fossiliferous strata, found it impossible to believe that 
 such piles of rock, crowded with a succession of organic 
 remains, could have been the work of a transient 
 inundation such as Noah's Flood confessedly was. 
 Some of these men, struck with the rapidity with 
 which detrital materials can be accumulated on the 
 surface of the earth by volcanic outbursts, imagined 
 that the stratified rocks might have been formed by 
 the operation of active volcanoes. The volcanic 
 eruptions of Italy and the Aegean Sea had greatly 
 impressed the minds of Italian writers, who felt that 
 if, as in the case of Monte Nuovo on the shore of 
 the bay of Naples in year 1538, a hill, nearly 500 
 feet high, could be piled up in two days around a 
 
48 Supposed Co-operation of Volcanoes 
 
 volcanic vent, it was at least conceivable that the 
 whole of the fossiliferous formations might have 
 been deposited by the same agency during the last 
 6000 years. So vague and inaccurate was the know- 
 ledge of rocks at that time, that those who started 
 this notion seem to have had no suspicion of how 
 entirely different in character and origin the ordinary 
 fossiliferous formations of the earth's crust are from 
 volcanic productions. Several generations had still to 
 pass, and detailed observations on stratified rocks had 
 to be laboriously made in many countries, before the 
 truth could be finally established that the fossiliferous 
 formations, many thousand feet in thickness, contain 
 a long record of geographical changes on the face 
 of the globe, and of a marvellous succession of organic 
 types which required a vast series of ages for their 
 evolution. 
 
 During the sixteenth, seventeenth and a great part 
 of the eighteenth century, the controversy over organic 
 remains and the part played by the Flood, while 
 keeping alive an interest in the subject, undoubtedly 
 hindered the advance of rational conceptions of the 
 fundamental facts of geological history. It was sin- 
 gularly unfortunate for the progress of this branch 
 of science that it should have aroused such ecclesias- 
 tical antagonism. For the true modern spirit of 
 observation and experiment had long been abroad and 
 at work in other branches of scientific inquiry wherein 
 the Church saw no danger, and where churchmen were 
 often among the foremost leaders. The necessity for 
 a close scrutiny of Nature, as the basis of sound deduc- 
 tion, had for generations been recognised by some of 
 
Advice of Severinus 49 
 
 the more thoughtful minds before it was developed 
 into a system by Bacon. Even as far back as the 
 latter half of the sixteenth century, the method of 
 practical research, as opposed to mere book-knowledge 
 and theory, had been advocated even for the investi- 
 gation of the rocky part of the earth. It was pro- 
 claimed, in no uncertain voice, by the learned and 
 versatile Dane, Peter Severinus, who counselled his 
 readers thus : " Go, my sons, sell your lands, your 
 houses, your garments and your jewelry; burn up 
 your books. On the other hand, buy yourselves 
 stout shoes, get away to the mountains, search the 
 valleys, the deserts, the shores of the sea, and the 
 deepest recesses of the earth ; mark well the distinc- 
 tions between animals, the differences among plants, 
 the various kinds of minerals, the properties and 
 mode of origin of everything that exists. Be not 
 ashamed to learn by heart the astronomy and terres- 
 trial philosophy of the peasantry. Lastly, purchase 
 coals, build furnaces, watch and experiment without 
 wearying. In this way, and no other, will you 
 arrive at a knowledge of things and of their pro- 
 perties." l The modern spirit of investigation in 
 natural science could not be more clearly or cogently 
 enforced than it was by this professor of literature 
 and poetry, of meteorology and of medicine, in the 
 year I57I. 2 
 
 1 Petrus Severinus, Idea Medecinae Philosophicae, 1571, p. 73, cap. 
 vii. De principiis corporum (cited by D'Aubuisson). 
 
 2 It is curious to find a parallel passage to this extract written 
 a hundred years later by Robert Hooke. He declared that, in 
 spite of all the knowledge that had been acquired respecting the 
 
50 Leonardo da Vinci 
 
 A brief survey of the progress of inquiry in Italy 
 will supply the best illustration of the slow advance 
 which was made in the demolition of long estab- 
 lished prejudice, and in paving the way for the ulti- 
 mate establishment of a philosophical conception of 
 the past history of the earth. One of the earliest 
 observers whose opinions have been recorded was the 
 illustrious painter, architect, sculptor, and engineer 
 Leonardo da Vinci (1452-1519). His attention hav- 
 ing been aroused by the abundantly fossiliferous nature 
 of some of the rocks in northern Italy, in which 
 canals were cut, he concluded that the shells con- 
 tained in these rocks had once been living on the 
 sea-floor, and had been buried in the silt washed off 
 the neighbouring land. He ridiculed the notion that 
 they could have been produced by the influence of 
 the stars, and he asked where such an influence 
 could be shown to be at work now. But he pointed 
 out that besides the shells, there were at various 
 heights, terraces of gravel composed of materials that 
 
 world we inhabit, an adequate natural history of the earth could 
 hardly be prepared until "after some ages past in making collections 
 of materials for so great a building, and the employing a vast number 
 of hands in making this preparation." He instanced the various 
 kinds of observers required and the methods and instruments to be 
 employed by them, " as by fire, by frost, by menstruums, by mixtures, 
 by digestions, putrefactions, fermentations, and petrifactions, by 
 grindings, brusings, weighings and measuring, pressing and con- 
 densing, dilating and expanding, dissecting, separating and dividing, 
 sifting and streining ; by viewing with glasses and microscopes, 
 smelling, tasting, feeling, and various other ways of torturing and 
 wracking of natural bodies, to find out the truth or the real effect, 
 as it is in its constitution and state of being." " Discourse of 
 Earthquakes," Posthumous Works, p. 279. 
 
Fracastoro 5 1 
 
 had evidently been rounded and accumulated by 
 moving water. 
 
 The discussion received a fresh impetus from the 
 abundance and variety of the organic remains in the 
 blocks of stone brought for the repair of the Citadel 
 of San Felice at Verona, in the year 1517. In the 
 midst of the keen discussion that arose over these 
 fossils, the learned men of the country were con- 
 sulted, including Fracastoro (1483-1553) who after 
 being Professor of Philosophy at Padua had returned 
 to his native city, Verona, to practice there as a 
 physician. When various theories had been pro- 
 pounded, he announced his own opinion that the 
 shells could never have been left by the Mosaic 
 deluge, which he maintained had only been a tem- 
 porary inundation, caused by heavy rains, and would 
 have scattered the shells over the surface of the 
 ground, instead of burying them deep within the 
 strata that form the mountains whence the stones 
 had been quarried. He showed the absurdity of 
 attributing such organised forms to any imaginary 
 plastic force, and insisted that the fossils were 
 undoubtedly at one time animals that lived and 
 multiplied where their remains are now found, and 
 therefore that the mountains have been successively 
 uplifted above the sea. 1 
 
 Cardano (1552) pointed to fossil shells as certain 
 
 1 G. Brocchi, Conchologia Fossile Subapennina, Vol. i., " Discorso sui 
 Progress! dello studio della Conchologia Fossile in Italia," p. v. This 
 essay contains a valuable summary of the progress of the science of 
 fossil shells in Italy from the year 1300 down to 1810. The work 
 in two quarto volumes was published in 1814. 
 
52 Cardano, Mattioli, Falloppio, Mercati 
 
 evidence that the sea once covered the sites of the 
 hills. His contemporary, Mattioli, on the other 
 hand, supported the old figment of the materia 
 pinguis, though admitting that porous bodies, such 
 as the bones and shells so abundant in Italy, might 
 be turned into stone by being permeated by a petrify- 
 ing juice. He is said to have been the first writer 
 who published a reference to the fossil fishes of Monte 
 Bolca. The skilful anatomist Falloppio (1557), when 
 he met with bones of elephants, teeth of sharks, shells 
 and other fossils, refused to admit them to be any- 
 thing but earthy concretions, because he deemed that 
 to be a simpler solution of the problem than to 
 suppose that the waters of the Deluge could have 
 reached as far as Italy. Aristotle had decided against 
 any universal flood, and the authority of this philo- 
 sopher was then about as potent as that of Holy 
 Writ. So much did Falloppio lie under the influ- 
 ence of this prejudice, that he thought it not unlikely 
 that the potsherds of Monte Testaceo at Rome 
 were in like manner natural productions of the 
 earth. 
 
 An important mineral collection, containing many 
 fossil shells, which had been gathered together in 
 the Vatican by Pope Sixtus V., was described and 
 excellently figured by Mercati (1574) who, however, 
 with all these well preserved organisms under his 
 eyes, denied their true organic nature, and came to 
 the conclusion that they were mere stones that had 
 assumed their present shapes under the influence of 
 the celestial bodies. It is worthy of notice that 
 another collection of natural history objects which, 
 
Olivi, Cesalpino, Steno 53 
 
 in the latter half of the same century had been 
 formed at Verona, was described by Olivi (1584) who 
 regarded the fossil organisms as mere sports of Nature. 
 Cesalpino (1566) who had distinguished himself as 
 a botanist, turned in his later years to mineral studies, 
 and wrote a volume De Metallicis, which may still 
 be usefully consulted for information on the stones 
 and ores of Italy. He recalled attention to the true 
 doctrine regarding fossil shells, which he looked 
 upon as organisms that had been left by the retir- 
 ing sea, and had been turned into stone by the 
 petrifying influence of the surrounding rock. Majoli 
 suggested that fossil shells on the land had been 
 ejected from the sea-floor by submarine volcanic ex- 
 plosions. 
 
 In the crowd of Italian writers who took part in this 
 long controversy, by far the most illustrious was Nicolas 
 Steno (1631-1687). Born in Copenhagen, he studied 
 medicine and took his degree there, afterwards passing 
 to Leyden and then to Paris, where he remained two 
 years, attaining great distinction by his discoveries in 
 human anatomy. He next travelled through Austria 
 and Hungary, and eventually settled in Florence where, 
 at the age of thirty-six, he was appointed physician 
 to the Grand Duke Ferdinand II. Not long there- 
 after, reflecting on the arguments which had been 
 put before him by Bossuet in Paris, he abjured the 
 Lutheran protestantism in which he had grown up, and 
 became a member of the church of Rome. His 
 European reputation led to repeated invitations being 
 sent to him from King Christian V. of Denmark to 
 accept the Chair of Anatomy in Copenhagen. To 
 
54 S tends Career 
 
 these solicitations he at last yielded, but although he 
 had full authority to exercise the rites of Roman 
 Catholicism, he now encountered so many unpleasant- 
 nesses in the Protestant community of his native city 
 that he finally quitted his fatherland, and returned to 
 Florence, where he was entrusted with the education 
 of the son of the Grand Duke Cosmo III. Gradually 
 becoming entirely devoted to a religious life, he took 
 orders and in 1677 was named Bishop of Heliopolis 
 and Vicar Apostolic in the north of Europe. He 
 thereafter employed his leisure in composing a series of 
 theological works. But it is upon the value of his 
 anatomical and geological writings that his fame mainly 
 rests. In 1667, soon after first settling in Florence, he 
 published the anatomy of the head of a dog-fish and 
 discussed the question whether the u glossopetrae," 
 or sharks' teeth, found in the rocks, belonged to such 
 fishes, or were mere mineral concretions, produced by 
 some process within the stone in which they lie. 
 Though he inclined to believe them to be truly of 
 organic origin, his statements were made with so much 
 timid reservation as to show how cautious even the 
 acutest intellects were constrained to be in touching 
 on any subject likely to rouse the orthodox prejudices 
 of the age. Two years afterwards, however, having 
 meanwhile enlarged his acquaintance with the rocks 
 and fossils of Northern Italy, he proclaimed with 
 frank boldness his conviction that the fossils were 
 once living things, and that they and the strata con- 
 taining them revealed a record of part of the history 
 of the earth. 
 
 In 1669 there appeared in Florence his treatise 
 
S tends Doctrines 55 
 
 De Solido intra soliaum naturaiiter contento^ which must 
 be regarded as one of the landmarks in the history 
 of geological investigation. It was meant to be intro- 
 ductory to a fuller work on the same subject, but 
 this expansion was never written. The following digest 
 of the contents of the treatise will show how far Steno 
 had advanced beyond any of his predecessors or con- 
 temporaries, and how modern and familiar some of 
 his original views now appear. 
 
 The strata of the earth are such as would be laid 
 down in the form of sediment from turbid water. 
 The objects enclosed in them, which in every respect 
 resemble plants and animals, were produced exactly 
 in the same way as living plants and animals are pro- 
 duced now. Where any bed encloses either fragments 
 of another, and therefore older, bed, or the remains 
 of plants or animals, it cannot be as old as the time of 
 the Creation. If any marine production is found in 
 any of these strata, it proves that at one time the sea 
 has been present there ; while, if the enclosed remains 
 are those terrestrial plants or animals, we may suspect 
 the sediment to have been laid down on land by some 
 river or torrent. 
 
 Similarity of composition in a series of strata proves 
 that the fluid from which the sediment was deposited 
 continued to be unaffected by other fluids coming from 
 other directions at different times : on the other hand, 
 a diversity in the character of the strata points either to 
 a commingling of different kinds of fluids, bearing 
 divers sediments, and caused perhaps by violent winds 
 and rains, or to a diversity in the composition of the 
 sediment, of which the heavier materials would first 
 
56 Stends Doctrines 
 
 sink to the bottom. The presence of coals, ashes, 
 pumice, bitumen or burnt substances shows the former 
 neighbourhood of some subterranean fire. 
 
 Steno established by direct observation some im- 
 portant axioms in stratigraphy. Every stratum, he 
 said, has been laid down upon a solid subjacent surface. 
 The lowermost strata must have become firm before 
 the uppermost were deposited. A stratum must 
 originally have terminated laterally against a solid body, 
 or else must have extended over the whole earth, so 
 that when the truncated ends or edges of strata are 
 exposed, we must either seek for evidence of their 
 former prolongation, or for the solid surface against 
 which they ended and which kept their materials from 
 slipping down. 1 As each bed at the time of its for- 
 mation was covered only with fluid, when the lowest 
 member of a series was laid down none of those 
 above it had yet been deposited. 
 
 The bottom of a series of strata necessarily conforms 
 to the irregularities of the surface on which it has been 
 deposited, but the upper surface, where the rocks are in 
 their original position, is parallel to the horizon or 
 nearly so. Hence all strata save the lowermost lie 
 between two plains approximately parallel with the 
 horizon. We must, therefore, conclude that strata 
 which are now vertical or inclined to the horizon were 
 originally nearly or quite horizontal. 
 
 That the edges or sides of the strata are laid bare 
 
 1 Steno had not realised the really lenticular character of all 
 sedimentary strata. But his conclusion that the truncated ends of 
 strata on a cliff-face point to the former continuation of the strata 
 beyond their present termination, is now a commonplace in geology. 
 
Stends Doctrines 57 
 
 in so many places, is to be ascribed to the operation 
 of running water which dissolves and transports earthy 
 substances to lower levels, and also to the action of 
 fire in dissipating solid bodies, and ejecting them above 
 ground. Thus precipices and channels are produced 
 on the surface of the earth, and caverns and tunnels 
 underneath. The strata are sometimes disrupted by 
 the sudden rise of subterranean exhalations ; at other 
 times they are broken up by the falling in of the 
 roofs of cavernous spaces inside the earth. Hence 
 they are thrown into a great variety of different 
 positions, being sometimes vertical, more often in- 
 clined at various angles, occasionally even bent into 
 arches. 
 
 This alteration in the original position of strata is 
 the real cause of the inequalities of the earth's surface, 
 such as mountains and plains. Some mountains have 
 also been produced by the outburst of fires from inside 
 the earth, whereby ashes and stones, together with 
 sulphur and bituminous substances, have been cast 
 forth. It is easy to perceive that all our mountains 
 have not been in existence since the beginning of 
 things. 
 
 Steno then proceeds to show that by the disruption 
 of the strata, outlets have been provided for the 
 escape of materials from inside the earth. Chief among 
 these are the springs of water that issue from the 
 hills. The cracks, fissures and cavities of the strata 
 have served as receptacles for most minerals, whether 
 introduced by vapours or otherwise. The question 
 of the origin of rock-crystal gives the author occasion 
 to discourse on the crystallography of this mineral, 
 
58 Steno on Fossils 
 
 and on the conditions in which crystalline substances 
 and ores have been produced within the earth. 
 
 Among the solids naturally enclosed within other 
 solids, Steno includes, as specially deserving of con- 
 sideration, fossil shells. His anatomical experience 
 enables him to declare with confidence that even if 
 no living marine shells had ever been seen, the 
 internal structure of the fossils demonstrates that they 
 once formed parts of living animals. He shows that 
 the fossils vary in character according to the extent 
 to which they have been petrified, some still retaining 
 their original composition and internal structures, others 
 having become entirely crystalline, as in those enclosed 
 in marble. He points out further that over and above 
 the predominant testaceous fossils, remains of many 
 other marine animals have been preserved in the strata, 
 such as teeth and vertebrae of dog-fishes, and all kinds 
 of fish-skeletons, while other strata have furnished the 
 skulls, horns, teeth and bones of land animals. 1 Against 
 those who found an insuperable difficulty in granting 
 the length of time required for all the vicissitudes 
 indicated by the strata and their fossils, Steno argues 
 that many of the organic remains found in the rocks 
 must be as old as the general Deluge, and he proceeds 
 to present a summary of what he conceives to have 
 
 1 It is curious to observe that Steno, while he recognised that teeth 
 and bones exhumed from the Agro Aretino were those of elephants, 
 did not realise that they too must be regarded as of prehistoric age. 
 He supposed them to be relics of the African elephants brought into 
 Italy by Hannibal. Brocchi has pointed out that after the battle of 
 the Trebbia the thirty-seven elephants which the Carthaginian general 
 had by the side of the Rhone were reduced to one single animal. 
 Op. cit. p. xv. 
 
Stenos Geological History 59 
 
 been the geological history of Tuscany. In this sum- 
 mary he illustrates the structure of the country by a 
 series of diagrams which show how clearly he had 
 grasped some of the fundamental principles of strati- 
 graphy. He recognises evidence of six distinct chrono- 
 logical phases, and is inclined to believe that the same 
 sequence will be found all over the earth. In the first 
 phase, the region was entirely submerged under the 
 sea, from which were deposited the strata containing 
 no remains of plant or animal life. In the second 
 phase, the land appeared as a dry plain, raised out 
 of the sea. In the third, the face of the earth was 
 broken up into mountains, crags and hills. In the 
 fourth, the land was once more submerged, perhaps 
 owing to a change in the centre of the earth's gravity. 
 In the fifth, the land reappeared and displayed wide 
 plains, formed apparently from the sediments carried 
 off from the land by the large rivers and by the 
 innumerable torrents which every day are extending 
 the shores and leaving new lands to be occupied by 
 fresh inhabitants. In the sixth and last phase, the 
 elevated plains were eroded by running water and 
 partly also by the co-operation of subterranean fire, so 
 as to be altered into channels, valleys and precipices. 
 Steno's treatise stands out far above all the writings 
 of his own or of previous generations in respect to the 
 minuteness and accuracy of his observations of Nature 
 and the originality and truth of most of the deductions 
 which he drew from them. He was the first clearly to 
 perceive that the strata of the earth's crust contain the 
 records of a chronological sequence of events, and that 
 the history of the earth must be deciphered from them. 
 
60 Vallisneri 
 
 He laid down for the first time some of the funda- 
 mental principles of stratigraphy. He recognised the 
 predominant influence of running water in carving out 
 the inequalities on the surface of the land. It is 
 true that he had no clearer notions than had obtained 
 for so many centuries regarding the true nature of 
 volcanic action, which he still regarded as due to the 
 subterranean combustion of carbonaceous substances. 
 He was hampered too by the prevailing theological 
 doctrine that the earth could not be more than some 
 6000 years old, and that the fossiliferous strata had 
 been mainly deposited during or since Noah's Deluge. 
 But his name must be enrolled high in the list of 
 those who by careful observation and deduction helped 
 to lay the foundations of modern geology. 
 
 Another illustrious observer in the geological domain 
 appeared in Italy when Steno, in his twenty-fifth year, 
 was rapidly rising into fame as an anatomist. Antonio 
 Vallisneri (1661-1730) became professor of medicine 
 in Padua. In the course of his journeys he had 
 opportunities of seeing much of the geology of his 
 native country and of forming a clearer conception 
 of the fossiliferous formations of the great central 
 mountain-chain than anyone had done before him. 
 He looked upon the shells in the rocks as remains 
 of mollusks that once undoubtedly lived in the sea. 
 In criticising the cosmological hypothesis of Wood- 
 ward (to be afterwards alluded to), he showed how the 
 Italian marine formations extend not only throughout 
 the peninsula but over a large part of Europe, and he 
 inferred that there was a time when the sea covered 
 the whole surface of the globe. He believed that it 
 
Anton-Lazzaro Moro 61 
 
 must have remained in that position for a long period, 
 and that its effects were altogether distinct from those 
 of the temporary Deluge of Noah. He wrote on the 
 origin of springs, maintaining that they do not come 
 from the sea, through subterranean passages in which 
 they lose the saline constituents of sea-water a belief 
 that had survived from antiquity and was still de- 
 fended as resting on scriptural evidence. He connected 
 springs with the structure of the rocks through which 
 they rise. 1 
 
 To one other notable Italian writer, who appeared 
 in the first half of the eighteenth century, reference 
 may here be made. Anton-Lazzaro Moro (1687-1740) 
 wrote a treatise De Crostacei e degli altri marini Corpi 
 che si truovano su Monti (Venice, 1740). The 
 grotesque speculations of Burnet and Woodward, 
 which will be more particularly referred to on a later 
 page, had already appeared in England and had found 
 their way into the Continent. A large part of Moro's 
 work is devoted to a destructive criticism of the 
 cosmogonies of these authors. He then proceeds to 
 discuss the possibility of explaining the position of 
 fossil shells in the mountains by reference to the 
 Noachian Deluge, and he dismisses this supposition as 
 untenable. He next inquires in what manner the 
 phenomenon can be explained from actual observa- 
 tions of natural processes. After giving an account 
 of the uprise of a new volcanic island in the Greek 
 Archipelago in the year 1707, of the appearance of 
 Monte Nuovo near Naples in 1538, and of the 
 
 1 Vallisneri's treatise Dei Corpi marini eke sui montl si trovano was 
 published at Venice in 1721, when its author was sixty years of age. 
 
6 2 Moro's Volcanic Theory 
 
 recorded eruptions of Vesuvius and Etna, and starting 
 with the proposition that the fossil shells are really 
 productions of the sea, he proceeds to unfold his 
 theory that the position of these shells, and the origin 
 of the rocks that enclose them, are to be assigned to 
 the operation of volcanic action. 
 
 In the beginning, he says, the globe was completely 
 covered with water, which was then fresh and perhaps 
 not more than 175 perches in depth. No prominences 
 diversified the smooth stony surface of the globe 
 which underlay the water. On the third day of 
 creation, however, when it pleased the Almighty to 
 reveal the solid earth, vast subterranean fires were 
 kindled, whereby the surface of stone was broken up, 
 and huge masses of it began to appear above the 
 water, so as to form the land and rnountains. These 
 disrupted masses, while rising or after they had risen, 
 and in some cases even before they appeared above 
 the water, were rent open by the violence of the 
 subterranean fires, and they discharged from their 
 orifices vast quantities of material, such as earth, sand, 
 clay, stones both solid and liquid, metals, sulphur, 
 salts, bitumen and every kind of mineral substance. 
 Part of this material flowed in river-like streams 
 down the sides of the mountains into the water 
 below, part fell in showers from the air into which 
 the ejected detritus had been hurled by the impetuosity 
 of the fire. The saline and bituminous ingredients 
 now began to give to the water the salt and bitter 
 taste which the sea has retained ever since, while the 
 other insoluble substances formed a new bottom above 
 the original stony surface. 
 
Mords Geological History 63 
 
 As the mountains increased in number by the out- 
 burst of new vents and continued to cast forth loose 
 materials, they gradually piled up on the sea-floor 
 many various strata which, especially near the eruptive 
 centres, eventually rose above the surface of the water. 
 The sea grew deeper or its surface rose higher, the 
 more its area was diminished. Fires also afterwards 
 burst out from below the submarine strata, and con- 
 tinued to eject fresh materials which formed new 
 strata that extended beyond those of earlier date. 
 New islands were formed, or were added to older 
 islands or to the continents. 
 
 As yet no plants or animals existed. But while the 
 water continued to grow more saline, plants began at 
 last to appear both in the sea and on land. Animals 
 too entered upon the scene, first in the sea, living in 
 the soft sand and among the debris cast out by the 
 mountains, and seldom wandering far from their 
 native places. The dry land became covered with 
 verdure and gave birth to terrestrial animals, finally 
 followed by the advent of man, who then took his 
 place as an inhabitant of this first and most ancient 
 land-surface. 
 
 In course of time, the same sequence of events 
 continuing, new mountains emerged from the bosom 
 of the earth, and like their predecessors vomited forth 
 fresh materials which were once more spread out over 
 the floor of the sea and the surface of the land. The 
 strata that were thus deposited in the sea would con- 
 tain marine productions, while those formed on the 
 land would preserve terrestrial remains, including 
 articles in metal, marble or carved wood as relics of 
 
64 Mords Orthodoxy 
 
 a human population. Some of these land-surfaces, 
 remaining long exposed to the open-air, were covered 
 with new strata, which when they differed in composi- 
 tion from those buried below them, would produce 
 plants and animals distinct from any of those which 
 had previously existed on the same sites. And since 
 the newer strata were not all laid down universally and 
 at the same time, but successively during the course 
 of centuries and at different seasons of the year, seeds 
 and fruits in mature and immature condition would 
 be entombed, as may be illustrated by many examples 
 that have actually been obtained from excavations in 
 which, at different levels, old soils represent inhabited 
 and cultivated surfaces of land. 
 
 Moro had to take care that his cosmogony did not 
 contradict but only supplemented the orthodox read- 
 ing of the first Chapter of the Book of Genesis. That 
 he succeeded in this aim is indicated by the imprimatur 
 at the end of his treatise, wherein the reformers of 
 studies testify that the book contains nothing contrary 
 to the Holy Catholic Faith, nor anything adverse to 
 Princes or to morals. Though he declined to adopt 
 the popular notion that the stratified rocks had been 
 formed during Noah's Flood, he still felt bound to 
 account for their deposition within the orthodox limits 
 of time. Public attention had been called to the 
 rapid accumulation of materials around active volcanic 
 vents, and Moro, availing himself of the original 
 suggestion of Majoli, boldly claimed that all the 
 stratified rocks which form the mountains consist of 
 materials successively erupted by volcanoes. He does 
 not seem to have ever studied the nature of true 
 
Rise of the Cosmogonists 65 
 
 volcanic products, nor to have been familiar with the 
 characteristic features of the limestones and other cal- 
 careous strata in which so large a proportion of fossil 
 organic remains is preserved. He added little to the 
 more luminous conceptions of Steno and Vallisneri. 
 But his influence was not inconsiderable in rousing 
 interest in the themes of which he treated. Nine 
 years after his book appeared, the Carmelite friar 
 Generelli, published an exposition of Moro's views, 
 which he placed in a clearer light than his master 
 had done. 
 
 The progress of geological inquiry in Europe during 
 the seventeenth century was marked by a character- 
 istic feature the development of a series of cosmo- 
 gonical systems, in which the only common basis of 
 speculation was the effort to account for the origin 
 of our globe and of our universe, in harmony with 
 the teaching of the Church. Science had not advanced 
 far enough to afford any firm basis for speculations of 
 this nature, and consequently the lack of data was in 
 too many cases supplied by wholly imaginary pictures 
 of the history of creation. The systems of cosmo- 
 gony thus framed, though some of them attained 
 considerable fame in their day, obstructed the pro- 
 gress of inquiry, inasmuch as they diverted attention 
 from the observation of Nature into barren contro- 
 versy about speculations. In vain did those who 
 had mastered some of the elementary truths about 
 the crust of the earth, oppose and even ridicule 
 these fanciful systems. The cosmogonists were not 
 disconcerted when phenomena were appealed to that 
 contradicted their theories, for they usually never 
 
66 The English Cosmogonists 
 
 saw such phenomena, and when they did, they easily 
 explained them away. Some of these writers were 
 divines, yet even when they were laymen they felt 
 themselves, down to the middle of the eighteenth 
 century, bound to suit their speculations to the re- 
 ceived interpretation of the books of Moses. Looking 
 back from our present vantage ground, it is difficult 
 to realise that even the little which had been ascer- 
 tained about the structure of the earth was not 
 sufficient to prevent some, at least, of the monstrous 
 doctrines of these theorists from being promulgated. 
 It was a long time before men came to understand 
 that any true theory of the earth must rest upon 
 evidence furnished by the globe itself, and that no 
 such theory could properly be framed until a large 
 body of evidence had been gathered together. 
 
 Nowhere did speculation run so completely riot as 
 in England with regard to theories of the origin and 
 structure of our globe. This craze reached its height 
 during the latter part of the seventeenth century. In 
 1 68 1 Thomas Burnet published in Latin his Sacred 
 Theory of the Earth. This work, republished in Eng- 
 lish, and favoured with the patronage of Charles II., 
 enjoyed a wide popularity and made some impres- 
 sion even on the Continent. It discoursed of the 
 original structure of our planet, and of the changes 
 which it was destined to undergo until " the consum- 
 mation of all things." As its title denotes, the book 
 was meant to support orthodox religion. With this 
 view, the Deluge was taken as one of the great events 
 in the history of the planet. Previous to that time, it 
 was asserted, there had been perpetual spring upon the 
 
Burnet, IVhiston, and Woodward 67 
 
 earth, but the wickedness of mankind led to a cata- 
 strophe in which the sun's rays split open the crust 
 of the earth, and allowed the central abyss of waters 
 to burst forth and overwhelm the inhabited lands. 
 
 William Whiston in his New Theory of the Earth 
 (1696) propounded almost more extravagant specula- 
 tions. He supposed that at the time of the Creation 
 the earth did not rotate on its axis, but that after the 
 Fall of Man it began to do so. When the years 
 had passed until the time of Noah, a comet on i8th 
 November B.C. 2349 sent its tail over the equator, 
 and caused a gigantic downpour of rain, while at the 
 same time the internal abyss of waters broke forth 
 and inundated the land. It was from the " chaotic 
 sediment of the flood " that the various stratified 
 formations of the earth's crust were deposited. 
 
 Another English writer who attributed similar 
 important effects to the Deluge was John Woodward, 
 familiarly remembered by the bequest of his collection 
 of specimens to the University of Cambridge, and by 
 the Professorship of Geology there which perpetuates 
 his name. He had an intimate acquaintance with the 
 stratified formations of a large part of England and with 
 their characteristic fossils. While firmly convinced that 
 these fossils were really the remains of once living 
 plants and animals, he could not free himself from 
 the incubus of the prevailing theological prejudice. 
 In his Essay towards a Natural History of the Earth 
 (1695) ne ran ged himself with those who maintained 
 that the shells in the rocks were relics of Noah's Flood. 
 He held a common belief of his day that the interior 
 of the earth was once full of water, which at the time 
 
68 Robert Hooke 
 
 of that calamity, when the fountains of the great 
 deep were broken up, burst forth and swept over the 
 face of the globe. The disrupted and disintegrated 
 crust was mingled with the diluvial waters, from which 
 the sediments ultimately settled down on the bottom 
 in the order of their gravity. By a curious perversity 
 of judgment, Woodward persuaded himself that the 
 fossils had followed the same rule and that the heaviest 
 were found in the lowest strata, the lightest in the 
 uppermost a statement afterwards sharply criticised 
 by Ray. 
 
 Woodward's most important contribution to science 
 is his catalogue of the fossils which in the course of 
 long years he had collected in England, and which 
 now form an interesting portion of the Sedgwick 
 Museum at Cambridge. It is entitled " An attempt 
 towards a Natural History of the Fossils of England 
 etc., or a Catalogue of English Fossils" in the collection 
 of J. Woodward M.D. 2 vols 1728-29. 
 
 Of a totally different stamp from the cosmogonists 
 above mentioned was the mathematician and natural 
 philosopher Robert Hooke (1635-1703), one of the 
 most brilliant, ingenious, and versatile intellects of 
 the seventeenth century. Among the many subjects 
 to which he directed his attention and on which his 
 remarkable powers of acute observation and sagacious 
 reflection enabled him to cast light, some of the more 
 important problems of geology must be numbered. 
 As "Curator of Experiments" to the Royal Society, 
 and as one of the most active members of that body, 
 he had frequent opportunities of discoursing on the 
 topics which engaged his thoughts. From time to 
 
Hooke s Discourses 69 
 
 time he lectured on what would now be called physical 
 geography and geology. Such lectures as remained 
 in manuscript after his death were collected and 
 published in a folio volume of posthumous works 
 (London, 1705). The largest section of this book 
 consists of c< Lectures and Discourses of Earthquakes 
 and Subterraneous Eruptions, explicating the Causes 
 of the Rugged and Uneven Face of the Earth ; and 
 what Reasons may be given for the frequent finding 
 of Shells and other Sea and Land Petrified Substances 
 scattered over the whole Terrestrial Superficies." 1 
 
 Beginning with an account of " figured stones " 
 or organic remains imbedded in rocks, illustrated with 
 well-drawn figures of fossils, Hooke discusses the 
 difficulties met with in explaining the nature and origin 
 of these objects, and proves in a series of propositions 
 that the fossils are either the organisms themselves 
 turned into stone, or the impressions left by them ; 2 
 that a great part of the surface of the earth has been 
 transformed since the Creation, sea being turned into 
 
 1 Though the volume did not appear until after the author's death, 
 the first discourse seems to have been given in 1 668. 
 
 2 The truly organic nature of the fossils is the subject of a 
 careful demonstration by Hooke, in the course of which he 
 remarks " that it is contrary to all the other acts of Nature, that 
 does nothing in vain, but always aims at an end, to make two 
 bodies exactly of the same substance and figure, and one of them 
 to be wholly useless, or at least without any design that we 
 can with any plausibility imagine." The fossils "if they were 
 not the shells of fishes, will be nothing but the sportings of 
 Nature, as some do finely fancy, or the effects of Nature idely 
 mocking herself, which seems contrary to her gravity." Posthumous 
 Works, p. 318. 
 
70 Hookes Geological J^iews 
 
 land, land into sea, mountains into plains and plains 
 into mountains ; that most places where fossil plants 
 or animals have been found have lain under water, 
 " either by the departing of the water to another part 
 or side of the earth, by the alteration of the centre of 
 gravity of the whole bulk, which is not impossible ; 1 
 or rather by the eruption of some kind of subterraneous 
 fires, or earthquakes whereby great quantities of earth 
 have then been raised above the former level of those 
 parts " ; that not improbably the tops of the highest 
 mountains in the world have been under water, these 
 elevations of the land having most probably been 
 the effects of some very great earthquake ; that the 
 greatest part of the inequalities of the earth's surface 
 may have been caused by u the subversion and 
 tumbling thereof by some preceding earthquakes " ; 
 that " there have been many other species of creatures 
 in former ages, of which we can find none at present ; 
 and that 'tis not unlikely also but that there may be 
 
 1 The possible change of the earth's centre of gravity is fully 
 discussed by Hooke in several discourses. A passage in which the 
 idea is expressed gives a vivid picture of the philosopher's prescient 
 outlook in terrestrial physics. He conceives that a very great earth- 
 quake (using that word for any kind of displacement of the 
 terrestrial crust) might not impossibly alter the centre of gravity 
 and also the axis of rotation. He thinks that the diurnal rotation 
 and annual revolution of the globe may once have been made in 
 a much shorter time than now, so that a day and a year at the 
 beginning of the world would not have been so long as now 
 when these motions have become slower. He further suggests 
 that " the fluid medium in which the earth moves, may after a 
 thousand revolutions, a little retard and slaken that motion, and 
 if so, then a longer space of time will pass while it makes its 
 revolution now than it did at first." Op. dt. p. 322. 
 
Hooke on Fossils 71 
 
 diverse new kinds now, which have not been from 
 the beginning." 
 
 With regard to the inequalities of the earth's surface, 
 Hooke enters fully into the effects of the earthquakes 
 by which he thinks they have been produced. Some 
 earthquakes raise the earth's surface, either by 
 upheaval or by piling up " a great access of new 
 earth " ; others depress the surface : those of a third 
 type disrupt and subvert parts of the earth ; while 
 by a fourth class liquefactions, vitrifications, calcina- 
 tions, sublimations and other effects are produced. 
 He shows how universal is this active principle of 
 terrestrial change, no country in the whole world 
 having escaped being shaken sometime or other by 
 earthquakes. 
 
 Having demonstrated from organic remains that 
 the dry land must have lain for some time under 
 water, Hooke argues that this water could not have 
 been the Flood of Noah, which did not continue 
 long enough " for the production and perfection of so 
 many and so great and full-grown shells ; besides, the 
 quantity and thickness of the beds of sand with which 
 they are many times found mixed, do argue that 
 there must needs be a much longer time of the sea's 
 residence above the same, than so short a space can 
 afford." 1 The large size of some of the shells as 
 well as their resemblance in form to some of those 
 found in tropical seas leads him to ask whether it is 
 impossible that the South of England, where these 
 shells are found, may for some ages past have lain 
 within the Torrid Zone. Thus fossil organic remains 
 
72 Hooke on the Use of Fossils 
 
 were in Hooke's eyes not mere curiosities, but valuable 
 records of the past history of the earth. " I do 
 humbly conceive," he remarks, " (tho' some possibly 
 may think there is too much notice taken of such a 
 trivial thing as a rotten shell, yet) that men do 
 generally too much slight and pass over without 
 regard these records of antiquity which Nature have 
 left as monuments and hieroglyphick characters of pre- 
 ceding transactions in the like duration or transactions 
 of the body of the Earth, which are infinitely more 
 evident and certain tokens than anything of antiquity 
 that can be fetched out of coins or medals, or any 
 other way yet known, since the best of those ways 
 may be counterfeited or made by art and design, as 
 may also books, manuscripts and inscriptions, as all 
 the learned are now sufficiently satisfied, has often 
 been actually practised ; but those characters [fossil 
 shells] are not to be counterfeited by all the craft in 
 the world, nor can they be doubted to be, what they 
 appear, by any one that will impartially examine the 
 true appearances of them : And tho' it must be 
 granted that it is very difficult to read them and 
 to raise a chronology out of them, and to state the 
 intervalls of the times, wherein such or such cata- 
 strophies and mutations have happened ; yet 'tis not 
 impossible, but that much may be done even in that 
 part of information also." 1 
 
 Hooke does not appear to have formed any very 
 clear ideas either as to the causes of earthquakes or 
 the nature of volcanic action. He connects the two 
 classes of phenomena together, and in various places 
 
 J p. 411. 
 
John Ray 73 
 
 alludes to them as effects of " the general congregation 
 of sulphureous, subterraneous vapours." He thinks 
 that the observed greater frequency of earthquakes 
 and volcanoes on islands and sea-coasts may possibly 
 be due to " the saline quality of the sea- water which 
 may conduce to the producing of the subterraneous 
 fermentation with the sulphureous minerals there 
 placed." " These fermentations subjacent to the sea, 
 being brought to a head of ripeness, may take fire, 
 and so have force enough to raise a sufficient quantity 
 of the earth above it to make its way through the 
 sea, and there make itself a vent." " The foment or 
 materials that serve to produce and effect conflagra- 
 tions, eruptions or earthquakes, I conceive to be 
 somewhat analogous to the materials of gunpouder." 1 
 This philosopher had therefore advanced no further, 
 in regard to the hypogene agents in geology, than the 
 writers of antiquity and of the middle ages. 
 
 How far the ideas imposed by the prevailing 
 theological beliefs of the period could influence even 
 a man of eminent scientific ability is perhaps most 
 fully illustrated in the case of John Ray (1627-1705), 
 the ablest botanist and zoologist of his day, to whom 
 science has been indebted for some masterly contribu- 
 tions to its progress. With his wide sympathies for 
 Nature, he could hardly avoid entering the geological 
 field, and as he was a loyal and devoted member of 
 the Church of England, he could scarcely escape from 
 carrying with him more or less of the ecclesiastical 
 prejudices of his time. Where these prejudices were 
 not involved he could see things as they are, and draw 
 !pp. 421, 424. 
 
74 Ray's Geological Opinions 
 
 the natural inferences to which they lead. Thus he 
 entered fully and sagaciously into the theory of 
 springs, quoting his own experience at his country 
 home, and showing conclusively, in opposition to 
 Hooke, that it is not by dews condensed on the 
 mountains but by the water supplied by rain that 
 springs are fed. He watched, too, the effects of 
 running water, especially the manifest action of " rains 
 continually washing down and carrying away earth 
 from the mountains," and the destruction of the 
 shores by the perpetual working of the sea, and he 
 believed that in the end, by the combination of these 
 processes, the whole dry land might possibly be re- 
 duced below the sea-level. 1 
 
 When Ray came to discuss " formed stones," or 
 " sea-shells and other marine bodies found at great 
 distances from the shores," he was obviously no longer 
 free to do so untrammelled as to what conclusions 
 he might draw from them. He caustically criticises 
 Woodward's diluvial theory, remarking that he sus- 
 pected that author to have invented part of his theory 
 to solve supposed facts which are not generally true. 
 But though he had " spent many thoughts " on this 
 subject, he confesses that he could not fully satisfy 
 himself as to the nature and real origin of the 
 "formed stones." He balances the arguments for 
 and against their truly organic origin, seeming at one 
 moment to agree with those who regarded them as 
 
 1 Miscellaneous Discourses concerning the \Dissolution and Changes of the 
 World, by John Ray, Fellow of the Royal Society, London, 1692, 
 pp. 44-56, and Three Physico-Theological Discourses, 4th Edit., 1721, 
 pp. 89-114, 245. 
 
Ray on Rarthquakes and Volcanoes 75 
 
 "originally formed in the places where they are now 
 found by a spermatic principle," and yet unable to 
 resist the evidence that " these bodies owe their 
 original to the sea, and were sometimes the shells or 
 bones of fishes." 
 
 As regards hypogene phenomena Ray made no 
 advance. Thus he says : " That the cause of earth- 
 quakes is the same with that of thunder, I doubt 
 not, and most learned men are agreed ; that is, 
 exhalations or steams set on fire, the one in the 
 clouds, the other in the caverns of the earth." * 
 Volcanoes are regarded by him as connected with 
 earthquakes and due to the heating of " steams or 
 damps " within subterranean caverns " by a collucta- 
 tion of parts," whereby combustible materials in the 
 hollows of the mountains are set on fire and the 
 metals and minerals are melted down, while if water 
 enters these caverns " it mightily increaseth the raging 
 of the mountain, for the fire by the help thereof 
 throws up earth and stones, and whatever it meets 
 with." 2 Yet Ray, while he "utterly disallowed and 
 rejected" Descartes' theory of the origin of the earth, 
 was not unwilling to admit the existence of a central 
 fire, more especially as it would presumably support 
 the references to Hell in the Bible. But he does not 
 appear to have ever thought of connecting this pos- 
 sible central fire with the operations of active volcanoes. 
 
 That Ray, in spite of his instinct as a naturalist 
 
 and keen observer, should have been shaken in his 
 
 opinion that the fossils in the rocks are the remains 
 
 of once living things, can hardly surprise us when we 
 
 1 Three Physico-Tkcological Discourses, p- 258. 2 p. 268. 
 
j6 Martin Lister on Fossils 
 
 remember that the two men who in all England had 
 the most extensive acquaintance with fossils refused 
 to admit them to be of organic origin. Martin 
 Lister (1638-1712), an active and able fellow of the 
 Royal Society, published a remarkable history of all 
 the shells then known, with accurate plates, which 
 included not only the living species but many fossil 
 forms placed with them for comparison. Yet strange 
 to say, he stoutly refused to believe that the fossils 
 had ever belonged to living creatures. " For our 
 English inland quarries," he said, " I am apt to think 
 there is no such matter as petrifying of shells in 
 the business ; but that these cockle-like stones are 
 everywhere as they are at present, lapides sui generis, 
 and never were any part of an animal," that they 
 " have no parts of a different texture from the rock 
 or quarry whence they are taken, that is, that there 
 is no such thing as shell in these resemblances of 
 shells." He admitted that some of the fossils are 
 like Murices, or Tellinae or Turbines, etc., yet he had 
 never met with any one of them on any English 
 sea-shore or fresh- water ; whence he concluded a that 
 they were not cast in any animal-mold, whose species 
 or race is yet to be found in being at this day." 
 Having made up his mind with the evidence fully 
 before him, it was only natural that, as Woodward 
 tells us, " he bravely continued to the last firm and 
 unshaken in his opinions." 
 
 Lister made the ingenious suggestion that volcanic 
 eruptions may be due to the subterranean decomposi- 
 tion of iron-pyrites. Even among those who from 
 l Phil. Trans, vol. v. (1671), p. 2282. 
 
Lister, Plot, Lhuyd 77 
 
 time immemorial had regarded volcanic action as 
 arising from the combustion of inflammable materials 
 in the crust of the earth, much difficulty and divergence 
 of opinion existed respecting the active cause that 
 set these materials on fire. Lister's suggestion had 
 the merit of being a vera causa, from which un- 
 doubtedly the spontaneous combustion of carbonaceous 
 strata has often arisen. 
 
 To geologists perhaps not the least memorable of 
 Lister's contributions to the progress of science was 
 a proposal made by him for the first time for the 
 construction of what we now call geological maps. 
 This subject will be more particularly referred to in 
 Chapter XIV. 
 
 Robert Plot in his Natural History of Oxfordshire 
 (1677) described Nature's "extravagancies and defects, 
 occasioned either by the exuberance of matter or 
 obstinacy of impediments, as in monsters ; and then 
 lastly as she is restrained, forced, fashioned or deter- 
 mined by artificial operations." Though he gave a 
 map and sixteen beautifully engraved plates which 
 included representations of fossils, he stated seven 
 reasons for rejecting the idea that the fossils " owed 
 their form and figure to the shells of the fishes they 
 represent " and for concluding that these objects or 
 c< formed stones " must be regarded as u lapides sui 
 generis, naturally produced by some extraordinary plastic 
 virtue, latent in the earth, or quarries where they are 
 found." ! 
 
 With these writers may here be included the Celtic 
 scholar and antiquary, Edward Lhuyd (1660-1709) who 
 
 1 O/. clt. 2nd Edit. (1705), p. 112. 
 
78 Edward Lhuyd 
 
 published a Latin treatise in which he gave excellent 
 plates of a thousand fossils preserved in the Ash- 
 molean Museum, Oxford. He was a valued corre- 
 spondent of Ray, who quotes him as suggesting that 
 the fossils enclosed within rocks might possibly be 
 " partly owing to fish-spawn received into the chinks 
 of the earth in the water of the Deluge," and as 
 speculating " whether the exhalations which are raised 
 out of the sea, and falling down in the rains, fogs, 
 etc., do water the earth, to the depth here required, 
 may not from the seminium or spawn of marine 
 animals, be so far impregnated with, as to the naked 
 eye invisible, animalcula (and also with separate or 
 distinct parts of them), as to produce these Marine 
 Bodies, which have so much excited our admiration, 
 and indeed baffled our reasoning, throughout the 
 globe of the earth." 1 
 
 1 Ray, Three Physico-Theological Discourses (1721) p. 190. In the 
 long letter from which these sentences are taken Lhuyd brings 
 forward a number of shrewd arguments against ascribing fossil 
 shells and plants to Noah's Flood. 
 
CHAPTER III 
 
 SCIENTIFIC Cosmogonists Descartes, Leibnitz. Speculations of De 
 Maillet and Buffon. Early illustrated works on fossil plants and 
 animals Lang, Scheuchzer, Knorr, Walch, Beringer. 
 
 FROM the middle of the seventeenth to the middle of 
 the eighteenth century there appeared at intervals on 
 the Continent a series of cosmogonists of a very dif- 
 ferent stamp from those alluded to in the last chapter. 
 They were men who took a broad view of the world 
 and endeavoured to trace its origin and progress in the 
 light of what was then known of the laws of Nature. 
 The earliest of these illustrious writers was the dis- 
 tinguished philosopher Descartes (1596-1650) who, 
 in his Philosophiae Principia, published in 1644, gave 
 an exposition of what he conceived to have been 
 the origin and history of our globe. He supposed 
 the various planetary bodies to have been originally 
 glowing masses like our sun. The earth in his view 
 consists of three distinct regions. In its centre lies 
 a nucleus consisting of incandescent self-luminous 
 matter, like that of the sun. The middle zone is 
 composed of an opaque solid substance which was at 
 first very liquid. The outer region, comprising all the 
 materials of which we have actual cognisance, consists 
 
8o Cosmogony of Descartes 
 
 of the debris of the clouds or spots which, like those 
 of the sun, gathered on the surface of the globe while 
 still an intensely hot body. These spots were no 
 doubt again and again melted down as they formed, 
 until the whole globe had cooled sufficiently to allow 
 them to aggregate into a solid external crust. The 
 outer region of the planet, as the earth drew towards 
 the sun, separated into different portions that arranged 
 themselves one above another, according to their relative 
 densities, the atmosphere being uppermost, then the 
 water, while below these the more solid matter took 
 the form of an outer layer of stone, clay, sand and 
 mud, and an inner more solid and heavy layer whence 
 all the metals come. Descartes supposed that the heat 
 and light of the sun could penetrate into the innermost 
 parts of the earth and there, during day and summer, 
 in the early stages of the planet's history, exerted so 
 potent an influence as to lead to the rupture of the 
 outer crust, of which some projecting portions rose 
 above the waters and formed land. 
 
 This philosopher further suggested that certain 
 exhalations from the inner parts of the earth turn into 
 oil, but when they are in a state of violent motion and 
 in that condition enter cavities or fissures which pre- 
 viously contained air, they pass into a heavy thick 
 smoke, like that of a newly extinguished candle. 
 When a spark of fire is excited in these places the whole 
 of the smoke bursts into flame, and becoming suddenly 
 rarefied presses with great violence against its con- 
 taining walls, especially when it includes a quantity 
 of volatile salts and spirits. Hence arise earthquakes. 
 It sometimes happens also that the flame which causes 
 
Leibnitz 8 1 
 
 earthquakes breaks open the top of a mountain and 
 issues thence in great volume, hurling forth much earth 
 mingled with sulphur or bitumen. These mountains 
 may continue to burn for a long time, until all the 
 sulphur or bitumen is consumed. Descartes thought 
 that the subterranean fires might be kindled by the 
 spirits inflaming the exhalations, or by the fall of 
 masses of rock and the consequent sparks produced by 
 their friction or percussion. 
 
 Still more memorable than the cosmological specu- 
 lations of Descartes were those of the philosopher 
 Leibnitz (1646-1716), whose capacious mind embraced 
 every department of human knowledge, and whose 
 acute and original genius threw new light into each. 
 Among the subjects that engaged his thoughts was the 
 problem of the origin and early history of our globe, 
 regarding which he propounded views that have been 
 accepted by the physicists of our own day. A summary 
 of these opinions was first promulgated by him in a 
 communication to the Acta Eruditorum of Leipzig, 
 published in 1693, but the fuller statement contained 
 in his remarkable treatise, the Protogaea, did not appear 
 till 1749, thirty-three years after his death. Like 
 Descartes, he believed that our planet was once a 
 smooth incandescent molten globe, which has ever 
 since been cooling, contracting and becoming rugose 
 on the surface. When the temperature of the outer 
 parts had sufficiently fallen, a glassy and slaggy crust 
 began to form on the outside, portions of which he 
 supposed to be recognisable in the primitive crystalline 
 rocks, such as granite and gneiss. Out of the vaporous 
 atmosphere, as the whole planet cooled, the water 
 
82 Cosmogony of Leibnitz 
 
 condensed into liquid form and made the ocean, which 
 by washing the debris of the crust, dissolved out the 
 soluble ingredients and became salt. As the thickness 
 of the crust increased, its solidification was accompanied 
 by the formation of immense cavities containing air 
 or water, the roofs of which, when they sank down, 
 would form valleys, while the other more solid parts 
 would rest like columns and give rise to mountains. 
 By the disruption of the crust, whether owing to its 
 weight or to gaseous explosions, vast inundations would 
 be produced which rushing over the face of the globe 
 would sweep a great amount of sediment together 
 and allow of the accumulation of sedimentary forma- 
 tions. Thus the face of the earth would be often 
 renovated until, as the various disturbing forces quieted 
 down and become more equable in their action, a 
 more stable condition of things (consistentior rerum 
 status] arose. In these reactions Leibnitz clearly re- 
 cognised the working of the two great classes of 
 geological causes, in the first place the internal 
 heated nucleus whence igneous rocks proceed, and in 
 the second place, the superficial waters whereby hollows 
 are eroded on the earth's surface and sedimentary rocks 
 are formed. 
 
 As if he considered their obvious connection with 
 the internal fire a sufficient explanation of their occur- 
 rence, Leibnitz passes briefly over the subject of 
 earthquakes and volcanoes. Yet he seems still to 
 entertain the old notion that actual combustion takes 
 place as part of these subterranean disturbances, for 
 in alluding to the underground fires that feed vol- 
 canoes, he mentions the deposits of stone-coal and 
 
Leibnitz on Fossils 83 
 
 sulphurous materials, native sulphur, and springs of 
 naphtha, and remarks "it is not unreasonable to 
 believe that since the Deluge there have been partial 
 fires, the date of which is not known, but which 
 occurred at a time when combustible substances were 
 more plentifully distributed in the thickness of the 
 earth than they are now." 
 
 A considerable part of the Protogaea is devoted to 
 a discussion of the evidence from organic remains 
 enclosed in the sedimentary formations. In showing 
 how perfectly and in what minute detail the struc- 
 ture of fishes and other organisms is reproduced in 
 these fossils, Leibnitz ridicules the absurdity of calling 
 them " sports of Nature," and points out how much 
 more willingly we should admit the operation of an 
 obvious and regular cause than a mere game of chance 
 or other fanciful suggestion, under which the conceited 
 ignorance of the learned had taken shelter. He insists 
 on discriminating between the polygonal forms of 
 crystals and the shapes of fossils, which had all been 
 classed as arising from the same plastic force, and he 
 complains of the facile credulity which could bring men 
 not only to confound these utterly distinct things, but 
 to believe that Nature could have manufactured within 
 the rocks historical and mythological pictures, such as 
 Apollo and the Muses in veins of agate, the pope and 
 Luther in the stone of Eisleben, and sun, moon and 
 stars in marble. 
 
 Leibnitz takes note of the astonishment expressed 
 by some writers that for many of the " figured stones " 
 no analogies had been discovered in the living world of 
 to-day, or at least in the regions where these objects are 
 
84 Benoit de Mail let 
 
 found. He asks in reply whether any one had yet 
 explored the depths of the ocean, or how many animals, 
 hitherto unknown, remained still to be discovered in 
 the New World. " Is it not to be presumed," he 
 enquires, "that in the great changes which the earth 
 has undergone a great many animal forms have been 
 transformed ?" After describing a number of instances 
 in which a succession of strata has been ascertained 
 to contain different platforms of organic remains, point- 
 ing to advances and retreats of the sea, he concludes his 
 treatise with these words : " Thus Nature fills for us 
 the place of history ; while on the other hand, our 
 history pays back to Nature this service, that it takes 
 care that her illustrious works, so far as we have been 
 able to perceive them, shall not remain unknown to our 
 posterity." x 
 
 We have now to notice the work of a writer of an 
 utterly different type from the two philosophers just 
 spoken of. Though hardly deserving to be regarded 
 as a man of science, Benoit de Maillet (1656-1738), 
 French diplomatist and traveller, was a keen and 
 shrewd observer of Nature, and his speculations were 
 not without their influence on the progress of geology. 
 In the course of his long life he saw much of the 
 countries bordering both sides of the Mediterranean 
 basin, and gathered together stores of information 
 regarding the physical aspect and historical changes 
 in the surface of these countries. Being led to 
 speculate on the probable origin and future fate of 
 this globe and its inhabitants, he arrived at conclu- 
 sions which were at least conspicuously unorthodox. 
 1 Protogaea, p. 86. 
 
The Telliamed 85 
 
 In committing them to paper he ingeniously contrived 
 to put them into the mouth of an Indian philosopher, 
 but even with this precaution he did not venture to 
 publish them, and his treatise only saw the light at 
 Amsterdam in 1748, ten years after his death. It 
 bore the title of Telliamed [his own name spelt 
 backwards] ou Entretiens dun Philosophe Indien avec 
 un Missionaire Fran^ais. 
 
 The main purport of the book is to demonstrate 
 that this globe was once completely surrounded with 
 water, which has been gradually disappearing and will 
 continue to diminish, until the planet is desiccated 
 and is finally burnt up by the outbreak of volcanic 
 forces from within. We cannot doubt, so the author 
 believed, that this globe is the work of the sea and 
 has been formed in its bosom, in the same way that 
 similar formations are even now deposited in its 
 waters. All mountains consist of sand, mud or 
 other sedimentary materials, and have been formed 
 by the sea. The oldest and highest are composed 
 of a simple and uniform substance, in which few 
 or no traces of animal life have been preserved. 
 As the sea, in its subsidence, laid bare the summits 
 of these earliest mountains, the waves beat on their 
 sides, and the materials of new mountains were thus 
 obtained, in which organic remains became increas- 
 ingly abundant. That the various sediments should 
 be arranged one above another in successive strata, 
 is shown to be what might be expected from the 
 action of the sea along its coasts and over its 
 bottom at the present time. Emphasis is laid on 
 the prodigious abundance of marine fossils from 
 
86 Telliamed on Retreat of the Sea 
 
 below sea-level up to the mountain tops as proof 
 of the former submergence of the land and of the 
 mode in which the rocks of the land have been 
 formed. The author sagaciously calls attention to 
 the fact that, instead of being indiscriminately huddled 
 together in the strata, the fossils are found to lie on 
 the planes of stratification, just as the shells and 
 other organisms of the present sea are strewn over 
 the surface of the sea-floor. 
 
 Telliamed, the Indian Philosopher, ridicules the 
 notion that these universal marine formations could 
 have been laid down by Noah's Flood, which he 
 affirms was a local and transient inundation. He 
 asserts that the valleys and other hollows of the 
 earth's surface have been scooped out by marine 
 currents during the sinking of the sea, leaving the 
 mountainous ridges standing up between them. The 
 diminution of the water is regarded by him as due 
 to evaporation, whereby the vapour is carried through 
 space to the extremity of the vortex wherein the 
 dust and the particles of water are once more con- 
 densed upon other globes. 
 
 Methods are described for measuring the rate of 
 the lowering of the sea-level, and as the result of ob- 
 servation it is estimated that the diminution amounts 
 to as much as three or four inches in a century, or 
 about three feet in a thousand years. A time will 
 come when the Black and Mediterranean seas will be 
 isolated into lakes, like the Caspian, and when the 
 Atlantic will be laid dry, save perhaps some restricted 
 remnant in its deeper part, while the rivers of the 
 Old and New World will mingle their waters together. 
 
Telliamed on Animal Evolution 87 
 
 Volcanoes, in the cosmogony of Telliamed, are due 
 to the combustion of the oils and fats of the various 
 animals entombed in the sediments of which the 
 mountains have been formed. These volcanoes, by 
 communicating with each other, will ultimately ex- 
 tinguish all life, and finally lead to the total con- 
 flagration of our globe, which will then become a 
 true sun, until having consumed all the combustible 
 material that maintained this prodigious heat, it will 
 once more cool down and become opaque. 
 
 But the most curious speculations of Telliamed 
 are those in which he discusses the problem of the 
 origin of the various races of animal life. He supposes 
 the plants and animals of the land to have been 
 derived from those of the sea. But the data which 
 he advances in support of his notions of evolution 
 seem to us now almost childishly absurd. He speaks 
 of rose-trees which had their blooms quite red when 
 they were taken out of the sea. He affirms that 
 there exist on land no walking, flying, or creeping 
 creatures which have not their analogues in the sea, 
 and that their transference from one region to the 
 other is not only probable but can be proved by 
 a vast number of actual examples. He illustrates 
 what he conceives to be the natural course of trans- 
 formation by picturing flying fishes which somehow 
 should fall among reeds or rushes and be unable to 
 resume their flight. Their exertions would increase 
 their aptitude to use their wings, but the dry air 
 would split these membranes and raise up the scales 
 of their bodies into a kind of down, the little fins 
 under their belly, which once helped them to swim, 
 
88 Buff on 
 
 would now become feet which would enable them ta 
 walk on the land. Then follows an account of seals, 
 sea-dogs, and the origin of man, wherein the author 
 states that he will scrupulously reject everything which 
 might be regarded as fanciful, and that he will confine 
 himself to well-attested and recent facts. He then 
 gravely recites a number of tales of mermen and 
 mermaids, of savage dumb men, like apes, of men 
 with tails, of giants and dwarfs, and he comes to 
 the conclusion that as all the species of mermen are 
 still unknown, it is not yet possible to trace from 
 which of them the various races of mankind have 
 been derived. He sees no difficulty in the transition 
 of men from the water to the air, and thinks that 
 this passage is easiest in polar regions, where probably 
 the transformation of mermen into ordinary men is 
 always most common. 
 
 The last and not the least eminent of the cos- 
 mogonists who may be cited in this retrospect is the 
 illustrious naturalist G. L. Leclerc de Buffon (1707- 
 1788) one of the great pioneers in science who figure 
 so conspicuously in the history of France. At first 
 he interested himself in physics and mathematics, but 
 gradually widened his outlook, and conceived broad and 
 profound ideas regarding the whole realm of Nature. 
 Endowed with a spirit of bold generalisation, and 
 gifted with a style of singular clearness and eloquence, 
 he was peculiarly fitted to fascinate his countrymen, 
 and to exercise a powerful influence on the scientific 
 progress of his age. He is the central figure in a 
 striking group of writers and observers who placed 
 France in the very front of the onward march of 
 
Buffons Theory of the Earth 89 
 
 science, and who laid some of the foundation-stones 
 of modern geology. 
 
 The introductory portion of Buffon's voluminous 
 Natural History was devoted to a Theory of the Earth. 
 Though written in 1744, it was not published until 
 1749. The author had meditated long and deeply on 
 the meaning of the fossil shells found so abundantly 
 among the rocks of the earth's crust, and had recog- 
 nised that, as they demonstrate the condition of the 
 globe not to have been always what it is now, any true 
 theory of the earth must trace the history of the 
 planet back to a time before the present condition 
 was established. Like Descartes and Leibnitz, he 
 saw that this history must be intimately linked with 
 that of the solar system, of which it formed a part. 
 He thought that the various planets were originally 
 portions of the mass of the sun, from which they 
 were detached by the shock of a comet, whereby the 
 impulse of rotation and of revolution in the same 
 general plane was communicated to them. In com- 
 position, therefore, they are similar to their parent 
 sun, only differing from that body in temperature. 
 He inferred that at first they were intensely hot and 
 self-luminous, but gradually became dark as they 
 cooled, the central sun still remaining in a state of 
 incandescence. 
 
 Though the hypothesis of a cometary shock is not 
 now entertained, it is impossible to refuse our admira- 
 tion to the sagacity of a man who tried to solve the 
 problem of planetary evolution by the application of 
 the laws of mechanics. The geological portion of his 
 theory, however, was loaded with several crude con- 
 
90 Bufforis Epoques de la Nature 
 
 ceptions. The enormous numbers and wide diffusion 
 of fossil shells, which had so vividly impressed his 
 imagination, proved to him that the land must have 
 lain long under the sea. But he had no idea of any 
 general cause that leads to elevation of the sea-bottom 
 into land. He was thus constrained to resort to his 
 imagination for a solution of the problem. Burnet 
 had supposed the original ocean to be contained within 
 the earth, and that it only escaped at the time of 
 the Flood, when, by the heat of the sun, the crust 
 of the globe had cracked, and thus allowed the pent- 
 up waters to rush out. Buffon's theory was hardly 
 less fanciful. But he reversed the order of events. 
 He inferred from the abundance of fossil shells that 
 there had once been a universal ocean, and that by 
 the giving way of the crust, a portion of the waters 
 was engulfed into caverns in the interior, so as to 
 expose what are now mountains and dry land. 
 
 For some thirty years after the publication of his 
 Theory^ Buffon continued to work industriously in all 
 departments of natural history. At last, in 1778, 
 having long meditated on the problem of the origin 
 of the earth, he published his famous Epoques de la 
 Nature. In this work he arranged the history of the 
 globe in six epochs intervals of time of which the 
 limits, though indeterminate, seemed to him none the 
 less real. He tried indeed to form some idea of their 
 duration on the basis of a series of ingenious experi- 
 ments with globes of cast-iron of different sizes, and 
 though the method on which he proceeded could not 
 give him reliable results, and his estimates have ac- 
 cordingly no scientific value, they possess the highest 
 
Buffon on Book of Genesis 91 
 
 historical interest, first as the earliest recorded attempt 
 to compute the probable age of the earth and of the 
 planets from physical observations, and secondly as an 
 epoch-making departure from the old and orthodox 
 notion that our globe came into existence only some 
 six thousand years ago. In discussing the Biblical 
 narrative of the Creation, Buffon boldly asks what we 
 can possibly understand by the six days, if not six 
 periods of time or intervals of duration. Though 
 referred to in the Book of Genesis as days, for want 
 of another term, they can have no relation to our 
 actual days, seeing that no fewer than three of them 
 had passed away before the sun was fixed in the 
 firmament. " The sense of the narrative seems to 
 require that the duration of each ' day ' must have 
 been long, so that we may enlarge it to as great an 
 extent as the truths of physics may demand." 1 
 
 The First Epoch embraced the primeval time when 
 the earth, newly torn from the sun, existed still as 
 a molten mass which, under the influence of rotation, 
 assumed its oblate spheroidal form. The transition 
 from fluidity to solidity, and from luminosity to opacity 
 was brought about entirely by cooling, which com- 
 menced at the outer surface. A crust was thus formed, 
 outside of which the substances still in a vaporous 
 condition, such as air and water, remained as a hot 
 aeriform envelope, while the interior still continued 
 liquid. The period of incandescence before the globe 
 consolidated to the centre was computed by Buffon 
 to have amounted to 2936 years while the period 
 during which the surface remained too hot to be 
 1 Histoire Naturelle, tome in. p. 204. 
 
92 Bufforis Epochs of Earth-history 
 
 touched, and therefore unfit for living beings, com- 
 prised about 35,000 years. 
 
 The Second Epoch was characterized by the con- 
 solidation of the molten globe, and the appearance of 
 hollows and ridges, gaps and swellings, over its surface, 
 and cavernous spaces in its interior, such as may be 
 seen in a globe of fused metal after it has cooled. 
 These inequalities in the crust of granite, gneiss and 
 other ancient crystalline rocks, gave rise to the earliest 
 or primitive mountains and valleys of the higher 
 portions of the land. During the process of con- 
 solidation, cracks arose in which metalliferous veins 
 were formed by sublimation or fusion. Up to the 
 end of this period, the globe remained intensely hot 
 and its water still existed only among the vapours of 
 the atmosphere. 
 
 The Third Epoch, which began about 35,000 years 
 after the birth of the earth, included the time when 
 the waters were condensed so as to descend and 
 remain on the sufficiently cooled surface of the globe. 
 So vast was the sea at first that its surface stood from 
 9000 to 12,000 feet higher than it does now, as was 
 supposed to be indicated by the heights at which 
 marine organisms are found in the rocks of the moun- 
 tains. The waters were at first boiling, and as they 
 cooled, animal life was introduced into them. This 
 life must have been in many ways different from that 
 of our present seas. The oldest species, which are 
 nowhere now to be found alive, flourished during the 
 first ten or fifteen thousand years after the seas had 
 been gathered together. If a collection of fossils were 
 made from the highest parts of the mountains, Buffon 
 
Buff on s Epochs of Earth-history 93 
 
 thought that it might be possible to decide as to the 
 relative antiquity of species. Nature was then, as it 
 seemed to him, in her first vigour, and fashioned larger 
 types of life than now survive. When the earliest 
 condensation of water took place upon the still warm 
 surface of the globe, great corrosion of that surface was 
 effected. The decomposed rocks gave rise to much 
 clay, which was washed off into the sea, there to form 
 the various argillaceous sediments now to be seen on 
 the land. As life increased in the sea, the calcareous 
 fossiliferous formations were deposited which consti- 
 tute so much of the existing land. Buffon supposed 
 that the sea in which all the fossiliferous strata were 
 accumulated must have covered the land for at least 
 20,000 years. The parts of the earth's surface that 
 rise into land were now covered with dense forests. 
 
 The Fourth Epoch witnessed the emergence of the 
 lower part of the land, owing to the sinking of the 
 waters through cracks into cavities in the interior of 
 the globe. Buffon estimated that 20,000 years were 
 required for the lowering of the sea from its original 
 to its present level. Profoundly as he had meditated 
 on the structure of the earth, he had during thirty 
 years made no advance in his views of the origin of 
 the dry land, nor had he obtained any more light on 
 volcanic phenomena than his predecessors had possessed. 
 He estimated that a hundredth or a two-hundredth 
 part of the surface of the earth was covered with 
 dense vegetation, and that vast quantities of this 
 vegetation were swept down into the lower places of 
 the earth's surface and into the fissures of the rocks. 
 He supposed that meeting there with the substances 
 
94 Bufforis Epochs of Earth-history 
 
 sublimed by the great internal heat these carbonaceous 
 accumulations would form the first provision of 
 aliment for the volcanoes which were now to make 
 their appearance. Volcanic energy, in his view, arises 
 from " the effervescence of the pyritous and com- 
 bustible stones/' combined with the effective co- 
 operation of subterranean electricity, which he believed 
 to be likewise a powerful agent in the production of 
 earthquakes. Volcanoes, however, can only become 
 active by " the conflict of a great mass of water with 
 a great body of fire." Hence they are always near 
 the sea. BufFon computed that the first volcanoes did 
 not arise until some 50,000 years of the earth's history 
 had elapsed, by which time a sufficient quantity of 
 combustible materials had been accumulated to furnish 
 them with fuel, and he drew a graphic picture of the 
 frightful condition of our planet when its surface was 
 at once ravaged by fire and devastated by debacles 
 of water. Only after the cessation of such turmoil 
 could terrestrial animals come into being. During this 
 period the retreating waters of the ocean gave birth 
 to powerful currents, whereby hollows were scoured 
 out of the still comparatively soft sedimentary strata, 
 and thus were originated the valleys of the land 
 which have subsequently been widened and deepened 
 by subaerial denudation. 
 
 The Fifth Epoch was marked by a calmer time 
 which witnessed the advent of huge pachyderms 
 elephants, rhinoceroses, and hippopotamuses in the 
 northern regions, where at that time a warm climate 
 stretched continuously from Asia and Europe into 
 America. This introduction of terrestrial animal life 
 
Buff on s Epochs of Earth-history 95 
 
 is placed by Buffon 55,000 or 60,000 years after 
 the beginning of the world, or about 15,000 years 
 before our own time. 
 
 The Sixth Epoch was marked by the separation of 
 the two continents of the Old and New Worlds, 
 which, as was inferred from the presence in each of 
 them of what were supposed to be the same fossil 
 mammals, were believed to have been originally united. 
 Buffon placed this event 10,000 years before his time. 
 The same period also saw the submergence that 
 isolated Greenland from Europe, Canada and New- 
 foundland from Spain, and gave rise to so many 
 insular tracts in the north Atlantic. The history of 
 other late topographical features of the earth's surface, 
 such as the Mediterranean, the Bosphorus, and the 
 Black Sea, is next sketched, and is connected with 
 the occurrence of successive deluges and ruptures of 
 land-barriers. 
 
 Buffon added a seventh epoch, in which he traced 
 the commanding influence of man in modifying the 
 surface of the earth. 
 
 Recognising the powerful agency of rivers and the 
 sea in washing away the materials of the land, he 
 believed that by this action the whole of the existing 
 continents will finally be reduced and covered by the 
 ocean ; and he conceived that by the same series of 
 changes new lands will ultimately be formed. He 
 foresaw, however, the final extinction of our globe as 
 a habitation for sentient beings, but not after the 
 manner of the orthodox creed that the heavens and 
 the earth are at last to melt with fervent heat. Buffon 
 recognised proofs of the gradual refrigeration of our 
 
96 Character of Buff on s Cosmogony 
 
 planet and he estimated that this process would con- 
 tinue for yet 93,000 years by which time the globe 
 would have become colder than ice. Then this 
 beautiful Nature, which with its tribes of plants and 
 animals, will have existed for 132,000 years, will 
 perish. 
 
 In breadth and grandeur of conception BufFon far 
 surpassed the earlier writers who had promulgated 
 theories of the earth. The rare literary skill with 
 which, in his masterpiece, the Epoques, he presented 
 his views, enabled him to exercise a powerful influence 
 on his contemporaries, to direct their attention to the 
 deeply interesting problems of which he wrote, and to 
 give to natural science a far wider popularity than it 
 had before enjoyed. If looking back from our present 
 knowledge, we may be inclined to regard his eloquent 
 pages rather in the light of a pictorial vision of what 
 his brilliant imagination bodied forth as the origin of 
 things, than a sober attempt to work out a theory 
 on a basis of widely collected, carefully sifted and 
 systematically co-ordinated facts, we must remember 
 that science had not yet advanced far enough to pro- 
 vide such a basis. It was his great merit to have 
 pointed out that the history of our earth is a long 
 chronological record, the memorials of which are to 
 be read in the frame-work of the globe itself, and to 
 have himself applied the historical method to its inter- 
 pretation. Nor were his services less conspicuous in 
 breaking down the theological barrier which, after so 
 many centuries, still blocked the way towards a free 
 and unfettered study of the crust of the earth. So 
 powerful in his time did the ecclesiastical authorities 
 
Buffon and the Sorbonne 97 
 
 continue to be, that we are told how, though the 
 Epoques was a work on the preparation of which he 
 had spent much time and thought and which he longed 
 to publish, he had cautiously to feel his way and pay 
 court to some of the doctors of the Sorbonne, and how 
 it was only after having secured, if not the votes, at 
 least the silence of the majority of a corporation which 
 tyrannised over thought, that he ventured to send his 
 treatise to the printer. His friends, however, remained 
 anxious on his account, until whether because religious 
 intolerance was growing less with the advance of 
 science, or because the clerical powers were satisfied 
 with professions of faith and protestations of belief 
 on the part of the author, the work was allowed to 
 pass peaceably on its way to popularity. Although 
 this treatise shows that the long interval of thirty years 
 after the appearance of the Theorie had given greater 
 freedom and had still further enlarged his views of 
 nature, he was evidently unaware of much that had 
 been observed and described during that interval by 
 his own countrymen and in other parts of Europe. 
 In particular he does not seem to have been acquainted 
 with the progress that had been made in evolving a 
 stratigraphical succession among the fossiliferous for- 
 mations in Germany, Italy, and England. One would 
 hardly suppose from his chapters that so much infor- 
 mation had now been amassed regarding fossil organic 
 remains. 
 
 The prolonged controversy over the nature and 
 origin of the " figured stones " had this good result 
 that it not only drew general attention to these objects, 
 but developed a passion for collecting them, and thus 
 
9 8 K. N. Lang and J. J. Scheuchzer 
 
 led to the formation of numerous cabinets or museums 
 wherein they found a conspicuous place among other 
 illustrations of natural history. They were likewise 
 made the subject of description in an increasing num- 
 ber of treatises, and of delineation on engraved plates, 
 although the question was still hotly disputed whether 
 these objects should be considered as mere sports of 
 Nature or as relics of once living things and memorials 
 of the Deluge. Reference was made in the last chapter 
 to one or two of the oldest of these collections of 
 fossils, and to the earlier illustrated works in some of 
 which the fossils were treated as mere " figured stones." 
 After the appearance of the volumes by Lister and 
 others in England, Switzerland became the birthplace 
 of a number of treatises on the subject written, some 
 in Latin and others in German. One of the earliest 
 of these, the Historia Lapidum Figuratorum Helvetia* 
 of K. N. Lang was published in 1708 at Venice, and 
 contained a crude classification of these objects, in 
 which minerals, concretions and fossil remains of 
 animals and plants were all included. This author, 
 though he recognised the resemblance of some of the 
 fossil shells to species now living, believed that their 
 germs were transported as fine dust from the ocean and 
 germinated among the rocks. 
 
 More important were the treatises of J. J. Scheuch- 
 zer (1672-1733) of Zurich. In the year 1702 this 
 writer published a work with the title Specimen Litho- 
 graphic Heheticae curiosc, in which he described 
 <c figured stones " as sports of Nature. But having 
 afterwards procured a copy of Woodward's Essay, 
 which he translated into Latin, he adopted the opinion 
 
Scheiichzers " Fossil Man " 99 
 
 that these stones are relics of the Deluge, and upheld 
 this view in his subsequent writings. He was a most 
 active observer and prolific author. His Natur-Historie 
 des Schweizerlandes is a remarkable dissertation, in which 
 the climate, topography, hydrology (including glaciers), 
 meteorology and mineralogy of the country are well 
 described. There is a section devoted to " Relics of 
 the Deluge found in Switzerland," wherein are de- 
 scribed a number of fossil plants and shells, concluding 
 with a paragraph on " Men." At that time he con- 
 fesses that so rare were human remains in the fossil 
 state that none had yet turned up in his own country, 
 unless he might include the gigantic bones found in 
 Canton Lucerne, though he hopes that some will be 
 found at such time as God may please. This hope he 
 thought was at last realised towards the end of his 
 life by the discovery at Oeningen of a skeleton which 
 he had no doubt was a relic of " one of the infamous 
 men who brought about the calamity of the Flood." 
 He took some pains to let the world know of this 
 important discovery. Thus in a Latin letter to Sir 
 Hans Sloane, to be communicated to the Royal Society 
 of London, into which body Scheuchzer had been 
 elected, he gave a brief description of the specimen, 
 and estimated the stature of the fossil man to have 
 been about the same as his own, or 58 J Paris inches. 
 A fuller account formed the subject of his famous tract, 
 Homo Diluvii Testis (1726). This celebrated specimen, 
 afterwards shown by Cuvier to be not a human skele- 
 ton, but that of a large salamander, is now preserved 
 in the Teyler Museum at Haarlem. 
 
 Scheuchzer wrote a useful catalogue of the names 
 
ioo Scheuchzers Humour 
 
 which up to his time had been given to the ct figured 
 stones " (Sciagraphia Lithologica Curiosa ; sen Lapidum 
 Figuratorum Nomenclator\ and gave references to some 
 of the published descriptions of them. He was like- 
 wise the author of a Herbarium Diluvianum, containing 
 a series of fourteen good plates of fossil plants, 
 together with some corals and other plant-like organ- 
 isms. As a further indication of his connection with 
 England and the Royal Society, it may be mentioned 
 that the first of these plates is inscribed to the Arch- 
 bishop of Canterbury, and the second to Sir Isaac 
 Newton. 
 
 To one further treatise of the Zurich professor 
 reference may here be made for the quaint humour 
 which runs through it. It is a thin small quarto 
 in Latin, with the title Piscium Qiuerel<e et Vindicite^ 
 1708. The fossil fishes are represented as assembled 
 in council to protest against their treatment by the 
 descendants of the wicked men that brought on the 
 Flood by which these very fishes had been entombed. 
 They discourse of " the irrefragable witness of the 
 universal Deluge which by the care of Providence 
 their dumb race places before unbelievers for the 
 conviction of the most daring atheists," Specimens of 
 their fossil brethren are appealed to pike, trout, eel, 
 perch, shark and their well-preserved minute struc- 
 ture of teeth, bones, scales and fins is pointed to as a 
 triumphant demonstration that such perfect anatomical 
 detail could be fabricated by no inorganic process 
 within the rocks, as had been maliciously affirmed. 
 
 It was from Nuremburg that the most important 
 work on fossils was issued during this period. Among 
 
G. W. Knorr and J. E. I. Walch 101 
 
 the natives of that quaint old town, George Wolfgang 
 Knorr (1705-1761), who followed the occupation of 
 an engraver, developed such an enthusiasm for natural 
 history objects that he specially devoted himself to 
 the preparation of finely-engraved plates, for the illus- 
 tration of works on botany and conchology, as well 
 as on art. In the end, he began to collect fossils, and 
 to prepare engravings of them and of other specimens 
 contained in some of the cabinets which were now 
 becoming numerous all over Europe. It was his 
 intention to publish a treatise on the subject fully 
 illustrated by himself. He had completed the first 
 volume, but died before any further portion of the 
 work was ready. It is hardly possible to exaggerate 
 the beauty and fidelity of the representations of the 
 fossils in his plates. No such illustrations had ever 
 before appeared, and they have hardly been surpassed 
 since. By delicate lines on the copper plates the most 
 minute intricacies of structure are reproduced, and by 
 thin washes of colour the tints of the original speci- 
 mens are represented. His renderings of dendritic 
 markings, landscape-marble, fossil plants, Crustacea, 
 crinoids, fishes and other fossils are admirable examples 
 of the union of artistic workmanship with scientific 
 accuracy. Fortunately for Knorr's reputation and the 
 progress of science, another enthusiast was ready to 
 take up the work where the Nuremburg artist had 
 left it. J. E. I. Walch (1725-1778) who held the 
 appointment of Professor of Eloquence and Poetry 
 in the University of Jena, was also a collector and 
 student of minerals, rocks and fossils, and in 1762 
 published an excellent little volume, Das Steinreich y 
 
102 J. B. Beringer 
 
 which gives a rough classification of rocks according 
 to their structure, such as Granular, Lamellar, and 
 Filamentous. He was prevailed upon by Knorr's 
 executors to undertake the continuation and publi- 
 cation of the work of the deceased artist. As a large 
 amount of the materials for the plates had already 
 been arranged by Knorr, the hands of the continu- 
 ator were rather tied in regard to the treatment of 
 the subject. But Walch with remarkable industry and 
 perseverance pursued his task until four folio volumes 
 of text and nearly 300 plates had been completed and 
 published under the title of Lapides Diluvii Vniversalis 
 Testes Sammlung von Merckwurdigkeiten der Natur zum 
 Beweh einer allgemeinen Sundfluth. The fourth and 
 last volume containing Systematic Tables and an 
 Alphabetical Index, affording a guide to the contents 
 of the whole work, was published in 1778. In spite 
 of the diluvial creed of the authors, this fine publi- 
 cation marks a notable advance in the palaeontological 
 department of geology. It presents an instructive 
 and detailed statement of all that was known on the 
 subject at the time, with abundant references to the 
 writings of previous authors. 
 
 The craze for collecting u figured stones " and other 
 mineral curiosities, together with the ignorant credulity 
 of many of the collectors, led to the occasional per- 
 petration of practical jokes. One of the most famous 
 instances of this tendency was that of the tricks played 
 off upon the learned Wiirtzburg Professor, J. B. 
 Beringer, who, having with great enthusiasm and with 
 the help of his students made a collection of fossils 
 from the Triassic strata of his neighbourhood, published 
 
J. B. Beringer 103 
 
 in 1726 an illustrated work upon his discoveries. 
 Among the objects depicted by him were figures of 
 celestial bodies, and other remarkable things which 
 he unsuspectingly regarded as of equal significance. 
 When, however, his youthful companions went so 
 far as to manufacture still more grotesque " figured 
 stones/' and dropped them in the quarries into which 
 they led him that he might himself discover them ; 
 and more especially when, at last, besides Hebrew 
 letters, he found his own name inscribed on the stone, 
 the truth dawned on him that he had been hoaxed. 
 He did his best to buy up the edition of his work 
 in which so many of the tricks had been unsuspect- 
 ingly figured and described. But some copies still 
 survive, and examples of the manufactured fossils 
 are preserved in the museums of Wiirtzburg and 
 Munich. 
 
CHAPTER IV 
 
 THE rise of Geology in France. Palissy. The labours of GuettarcL 
 
 WHILE in England, Switzerland, Italy, and Germany 
 the study of fossils was making progress in spite of 
 the controversies to which the subject gave rise, in 
 France for a time less advance could be perceived. It 
 is true that as far back as 1580 the celebrated ceramic 
 artist Bernard Palissy had published some important 
 observations on the petrifaction of wood, as well as on 
 shells and fishes in the rocks, and had called attention 
 to these objects in proof of the former presence of the 
 sea or of lakes, where such organic remains are now 
 found. But it was not until the early part of the 
 eighteenth century that France produced a man worthy 
 to stand in the front rank of the early founders of 
 geology and of whose career some detailed notice 
 may here be given. While Buffo n was indulging in 
 his brilliant speculations as to the origin and history 
 of the earth there lived in Paris at the same time 
 a student of Nature, belonging to a totally different 
 type, who, shunning any approach to theory, dedicated 
 himself with the enthusiasm of a true naturalist to 
 the patient observation and accumulation of facts 
 regarding the rocks of the earth's crust, and to whom 
 
Jean Etienne Guettard 105 
 
 modern geology owes a deep debt of gratitude, that 
 has never yet been adequately paid. This man, Jean 
 Etienne Guettard (1715-1786), was born in the year 
 1715 at the little town of Etampes, about thirty miles 
 S.W. from Paris. 1 As the grandson of an apothecary 
 there, he was destined to succeed to the business of 
 compounding and selling drugs. Before he left home 
 for his professional education, he had already developed 
 a passion for natural history pursuits. When still a 
 mere child, he used to accompany his grandfather 
 in his walks, and his greatest happiness was found in 
 collecting plants, asking their names and learning to 
 recognize them, and to distinguish their different parts. 
 Every nook and corner around Etampes became 
 familiar to him, and in later years he loved to revisit, 
 with the eye of a trained naturalist, the scenes which 
 had fascinated his boyhood. In his writings he loses 
 no opportunity of citing his native place for some 
 botanical or geological illustration. Thus, at the very 
 beginning of a long and suggestive memoir on the 
 degradation of mountains, to which further reference 
 will be made in the sequel, his thoughts revert to 
 the haunts of his infancy, and the first illustration he 
 cites of the processes of decay which are discussed in 
 that paper is taken from a picturesque rock overlook- 
 ing the valley of the Juine, under the shade of which 
 he used to play with his companions. 2 
 
 1 For the biographical facts here given I am indebted to the Eloge of 
 Guettard by Condorcet (CEuvres, edit. 1847, vol. iii. p. 220) and to 
 the personal references which I have met with in Guettard's writings. 
 
 2 Memoir es sur differ entes parties des Sciences et des Arts, tome iii. 
 p. 210 (1770). 
 
106 Guettard 
 
 Having gained the favourable notice of the famous 
 brothers Jussieu, who gave renown to the botanical 
 department of the Jardin des Plantes, he was allowed 
 by his grandfather to choose a career that would 
 afford scope for his ardour in science. Accordingly 
 he became a doctor in medicine. Eventually he was 
 attached to the suite of the Duke of Orleans, whom 
 he accompanied in his travels, and of whose exten- 
 sive natural history collections he became custodian. 
 On the Duke's death he enjoyed from his son and 
 successor a modest pension and a small lodging in 
 the Palais Royal at Paris. 
 
 It was to botany that his earlier years of unwearied 
 industry were mainly given. In the course of his 
 botanical wanderings over France and other countries, 
 he observed how frequently the distribution of plants 
 is dependent upon the occurrence of certain minerals 
 and rocks. He was led to trace this dependence from 
 one district to another, and thus became more and 
 more interested in what was then termed " mineralogy," 
 until this subject engrossed by far the largest share 
 of his thoughts and labours. 
 
 But Guettard was more than merely a mineralogist. 
 Although the words "geology" and "geologist" did 
 not come into use for half a century later, his writings 
 show him to have been a geologist in the fullest sense 
 of the word. He confined himself, however, to the 
 duty of assiduous observation, and shunned the 
 temptation to speculate. He studied rocks as well 
 as minerals, and traced their distribution over the 
 surface of Europe. He observed the action of the 
 forces by which the surface of the land is modified, 
 
His early training 107 
 
 and he produced some memoirs of the deepest interest 
 in physiography. His training in natural history 
 enabled him to recognize and describe the organisms 
 which he found in the rocks, and he thus became 
 one of the founders of palaeontological geology. He 
 produced about 200 papers on a wide range of subjects 
 in science, and published some half-dozen quarto 
 volumes of his observations, together with many 
 excellent plates. 
 
 It is astonishing that this man, who in his day 
 was one of the most distinguished members of the 
 Academy of Sciences of Paris, and who undoubtedly 
 is entitled to rank among the few great pioneers of 
 modern geology, should have fallen into complete 
 oblivion in English geological literature. I shall have 
 occasion to show that the process of ignoring him 
 began even in his lifetime, and that, though free 
 from the petty vanities of authorship, he was com- 
 pelled in the end to defend his claim to discoveries 
 that he had made. After his death he was the subject 
 of a kindly and appreciative ttoge by his friend 
 Condorcet, the perpetual Secretary of the Academy. 1 
 His work was noticed at length in the great Encyclo- 
 pedic Mhhodique of Diderot and D'Alembert, published 
 thirteen years after he was laid in the grave. 2 Cuvier 
 
 1 (Euvres de Condorcet, vol. iii. p. 220. 
 
 2 Geographie Physique by Desmarest, forming vol. i. of the Encyclo- 
 pedie, and published An III (1794). The article on Guettard (by 
 
 Desmarest) gives a critical review of his work, especially of 
 those parts of it which bear on physical geography. The large 
 number and value of his observations on fossil organisms is admitted. 
 But his method of constructing mineralogical maps is severely 
 
io8 Guettard 
 
 in his eloge of Desmarest gave to Guettard the credit 
 of one of his discoveries. 1 But his work seems to 
 have been in large measure lost sight of until in 
 1 862, 2 and again in i866, 3 the Comte d'Archiac dwelt 
 at some length on his services to the progress of 
 geology. More recently Guettard's labours have been 
 the theme of sympathetic comment from Ch. Sainte- 
 Claire Deville 4 and Aime de Soland. 5 
 
 In the geological literature of the English-speaking 
 countries, however, we shall search in vain for any 
 adequate recognition of the place of this early master 
 of the science. The famous classic, Conybeare and 
 Phillips' Outlines of the Geology of England and Wales^ 
 contains a reference to the French observer as the 
 
 handled, and his claim to the discovery of the extinct volcanoes 
 of Auvergne is contemptuously rejected. The whole tone of the 
 article is somewhat ungenerous. The imperfections of Guettard's 
 work are fully set forth, but little is said of its merits. 
 
 1 Cuvier's E/oges Historiques, vol. ii. p. 354 (1819). 
 
 2 A. d'Archiac, Cours de Paleontologie Stratigraphique, pp. 284-304,. 
 1862. 
 
 3 A. d'Archiac, Geologie et Paleontologie, i re partie, pp. 112-118 
 (1866). The account of Guettard in this work is little more 
 than a condensation of the narrative in the author's previous 
 Cours. Even after these appreciative references Lecoq in his 
 Epoques Geologtques de F Auvergne omits Guettard's name from 
 the list of those he specially cites, and when he has occasion to 
 mention him, does so in a very grudging spirit. See his Intro- 
 duction, p. xiii. and vol. iii. p. 155. 
 
 4 Coup d'ceil historique sur la Geologie, pp. 311-314. (1878). 
 
 5 " Etude sur Guettard," Annales de la Societe Linneenne de Main-et- 
 Lolre, I3 me , 14, et i5 me annees, pp. 32-88 (1871, 1872, 1873). This 
 appreciative essay contains a list of Guettard's publications. 
 
Neglect of his writings 1 09 
 
 first man who constructed geological maps. Scrope 1 
 and Daubeny 2 cite him for his observations in 
 Auvergne. But Lyell in his well-known summary 
 of the progress of geology does not even mention 
 his name. 
 
 It is difficult to account for this neglect. Possibly 
 it may be partly attributable to the cumbrous and 
 diffuse style in which Guettard wrote, 3 and to the 
 enormous bulk of his writings. When a man con- 
 tributes scores of voluminous papers to the transactions 
 of a learned academy ; when he publishes, besides, an 
 armful of bulky and closely printed quartos, and when 
 these literary labours are put before the world in by 
 no means an attractive form, perhaps a large share 
 of the blame may be laid to his own door. Guettard 
 may be said to have buried his reputation under the 
 weight of material which he left to support it. 
 
 I cannot pretend to have read through the whole 
 of these ponderous volumes. The leisure of a hard- 
 worked official does not suffice for such a task. But 
 I have perused those memoirs which seemed to me 
 to give the best idea of Guettard's labours, and of 
 the value of his solid contributions to science. And 
 I shall now proceed to give the results of my reading. 
 No one can glance over the kindly eloge by Condorcet 
 
 1 Geology and Extinct Volcanoes of Central France, p. 30, 2nd 
 edition, 1858, 
 
 2 Description of Active and Extinct Volcanoes, p. 729, 2nd edition 
 (1848). 
 
 3 Of this defect no one was more sensible than the author 
 himself. See his Me'moires sur dlfferentes parties des Sciences et des 
 Arts, tome v. p. 421. 
 
1 1 o Guettard 
 
 without a feeling of respect and sympathy for the 
 man who, under many discouragements, and with 
 but slender means, succeeded in achieving so much 
 in such a wide circle of acquirement. And there is 
 thus no little satisfaction in resuscitating among 
 English and American geologists the memory of a 
 man in whom I trust that they will recognise one 
 of the founders of their science, deserving a place 
 not inferior to that of some whom they have long 
 held in honour. 
 
 And first with regard to Guettard's labours in the 
 domain of geographical geology, or the distribution of 
 rocks and minerals over the surface of the earth. I 
 have referred to the manner in which he was gradually 
 drawn into this subject by his botanical excursions. 
 As the result of his researches, he communicated in 
 1746 to the Academy of Sciences in Paris a memoir 
 on the distribution of minerals and rocks. 1 Having 
 been much impressed by the almost entire absence of 
 certain mineral substances in some places, though they 
 were abundant enough in others, he was led to suspect 
 that these substances are really disposed with much 
 more regularity than had been previously imagined. 
 He surmised that, instead of being dispersed at random, 
 they were grouped in bands which have a character- 
 istic assemblage of minerals and a determinate trend, 
 so that when once the breadth and direction of one 
 of these bands is known, it will be possible, even where 
 the band passes into an unknown country, to tell 
 beforehand what minerals and rocks should be found 
 along its course. 
 
 1 Mem. Ac ad. Roy. France, vol. for 1751. 
 
His Mineralogical Map 1 1 1 
 
 The first sentences of his remarkable Memoire et 
 Carte Mineralogique are well worth quoting. " If 
 nothing," he remarks, " can contribute more towards 
 the formation of a physical and general theory of the 
 earth than the multiplication of observations among 
 the different kinds of rocks and the fossils which they 
 contain, assuredly nothing can make us more sensible 
 of the utility of such a research than to bring together 
 into one view those various observations by the con- 
 struction of mineralogical maps. I have travelled with 
 the view of gaining instruction on the first of these 
 two points, and following the recommendation of the 
 Academy, which wished to have my work expressed 
 on a map, I have prepared such a map, which contains 
 a summary of all my observations." 
 
 The idea of depicting the distribution of the mineral 
 products of a country upon a map was not original 
 with Guettard or the Academy of Sciences. It will be 
 pointed out in a subsequent chapter that, as far back 
 as the later years of the previous century, a scheme 
 of this kind was submitted to the Royal Society of 
 London by Martin Lister. 1 There is no evidence, 
 however, that this scheme was known to Guettard, 
 who, though he obtained a large amount of informa- 
 tion about English mineral products, probably derived 
 it all from French translations of English works. He 
 does not appear to have read English. Guettard in- 
 ferred, from his observations over the centre and north 
 of France, that the several bands of rocks and minerals 
 which he had detected were disposed round Paris as 
 
 1 The early history of geological map-making is briefly outlined in 
 chapter xiv. of the present volume. 
 
1 1 2 Guettard 
 
 a centre. The area in the middle, irregularly oval in 
 shape, comprised the districts of sand and gravel, 
 whence he named it the Sandy band. It was there 
 that the sandstones, millstones, hard building stones, 
 limestones, and gun-flints were met with. The second 
 or Marly band, exactly surrounding the first, consisted 
 of little else than hardened marls, with occasional 
 shells and other fossil bodies. The third band, called 
 the " Schitose " [Schistose] or metalliferous, encircled 
 the second, and was distinguished by including all the 
 mines of the different minerals, as well as the pits and 
 quarries for bitumen, slate, sulphur, marble, granite, 
 fossil wood, coal, etc. 
 
 Having convinced himself that these conclusions 
 could be sustained by an appeal to the distribution of 
 the minerals in the northern half of France, he pro- 
 ceeded to put upon a map the information he had 
 collected. Using chemical and other symbols, he 
 placed a sign at each locality where a particular mine- 
 ral substance was known to exist. Moreover, employ- 
 ing a variety of engraved shading, he showed in a 
 general way the position and limits of the great Paris 
 basin. The marly band surrounding the central tract 
 of sandy Tertiary strata was represented as sweeping 
 inland from the coast between Boulogne and Dieppe, 
 through Picardy and the east of France to the Bour- 
 bonnais, where, turning westward, it reached Poitou, 
 and then struck northward to the coast west of the 
 mouth of the Seine. Though erroneously grouping 
 Secondary sometimes with Palaeozoic, sometimes with 
 Tertiary strata, and not accurately coinciding with the 
 modern divisions of the stratigraphical series, the map 
 
His Mineralogical Map 1 1 3 
 
 nevertheless roughly expresses the broad distribution 
 of the formations. 
 
 Having put his data on the map of France, he came 
 to see that his three bands were abruptly truncated 
 by the English Channel and Strait of Dover. Carry- 
 ing out the principles he had established, he conjectured 
 that these bands would be found to pass under the sea 
 and to re-emerge on the shores of England. To test 
 the truth of this hypothesis, he ransacked the French 
 versions of two once famous English books Joshua 
 Childrey's Britannia Baconica^ and Gerard Boate's 
 Ireland*! Natural! Historic? He found much in these 
 volumes to confirm his surmise. Availing himself of 
 
 *" Britannia Baconica, or the natural rarities of England, Scot- 
 land and Wales, according as they are to be found in every shire, 
 historically related according to the precepts of the Lord Bacon." 
 London, 1660. A French translation was published in 1662 and 
 1667. 
 
 2 " Ireland's Natural! Historic, Being a true and ample description of 
 its situation, greatness, shape and nature ; of its hills, woods, heaths, 
 bogs ; of its fruitful parts and profitable grounds, with the severall 
 ways of manuring and improving the same ; with its heads or pro- 
 montories, harbours, roades, and bayes ; of its springs and fountains, 
 brookes, rivers, loghs ; of its metalls, minerals, freestone, marble, sea- 
 coal, turf and other things that are taken out of the ground. And 
 lastly of the nature and temperature of its air and season, and what 
 diseases it is free from or subject unto ; Conducing to the advance- 
 ment of navigation, husbandry and other profitable arts and 
 professions. Written by Gerard Boate, late Doctor of Physick to the 
 State in Ireland, and now published by Samuel Hartlib, Esq., for the 
 common good of Ireland, and more especially for the benefit of 
 the Adventurers and Planters there." It was published in London 
 in 1652, and was dedicated to Oliver Cromwell. A French version, 
 under the title of Histoire Naturelle cflrelande, was published at Paris 
 in 1666 (Diet. Nat. Biog., sub voc. Boate). 
 
ii4 Guettard 
 
 the information afforded by them, he affixed to the 
 map of England the same system of symbols which 
 he had used on that of France, and roughly indicated 
 the limits of his bands across the south-eastern English 
 counties. This portion of his work, however, being 
 founded on second-hand knowledge, is more vague 
 and inaccurate than that which was based on his per- 
 sonal observations in France. 
 
 As an example of the painstaking earnestness with 
 which Guettard made his geological notes, it may be 
 mentioned that among the symbols he employed on 
 his map there was one for shells or marine fossil 
 bodies, and that this sign is plentifully sprinkled over 
 the map. His reading enabled him also to insert the 
 symbol on many parts of the map of England, all the 
 way from the Wash to Sussex. On the map of 
 France, he was able to introduce an additional sign 
 denoting that the shells were not in mere loose deposits, 
 but formed part of solid stone. In a second map, on 
 a smaller scale, accompanying the same memoir, and 
 embracing the whole of Western Europe from the 
 north of Iceland to the Pyrenees and the Mediter- 
 ranean, Guettard marked by his system of notation the 
 localities where various metals, minerals and rocks were 
 known to exist. In this way he brought into one 
 view a large amount of information regarding the 
 geographical distribution of the substances which he 
 selected for illustration. 
 
 This memoir, with its maps, seems to have gratified 
 the Academy of Sciences, for not merely was it inserted 
 in the volume of Transactions for the year, but in the 
 Journal or annual summary of the more important 
 
His Mineralogical Map 1 1 5 
 
 work of the Academy, it occupies a conspicuous place. 
 The official record announced that a new application 
 of geography had been inaugurated by the author, 
 who, neglecting the political limits traced on maps, 
 sought to group the different regions of the earth 
 according to the nature of the substances that lie 
 beneath the surface. " The work of M. Guettard," 
 it is further remarked, " opens up a new field for 
 geographers and naturalists, and forms, so to speak, 
 a link between two sciences which have hitherto been 
 regarded as entirely independent of each other." 1 
 
 I have dwelt at some length on this early work of 
 Guettard because of its importance in the history of 
 geological cartography. These maps, so far as I 
 know, were the first ever constructed to express the 
 superficial distribution of minerals and rocks. The 
 gifted Frenchman who produced them is thus the 
 father of all the national Geological Surveys which 
 have been instituted by the various civilised nations 
 of the Old and the New Worlds. 
 
 This effort in mineralogical map-making was merely 
 the beginning of Guettard's labours in this depart- 
 ment of investigation. " If you will only let me 
 have a proper map of France," he used to say, " I 
 will undertake to show on it the mineral formations 
 underneath." When Cassini's map appeared, it en- 
 abled him to put his design into execution. After 
 incredible exertions, during which he had the illus- 
 trious chemist Lavoisier 2 as an assistant, he completed 
 
 1 Mem. Acad. Roy. Sciences, 1751 ; Journal, p. 105. 
 
 2 See on the subject of Lavoisier's co-operation, D'Archiac's Paleont- 
 ohgte Stratigraphique, p. 290, and postea, p. 34.3. 
 
1 1 6 Guettard 
 
 the mineralogical survey of no fewer than sixteen 
 sheets of the map. These labours involved journeys 
 so frequent and prolonged that it was estimated that 
 he had travelled over some 1600 leagues of French 
 soil. At last, finding the work beyond his strength, 
 he left it to his successor Monnet, by whom the 
 sixteen maps and a large folio of explanatory text 
 were eventually published. 1 
 
 It must be acknowledged, however, that Guettard 
 does not seem to have had any clear ideas of the 
 sequence of formations and of geological structure ; 
 at least there is no sign of any acquaintance with 
 these in his maps or memoir. His work, therefore, 
 excellent as it was for the time, contained little in 
 common with the admirable detailed geological maps 
 of the present day, which not only depict the geo- 
 graphical distribution of the various rocks, but express 
 also their relations to each other in point of structure 
 and relative age, and their connection with the existing 
 topography of the ground. 
 
 In the course of his journeys, Guettard amassed a 
 far larger amount of detailed information than could 
 be put upon his maps. From time to time he em- 
 bodied it in voluminous essays upon different regions. 
 The longest and most important of these is one in 
 three parts on the mineralogy of the neighbourhood 
 of Paris, in which, besides giving an account of the 
 distribution of the minerals and rocks, he pays special 
 attention to the organic remains of that interesting tract 
 of country, and figures a large number of shells from 
 
 1 Atlas et Description Mineralogiques de la France^ entrepris par ordre du 
 Rot par MM. Guettard et Monnet, 1780. 
 
His Palczontological Labours 117 
 
 what are now known as the Secondary and Tertiary 
 formations. 
 
 His natural history predilections led him to take a 
 keen interest in the fossils which he himself collected, 
 or which were sent up to Paris from the country for 
 his examination. He devoted many long and elaborate 
 memoirs to their description, and figured some hun- 
 dreds of them. I may mention, as of particular 
 interest in palaeontological investigation, that Guettard 
 was the first to recognise trilobites in the Silurian 
 slates of Angers. In some specimens which had been 
 sent up to the Academy from the quarries of that 
 district, he observed numerous impressions of organic 
 remains, which he referred to sea- weeds and Crustacea. 
 The latter he sagaciously compared to modern crabs 
 and prawns. They are well-marked trilobites, and 
 his figures of them are so excellent that the genera, 
 and even in some cases the species, can easily be made 
 out. His representation of the large Illanus of these 
 Lower Silurian slates is specially good. His memoir, 
 read before the Academy in 1757, and published in 
 1762^ is thus a landmark in geological literature, for 
 it appeared eighty years before Murchison's Silurian 
 System made known the sequence and abundant organic 
 remains of the Silurian rocks of Wales. 
 
 Guettard's labours in palaeontology ranged over a 
 wide field. We find him at one time immersed in all 
 
 lu Sur les Ardoisieres d'Angers," Tram. Acad. Roy. Sciences, 1762, 
 p. 52. The Dudley trilobite of the Upper Silurian limestone ot 
 England had been figured and described by Lhuyd in his Lithophylacii 
 Britannici Iconographia (1699), Epist. i. p. 96 and PI. xxii. ; a figure 
 of it was subsequently given in Phil. Trans. 1754, PL x i- Fig. 2. 
 
1 1 8 Guettard 
 
 the details of fossil sponges and corals. At another, 
 he is busy with the mollusca of the Secondary and 
 Tertiary rocks. Fossil fishes, carnivora, pachyderms, 
 cetacea all interest him, and find in him an enthusi- 
 astic and faithful chronicler. His descriptions are 
 not of the minutely systematic and technical order 
 which has prevailed since the time of Linnaeus. Yet 
 some of his generic names have passed into the 
 language of modern palaeontology, and one of the 
 genera of Chalk sponges which he described has been 
 named after him, Guettardia. He had within him the 
 spirit of the true naturalist, more intent on under- 
 standing the nature and affinities of organic forms 
 than on adding new names to the scientific vocabulary. 
 His descriptions and excellent drawings entitle him to 
 rank as the first great leader of the palaeontological 
 school of France. 
 
 As far back as the year 1751, when he was thirty- 
 six years old, he presented to the Academy a memoir 
 on certain little-known fossil bodies, in which he 
 struck, as it were, the keynote of his future life in 
 regard to the organic remains enclosed within the 
 stony records of former ages. Like a man entering 
 a vast charnel-house, he sees on every side proofs of 
 dead organisms. Others had observed these proofs 
 before him, and had recognized their meaning, and 
 he alludes to the labours of his predecessors. He 
 especially singles out Palissy, who, as already remarked, 
 was the first in France, some two hundred years 
 before, to embrace fossil shells in his view of Nature, 
 to maintain that they are the productions of the sea, 
 not of the earth, as had been supposed, and to demon- 
 
His remarkable essay on Fossil Shells 1 1 9 
 
 strate from them that France once lay beneath the 
 sea, which had left behind it such vast quantities of 
 the remains of the creatures that peopled its waters. 
 
 In Normandy, whence many of Guettard's early 
 collections came, and where the people of the country 
 looked upon certain fossil bodies as forms of fruit 
 pears and apples that had fallen from the trees and 
 taken a solid form within the earth he tells how 
 half-witted he seemed to them when he expressed a 
 doubt regarding what they believed to be an obvious 
 truth. He recognised the animal nature of the or- 
 ganisms, and asserted that the so-called peaches, apples 
 and pears all belonged to the class of corals, though 
 many of them are now known to be sponges. 
 
 Of all his numerous and voluminous essays on palae- 
 ontological subjects, perhaps that which most signally 
 displays Guettard's modern and philosophical habit of 
 mind in dealing with fossil organisms is a long paper 
 in three parts, which appeared in 1765 under the title, 
 " On the Accidents that have befallen Fassil Shells 
 compared with those which are found to happen to 
 Shells now living in the Sea." * The controversy 
 about " figured stones " had not yet died out, and 
 there were still not a few observers who continued 
 to believe that the apparent shells found in the rocks 
 of the land never really belonged to living creatures, 
 but were parts of the original structure of the earth. 
 It is difficult, perhaps, to imagine ourselves in the 
 position of naturalists who even as late as the middle 
 of the eighteenth century, could still honestly persuade 
 themselves that the organic remains of fossiliferous 
 1 Trans. A cad. Roy. Sciences (1765), pp. 189, 329, 399. 
 
1 20 Guettard 
 
 formations are entirely deceptive and never formed 
 part of living plants or animals. Yet unless we make 
 the effort to realise the attitude of men's minds in 
 those days, we cannot rightly appreciate the acumen 
 and sagacity of the arguments with which Guettard 
 assailed these opinions. In much detail, and with 
 many admirable illustrations drawn from his personal 
 observations all over France, he demonstrated that 
 fossil shells often have attached to them other shells, 
 and likewise barnacles and serpulae ; that many of 
 them have been bored into by other organisms, and 
 that in innumerable instances they are found in a frag- 
 mentary and worn condition. In all these respects 
 the beds of fossil shells on the land are shown to 
 present the closest possible analogy to the floor of the 
 present sea, so that it becomes impossible to doubt that 
 the accidents which have affected the fossil organisms 
 arose from precisely the same causes as those of exactly 
 the same nature that still befall their successors on the 
 existing ocean bottom. 
 
 Of course nowadays such reasoning appears to us 
 so obvious as to involve no great credit to the writer 
 who elaborated it. But we must remember the state 
 of natural knowledge one hundred and forty years 
 ago. As an example of the method of explaining 
 and illustrating the former condition of the earth's 
 surface by what can be seen to happen now, Guettard's 
 memoir is unquestionably one of the most illustrious 
 in the literature of geology, opening up, as it did, a 
 new field in the investigation of the history of our 
 globe, and unfolding the method by which this field 
 must be cultivated. 
 
His Phy Biographical Geology 121 
 
 On what is now known as Physiographical Geology, 
 or the discussion of the existing topography of the 
 land, this same illustrious Frenchman left the impress 
 of his mind. I will cite only one of his contributions 
 to this subject a memoir c ' On the Degradation of 
 Mountains effected in our Time by heavy Rains, 
 Rivers and the Sea." 1 This work, which occupies 
 about 200 quarto pages, deals with the efficacy of 
 moving water in altering the face of the land. At 
 the very beginning of it, he starts with a reminiscence 
 from the scenes of his infancy, and weaves it into the 
 story he has to tell of the ceaseless degradation of 
 the terrestrial surface. He remembers a picturesque 
 crag of the Fontainebleau sandstone which, perched 
 above the slopes of a little valley, had been worn 
 by the weather into a rudely-formed female figure 
 holding an infant, and had been named by the peasantry 
 the Rock of the Good Virgin. That crag, under 
 which he used to play with his schoolmates, had in 
 the interval of less than half a century gradually 
 crumbled away, and had been washed down to the 
 foot of the declivity. In the same neighbourhood he 
 had noticed at successive visits that prominent rocks 
 had made their appearance which were not previously 
 visible. They seemed, as it were, to start out of 
 the ground, yet he knew that they arose simply from 
 the removal of the material that once covered them. 
 In like manner, ravines of some depth were in the 
 course of a few years cut out of ground where 
 there had before been no trace of them. In these 
 
 1 See vol. iii. of his Memoires sur differentes parties des Sciences et 
 des Arts, pp. 209-4.03. 
 
122 Guettard 
 
 striking examples of the general disintegration, he sees 
 only the continual operation of " gentle rains and 
 heavy downpours." 1 
 
 From illustrations supplied by his own earliest ob- 
 servation, he passes on to others drawn either from 
 his personal researches or his reading, and exemplify- 
 ing the potent influence of heavy rains and flooded 
 streams. Not only are the solid rocks mouldering 
 down and strewing the slopes below with their debris, 
 but the sides of the hills are gashed by torrents, and 
 narrow defiles are cut in them, like the Devil's Gap 
 in Normandy. 2 He combats the notion that land- 
 slips, such as had occurred at Issoire in Auvergne 
 in the year 1733, were caused by internal fires or 
 subterranean winds, and agrees with a previous writer 
 in regarding them as the result of the penetration 
 of water from the surface into the interior of the 
 hill. He thus recognises the efficacy of subterranean 
 as well as superficial water, in changing the face of a 
 country. 
 
 He believes the sea to be the most potent destroyer 
 of the land, and as an instance of its power he was 
 accustomed to regard the chalk cliffs of the north- 
 west of France as the relics of a great chain of hills, 
 of which the greater part had been swept away by 
 the sea. 3 He shows, further, that while the hills are 
 worn down by the waves, by the rains, and by the 
 inundations to which the rains give rise, the materials 
 removed from them are not destroyed, but are de- 
 posited either on the land or along the shores of the 
 
 1 " Des pluies et des averses," Op. cit. p. 210. 
 
 2 P. 214. 8 Pp. 22O, 222. 
 
On the river-basins of France 123 
 
 sea. 1 He further points out that the detritus of sepa- 
 rate river-basins may greatly differ, and that materials 
 may be carried into districts where the rocks are 
 entirely distinct from those in the areas whence the 
 transport has taken place. He refers to the practical 
 value of this observation in questions regarding the 
 source of minerals, ores and useful stones. 2 
 
 He is thus led to give, from his wide knowledge 
 of France, a sketch of the character of the rocks in 
 the different river-basins of the country, and the 
 nature of the materials which the rivers have in each 
 case to transport. He passes in review all the large 
 streams that enter the Atlantic from the Rhine to 
 the shores of Gascony, and considers, likewise, the 
 Rhone with its tributaries on the Mediterranean side 
 of the watershed. 3 He infers that all the debris 
 derived from the waste of the land is not carried to 
 the sea, but that a great deal of it is deposited along 
 the borders of the streams, and that though it may 
 be removed thence, this removal must require many 
 ages to accomplish. He thinks that the levels of 
 the valleys are at present being raised owing to the 
 deposit of detritus in them. 4 The plains watered by 
 the rivers are one vast sheet of gravel, the streams 
 having changed their courses again and again, so as 
 to flow in turn over every part of these alluvial 
 tracts. The thickness of detritus brought down by 
 the rivers gradually increases towards their mouths. 
 Near their sources, on the other hand, any sediment 
 which is deposited is in a manner superficial, and is 
 
 1 P. 222. 2 P. 223. 
 
 3 p. 225-324. 4 P. 326. 
 
1 24 Guettard 
 
 liable to continued removal and transportation farther 
 down. 
 
 The fragmentary material that is accumulated along 
 the margin of the sea is, in Guettard's view, derived 
 either from what is borne down by rivers, or from 
 what is made by the sea itself, the whole being ground 
 into powder by the long-continued beating of the 
 waves. The sea not only acts on its shores, but on 
 submerged rocks, and the detritus thus produced is 
 mingled with the triturated remains of corals, shells, 
 fish-bones and marine plants. 1 
 
 Comparatively little information had been gathered 
 in Guettard's time as to the condition of the sea- 
 bottom. There is thus a peculiar interest in noting 
 the ideas which he expresses on this subject. He 
 thinks that, besides what is laid down upon the 
 shore, another portion of the detritus is borne away 
 seawards, and gradually settles down on the sea-floor. 
 As the nature of the part so transported must depend 
 on that of the material on the shore, he is led to 
 enter upon a minute examination of the mineral 
 constitution of the coast- lines of France, both on 
 the Atlantic and Mediterranean margins of the 
 country. 2 
 
 He recognises that soluble substances may be carried 
 for great distances from the land, and may remain 
 dissolved in the sea-water for a very long time. He 
 even conjectures that it is possibly these substances 
 that impart its salinity to sea-water. 3 
 
 FYom all the soundings available in his day, he 
 concludes that the bottom of the sea is, throughout 
 
 !P. 328. 2 P. 328. 3 P. 3 60. 
 
His conception of the sea-floor 125 
 
 its whole extent, covered mostly with sand, which is 
 probably not derived from the detritus of rivers. 1 He 
 observes, regarding this widely-diffused deposit, that 
 it might be thought to be due to the grinding down 
 of submarine rocks by the sea itself. But he con- 
 tends that " how violent soever may be the movements 
 of the sea, they can have but little effect, save on 
 those rocks which emerge above the level of the 
 water, the greatest storms being little felt except on 
 the surface, and for a short way below it." In this 
 sagacious and generally accurate inference, however, 
 he was long before anticipated by Boyle. 
 
 Considering, further, the problem presented by the 
 general diffusion of sand over the bed of the sea, he 
 thinks that the erosive influence of the ocean cannot 
 be enough to account for this deposit, which is spread 
 over so vast an area. He concludes, therefore, that 
 the sand must date back to the remote ages of the 
 destruction of the mountains. The submarine rocks 
 met with in sounding are, he thinks, unquestionably 
 the remains of mountains formerly destroyed, and the 
 detached boulders similarly discovered are no doubt 
 the result of the destruction of these rocks, though 
 in some cases they may have been derived from 
 neighbouring islands where such exist. 2 
 
 No argument against this view of the high antiquity 
 of the sandy sediment on the sea-floor can, he believes, 
 be drawn from the presence of shells, either singly or in 
 numbers, in this sand. These he regards as obviously 
 the relics of molluscs of the present time, those of 
 former ages having been long ago destroyed. 3 
 *P. 401. 2 Pp. 401, 402. 3 P. 4 02 - 
 
126 Guettard 
 
 He remarks, in conclusion, that " it follows, from 
 all the observations here recited, that the deposits 
 laid down by the sea along its shores are sandy and 
 loamy ; that these deposits do not extend far out 
 to sea ; that, consequently, the elevation of new 
 mountains in the sea by the deposition of sediment is 
 a process very difficult to conceive ; that the transport 
 of the sediment as far as the equator is not less 
 improbable ; and that still more difficult to accept is 
 the suggestion that the sediment from our continent 
 is carried into the seas of the New World. In short, 
 we are still very little advanced towards the theory 
 of the earth as it now exists. All the systems which 
 have been devised in this subject are full of difficulties 
 which appear to me to be insoluble." He proposes, 
 finally, to return, should the occasion present itself, 
 to these questions, which are " all the more interesting 
 the more difficult they are to elucidate." J 
 
 It cannot be claimed that such enlightened views 
 regarding the subaerial degradation of the land were 
 now for the first time proclaimed to the world. 
 Guettard had been to some extent preceded by other 
 writers. Thus the English naturalist Ray, some 
 ninety years before, had pointed out how in course 
 of time the whole dry land might be washed into 
 the sea (ante, p. 74). Generelli, too, in his defence 
 of Lazzaro Moro, twenty years before the appearance 
 of Guettard's volume, had dwelt on the evidence of 
 the constant degradation of the mountains by running 
 water, as an argument for the existence of some other 
 natural cause, whereby, from time to time, land was 
 ipp. 402, 403. 
 
His Volcanic Discovery 127 
 
 upraised to compensate for the universal waste. It 
 must be admitted, however, that no one had elabo- 
 rated the subject so fully until it was taken up by the 
 French observer, and that he was the first to discuss 
 the whole phenomena of denudation, apart altogether 
 from theory, as a great domain for accurate and pro- 
 longed observation. 
 
 I have reserved for mention in the last place the 
 discovery for which chiefly Guettard's name has 
 received such mention as has been accorded to it in 
 English scientific literature. He was the first to 
 ascertain the existence of a group of old volcanoes 
 in the heart of France. This contribution to the 
 geology of the time may seem in itself of compara- 
 tively small moment, but it proved to be another 
 important onward step made by the same indefatigable 
 and clear-sighted naturalist, and laid the foundations 
 of another department of the natural history of the 
 earth. It became also the starting-point of one of 
 the great scientific controversies of the latter half 
 of the eighteenth and the first decades of the 
 nineteenth century. There is thus a peculiar interest 
 in watching how the discovery was made and worked 
 out by the original observer. 
 
 The story goes back to the early months of 1752, 
 for on the loth of May of that year Guettard read 
 to the Academy a " Memoir on Certain Mountains 
 in France which have once been Volcanoes." He 
 tells how he had undertaken further journeys for 
 the purpose of obtaining additional information towards 
 the correction and amplification of his map of France, 
 l Mem. Acad. Roy. Sciences, vol. for 1756, p. 27. 
 
128 Guettard 
 
 showing the distribution of his "bands" with their 
 characteristic minerals. He was accompanied by his 
 former schoolfellow and then his valued friend, Male- 
 sherbes. On reaching Moulins on the Allier, he was 
 struck by the nature of the black stone employed 
 for mile-posts, and felt certain that it must be of 
 volcanic origin. On inquiring whence the material 
 came, and learning that it was from Volvic, " Volvic ! " 
 he exclaimed, " Volcani Vicus ! " and at once deter- 
 mined to make without delay for this probably volcanic 
 centre. 1 His excitement in the chase after an unknown 
 volcano seems to have increased with every step of 
 the journey, as more and more of the dark stone 
 appeared in the buildings by the roadside. At Riom 
 he found the town almost entirely built of the material, 
 which he felt sure he had now run nearly to earth. 
 Learning that the quarries were still some two leagues 
 distant, he pushed on to them, and great was his 
 delight to find all his suspicions amply confirmed. 
 He recognised the rock as a solidified current of lava 
 which had flowed down from the high granitic ridge 
 for some five miles into the plain below, and he found 
 
 1 Twenty-eight years after this discovery Guettard found himself 
 forced to defend his claim to be the discoverer of the old volcanoes 
 of Central France, and to ask his friend Malesherbes for his testi- 
 mony to the justice of that claim. Malesherbes accordingly wrote 
 him a letter giving an account of their journey to Auvergne, which 
 Guettard printed in the preface to his treatise, in two volumes, on 
 the mineralogy of Dauphine. It is curious that, with the statements 
 of the two travellers long before in print, Scrope should have 
 published a totally inaccurate version of the journey in the first 
 edition of his Volcanoes of Central France, and should have repeated 
 it in the second edition. 
 
Among the Auvergne Volcanoes 129 
 
 the actual cone and crater from which the molten 
 flood had issued. 
 
 We can follow the enthusiastic explorer with warm 
 sympathy as he eagerly and joyously sees at each 
 onward step some fresh evidence of the true volcanic 
 nature of the rocks around him. Though he had 
 never beheld a volcano, he was familiar with their 
 outlines, from the available engravings of the time. 
 Ascending a hill beyond the quarries, he perceives its 
 conical form to be that of a typical volcano. 1 As he 
 climbs the rough slopes, he identifies the crumbling 
 debris of black and red pumice, together with the 
 blocks of rugged spongy slags and scoriae, as mani- 
 festly the products of a once active volcanic vent. 
 When he reached the truncated summit of the hill, 
 what must have been his delight to behold below 
 him the smooth-sloped hollow of the crater, not now 
 belching forth hot vapours and ashes, but silent and 
 carpeted with grass ! For centuries the shepherds had 
 pastured their flocks on these slopes, and the quarry- 
 men had been busy cutting and sending off the lava 
 for roads and buildings, but no one had ever suspected 
 that this quiet and lonely spot retained such striking 
 monuments of subterranean commotion. 
 
 Descending to the great lava-stream, Guettard scruti- 
 nized its structure as laid open in the quarries, and at 
 once noticed how different in character it was from any 
 other rock he had ever seen in France. He observed 
 
 1 Desmarest affirms that it was not the Puy de la Nugere, the 
 source of the Volvic lava, which Guettard ascended, but the Puy 
 de la Banniere, and that the former hill was unknown to him. 
 Encyclopedic Methodique, Geographic Physique, vol. i. p. 187. 
 
130 Guettard 
 
 it to be divided into sheets inclined with the general 
 slope of the ground, but separated from each other 
 by layers of clay, earth or sand, as in the case of sedi- 
 mentary formations, yet solid, and breaking easily in 
 any direction, so as to lend itself readily to the arts 
 of the stone-mason. 
 
 Travelling southward along the base of the pic- 
 turesque ridge of the Puys, Guettard and Malesherbes 
 reached Clermont, where they procured the services 
 of an intelligent apothecary, who had some knowledge 
 of the topography of the hills. They climbed the 
 steep slopes of the Puy de Dome a hill made famous 
 by Pascal. Everywhere they noticed volcanic debris 
 partially concealed under vegetation. If the view from 
 the first volcano above Volvic delighted the travellers, 
 we can imagine their amazement and pleasure when 
 the marvellous panorama around the highest craterless 
 summit spread itself like a map around them. As 
 their eyes ranged over that array of old volcanoes, so 
 perfect in form that it is difficult to believe them to 
 have been silent ever since the beginning of human 
 history, they could mark the cones rising one behind 
 the other in long procession on the granite ridge, 
 each bearing its cup-shaped crater atop. 
 
 In descending from the mountain they came upon 
 another crater, probably that of the Petit Puy de 
 Dome, a singularly perfect example of the type, some 
 300 feet deep, and the same in diameter of rim, with 
 such regular and smooth slopes that it has been named 
 by the shepherds the Hen's Nest. Everywhere they 
 encountered quantities of pumice, which so entirely 
 convinced Guettard of the true volcanic nature of the 
 
His Volcanic Memoir 131 
 
 district, that he found it unnecessary for his immediate 
 purpose to examine the rest of the puys. Their Cler- 
 mont guide, though he had previously wandered over 
 the hills, had never suspected their volcanic origin ; 
 but he seems to have learnt his lesson promptly, for 
 he soon afterwards, at Guettard's request, sent some 
 details, and wrote about eruptions and explosions as 
 if he had been long familiar with their effects. 
 
 Not only did Guettard detect some sixteen or seven- 
 teen cones, but he observed that their craters looked 
 in different directions, and he thought that they pro- 
 bably belonged to different periods of eruption. The 
 travellers pushed on to the great volcanic centre of 
 Mont Dore. But Guettard was there less successful. 
 He was unaware of the influence of long-continued 
 denudation in altering the external forms of volcanic 
 hills, and was disposed to regard his ill success as 
 probably due to the mantle of vegetation by which 
 so much of the ground was concealed. 
 
 The journey in Auvergne was too brief and hurried 
 to admit of any single point being fully worked out. 
 But Guettard believed that he had amassed material 
 enough to prove the main question which interested 
 him that there had formerly been a series of active 
 volcanoes in the heart of France. So he prepared 
 an account of his observations, and read it to the 
 Academy of Sciences on loth May, 1752. 
 
 This early memoir on the extinct volcanoes of 
 Europe must not be tried by the standard which has 
 now been attained in the elucidation of volcanic rocks 
 and the phenomena of ancient eruptions. We should 
 be unjust if we judged it by the fuller knowledge 
 
132 Guettard 
 
 obtained of the same region of France by the more 
 detailed examination of other observers even in Guet- 
 tard's lifetime. Desmarest, whose splendid achieve- 
 ments will be referred to in the next chapter, was 
 conspicuously guilty of this injustice. He would never 
 allow Guettard credit for his work in Auvergne, find- 
 ing fault with it because it was imperfect and inaccurate. 
 He wished that, before writing on the subject at all, 
 his predecessor had studied the ground more carefully 
 and in greater detail, and had attended to the different 
 conditions and dates of the eruptions. " Can we 
 regard as a true discovery,'' he asks, " the simple 
 recognition of the products of volcanic action, when 
 the facts are presented with so little order and so 
 much confusion ? Such a discovery implies a reasoned 
 analysis of all the operations of fire, of which the 
 results have been studied, so as to reveal the ancient 
 conditions of all the volcanic regions. Without this 
 it is impossible to dignify the recognition of a few 
 stones with the name of a discovery that will advance 
 the progress of the natural history of the earth." l 
 Could any judgment be more unfair ? As if no 
 discovery is entitled to the name, unless it has 
 been elaborated in the fullest detail and followed to 
 its remotest consequences ! When one of Guettard's 
 countrymen and contemporaries could write thus of 
 his claims to recognition, it is not surprising that for 
 the best part of a century his name should have 
 almost entirely passed out of mind. 
 
 That Guettard preceded every one else in the 
 recognition of the old volcanoes of Auvergne, and 
 1 Geographic Physique, Art. " Guettard." 
 
His mews of Volcanic Action 133 
 
 that he thus became the originator of the Vulcanist 
 party in the famous warfare at the end of last century, 
 in no way diminishes the claim of Desmarest to occupy 
 the foremost place among the Vulcanists, and to be 
 ranked as the real founder of volcanic geology. I shall 
 have occasion to dwell at some length on Desmarest's 
 work, which for accuracy and breadth has never been 
 surpassed. 
 
 Guettard, having never seen a volcano, was guided 
 in his observations and inferences by what he had read 
 of volcanic countries, and what he had learnt about 
 lavas by familiarity with specimens of these rocks 
 brought from Vesuvius and other modern volcanoes. 
 He noted the close resemblance between the rocks 
 of Auvergne and the Italian lavas, not only in appear- 
 ance, density and other characters, but in their position 
 on the ground, the specimens which he had gathered 
 from the bottom, sides and crests of the puys having 
 each their own distinctive peculiarities, as in existing 
 volcanoes. He compared the curved lines on some of 
 the rocks of Mont Dore and the Puy de Dome with 
 the ropy crusts of certain Vesuvian lavas. 
 
 When this distinguished man stepped from the 
 observation of fact into the region of theory, he at 
 once fell into error, but the error was one which, as 
 we have seen, had passed current as obvious truth 
 for more than 2000 years. " For the production of 
 volcanoes/' he remarks, " it is enough that there 
 should be within these mountains substances that can 
 burn, such as petroleum, coal or bitumen, and that 
 from some cause these materials should take fire. 
 Thereupon the mountain will become a furnace, and 
 
1 34 Guettard 
 
 the fire, raging furiously within, will be able to melt 
 and vitrify the most intractable substances/' l He finds 
 evidence in Auvergne of this presumed connection 
 between the combustion of carbonaceous substances 
 and volcanic eruptions, and he cites in illustration the 
 Puy de Crouel and Puy de la Poix, near Clermont, 
 where the black bituminous material can actually be 
 seen at the surface. Summing up his observations he 
 concludes thus : " I do not believe that the reality 
 of our volcanoes will now be called in question, save 
 perhaps from anxiety for the safety of the districts 
 around them. For myself, confident as to the first 
 point, I confess that I share in the anxiety regarding 
 the second. Hot springs have generally been regarded 
 as due to some kind of concealed volcanoes. Those 
 of Mont Dore rise at the very foot of the mountains ; 
 those of Clermont are only some two leagues from 
 the chain of the Puys. It may very well be that their 
 high temperature is kept up by the same internal fires 
 which formerly had a communication with these extinct 
 volcanoes, or might now easily establish one should 
 they increase in activity." 2 
 
 His fears for the safety of the Auvernois were by 
 no means shared by the people themselves, for they 
 refused to believe that the Puys, which they had 
 known from infancy as quiet, well-behaved hills, had 
 ever been anything else, and they looked upon the 
 
 1 Trans. Roy. Acad. Sciences for 1756, p. 52. This adoption of the 
 time-honoured belief is severely criticised by Desmarest, but the same 
 belief was subsequently accepted by Werner, and became a prominent 
 item in the Wernerian creed. 
 
 2 0/. cit. p. 53. 
 
On origin of Basalt 135 
 
 learned doctor's descriptions of the former eruptions 
 as mere speculation of his own manufacture. 
 
 In taking leave of Guettard's scientific labours, I 
 must refer to one further essay of his, on account of 
 its connection with his work among the old volcanoes 
 of Auvergne. Eighteen years after his memoir on 
 these hills had been read to the Academy, he published 
 a paper " On the Basalt of the Ancients and the 
 Moderns." 1 The furious war over the origin of 
 basalt, of which I shall give some account in a later 
 chapter, had not yet definitely begun. Various writers 
 had maintained that this rock is of volcanic origin, and 
 we might have supposed that Guettard's experience in 
 Auvergne would have led him to adopt this correct 
 opinion. So far from doing so, however, he entered 
 into an elaborate discussion to show that basalt could 
 not be a volcanic rock. He admitted that it is found 
 among volcanic masses, but he accounted for its pre- 
 sence there by supposing that in some cases it was 
 already in that position before the eruptions, in others 
 that it had been laid down upon the lavas after they 
 had consolidated. c< If a columnar basalt can be pro- 
 duced by a volcano," he asks, " why do we not find 
 it among the recent eruptions of Vesuvius and other 
 active volcanoes ? " After reviewing all that had then 
 been written on the subject, he concludes that " basalt 
 is a species of verifiable rock, formed by crystallization 
 in an aqueous fluid, and that there is no reason to 
 regard it as due to igneous fusion." 2 
 
 1 Memoir es sur dijferentes parties des Sciences et des Arts, tome ii. 
 p. 226 (1770). 
 2 O/. fit. p. 268. 
 
136 Guettard 
 
 We may gather how little was then known of the 
 characters of modern lavas when Guettard was ignorant 
 of the occurrence of columnar structure among them. 1 
 He was as hopelessly wrong in regard to the origin 
 of basalt, as he was with respect to the nature of 
 volcanic action. How this error originated will 
 appear in an examination of the controversy to 
 which basalt gave rise. But the most interesting 
 feature in the passage just cited from Guettard is 
 not his mistake about basalt, but his clear enuncia- 
 tion of his belief in its deposition from aqueous 
 solution, for he thus forestalled Werner in one of 
 the most keenly disputed parts of his geognosy. 
 
 I know nothing more whimsical in the history of 
 geology than that the same man should be the parent 
 of two diametrically opposite schools. Guettard's 
 observations in Auvergne practically started the Vul- 
 canist camp, and his promulgated tenets regarding 
 basalt became one of the watchwords of the Neptunists. 
 
 The notable Frenchman, of whose work I have 
 now attempted to give an outline, must have been 
 a singular figure as he moved about among his con- 
 temporaries. Endowed with a healthy constitution, he 
 had strengthened it by travel, and by a hard and sober 
 life. At last he became liable to attacks of a heavy 
 lethargic sleep, during one of which his foot was 
 burnt. The long and painful healing of the wound 
 he bore with stoical patience, though often convinced 
 of the uselessness of the remedies applied. " I see 
 
 1 We shall find that this ignorance continued for many years 
 after Guettard's time, and was characteristic of the Wernerian 
 school. 
 
His Character 137 
 
 quite well," he would say, " that they want to ward 
 off the stroke ; but they will not succeed." The 
 idea of the kind of death that would terminate his 
 life never left his mind, but did not in the least affect 
 his cheerfulness. He continued to come assiduously 
 to the meetings of the Academy of Sciences alone 
 and on foot, taking only the precaution to carry in 
 his pocket his full address, that in case of anything 
 happening to him, he might be taken home. By 
 degrees he declined to dine with his friends, and then 
 went seldom to see them, quietly assigning as his 
 excuse the fear of troubling them with the sight of 
 his death. He passed away at last on the yth of 
 January 1786 at the age of seventy-one years. 
 
 The kindly eloge of Condorcet enables us to form 
 some idea of the character and peculiarities of the 
 man. From his childhood onwards he was eminently 
 religious. His nature was thoroughly frank and 
 honest, simple and unambitious. Scrupulously exact 
 in his own dealings with fact, he hated everything 
 savouring in the least of insincerity and subterfuge. 
 His transparent sincerity gained him friends every- 
 where ; yet he was readily irritated, and had a certain 
 brusqueness of manner, which perhaps detracted from 
 the charm of his character and led to his being some- 
 times much misunderstood. One of his acquaintances 
 once thanked him for having given a vote in his 
 favour. " You owe me nothing for that," was 
 Guettard's abrupt reply. " If I had not believed 
 that it was right to give it to you, you should not 
 have had it ; for I don't like you." Condorcet tells 
 how, when they met at the Academy on the occasion 
 
138 Guettard 
 
 of the delivery of the customary ttoges of deceased 
 members, Guettard, who looked on all these things 
 as unveracious statements, would say to the perpetual 
 Secretary, " You are going to tell a lot of lies. When 
 it comes to my turn I want only the truth told about 
 me." Condorcet, in sketching the defects as well as 
 the excellences of his friend's character, remarks that 
 in fulfilling his wishes in the strictest sense, he is 
 rendering to Guettard the homage that he himself 
 would most have desired. So little did he try to 
 seem better than he was, that his defects might be 
 most prominent to those who merely casually met 
 him, while his sterling qualities were known only to his 
 friends. u Those who knew Guettard merely by some 
 brusque answer or other indication of bad temper," 
 his biographer remarks, c< would be surprised to learn 
 that this man, so severe in appearance, so hard to 
 please, forced by the circumstances of his position 
 to live alone, had actually adopted the large family 
 of a woman who had been his servant, brought up 
 the children and watched over the smallest details of 
 their education ; that he could never see any one in 
 distress without not only coming to his help, but 
 even weeping with him. He bore the same sensibility 
 towards animals also, and expressly forbade that any 
 living creature should be killed for him or at his 
 house. He was a man who, losing control of his 
 words when in bad humour, had quarrelled more than 
 once with each of his friends, yet had always ended 
 by loving them and being loved more than ever by 
 them ; who had hurt most of his associates in his 
 disputes with them, but yet had preserved the friend- 
 
His position in History of Science 139 
 
 ship of several of them, and had never diminished 
 in any one of them the esteem which it was impossible 
 to refuse to his character and his virtues." l 
 
 Guettard's position in the history of science is that of 
 an indefatigable and accurate observer who, gifted with 
 a keen eye, well-trained powers of investigation, and 
 much originality of mind, opened up new paths in a 
 number of fields which have since been fruitfully 
 cultivated, but who rigidly abstained from theory or 
 speculation. In geology, he deserves to be specially 
 remembered as the first to construct, however imper- 
 fectly, geological maps, the first to make known the 
 existence of extinct volcanoes in Central France, and 
 one of the first to see the value of organic remains 
 as geological monuments, and to prepare detailed 
 descriptions and figures of them. To him also are 
 due some of the earliest luminous suggestions on the 
 denudation of the land by the atmospheric and marine 
 agents. " By his minute and laborious researches he 
 did more to advance the true theory of the earth 
 (on which, however, he never allowed himself to 
 hazard a single conjecture) than the philosophers who 
 have racked their brains to devise those brilliant hypo- 
 theses, the phantoms of a moment, which the light of 
 truth soon remands into eternal oblivion." 2 
 
 1 Condorcet's Eloge, pp. 238, 240. 2 Condorcet, op. cit. 
 
CHAPTER V 
 
 THE Foundation of Volcanic Geology. Desmarest. 
 
 THE leading position acquired by France in the 
 investigation of the history of the earth, through the 
 labours of such men as Descartes, Buffon and Guettard, 
 was well maintained in the later decades of the 
 eighteenth century. Geology indeed as a distinct 
 science did not yet exist. The study of rocks and 
 their contents was known as mineralogy, which as a 
 pursuit, often of economic value, had been in vogue 
 for centuries. The idea that beyond the mere variety 
 of its mineral contents, the crust of the earth con- 
 tained a record of the earth's evolution, for many 
 ages before the advent of man, only very slowly took 
 definite shape. Buffon partly realized it ; Guettard 
 had a fuller perception of its nature, though he failed 
 to observe proofs of a long succession of changes 
 earlier than the present condition of the surface. 
 
 One of the most valuable parts of Guettard's work 
 was his recognition of the existence of volcanic rocks 
 in regions far removed from any active volcano. We 
 have seen that he was led to this important deduction 
 by a train of observation and inference, and that 
 although he never worked out the subject in detail, 
 
Nicholas Desmarest 141 
 
 the credit of the first discovery, denied to him in his 
 lifetime and after it, must in common fairness be 
 assigned to him. 
 
 Central France was the region that furnished 
 Guettard with his proofs of extinct volcanoes. It was 
 the same region that afterwards supplied fuel to the 
 controversy over the origin of basalt which raged 
 with fury for so many years, and it was from this 
 region also that the proofs were obtained which more 
 than any others brought that controversy to an end. 
 The story of this old battle is full of interest and 
 instruction. We learn from it how the advance of 
 truth may be impeded by personal authority ; how, 
 under guise of the most rigorous induction from fact, 
 the most perverse theories may be supported ; how, 
 under the influence of theoretical preconceptions, the 
 obvious meaning and relations of phenomena may 
 be lost sight of, and how, even in the realm of 
 science, dry questions of interpretation may become 
 the source of cruel misrepresentation and personal 
 animosity. 
 
 To understand the history of this controversy, we 
 must trace the career of another illustrious French- 
 man who, with less opportunity for scientific work 
 than Guettard, less ample qualifications in all depart- 
 ments of natural science, and less promptitude in 
 putting the results of his observations into tangible 
 form, has nevertheless gained for himself an honoured 
 place among the founders of modern geology. 
 
 Nicholas Desmarest (1725-1815) was born in humble 
 circumstances at Soulaines, a little town in France 
 between Bar-sur-Aube and Brienne, on i6th September 
 
142 Desmarest 
 
 1725.* He was thus exactly ten years younger than 
 Guettard. So pinched were the conditions of his 
 youth that he could hardly read even when fifteen 
 years old. From that time, on the death of his 
 father, better prospects dawned upon him. The parish 
 priest urged his guardian to have him educated, as 
 far as the slender means left for his sustenance would 
 allow. He was accordingly sent to the college of 
 the Oratorians of Troyes ; but the pittance available 
 for his benefit was exhausted by the first few terms 
 of his stay there. He had, however, made such 
 marked progress that his teachers, interested in his 
 career, were glad to continue gratuitously the instruc- 
 tion for which he could no longer pay. At the end 
 of his time with them, they passed him on to their 
 brethren in Paris. 
 
 Having made some advance, especially in geometry 
 and physics, he was able to support himself by private 
 teaching and other labours which, however, barely 
 provided the necessaries of life. After some ten years 
 of this drudgery, the studies which had been his 
 occupation and solace, came at last to be the means 
 of opening up a new and noble career to him. 
 
 The appearance of BufFon's Theory of the Earth^ in 
 1749, had had a powerful influence in France in 
 directing attention to the revolutions through which 
 our globe has passed. Among the results of this 
 influence, a society which had been founded at Amiens 
 by the Due de Chaulnes, proposed in 1752 a prize 
 
 1 The biographical details of the following sketch are taken from the 
 well-known eloquent Eloge of Desmarest by Cuvier, Recuei( des Eloges 
 Historiques, edit. 1819, vol. ii. p. 339. 
 
His first geological Essay 143 
 
 for an essay on the question whether England and 
 France had ever been joined together. The subject 
 caught Desmarest's fancy, he made some investiga- 
 tions, sent in an essay and carried off the prize. 
 
 Cuvier, in his E/oge, remarks on the strong con- 
 trast between the way in which Desmarest approached 
 his task and that in which BufFon, who had aroused 
 public attention to these subjects, was accustomed to 
 deal with them. The young aspirant to fame, then 
 twenty-eight years of age, allowed himself no hypo- 
 thesis or theory. He would not travel beyond the 
 positive facts and the inferences that might be 
 legitimately deduced from them. Dealing with the 
 correspondence between the material forming the 
 opposite cliffs of the two countries (which had already 
 been pointed out by Guettard), and with the form 
 of the bottom of the shallow strait, he passed on to 
 consider the former prevalence in England of many 
 noxious wild animals, which could not have swum 
 across the sea, and which man would certainly have 
 taken care not to introduce. From a review of all 
 the considerations which the subject presented, he 
 drew the inference that a neck of land must once 
 have connected England and France, and that this 
 isthmus was eventually cut through by the strong 
 currents of the North Sea. 
 
 This essay, so different in tone from the imaginative 
 discourses of Buffon, attracted the attention of D'Alem- 
 bert, and led him to seek the acquaintance of its 
 author. The friendship of this great man was itself 
 a fortune, for it meant an introduction into the most 
 learned, intelligent, and influential society of the day. 
 
144 Desmarest 
 
 Desmarest was soon actively employed in tasks for 
 which his knowledge and capacity were found to fit 
 him, and thenceforth his struggle with poverty came 
 to an end. Among those who befriended him, the 
 young Due de la Rochefoucault was especially help- 
 ful, taking him on his travels and enabling him to 
 see much of France and Italy. 
 
 Shortly after the middle of the eighteenth century, 
 the Governments of Europe, weaned with ruinous 
 and profitless wars, began to turn their attention 
 towards the improvement of the industries of their 
 peoples. The French Government especially distin- 
 guished itself for the enlightened views which it took 
 in this new line of national activity. It sought to 
 spread throughout the kingdom a knowledge of the 
 best processes of manufacture, and to introduce what- 
 ever was found to be superior in the methods of 
 foreign countries. Desmarest was employed on this 
 mission from 1757 onwards. At one time he would 
 be sent to investigate the cloth-making processes of 
 the country : at another to study the various methods 
 adopted in different districts in the manufacture of 
 cheese. Besides being deputed to examine into the 
 condition of the industries of different provinces of 
 France, he undertook two journeys to Holland to 
 study the paper-making system of that country. He 
 prepared elaborate reports of the results of his investi- 
 gations, which were published in the Memoires of 
 the Academic des Sciences, or in the Encyclopedic 
 Methodique. At last in 1788 he was named by the 
 King Inspector-General and Director of the Manu- 
 factures of France. 
 
Director of Manufactures 145 
 
 He continued to hold this office until the time of 
 the Revolution, when his political friends Trudaine, 
 Malesherbes, La Rochefoucault, and others perished 
 on the scaffold or by the knife of the assassin. He 
 himself was thrown into prison, and only by a 
 miracle escaped the slaughter of the 2nd September. 
 After the troubles were over, he was once more 
 called to assist the Government of the day with his 
 experience and judgment in all matters connected 
 with the industrial development of the country. It 
 may be said of Desmarest that " for three quarters 
 of a century it was under his eyes, and very often 
 under his influence, that French industry attained 
 so great a development." 
 
 Such was his main business in life, and the manner 
 in which he performed it would of itself entitle him 
 to the grateful recollection of his fellow-countrymen. 
 But these occupations did not wholly engross his 
 time or his thoughts. Having early imbibed a taste 
 for scientific investigation, he continued to interest 
 himself in questions that afforded him occupation 
 and solace, even when his fortunes were at the lowest 
 ebb. 
 
 " Resuming the rustic habits of his boyhood," 
 says his biographer, " he made his journeys on foot, 
 with a little cheese as all his sustenance. No path 
 seemed impracticable to him, no rock inaccessible. 
 He never sought the country mansions, he did not 
 even halt at the inns. To pass the night on the 
 hard ground in some herdsman's hut, was to him 
 only an amusement. He would talk with quarry- 
 men and miners, with blacksmiths and masons, more 
 
 K 
 
146 Desmarest 
 
 readily than with men of science. It was thus that 
 he gained that detailed personal acquaintance with 
 the surface of France with which he enriched his 
 writings." 
 
 During these journeyings, he was led into Auvergne 
 in the year 1763, where, eleven years after Guettard's 
 description had been presented to the Academy, he 
 found himself in the same tract of Central France, 
 wandering over the same lava-fields, from Volvic to 
 the heights of Mont Dore. Among the many puzzles 
 reported by the mineralogists of his day, none seems 
 to have excited his interest more than that presented 
 by the black columnar stone which was found in 
 various parts of Europe, and for which Agricola, 
 writing in the middle of the sixteenth century, had 
 revived Pliny's old name of " basalt." The wonder- 
 ful symmetry, combined with the infinite variety of 
 the pillars, the vast size to which they reached, the 
 colossal cliffs along which they were ranged in 
 admirable regularity, had vividly aroused the curiosity 
 of those who concerned themselves with the nature 
 and origin of minerals and rocks. Desmarest had 
 read all that he could find about this mysterious 
 stone. He cast longing eyes towards the foreign 
 countries where it was developed. In particular, he 
 pictured to himself the marvels of the Giant's Cause- 
 way of the north of Ireland, as one of the most 
 remarkable natural monuments of the world, where 
 Nature had traced her operations with a bold hand, 
 but had left the explanation of them still concealed 
 from mortal ken. How fain would he have directed 
 his steps to that distant shore. Little did he dream 
 
Distribution of Basalt in Europe 1 47 
 
 that the solution of the problems presented by basalt 
 was not to be sought in Ireland, but in the heart 
 of his own country, and that it was reserved for 
 him to find. 
 
 Before referring to the steps in Desmarest's progress 
 towards the discovery of the origin of basalt, let me 
 briefly sketch what was known on the subject at 
 the time when he began his researches. Agricola 
 had mentioned that this dark prismatic stone was to 
 be seen in different parts of Germany, and in particular 
 that it formed the eminence on which the old castle 
 of* Stolpen in Saxony had been built. 1 It was after- 
 wards found to be abundantly distributed, not only 
 in Saxony, but in Silesia, in Cassel, and in the 
 valley of the Rhine above Cologne. 2 In these places 
 it is generally to be seen in detached eminences, 
 frequently capping hills, and presenting its vertical 
 columns in rows along its edges. There is nothing 
 about it which in those days was likely to suggest 
 a volcanic origin. The exposures of it in Germany 
 usually belong to an older geological period than the 
 comparatively recent lava-streams of Auvergne, and 
 in the course of time the cones and craters and 
 scoriae, that no doubt originally marked these sites, 
 have gradually disappeared. 
 
 The Giant's Causeway, too, though it displays on 
 a far more colossal scale the characteristic structure 
 and scenery of basalt, is equally silent in regard to 
 
 1 De Natura Fossi/tum, lib. vii. p. 315. Folio, Basel, 1546. 
 
 2 Various authors who had noticed the occurrence of basalt 
 before the publication of his memoir are cited by Desmarest. 
 Mem. Acad. Roy. Sciences, vol. for 1774, p. 726 et seq. 
 
148 Desmarest 
 
 its origin. The marvels of this part of the coast 
 of Ireland had frequently been brought to the notice 
 of the learned, from the latter part of the seventeenth 
 century onward. 1 But here as elsewhere, it was rather 
 the symmetrical structure of the rock than the mode 
 of its formation that engaged the attention of the 
 older observers. Even as far back as the year 1756, 
 one of these writers pointed out the remarkable 
 resemblance of certain rocks in Nassau and in the 
 district of Treves and Cologne to the Giant's 
 Causeway, which by that time had become famous. 2 
 
 The Western Islands of Scotland, which far surpass 
 the Irish coast in the extent and magnificence of their 
 basalt cliffs, were still unknown to the scientific world. 
 The first report about their wonders seems to have 
 reached London in the spring of 1761, when the 
 Bishop of Ossory sent to the Royal Society a letter 
 he had received from E. Mendez da Costa telling 
 him that c< in Cana Island to the southward of 
 Skye and near the island of Rum the rocks rise 
 into polygon pillars . . . jointed exactly like those 
 of the Giant's Causeway." 3 But it was reserved for 
 Sir Joseph Banks to give the first detailed account 
 of the cliffs of Staffa and Fingal's Cave, which from 
 that time shared with the Giant's Causeway in the 
 
 !See Sir R. B., Phil Trans, xvii. (1693) p. 708; S. Foley, 
 xviii. (1694) p. 170, with a map and bird's-eye view. T. Moly- 
 neux, Ibid. p. 181 and xix. (1698) p. 209, with drawings of the 
 columns. R. Pocock, xlv. (1748) p. 124, and xlviii. part i. (1754), 
 with further figures illustrating the jointing of the columns. 
 
 2 A. Trembly, Phil. Tram. xlix. (1756) p. 581. 
 *Phll. Trans, lii. (1761) p. 163, 
 
Theories as to origin of Basalt 1 49 
 
 renown that drew a yearly increasing number of 
 travellers to these distant shores. 1 
 
 Much had thus been learnt as to the diffusion of 
 basalt in Europe, and many excellent drawings had 
 been published of the remarkable prismatic structure 
 of this rock. But no serious attempt seems to have 
 been made to grapple with the problem of its origin. 
 Some absurd notions had indeed been entertained on 
 this subject. The long regular pillars of basalt, it 
 was gravely suggested, were jointed bamboos of a 
 former period, which had somehow been converted 
 into stone. The similarity of the prisms to those of 
 certain minerals led some mineralogists to regard 
 basalt as a kind of schorl, which had taken its 
 geometrical forms in the process of crystallization. 
 Rome de Lisle is even said to have maintained that 
 each basalt prism ought to have a pyramidal termina- 
 tion, like the schorls and other small crystals of the 
 same nature. 2 
 
 Guettard, as we have seen, drew a distinction 
 between basalt and lava, and this opinion was general 
 in his time. The basalts of Central and Western 
 Europe were usually found on hill tops, and dis- 
 played no cones or craters, or other familiar sign 
 of volcanic action. On the contrary, they were not 
 infrequently found to lie upon, and even to alternate 
 
 1 See Pennant's Tour in Scotland, 1772, where Banks' narrative 
 is inserted with a number of excellent engravings of the more 
 remarkable features in Staffa. 
 
 2 In the second edition of his Crystallographie (1783) he clearly 
 distinguishes between crystallization and basaltic structure. The 
 latter he regards as due to desiccation or cooling, tome i. p. 439. 
 
150 Desmarest 
 
 with, undoubted sedimentary strata. They were, 
 therefore, not unnaturally grouped with these strata, 
 and the whole association of rocks was looked upon 
 as having had one common aqueous origin. It was 
 also a prevalent idea that a rock which had been 
 molten must retain obvious traces of that condition 
 in a glassy structure. There was no such con- 
 spicuous vitreous element in basalt, so that this 
 rock, it was assumed, could never have been vol- 
 canic. 1 As Desmarest afterwards contended, those 
 who made such objections could have but little 
 knowledge of volcanic products. 
 
 We may now proceed to trace how the patient 
 and sagacious Inspector of French industries made 
 his memorable contribution to geological theory. It 
 was while traversing a part of Auvergne in the year 
 1763 that he detected for the first time columnar 
 rocks in association with the remains of former 
 volcanoes. On the way from Clermont to the Puy 
 de Dome, climbing the steep slope that leads up to 
 the plateau of Prudelle, with its isolated outlier of a 
 lava-stream that flowed long before the valley below 
 it had been excavated, he came upon some loose 
 columns of a dark compact stone which had fallen 
 from the edge of the overlying sheet of lava. He 
 found similar columns standing vertically all along 
 the mural front of the lava, and observed that they 
 were planted on a bed of scoriae and burnt soil, 
 beneath which lay the old granite that forms the 
 foundation rock of the region. He noticed still 
 
 1 See for instance Wallerius' Mineralogia (1773), i. p. 336, replied 
 to by Desmarest, Mem. Acad. Roy. Sciences (1774), p. 753. 
 
The stages of his research on Basalt 1 5 1 
 
 more perfect prisms a little further on, belonging 
 to the same thin cake of dark stone that covered 
 the plain which leads up to the foot of the great 
 central puy. 
 
 Every year geological pilgrims now make their 
 way to Auvergne, and wander over its marvellous 
 display of cones, craters and lava-rivers. Each one 
 of them climbs to the plateau of Prudelle, and from 
 its level surface gazes in admiration across the vast 
 fertile plain of the Limagne on the one side, and 
 up to the chain of the puys on the other. Yet 
 how few of them connect that scene with one of 
 the great triumphs of their science, or know that 
 it was there that Desmarest began the observations 
 which directly led to the fierce contest over the origin 
 of basalt ! 
 
 That cautious observer tells us that amidst the 
 infinite variety of objects around him, he drew no 
 inference from this first occurrence of columns, but 
 that his attention was aroused. He was kept no 
 long time in suspense on the subject. " On the 
 way back from the Puy de D6me," he tells us, "I 
 followed the thin sheet of black stone and recognised 
 in it the characters of a compact lava. Considering 
 further the thinness of this crust of rock, with its 
 underlying bed of scoriae, and the way in which it 
 extended from the base of hills that were obviously 
 once volcanoes, and spread out over the granite, I 
 saw in it a true lava-stream which had issued from 
 one of the neighbouring volcanoes. With this idea 
 in my mind, I traced out the limits of the lava, 
 and found again everywhere in its thickness the 
 
152 Desmarest 
 
 faces and angles of the columns, and on the top 
 their cross-section, quite distinct from each other. 
 I was thus led to believe that prismatic basalt 
 belonged to the class of volcanic products, and that 
 its constant and regular form was the result of its 
 ancient state of fusion. I only thought then of 
 multiplying my observations, with the view of estab- 
 lishing the true nature of the phenomenon, and its 
 conformity with what is to be found in Antrim 
 a conformity which would involve other points of 
 resemblance." 
 
 He narrates the course of his discoveries as he 
 journeyed into the Mont Dore, detecting in many 
 places fresh confirmation of the conclusion he had 
 formed. But not only did he convince himself 
 that the prismatic basalts of Auvergne were old 
 lava-streams, he carried his induction much further 
 and felt assured that the Irish basalts must also 
 have had a volcanic origin. u I could not doubt," 
 he says, " after these varied and repeated observa- 
 tions, that the groups of prismatic columns in 
 Auvergne belonged to the same conformation as 
 those of Antrim, and that the constant and regular 
 form of the columns must have resulted from the 
 same cause in both regions. What convinced me 
 of the truth of this opinion was the examination of 
 the material constituting the Auvergne columns with 
 that from the Giant's Causeway, which I found to 
 agree in texture, colour and hardness, and further, 
 the sight of two engravings of the Irish locality 
 which at once recalled the scenery of parts of Mont 
 Dore. I draw, from this recognised resemblance 
 
Discovers the volcanic origin of Basalt 153 
 
 and the facts that establish it, a deduction which 
 appears to be justified by the strength of the 
 analogy namely, that in the Giant's Causeway, and 
 in all the prismatic masses which present themselves 
 along the cliffs of the Irish coast, in short even 
 among the truncated summits of the interior, we 
 see the operations of one or more volcanoes which 
 are extinct, like those of Auvergne. Further, I am 
 fully persuaded that in general these groups of 
 polygonal columns are an infallible proof of an old 
 volcano, wherever the stone composing them has a 
 compact texture, spangled with brilliant points, and 
 a black or grey tint." 
 
 Here, then, was a bold advance in theoretical as 
 well as observational geology. Not only was the 
 discovery of Guettard confirmed, that there had 
 once been active volcanoes in the heart of France, 
 but materials were obtained for explaining the origin 
 of certain enigmatical rocks which, though they had 
 been found over a large part of Europe, had hitherto 
 remained a puzzle to mineralogists. This explana- 
 tion, if it were confirmed, would show how widely 
 volcanic action prevailed over countries wherein no 
 sign of an eruption has been witnessed since the 
 earliest ages of human history. 
 
 Desmarest was in no hurry to publish his discovery. 
 Unlike some modern geologists, who rush in hot 
 haste into print, and overload the literature of the 
 science with narratives of rapid and imperfect observa- 
 tions, he kept his material beside him, revolving the 
 subject in his mind, and seeking all the information 
 that he could bring to bear upon it. He tells us that 
 
1 54 Desmarest 
 
 in the year following his journey in Auvergne, he spent 
 the winter in Paris, and while there, laid before the 
 Intendant of Auvergne the desirability of having the 
 volcanic region mapped. His proposition was accepted, 
 and Pasumot, one of the state surveyors, was entrusted 
 with the task of making a topographical map of the 
 region from Volvic to beyond Mont Dore. The 
 whole of the summer of 1764 was taken up with 
 this work. Desmarest accompanied the geographer, 
 who himself had a large acquaintance with the minera- 
 logy of his day. The final result was the production 
 of a map which far surpassed anything of the kind 
 that had before been attempted, in the accuracy, 
 variety, and clearness of its delineations of volcanic 
 phenomena. 
 
 At last, in the summer of 1765, after two years 
 of reflection, Desmarest communicated to the Academy 
 of Sciences at Paris the results at which he had arrived. 
 But even then he showed his earnest desire for the 
 utmost accuracy and fulness attainable. He kept back 
 his paper from publication. Next year he returned 
 to Auvergne, after a prolonged journey through the 
 volcanic regions of Italy, from the Vicentin and Padua 
 southwards to Naples and Vesuvius. In 1769 he 
 once more revisited the volcanoes of Central France, 
 extending his excursions into the Cantal. In the early 
 part of the summer of 1771 he again brought before 
 the Academy the results of his researches on the origin 
 and nature of basalt, embodying in his Memoir the 
 mass of material which his extended travel and mature 
 reflection had enabled him to bring together. But 
 it was not until three years later, viz., in 1774, that 
 
Publishes kis Memoir on Auvergne 155 
 
 his long-delayed essay at last appeared in the annual 
 volume of the Memoirs of the Academy. Life was more 
 placid in those times than it has since become. The 
 feverish haste to be famous, and the frantic struggle 
 for priority, which are now unhappily so rampant, were 
 but little known in Desmarest's days. He kept his 
 work eleven years beside him, enriching it continually 
 with fresh observations drawn from extended journeys, 
 and thus making his conclusions rest on an ever- 
 widening basis of accurately determined fact. 
 
 The Memoir, as finally published, was divided into 
 three parts, two of which appeared together, the third 
 not until three years later. In the first part, the author 
 narrated his observations in Auvergne and other dis- 
 tricts, bearing on the nature of basalt. It would take 
 too much space here to follow him through his survey 
 of the regions where he found the evidence which he 
 brought forward. Let me refer merely to the conclud- 
 ing pages, in which he states his opinion as to the 
 origin of the columnar rock which he had tracked with 
 such diligence from district to district. His account, 
 he remarks, would be incomplete if he did not indicate 
 at the same time the materials which have been melted 
 by the fire in order to produce basalt. He had 
 collected a series of specimens of granite which he 
 believed to represent these materials. They had under- 
 gone different degrees of alteration, some showing still 
 their spar, quartz or other minerals, while others had 
 partly undergone complete fusion. He had convinced 
 himself that various other volcanic rocks besides basalt 
 had resulted from the fusion of granite, the base of 
 which may have been completely melted, while the 
 
156 Desmarest 
 
 quartz of the original rock remained unchanged. He 
 was not aware that the difference of chemical com- 
 position demonstrates that the melting of granite could 
 never have produced basalt. 
 
 These ideas, which we now know to be erroneous, 
 might readily occur to the early observers. It is 
 undoubtedly true that pieces of more or less completely 
 melted granite are to be found among the ejections of 
 old volcanoes, and the inference would not unnaturally 
 suggest itself that if our artificial fires, kindled by the 
 combustion of carbonaceous substances, are sufficient to 
 melt rocks, the far more gigantic conflagrations of 
 such combustible materials, caused by natural processes 
 in the bowels of the earth, when concentrated at one 
 point underneath a volcano, may fuse the surrounding 
 and overlying rocks, and expel streams of molten 
 material. We shall find that Werner adopted this 
 antiquated opinion, and that through him it became 
 predominant over Europe, even after more enlightened 
 conceptions of the subject had been announced. Des- 
 marest does not, indeed, seem to have had at this 
 time, if ever, any very definite conception of the origin 
 of the high temperature within volcanic reservoirs. 
 Nor had chemistry yet afforded much assistance in 
 ascertaining the resemblances and differences among 
 rocks and minerals. His mistakes were thus a faithful 
 reflex of the limited knowledge of the period in which 
 he wrote. 
 
 In the second part of his Memoir, Desmarest gives 
 a historical narrative of all that had been written before 
 his time on the subject of basalt. The most interesting 
 and important passages in this retrospect are the com- 
 
His brilliant generalisation 157 
 
 ments of the author on the writings which he sum- 
 marises, and the additions which he is thereby enabled 
 to make to the observations already given by him. 
 He confesses that, had he begun his investigations 
 among such isolated patches of basalt as those capping 
 the hills in Cassel and Saxony, he would never have 
 been able to affirm that basalt is only a lava. But he 
 had encountered such perfect demonstration of the 
 volcanic nature of the rock, tracing it with its fresh 
 scoriae up to the very craters whence it flowed, that 
 he could not allow this clear evidence to be invalidated, 
 or even weakened, by cases where the volcanic origin 
 had been more or less obscured. 
 
 It is at this point in his investigation that the genius 
 of Desmarest shines with a brilliance far above that of 
 any of his Continental contemporaries who concerned 
 themselves with geological problems. Guettard had 
 clearly indicated the volcanic origin of the puys of 
 Auvergne, and no great acumen was needed to follow 
 up the clue which he had thus given. But to trace a 
 pathway through the maze of lavas of many different 
 ages, to unite and connect them all in one method of 
 interpretation, and thus to remove the endless diffi- 
 culties and harmonise the many apparent contradictions 
 which beset the investigation, was a task which called 
 forth the highest powers of observation and induction. 
 Among the many claims of France to the respect and 
 gratitude of all students of geology, there is assuredly 
 none that ought to be more frankly recognised than 
 that, in her wide and fair domain, she possessed a 
 region where the phenomena were displayed in un- 
 rivalled perfection, and that in Desmarest she could 
 
158 Desmarest 
 
 claim a son gifted with the skill, patience, imagination, 
 and originality that qualified him so admirably for 
 the laborious task which he undertook. His achieve- 
 ments form one of the most notable landmarks in 
 the early history of geology. 
 
 Desmarest, wandering over the volcanic districts of 
 Central France, had been profoundly impressed, as 
 every traveller must be, by the extraordinary varieties 
 in the condition of the various lava-currents. Some 
 of these sheets of rock retain still the dark, verdureless, 
 rugged surfaces which they assumed ages ago when 
 their molten floods stiffened into stone. Others have 
 lost their covering of scoriae, and are seen clinging to 
 the sides of valleys, in positions which seem impossible 
 for any lava-current to have taken. Others are perched 
 in solitary outlying sheets on the tops of plateaux, 
 with no cone near them, nor any obvious source from 
 which they could have flowed. 
 
 Pondering on these apparently contradictory pheno- 
 mena, Desmarest, with the inspiration of true genius, 
 seized on the fruitful principle that would alone 
 explain them. He saw that the varying conditions 
 of the several lavas were due to the ceaseless influence 
 of atmospheric denudation. He convinced himself 
 that the detached outliers of basalt, capping the ridges 
 and plateaux are really remnants of once continuous 
 sheets of lava, and that their isolation, together with 
 the removal of their original covering of scoriae and 
 slags, is to be ascribed to the operations of rain and 
 melted snow. The depth of the valleys cut through 
 these lava-platforms was found by him to be com- 
 mensurate with the antiquity of the lavas, and with 
 
His interpretation of the Origin of Valleys 1 59 
 
 the size of the streams that flowed between the severed 
 escarpments. 
 
 He ascertained that, in proportion to their antiquity, 
 the lava-streams had lost, one after another, the usual 
 outward features of the younger sheets. The super- 
 ficial scoriae had disappeared, and the craters were 
 worn away, until only scattered outliers of compact 
 dark rock remained. Yet between this extreme and 
 that of the most recent eruptions, where the lavas, in 
 unbroken, rugged, cavernous sheets, extend from their 
 craters down into the present valleys, where they 
 have driven aside the running streams, every inter- 
 mediate stage could be found. 
 
 Thus the doctrine of the origin of valleys by the 
 erosive action of the streams which flow in them, 
 though it has been credited to various writers, 1 was 
 first clearly taught from actual concrete examples by 
 
 1 Thus by Lyell and Murchison it was ascribed to H. B. de 
 Saussure, Playfair, and Montlosier, Edin. New Phil. Journ. vol. vii. 
 (1829), p. 15. In England it has been more commonly assigned to 
 Hutton and Playfair, and to Scrope. The ascription of the doctrine 
 to Montlosier was singularly unfortunate. That writer states that it 
 had been the labour of his life (he was 34 years of age at the time 
 he wrote) to study the valley system of Auvergne, and that he was 
 on the point of publishing his opinion that the valleys have been 
 carved out by the streams which still flow in them, when he dis- 
 covered that De Saussure had already published the same conclusion. 
 De Saussure's second volume from which Montlosier quotes was 
 published in 1786. But Desmarest's memoir, in which the subaerial 
 origin of the Auvergne valleys was proclaimed, had appeared some 
 twelve years earlier. Montlosier was acquainted with that Memoir, 
 for he cites it more than once. The doctrine of the carving out of 
 valleys by atmospheric denudation became a prominent part of Hut- 
 ton's theory of the earth. See also ante, p. 121, for Guettard's views. 
 
1 60 Desmarest 
 
 Desmarest. The first attempt to trace back the history 
 of a landscape, to show its successive phases, and to 
 connect them all with the continuous operation of the 
 same causes which are still producing like effects, was 
 made by this illustrious native of France. 
 
 So satisfied was Desmarest with the proofs furnished 
 by Auvergne regarding the volcanic origin of basalt, 
 that he coined the term " basalt-lava/' with an apology 
 to the mineralogists, and remarked that when once 
 the characters of this rock have been appreciated, it 
 may be recognised everywhere, in spite of the most 
 stupendous degradation. Casting his eye over the 
 map of Europe, and noting the localities from which 
 the occurrence of basalt had been reported, he saw 
 tv/o great regions of ancient volcanic activity in the 
 heart of the continent. One of these lay to the east, 
 along the confines of Saxony and Bohemia into Silesia, 
 from Freiberg to Lignitz ; the other stretched from 
 the Rhine above Cologne, through Nassau, Hesse- 
 Darmstadt, and Cassel. 
 
 The map which has been already referred to as 
 accompanying this remarkable memoir, depicts with 
 great clearness the grouping of the volcanoes over a 
 large part of Auvergne. It represents them by distinct 
 kinds of engraving, so as to show four classes differing 
 from each other in age and other characters. The 
 first of these classes includes the younger lava-streams, 
 not yet cut through by running water, and still con- 
 nected with their parent cones. The second embraces 
 those lavas which bear decomposed earthy materials 
 on their surface, and from which their original craters 
 have disappeared. In the third class are ranged those 
 
Slow elaboration of his Memoirs 1 6 1 
 
 lavas which have been reduced to detached outliers 
 separated by valleys ; while in the fourth, some isolated 
 masses are placed which Desmarest thought had been 
 " melted in place," or erupted where they now appear. 
 
 The third part of the memoir, though read with the 
 second part in 1771, was not published until 1777. In 
 this essay the author discussed the basalt of the ancients, 
 and the natural history of the various kinds of stones 
 to which at different times the term basalt had been 
 applied. 
 
 It is interesting to follow the slow elaboration of his 
 views through his successive memoirs. We must 
 remember that, during those busy years, his time and 
 thoughts were chiefly taken up with the inquiries 
 into industrial development which the Government 
 of the day had entrusted to him, and which necessitated 
 frequent and prolonged journeys, not only in France, 
 but in other countries of Europe. Being convinced 
 that the great questions in physical geography which 
 specially occupied his attention could best be studied in 
 Auvergne, he returned to that region at every avail- 
 able opportunity, revisiting again and again localities 
 already familiar to him, and testing his deductions 
 by fresh appeals to nature. Four years after his great 
 monograph on the origin of basalt had been read to 
 the Academy of Sciences, he presented another essay, 
 developing still further the ideas of denudation and 
 successive eruptive periods which had been briefly 
 sketched in his first communication. The scope of 
 this new effort may be judged of from its full title : 
 " On the Determination of Three Epochs of Nature 
 from the Products of Volcanoes, and on the Use that 
 
1 62 Desmarest 
 
 may be made of these Epochs in the Study of Vol- 
 canoes." This essay was laid before the Academy 
 in the year 1775. An extract from it appeared after 
 the lapse of four years, 1 but the full paper was not 
 published until the year i8o6 2 no less than thirty-one 
 years after its original preparation. During this long 
 interval the controversy about the origin of basalt 
 had extended over most of the countries of Europe, 
 and had involved the very subjects of which Desmarest 
 treated. He himself, keenly as the matters in dispute 
 interested him, took no part in the warfare. In his 
 memoir he ignores the combatants and their strife, 
 but quietly repeats and strengthens statements which 
 he had published a generation before, and which, had 
 they been properly considered and verified, would have 
 prevented any controversy from ever arising. This 
 dispute will further occupy our attention in later 
 pages of this volume. In the meantime let us consider 
 the character of Desmarest's long-delayed contribution 
 to the literature and theory of geology. 
 
 The progress of his investigations had led him to 
 perceive the necessity of correlating the various pheno- 
 mena connected with ancient volcanoes, and especially 
 with reference to the questions of their relative age and 
 of the alterations they have undergone from exposure 
 to the elements. The facts known to him suggested 
 an arrangement of them into three groups or epochs, 
 which were not meant to imply definite periods of 
 time or precise dates, but would express the idea of 
 
 1 Journal de Physique, tome xiii. (i 779), p. 115. 
 
 2 Mem. de FInstit. des Science* Math. etPhys. tome vi. (1806), p. 219. 
 It was read again on ist Prairial, An XII (zoth May, 1804). 
 
His Volcanic Periods 163 
 
 a recognisable succession of events. His researches 
 had assured him that the volcanic history of Auvergne 
 " formed a whole, which, though incomplete, showed 
 that Nature had followed the same order of procedure 
 in the most remote ages as in the most recent times." 
 
 In co-ordinating the appearances presented by the 
 different volcanic masses, he began with the considera- 
 tion of what were obviously the youngest, on the 
 principle that the last operations of Nature are simpler, 
 and have undergone less modification from the in- 
 fluences which are continually changing the face of 
 the land. He perceived that volcanoes are only tem- 
 porary accidents in the midst of the ordinary and 
 normal operations of nature, that the materials erupted 
 by volcanoes, at various intervals from a remote 
 antiquity, must have suffered from the universal 
 degradation, and that the extent of their waste would 
 be proportionate to the length of time during which 
 the loss had been continued. The latest lavas must 
 unquestionably present most nearly the primitive forms 
 of volcanic masses, and should thus serve as a standard 
 for comparison, to be kept before the eyes of every 
 observer who would judge correctly of the extent and 
 progress of the alteration that is to be seen in other 
 regions. 
 
 The first of his three periods includes the products 
 of still active and recently extinct volcanoes. These 
 are distinguished by the association of crater-bearing 
 cones of cinders and scoriae, with streams of rugged 
 lava, which can be followed from the cones into the 
 surrounding country over which they have flowed. 
 The most modern lava-streams are not cut through 
 
1 64 Desmarest 
 
 by valleys, but form continuous sheets. Yet within 
 the limits of this first epoch proofs of alteration mani- 
 fest themselves. The loose scoriae and cinders are 
 washed down to lower levels, the cones are attacked 
 and the lavas begin to be trenched. As these changes 
 advance, the flow of running water gradually cuts 
 through the sheets of lava, and forms valleys across 
 them. The epoch embraced all the ages required 
 for this erosion, and during its continuance repeated 
 outflows of lava took place. Each of these currents 
 of melted rock would seek the lowest levels, and would 
 thus mark the valley-bottom of its time, in the long 
 process of excavation. 
 
 In the records of the second epoch, the scoriae and 
 ashes have been swept away, the cones have entirely 
 disappeared, and the streams of lava have been cut 
 into separate patches by the erosion of the valleys, 
 above which they are now left perched as high plains 
 or plateaux. Notwithstanding the stupendous results 
 thus achieved, Desmarest seeks no vast terrestrial dis- 
 turbance to account for them. He finds their explana- 
 tion in the working of the very same meteoric agents 
 which are still carrying on the same process of degrada- 
 tion. The cellular parts of the lavas, under the 
 influence of the weather, crumble down into mere 
 loose earth, which is easily washed away by rain and 
 melted snow, leaving only the harder and more 
 resisting core of more solid rock. In like manner, 
 the loose materials of the cones are removed, until 
 perhaps only masses of lava remain behind that may 
 have solidified at their bottoms. By this series of 
 operations an entire transformation is wrought on the 
 
His Volcanic Periods 165 
 
 face of the country. Lavas which originally covered 
 the floors of valleys, as the ground around them is 
 lowered, are at last turned into high tablelands, and 
 are still further cut through and separated into 
 detached portions, according to the multiplication and 
 deepening of the ravines and valleys by which they 
 are traversed. To realise the ancient continuity of 
 these venerable lava-sheets, we must in imagination 
 fill up the valleys, and thus restore the slope or plain 
 over which the molten rock originally flowed. 
 
 As all the scoriae and craters are gone, the only way 
 of detecting an eruptive centre in the volcanic products 
 of this epoch is to find the point of common origin 
 for several streams, such points being often marked 
 by large isolated patches of lava (culots). 
 
 Desmarest arrives at the important conclusion that 
 the lavas of his second epoch were erupted before the 
 excavation of the present valleys out of the original 
 plain over which the streams of basalt were poured. 
 The volcanic events of which they are the memorials 
 must thus go back to a remote antiquity, for the 
 erosion of valleys is obviously an exceedingly slow 
 process. But these lavas are evidently much younger 
 than the horizontal sedimentary strata and the granite 
 which these strata overlie, both of these groups of 
 rock being also trenched by the valleys. 
 
 The third and most ancient epoch is denoted by a 
 series of lavas, which, instead of overlying the sedi- 
 mentary strata, underlie them or are interstratified 
 with them. These sediments are now recognized as 
 the deposits of one of the old Tertiary lakes of Europe. 
 Their layers are full of land-plants, land and fresh- 
 
1 66 Desmarest 
 
 water shells, and remains of terrestrial mammals. But 
 to Desmarest they were proofs of the former presence 
 of the sea over the heart of France. He inferred that 
 the pebbles of various lavas which he found among 
 these strata denoted former volcanic eruptions, before 
 the accumulation of the marine deposits. But he 
 noticed also indications of the discharge of lava 
 during the sojourn of the sea over this region. He 
 believed that his third epoch must have lasted some 
 considerable time, so as to permit the deposition of 
 600 or 900 feet of horizontal sediments above the 
 lowest lavas. 1 
 
 He remarks that from ignorance of this method of 
 following the sequence of eruptions and the effects 
 of continuous waste, naturalists had failed to detect 
 the existence of lavas of the second and third epochs 
 in districts where eruptions of the first epoch were 
 no longer to be recognized. These observers, he 
 contended, had misread the evidence of nature, 
 referring what were undoubtedly volcanic rocks to 
 deposition from water, to schists, and to pierre de 
 come, and on the other hand mistaking for volcanic 
 craters what were only hollows dug out by running 
 water in the lavas of the second, or even of the first 
 epoch. 
 
 1 In the article "Auvergne" in his Geographic Physique^ p. 882 
 (published in 1803), he briefly summarises his three epochs thus " I 
 have distinguished three kinds of volcanoes in Auvergne, first, ancient 
 volcanoes ; second, modern volcanoes ; and third, submarine vol- 
 canoes." Probably most of the lavas of his third epoch are rather 
 of the nature of intrusive sills. The subject of ancient volcanic 
 rocks interstratified among sedimentary deposits is discussed in 
 chapter viii. 
 
His cautions generalisations 167 
 
 The sagacity of these generalisations has been amply 
 sustained by the reseaiches of later times. Alike in 
 volcanic geology and in the doctrines of denuda- 
 tion, the labours of Desmarest marked the rise of a 
 new era in the investigation of the past history of 
 the earth. They showed how patient detailed research 
 could solve some of the most transcendently interesting 
 problems in geology, and how the minute and philo- 
 sophical investigation of one small area of the globe 
 could furnish principles of universal application. 
 
 In one respect, perhaps, this far-seeing observer 
 seems to have been almost afraid to push his views of 
 denudation to their logical conclusion. There occur 
 in Central France many flat, isolated areas of basalt, 
 capping detached hills and fragments of plateaux, 
 not apparently connected with any visible lava-current 
 or centre of eruption. The origin of these patches 
 (called by him " culots "), was explained by supposing 
 them to mark the positions of volcanic vents up 
 which the melted material had risen without flowing 
 out, and where it had solidified within the crater, 
 being retained by the encircling wall of scoriae and 
 cinders. The removal of the surrounding loose 
 material would, he thought, leave the lava as a cake 
 with steep scarped sides crowning the slopes below. 
 Possibly some of his culots originated in the way 
 supposed, but there can be little doubt that most of 
 them are remnants of lava-streams reduced to almost 
 the last stage by the progress of denudation. 
 
 From the long intervals which he allowed to elapse 
 between the presentation of his papers to the Academy 
 and their final publication, it might be supposed that 
 
1 68 Desmarest 
 
 Desmarest was probably of a procrastinating, possibly 
 even of an indolent, temperament. Yet, when we 
 consider the amount of work, official and scientific, 
 which he accomplished, we must acquit him of such 
 an imputation. His voluminous reports on the various 
 industries of France show how actively and zealously 
 he laboured in his official harness. But perhaps the 
 best proof of his indefatigable industry was his colossal 
 Gtographu Physique, which he undertook as part of the 
 famous Encyclopedic Methodique founded by Diderot and 
 D'Alembert. The exhaustive treatment of his subject 
 may be inferred from the fact that after devoting to 
 it four massive quarto volumes of from 700 to 900 
 pages each, he had only got to the letter N when 
 death closed his labours. 
 
 The first volume of this great work is in many 
 respects the most interesting. The author in his 
 preface tells how he means to exclude from his task 
 all discussion of theories of the earth, for, as he 
 frankly confesses, he had long looked upon these 
 theories as utterly opposed to the principles of Physical 
 Geography. But on second thoughts, as unfortunately 
 such theories really existed, having much the same 
 relation to Physical Geography that fable bears to 
 history, he had resolved to give a summary of the 
 subject, thus conforming to the practice of some 
 writers who begin their histories with a brief mention 
 of the heroic times. 1 Accordingly he devotes the 
 first volume to notices of the more important authors 
 who had treated of his subject, excluding those who 
 were still alive. He made, however, exceptions to 
 1 Geographie Physique, vol. i. (1794), preface. 
 
His Physical Geography 169 
 
 this exclusion in favour of Pallas and Hutton. 
 Though he undertook to present merely an impartial 
 summary of the opinions of other writers, it is 
 instructive to have these summaries from the hand 
 of a man like Desmarest, who was contemporary with 
 many of those of whom he discourses. The inter- 
 spersed comment and criticism in his notices are 
 specially valuable. 
 
 The other three volumes were devoted to descrip- 
 tions of places, districts, and countries, and to articles 
 or subjects in Physical Geography a branch of know- 
 ledge which Desmarest regarded as embracing two 
 equally important and closely related subjects the 
 interior structure of the globe and its external form. 
 Geology was not yet admitted to a formal place among 
 the sciences, but geological questions occupy a promi- 
 nent place in the massive quartos of the Encyclopedic 
 Mtthodique. 1 
 
 The delays that attended the publication of Des- 
 marest's important and original observations and de- 
 ductions respecting the volcanic geology of Auvergne 
 reached their climax in the case of his detailed map of 
 that region. We have seen that at his instigation a 
 topographical survey of Auvergne on a large scale was 
 begun as far back as 1764, and that reductions of 
 this map accompanied his Memoirs presented to the 
 
 1 Vol. i. of the Geographic Physique appeared in An III (1794); 
 vol. ii. in 1803 ; vol. iii. in 1809, and vol. iv. in 1811. Among 
 the geological articles of interest in these volumes reference may 
 be made to those on Antrim, Auvergne, Basalte, Chaussee des 
 Geans, and Courans. Vol. v., left unfinished by Desmarest, was 
 continued by Bory de St. Vincent, Doin, Ferry, and Huot, and 
 was not published until 1828. 
 
170 Desmarest 
 
 Academy of Sciences. The map itself, however, with 
 all its elaborate detail, bearing on the history of the 
 volcanoes of Central France, still remained in his 
 hands. Year after year he sought to bring it nearer 
 to his ideal of perfection. Every part of the region 
 had been scrupulously examined by him, every puy 
 was set down, every crater was carefully drawn, every 
 current of lava was traced out from its source to its 
 termination, every detached area of basalt was faith- 
 fully represented. By a system of hachures and signs 
 the modern and ancient lavas were discriminated. But 
 he still kept the work back, and when he died it 
 remained unpublished. 
 
 Of all his contributions to the progress of geology, 
 this map must be considered the most memorable. 
 It was the compendium of all his toil in Auvergne, 
 and showed, as in a model, the structure of the country 
 which he had so patiently and successfully elucidated. 
 The reduced map published in his first Memoir and 
 the portions of the map issued with his second Memoir, 
 were all that he allowed to appear in his lifetime, 
 but they failed to impress the minds of his con- 
 temporaries, as the entire map would have done, with 
 its complete and clear delineation of the whole district. 
 Labouring after a perfection which he could not attain, 
 he not only lost the credit which the map would 
 have brought him in his lifetime, but he retarded 
 the progress of the sound views which he himself 
 held and wished to see prevail. Had this truly admir- 
 able map been published by him, together with a 
 general description of the volcanoes depicted on it, his 
 name would have been placed at once and by universal 
 
His Character 171 
 
 assent at the head of the geologists of his day, 
 and the miserable controversy about the nature of 
 basalt would either never have arisen, or could have 
 been speedily set at rest. Cuvier tells us that 
 Desmarest himself was fully conscious of the desira- 
 bility of publishing the map, but his life slipped away 
 as he still aimed at further improvement of it. Yet 
 he could not bear that other observers should enter 
 his volcanic region and describe its features. It used 
 to be said that he seemed to look on Auvergne as his 
 own property, and certainly he was the legitimate owner 
 of many of the observations made there after -him. 
 
 Cuvier, who knew him well and who had watched 
 with interest his declining years, gives us a vivid pic- 
 ture of Desmarest. The illustrious geologist was little 
 fitted to push his way in a society where the most 
 successful art was that of self-advertisement. He took 
 no more pains about his private interest than he did 
 about his rights in regard to scientific discovery, im- 
 portuning neither the dispensers of fortune nor those 
 of fame. With his crust and his cheese, he said, he 
 needed no Government help to visit the manufac- 
 tories or the mountains. In short, in studying all 
 the processes of art, all the forces of nature, he had 
 entirely neglected those arts that sway the world, 
 because nothing which agitates the world could move 
 him. Even works of wit and imagination remained 
 unknown to him, because they did not lie within the 
 range of his studies. His friends used jocularly to 
 affirm that he would have broken the most beautiful 
 statue in order to ascertain the nature of an antique 
 stone, and this character was so widely given to him 
 
172 Desmarest 
 
 that at Rome the keepers of the museums felt some 
 alarm in admitting him. In society, too, things, what- 
 ever they might be, affected him on one side only. 
 For instance, when an Englishman was recounting 
 at the house of the Duchesse d'Anville the then recent 
 thrilling incident in Cook's first voyage, when his 
 vessel, pierced by a point of rock, was only saved 
 from sinking by the stone breaking off and remaining 
 fixed in the hole, every one present expressed in his 
 own way the interest he felt in the story. Desmarest, 
 however, quietly inquired whether the rock was basaltic 
 or calcareous. 
 
 A character so little affected by external things 
 was naturally immovable in regard to relations and 
 habits. From the earliest days when he began to 
 be known, he had been engaged to pass his Sundays 
 at Auteuil with a friend. Ever afterwards he would 
 appear there on the usual day, even when his friend 
 was dead, and when age no longer allowed him to 
 enjoy the country ; and as he had from the first 
 gone on foot, he always went there on foot until he 
 was eighty-five years old. All that his family could 
 then prevail upon him to do was to take a carriage. 
 
 Nor was he less constant in more trivial affairs. 
 Never did he dine or go to bed later one day than 
 another. Nobody remembered ever to have seen him 
 change the cut of his clothes, and down to his last 
 days his wig and his coat recalled the fashions in 
 vogue under the Cardinal de Fleury. 
 
 After recalling his kindliness and helpfulness to 
 poor inventors, for whom he ever evinced the heartiest 
 sympathy, his biographer concludes in eloquent words, 
 
The Close of his Career 173 
 
 with which I may fitly close this sketch of Desmarest's 
 career. " The Academy of Sciences saw in him, as 
 it were, the monument of a bygone age, one of those 
 old philosophers, now too few, who occupied only 
 with science, did not waste themselves in the ambitions 
 of the world, nor in rambling through too wide a 
 range of study, men more envied than imitated, who 
 have supplied us with that succession of octogenarians 
 and nonagenarians, of which our history is full. 
 Living like these worthies, Desmarest fulfilled a similar 
 career, and reached, without infirmities or any grave 
 malady, the age of ninety years. He died on the 
 2oth September 1815. 
 
 "During his protracted lifetime, he saw the Academy 
 twice renewed. Among so large a number of col- 
 leagues he doubtless recognised that there were many 
 who equalled or even surpassed him in enlightenment 
 or in mental power, but he had the happiness to be 
 assured that his name would last as long as that of 
 any one among them." 
 
 For the sake of continuity in the narrative, I have 
 traced the labours of Desmarest from their beginning 
 to their close without adverting to those of his con- 
 temporaries. His views regarding the volcanic origin 
 of Basalt were adopted by a number of good observers, 
 among whom reference may be made to Raspe, 1 
 
 1 R. E. Raspe (1737-1794) had a singularly eventful life. Born 
 in Hanover of poor parents, he obtained his education at the Univer- 
 sities of Gottingen and Leipzig, and obtained an appointment at 
 the latter, where he translated the philosophical works of Leibnitz. 
 After various changes of occupation, he became keeper of the collection 
 of antique gems and medals, and began to study geological subjects. 
 In 1769 he communicated to the Royal Society of London a paper 
 
174 Desmaresfs Contemporaries 
 
 Fortis, 1 Dolomieu, 2 Faujas de St. Fond, Montlosier, 
 and Breislak. 3 But a still more numerous and more 
 
 on the former existence of mammoths in the northern regions, and 
 was afterwards elected an honorary Fellow of the Society. His 
 industry and the wide range of subjects on which he employed his 
 facile pen were truly remarkable. In 1775, after being sent to Italy 
 to collect antiquities and other objects for the Landgrave of Hesse, he 
 was accused of peculation, and was arrested. He succeeded, how- 
 ever, in escaping to England and spent there the remainder of his 
 life. He spoke and wrote English well, and among the works which 
 he published in this country was an interesting little volume entitled 
 An Account of some German Volcanoes and their Productions (1776). 
 Turning his knowledge of minerals to account, he obtained a pre- 
 carious, and apparently not always honest, livelihood as a mining 
 prospector. He is understood to have been the prototype of Douster- 
 swivel in Scott's novel The Antiquary. But his chief title to fame 
 must be admitted to be his authorship of the original Baron 
 Munchauserfs Travels. He had finally to escape to a remote part 
 of Ireland, and died at Muckross in 1794. 
 
 1 J. B. A. Fortis (1741-1803) was born at Padua and was educated 
 for the church in the order of St. Augustine, but was eventually 
 allowed to spend his time in travel, which he did with much success 
 in regard to the natural history and antiquities of Dalmatia and 
 the other tracts visited by him. He was not only a naturalist 
 and learned man, but also a poet and author of verses on love and 
 friendship. He wrote many papers on the geology of different parts 
 of Northern Italy. Having accompanied Desmarest in his excursion 
 through the volcanic parts of that region, he adopted the views of 
 the French geologist as to the origin of basalt, but he indulged his 
 fancy in supposing the heat caused by the eruptions of the Vicentin 
 to have been so great as to raise the temperature of the Adriatic to 
 such a degree as to permit tropical species to live in its waters. His 
 Memoires pour servir a FHistoire Nature lie et principalement a. I'Orycto- 
 graphie de Fltalie et des pays adjacents were published in two volumes 
 at Paris in 1802. 
 
 2 See/0j#rf, p. 254. 
 
 3 For notices of these geologists, see postea, pp. 255-258. 
 
His dislike of Controversy 175 
 
 blatant band, urged on its way by Werner, opposed 
 these doctrines. Although the controversy raged 
 through Desmarest's life, he took, as I have said, no 
 share in it. He made an occasional allusion to the 
 disorder and confusion that had been introduced into 
 a question which in itself was simple enough to those 
 who knew how to look at the actual facts. He 
 asked reproachfully what would become of natural 
 history and mineralogy, if every question were treated 
 as that concerning Basalt had been ? And he wrote 
 somewhat scornfully of the authors who, without 
 having ever undertaken any researches of the kind 
 themselves, ventured in discussing those of others to 
 indulge in unfounded hypotheses. 1 When any belated 
 straggler from the enemy's camp came to consult 
 Desmarest on the subject in dispute, the old man 
 would content himself with the answer, "Go and 
 
 see." 
 
 Leaving this controversy for subsequent considera- 
 tion in connection with its later developments, I will 
 pass from the subject for the present, for the purpose 
 of calling attention in the following chapter to a 
 contemporary event which was one of the most inter- 
 esting features in the scientific life of the latter half 
 of the eighteenth century the rise of the spirit of 
 scientific travel. 
 
 1 See the article "Basalte" in vol. iii. of the Geographic Physique, 
 published 1809. 
 
CHAPTER VI 
 
 THE Rise of Geological Travel Pallas, De Saussure. 
 
 OF all the physical events that happened in the latter 
 half of the eighteenth century, there was probably none 
 so fruitful in fostering, among the civilized countries 
 of the world, an emulation in discovery and research, 
 as the transit of Venus, which occurred in the summer 
 of 1769. To that event we owe the voyages of Cook, 
 and all the rich harvest of results which they added 
 to our knowledge of the geography of the globe. 
 What England did on the ocean, it was reserved for 
 Russia to rival on the land. The Empress Catherine 
 II. had been irritated by the sarcastic remarks made 
 by a French astronomer who had travelled to Russia 
 to observe the previous transit of Venus in 1763, and 
 she is even said to have been at the trouble of refuting 
 them herself. At all events, she resolved to do with- 
 out foreign assistance for the second transit. Deter- 
 mined that the work should be done thoroughly, and in 
 such a way as to redound to the glory of her reign, she 
 commissioned the Academy of Sciences of St. Peters- 
 burg to organize the expedition. This undertaking 
 was conceived in a truly imperial spirit. Not only 
 
Empress Catherine's Survey of Russia 177 
 
 were astronomers sent out for the more immediate ob- 
 jects of the research, but advantage was taken of the 
 occasion to despatch a competent band of observers for 
 the purpose of penetrating into every region of the vast 
 empire, and making known its condition and resources. 
 
 The instructions drawn up for the guidance of the 
 explorers were of the most exhaustive kind. Accurate 
 observations were to be made in the geography and 
 meteorology of each region visited, the positions of 
 the principal places were to be astronomically deter- 
 mined, the nature of the soils, the character of the 
 waters, and the best means of reclaiming the waste 
 places were to be accurately observed. The travellers 
 were to enquire into the rocks and minerals, and to 
 attend to the outer forms and internal composition 
 of the mountains. They were further to carry on 
 careful researches among the plants and animals of 
 each territory, and, in short, to obtain as much accurate 
 information as possible in every department of natural 
 history. Nor were the social problems of life for- 
 gotten. The expedition was further instructed to pay 
 special attention to the various races of mankind met 
 with in the journeys, and to report on their manners, 
 customs, religions, forms of worship, languages, tradi- 
 tions, monuments and antiquities. They were likewise 
 enjoined to take note of the condition of agriculture, 
 of the maladies that affected man and beast, and the 
 best remedies for them, of the cultivation of bees and 
 silk-worms, the breeding of cattle and sheep, and 
 generally of the occupations, arts, and industries of 
 each province. 
 
 A survey of this complete nature, carried over so 
 
178 Pierre Simon Pallas 
 
 vast a region as the Russian Empire, demanded much 
 skill, labour and time. It was fortunately entrusted 
 to a man in every way qualified for the task Pierre 
 Simon Pallas (1741-1811). The whole expedition 
 comprised seven astronomers and geometers, five 
 naturalists and several assistants. Starting from St. 
 Petersburg in June 1768, they traversed the vast 
 empire to its remotest bounds, making many journeys 
 in every direction. After six years of unwearied 
 labour, and almost incredible suffering and privation, 
 during which Pallas had from time to time sent home 
 accounts of his more important observations, he re- 
 turned in July 1774. 
 
 Never before had so large a store of observations 
 in all departments of natural history, extending over 
 so wide a region of the earth's surface, been gathered 
 in so brief a time. Pallas wrote his results in German 
 (his native language, for he was born at Berlin), and 
 sent them home as they were ready. They were 
 published at St. Petersburg between 1772 and 1776, 
 in three quarto volumes. Translated into French, 
 the work afterwards appeared at Paris during the 
 years from 1788 to I793, 1 in five handsome quartos, 
 with a folio atlas of plates. 
 
 Pallas was an accomplished naturalist, and made 
 some original and valuable contributions to zoology. 
 But it is only with his geological work that we are 
 here concerned. One of the geological questions 
 which especially interested him was the occurrence of 
 the remains of huge pachyderms in the superficial 
 
 1 Another edition of this translation appeared in 8 volumes 8vo, 
 and was reprinted at Bale in 1806. 
 
Fossil Pachyderms of Siberia 1 79 
 
 deposits of the north of Siberia. These remains, as 
 far back as the later years of the seventeenth century, 
 had been known to exist, for a trade in the ivory 
 tusks of fossil elephants from the Siberian coasts and 
 rivers had before that time been carried on. The 
 actual bones of these animals were subsequently dis- 
 interred by observers capable of describing their mode 
 of occurrence, so that Pallas had his curiosity much 
 excited by the accounts which had already been pub- 
 lished. There was still much to be found out regard- 
 ing these strange relics of the frozen north, and Pallas 
 determined to investigate the subject in the fullest 
 detail. He kept his eye open for every trace of fossils 
 of any kind, and one of the most valuable parts of his 
 labours is to be seen in the precision with which he 
 chronicles every fossiliferous locality. But the most 
 astonishing feature of his journeys in this respect was 
 the proofs he obtained of the almost incredible num- 
 ber of bones and tusks of the huge pachyderms. The 
 whole vast basin of Siberia lying to the east of the 
 Ural mountains, and north of the Altai chain to the 
 shores of the Arctic Ocean, was found by him to be, 
 as it were, strewn with these remains. He noticed 
 that the bones belonged to species of elephant, rhino- 
 ceros and buffalo, and in one case he saw parts of the 
 carcase of a rhinoceros still retaining its leather-like skin 
 and its short hairs. From the abundance of hair on 
 some parts of the skin of these animals, he inferred that 
 the rhinoceros of Siberia could live in a more temperate 
 climate than its living representatives now enjoy. 
 
 But undoubtedly the most important contribution 
 made by Pallas to geological investigation is to be 
 
180 Pallas 
 
 found in his memoir on the formation of mountains 
 and the changes that have taken place on the globe, 
 particularly with regard to the Empire of Russia. 1 The 
 highest mountains, he remarked, are composed of 
 granite, with various schists, serpentine, grits, and 
 other bedded masses in vertical or highly inclined 
 positions. These formed his Primitive band, and in 
 his opinion were older than the creation of organized 
 beings, for no trace of organic remains was to be 
 found in any part of them. 
 
 The primitive schistose band of the great chains is 
 immediately succeeded by the calcareous band, which 
 consists first of solid masses of limestone, either con- 
 taining no marine productions or only slight traces 
 of them. The thick beds of limestone are placed at 
 high angles and parallel to the direction of the chain, 
 which is also generally that of the schistose band. 
 As they recede from the line of the mountains, the 
 limestones rapidly sink down into a horizontal position, 
 and soon appear full of shells, corals and other 
 marine organisms. These upheaved limestones form 
 the Secondary mountains of Pallas. A third series of 
 rocks, which seemed to him to be the record of some 
 of the latest revolutions of the globe, consists of sand- 
 stones, marls, and various other strata, forming a 
 chain of lower hills in front of the limestone range. 
 To this series of deposits he gave the name of Tertiary 
 mountains. 2 
 
 1 Act. Acad. Set. Imp. Petropolit. 1777, pp. 21-64. 
 
 2 A threefold classification of the rocks was also made by Arduino 
 in Northern Italy and by Lehmann in Germany, as will be more 
 particularly referred to in the following chapter. 
 
His threefold grouping of Rocks 1 8 1 
 
 These geological terms, thus proposed by Pallas, 
 were not of course used by him in their more precise 
 modern definition. We know, for example, that his 
 Tertiary mountains consisted mainly of the younger 
 Palaeozoic sediments which are now called Permian, 
 and that with these ancient formations he included the 
 much younger sands and clays that inclose the remains 
 of mammoth, rhinoceros and other extinct mammals. 
 
 The main value of his observations lies in his clear 
 recognition of a geological sequence in passing from 
 the centre to the outside of a mountain-chain. He 
 saw that the oldest portions were to be found along 
 the axis of the chain, and the youngest on the lower 
 grounds on either side. He recognized also that the 
 sea had left abundant proofs of its former presence 
 on the land, he thought that its level had never been 
 more than 100 fathoms higher than at present, and 
 he supposed that the elevation of the mountains had 
 been caused by commotions of the globe. 1 
 
 We now pass from the Ural chain, which served 
 Pallas as his type of mountain-structure, to another 
 and more famous group of mountains, where, during 
 the same period, another not less zealous explorer 
 was at work. The labours of De Saussure among 
 the Alps mark an epoch, not only in the investi- 
 gation of the history of the globe, but in the relations 
 of civilized mankind to the mountains which diversify 
 the surface of the land. 
 
 Up till towards the end of the eighteenth century 
 
 1 See the summary of Pallas's views given by D'Archiac in his 
 Cours de Paleontohgie Stratigraphique, p. 159, 1862. For a fuller 
 exposition consult Journal de Physique, xiii. (1779), pp. 3 2 9"35* 
 
1 82 Horace-Benedict de Saussure 
 
 mountain-scenery was usually associated in men's 
 minds with ideas of danger, and repulsion. Every 
 reader of English literature will remember passages, 
 alike among poets and prose-writers, wherein the 
 strongest abhorrence is expressed for the high, rugged 
 and desolate regions of the earth. These tracts, 
 which seemed at that time to have in themselves 
 no attractions, were generally looked upon as best 
 seen from a distance, and not to be entered or 
 traversed save on the direst compulsion. 
 
 The first step in the breaking down of this pre- 
 judice, which we all now laugh at, was made by the 
 scientific researches of Horace-Benedict de Saussure 
 (1740-1799), from which we may date the rise of the 
 modern spirit of mountaineering. He it was who first 
 taught the infinite charm and variety of mountain- 
 scenery, the endless multiplicity of natural phenomena 
 there to be seen, and the enthusiasm which the 
 mountain-world will awaken in the heart of every 
 responsive climber. How few among the thousands 
 who every year repair to the Alps, the Pyrenees, 
 the Caucasus, or who find their way to the peaks of 
 the Rocky Mountains and the Sierra Nevada, are 
 aware of the debt they owe to the great geologist of 
 Geneva ! 
 
 De Saussure was born in that city in the year 1740. 
 His career at college was so distinguished that at 
 twenty years of age he became a candidate for a pro- 
 fessorship of mathematics, and at two-and-twenty ob- 
 tained one of philosophy. Trained in physical science, 
 he acquired habits of exactitude in observation and 
 reasoning, which stood him in good stead in the 
 
His love of Mountains 1 8 3 
 
 scientific life to which he eventually devoted himself. 
 Botany was his first love, and after a long and fruitful 
 devotion to other parts of the domain of science, it 
 was to plants that he turned again at last in the 
 closing years of his life. Amidst his laborious cam- 
 paigns in the Alps, the plants of the mountains never 
 lost their charm for him. Among the highest crests, 
 surrounded by all that is most impressive in Nature, 
 and occupied with the profoundest problems in the 
 history of the globe, he would carefully gather the 
 smallest flower and mark it with pleasure in his note- 
 book. 1 
 
 De Saussure's attitude towards his native mountains 
 may be inferred from a few of the sentences with which 
 he prefaces his immortal work. " It is the study of 
 mountains which above all else can quicken the pro- 
 gress of the theory of the earth or geology. The 
 plains are uniform, and allow the rocks to be seen 
 only where these have been excavated by running 
 water or by man. The high mountains, on the other 
 hand, infinitely varied in their composition as in 
 their forms, present gigantic natural sections wherein 
 the order, the position, the direction, the thickness 
 and the nature of the different formations of which 
 they are composed, as well as the fissures which 
 traverse them, can be seen with the greatest clear- 
 ness and at one view. Nevertheless, to no purpose 
 are these facilities of observation offered, if those 
 who propose to study the question do not know 
 how to consider these grand objects as a whole and 
 in their widest relations. The sole object of most 
 iCuvier, " loge de Saussure," Stages, vol. i. p. 411. 
 
184 H. B. de Sans sure 
 
 travellers who call themselves naturalists is to collect 
 curiosities ; they walk, or rather they crawl, with their 
 eyes fixed on the ground, picking up little bits here 
 and there, without aiming at any general observations. 
 They are like an antiquary who at Rome, with the 
 Pantheon and the Colosseum in front of him, should 
 scrape the ground to seek for pieces of coloured 
 glass without ever casting his eyes on the architecture 
 of these superb edifices. It is not that I advise the 
 neglect of detailed observations. On the contrary, I 
 look upon them as the only basis of solid knowledge. 
 But while we gather these details, I desire that we 
 should never lose sight of the great masses, and that 
 we should always make a knowledge of the great 
 objects and their relations, our aim in studying their 
 small parts. 
 
 " But to observe these mighty masses we must not 
 content ourselves with following the high-roads, which 
 nearly always wind through the valleys, and which 
 never cross the mountains, save by the lowest passe. 1 . 
 We must quit the beaten tracts, and climb to the 
 lofty summits, whence the eye can take in at one 
 sweep a multiplicity of objects. Such excursions are 
 toilsome, I admit ; we must relinquish carriages, and 
 even horses, endure great fatigue, and expose ourselves 
 sometimes to considerable danger. Many a time the 
 naturalist, when almost within reach of a summit on 
 which he eagerly longs to stand, may doubt whether he 
 has still strength enough left to reach it, or whether he 
 can surmount the precipices which guard its approaches. 
 But the keen fresh air which he breathes makes a 
 balm to flow in his veins that restores him, and the 
 
His geological opinions 185 
 
 expectation of the great panorama which he will enjoy, 
 and of the new truths which it will display to him, 
 renews his strength and his courage. He gains the 
 top. His eyes, dazzled and drawn equally in every 
 direction, at first know not where to fix themselves. 
 By degrees he grows accustomed to the great light, 
 makes choice of the objects that should chiefly occupy 
 his attention, and determines the order to be followed 
 in observing them. But what words can describe the 
 sensations or the ideas with which the sublime spectacle 
 fills the soul of the philosopher. Standing as it were 
 above the globe, he seems to discover the forces that 
 move it, at least he recognizes the principal agents 
 that effect its revolutions." 
 
 De Saussure spent his life among the scenes he so 
 enthusiastically described, studying the meteorology no 
 less than the geology of the Alps. As regards the 
 geological structure of mountains and the origin of 
 their component rocks, however, he seems hardly 
 to have advanced beyond the ideas of Pallas. He 
 believed, with Werner, that the central granite had 
 resulted from deposition and crystallization in the 
 waters of a primeval ocean. The vertical or highly 
 inclined limestones, and other strata flanking the 
 granite, were for a long time regarded by him as still 
 in the position in which they were originally deposited. 
 It was only when he found among these strata layers 
 of sand and rounded pebbles that he was driven to 
 admit that there had been some disturbance of the 
 earth's surface. 
 
 Like Pallas and his contemporaries generally, De 
 Saussure never attempted to set down his observations 
 
1 86 H. B. de Saussure 
 
 of the distribution of the rock-formations upon a 
 map, nor, though he had before him the excellent 
 sections constructed by Lehmann, to which reference 
 will be made in the following chapter, did he give 
 definite expression to his ideas of the mutual relations 
 of the rocks by constructing a horizontal section even 
 of the most general and diagrammatic kind. It is 
 thus a somewhat laborious task to gather from his 
 Voyages dans les Alpes what precisely were the opinions 
 he held in regard to tectonic questions. To him, 
 however, so far as I have been able to discover, we 
 owe the first adoption of the terms geology and 
 geologist. This science had formed a part of miner- 
 alogy, and subsequently of physical geography. The 
 earliest writer who dignified it with the name it now 
 bears was the first great explorer of the Alps. 1 
 
 De Saussure's theoretical views underwent some 
 modification during the prolonged period occupied by 
 the publication of his work, though they seem never 
 
 1 In the year 1778 there appeared at the Hague the first 
 imperfect edition of De Luc's Lettres Physiques et Morales sur les 
 MontagneSy in the introduction to which the author states that 
 for the science that treats of the knowledge of the earth he 
 employs the designation of Cosmology. The proper word, he 
 admits, should have been Geology, but he "could not venture 
 to adopt it because it was not a word in use" (Preface, p. viii.). 
 In the completed edition of his work, published the next year, 
 he repeats his statement as to the use of the term Cosmology, 
 yet he uses Geology in his text notwithstanding (vol. i. pp. 4, 5). 
 In the same year (1779), De Saussure employs the term Geology 
 in his first volume without any explanation or apology, and 
 alludes to the geologist as if he were a well-known species of 
 natural philosopher. (See his Discours Preliminaire, pp. vii., ix., 
 xiv., xvi.) 
 
His mews on plicated strata 187 
 
 to have advanced much, notwithstanding his constantly 
 increasing experience and the enormous amount of 
 observations amassed by him regarding the rocks of 
 the mountains. 
 
 His first quarto volume appeared in 1779, * ne secon d 
 in 1786, the third and fourth in 1796. There was 
 thus an interval of fifteen years during which, with 
 unwearied industry, he continued to traverse the Alps 
 from end to end, and to multiply his notes regarding 
 them. Yet he does not seem ever to have reached 
 any broad conceptions of stratigraphical succession, 
 or of orographical structure. When he came upon 
 strata crumpled and doubled over upon themselves, 
 he thought of crystallization in place as the cause of 
 such irregularities. The idea of subterranean disturb- 
 ance would sometimes occur to him, but for many 
 years he dismissed it with an expression of his in- 
 credulity, remarking that " if the underground fires 
 had been able to upraise and overturn such enormous 
 masses, they would have left some trace of their 
 operation, but that after the most diligent search he 
 had been unable to discover any mineral or stone 
 which might even be suspected to have undergone 
 the action of these fires." * He had thus no concep- 
 tion of any operation of nature other than that of 
 volcanoes, which could produce great disturbances of 
 the terrestrial crust. Not only had he met with no 
 trace of any igneous rock in the Alps, but the granite 
 veins which he found traversing a schist, and which 
 he at once regarded as throwing light on the origin 
 of that rock, were believed by him to be almost 
 1 Voyages dans les Alpes y vol. iii. (1796) p. 107. 
 
1 88 H. B. de Saussure 
 
 demonstrably due to infiltration, as the granite itself 
 had in his opinion been formed from crystallization 
 in the waters of the ancient ocean. 1 
 
 Even when he found the vertical conglomerate of 
 Valorsine, and recognized that it must have been 
 originally deposited horizontally, he refrained from 
 hazarding a conjecture as to the reason of its position. 
 " We are still ignorant," he says, " by what cause 
 these rocks have been tilted. But it is already an 
 important step, among the prodigious quantity of 
 vertical strata in the Alps, to have found certain 
 examples which we can be perfectly certain were formed 
 in a horizontal position." 2 
 
 An important part of De Saussure's work among 
 the Alps deserves special recognition. Profoundly im- 
 pressed by the power of running water in the sculpture 
 of the mountains, he ridiculed the notion that the 
 valleys had been carved out by the sea. He showed 
 conclusively that they could only have been excavated 
 by melted snow, rain and rivers. He appealed to any 
 map that might first come to hand in corroboration 
 of his opinion that the valley-system of a country 
 is intimately connected in origin with the system of 
 drainage. 3 Hutton quotes largely from the Voyages 
 dans les Alpes in support of this doctrine, which he 
 made so essential a part of his theory of the Earth, 
 and which he derived from the illustrious geologist 
 of Switzerland. 
 
 It is interesting to notice that, among the agenda 
 which De Saussure inserted at the close of his last 
 
 1 Vol. i. pp. 533 et seq. 2 Vol. ii. 690. 
 
 3 Vol. ii. 920. 
 
His petrographical studies 189 
 
 volume, as the fruit of his long experience, he gives 
 a chapter of suggestions as to what should be looked 
 for in regard to organic remains among the rocks. 
 Some of these suggestions are full of sagacity, and 
 show that, though he had not followed them in his 
 own researches, he recognized the importance of the 
 advice he was giving. One of his admonitions was 
 " to ascertain whether certain shells occur in the older 
 rocks but not in the later, and whether it is possible 
 by their means to fix the relative ages and eras of 
 appearance of the different species." Another recom- 
 mendation is " to compare exactly the fossil bones, 
 shells, and plants with their living analogues and to 
 determine whether they differ from these." * 
 
 One of the most interesting features of De Saussure's 
 work is exhibited in the care with which he equipped 
 himself for the study of the rocks of the region that 
 he undertook to examine and describe. Petrography 
 was at that time in a very embryonic condition. Lin- 
 naeus and Wallerius had made a beginning in the 
 definition of rocks, but Werner's labours had hardly 
 begun. The Swiss naturalist set himself with his usual 
 ardour to the study, into which he introduced his ac- 
 customed order and precision. Among other aids in 
 his researches, he devised a series of experiments in 
 fusion, in order to determine for himself the probable 
 origin of different rocks, and especially to enable him 
 to decide whether certain varieties could be produced 
 by the melting of others. It will be remembered that 
 Desmarest had propounded the doctrine that the basalts 
 of Auvergne had been formed by the fusion of the 
 1 Vol. iv. p. 505. 
 
190 H. B. de Sans sure 
 
 underlying granite by volcanic fire. De Saussure, when 
 he began to study these questions, was astonished to 
 discover how little had been done in the way of ex- 
 perimental research into the nature of rocks. He 
 selected various Swiss granites, and found that in no 
 instance could he reduce them by fusion into basalt. 
 In case there might be any deficiency in the granites of 
 his own country, he tried the effects of a high tem- 
 perature on pieces of granite which he had himself col- 
 lected in Auvergne, but equally without success. He 
 then experimented on a granite containing abundant 
 schorl, and obtained a black vesicular glass sprinkled 
 with the white grains of infusible quartz. He next 
 took specimens of different porphyries, and though he 
 got a compact black enamel, nothing appeared in the 
 least resembling basalt, whence he concluded that it 
 could not be from the natural fusion of such rocks 
 as these that basalt was derived. 1 
 
 These experiments are especially interesting, as they 
 mark the earliest beginnings of experimental geology. 
 The results obtained from them were negative, and 
 De Saussure did not advance further along the path 
 he had thus opened into a domain which was destined 
 in future to become so fruitful. But his name must 
 ever be had in honour for the share he took in estab- 
 lishing the use of direct experiment in the elucidation 
 of geological problems. He did not live to put in 
 practice the directions which he left for the further 
 exploration of the Alps by those who should come 
 after him. A disease, which perhaps took its rise from 
 the fatigues and privations of his life among the 
 1 Vol. i. p. 122-127. 
 
His influence 191 
 
 mountains, began to increase upon him after his 
 fiftieth year. It was aggravated by anxiety on account 
 of the effect of the French Revolution on his private 
 resources. After three successive strokes of paralysis 
 he died in 1799 at the age of fifty-nine years. 
 
 De Saussure was the first and most illustrious of 
 that distinguished band of geologists which Switzer- 
 land has furnished to the ranks of science. To his 
 inspiration and example we owe the labours of Merian, 
 Escher von der Linth, Studer, Favre, and the later 
 and living observers who have so diligently and 
 successfully unravelled the complicated structure of 
 the Alps. His descriptions of a great mountain-chain 
 form admirable models of careful observation and 
 luminous narrative. Though he did not add much 
 to the advancement of geological theory, he contributed 
 largely to the stock of ascertained fact, which was so 
 needful as a basis for theoretical speculation. The 
 data which he collected became thus of the utmost 
 service to those who had to work out the principles 
 of geology. To Hutton, for example, they supplied 
 many admirable illustrations of the geological processes 
 on which he based his Theory of the Earth. It was 
 under the guidance of the great Swiss observer that 
 the Scottish philosopher stood in imagination on the 
 summit of the Alps, and watched from that high 
 tower of observation the ceaseless decay of the moun- 
 tains, the never-ending erosion of the valleys, and that 
 majestic evolution of topography which he so clearly 
 portrayed. Among the illustrious men who contri- 
 buted to plant the foundations of geology, an honoured 
 place must always be assigned to De Saussure. 
 
CHAPTER VII 
 
 HISTORY of the Doctrine of Geological Succession. Arduino, 
 Lehmann, Fiichsel, Werner. 
 
 IN the gradual growth of knowledge regarding the 
 history of our globe, it is surprising how late men 
 were in realising that this knowledge must be based 
 not on mere speculation, but on patient investigation 
 of what evidence can be gathered from the structure 
 of the planet itself. Slowly and laboriously the truth 
 was reached that the rocks which form the terrestrial 
 crust bear witness to the passage, not of one or two, 
 but of a whole series of revolutions, that these changes 
 occupied vast intervals of time, and that while they 
 varied indefinitely in their local effects from one region 
 to another, they were but incidents in one vast onward 
 march of development which embraced the whole 
 globe within its influence. What we now know as 
 the doctrine of geological succession, in other words, 
 the history of the evolution of the earth, during a 
 prolonged series of ages up to the present time, took 
 shape with extreme slowness, each generation adding 
 a little to the basis of fact and to the superstructure 
 of inference. 
 
Slow growth of Geological Chronology 193 
 
 There were in especial two lines of investigation 
 along which progress could be made. On one of 
 these, the various masses of rock that are visible over 
 the surface of the globe had to be studied with a 
 view to the determination of their origin and sequence. 
 On the other line, the details of these rock-masses, 
 and more particularly of the sedimentary series, had 
 to be worked out, and their organic contents to be 
 noted, in order to ascertain how far the living creatures 
 of older times differed from those of the present. 
 The former of these two branches of research naturally 
 came to be pursued first. It is by far the more ob- 
 vious of the two, and considerable progress had to be 
 made in it before the very possibility of the second 
 line of enquiry could be recognised and pursued. 
 
 We have seen that with all his sagacity and insight, 
 Guettard gave no indication that he had any ideas as to 
 the chronological relations of the various groups of 
 strata which he included in his a bands." Neither 
 he nor his contemporaries ventured to draw geological 
 sections. We have found that even De Saussure and 
 Pallas, though they saw that the rocks of the central 
 part of the mountain-chains are older than those of 
 their flanks, did not definitely express their ideas on 
 this subject in graphic form. Desmarest had clearly 
 perceived the evidence for a long sequence of volcanic 
 eruptions in Central France, but he never applied this 
 evidence towards an elucidation of the general history 
 of the globe as a whole. Buffon too had vividly 
 realised the pregnant idea that the earth has passed 
 through a long evolutional history whereof the monu- 
 ments are to be gathered from the structure of the 
 
194 Early writers John Strachey 
 
 planet itself. But though he worked out this idea 
 with great logical acumen and brilliant rhetoric, he 
 had only a slender groundwork of ascertained fact on 
 which to base his pictures of the successive stages 
 through which the earth has passed. Such a ground- 
 work could not be laid down without much patient 
 detailed observation of the rocks, and a comparison of 
 the records afforded by them in different countries. 
 Yet even in Buffon's time the first seeds of Strati- 
 graphy had been sown which, before the end of the 
 eighteenth century, were to germinate in so wide an 
 expansion of geological theory. 
 
 In tracing the history of the idea of a chronological 
 sequence among the rocks of the earth's crust it is 
 interesting to mark its independent origination in 
 different countries. In regions where minerals, more 
 especially coal-seams, had long been worked it was 
 familiar knowledge that a certain definite order could 
 be traced among the rock-formations. Thus in Eng- 
 land, prolonged mining in the coal-fields led to a clear 
 recognition not only of a local order of arrangement, 
 but of a sequence which might be capable of wide 
 application. The first writer in England whose obser- 
 vations on this subject deserve to be cited is John 
 Strachey, who contributed two papers to the Philosophi- 
 cal Transactions in the years 1719 and 1725, in which 
 he recognised the sequence of the geological formations 
 in the south-west of the country, enumerating in their 
 proper order the various leading subdivisions of the 
 stratigraphical series from the Coal to the Chalk. He 
 likewise recorded the important fact that while the 
 Coal-strata are all more or less inclined, the overlying 
 
Arduino, Lehmann 195 
 
 formations from the Red Marl upwards lie horizontally 
 across their edges. 1 
 
 In Italy the name of Giovanni Arduino (1713-1795) 
 is deservedly held in honour for the share which during 
 his long life he took in upholding the reputation of 
 the illustrious Italian school of geology. Born near 
 Verona, he became inspector of mines in Tuscany 
 and finally professor of Mineralogy and Metallurgy at 
 Venice. Among his contributions to science it may 
 be noted that he classified the rocks of the north of 
 Italy as Primitive, Secondary, Tertiary and Volcanic. 
 The first of these divisions included the schists and 
 associated masses which occupy the core of the moun- 
 tains and contain no organic remains. The second 
 comprised limestones, marls, shales and other stratified 
 sedimentary materials, many of which are crowded with 
 fossils. The third was made up of generally looser 
 detritus, derived from the disintegration of the other 
 rocks, and sometimes full of remains of terrestrial 
 plants and animals. The volcanic group consisted of 
 lavas and tuff accumulated by repeated eruptions and 
 inundations of the sea. Thus to Arduino geology is 
 indebted for the threefold classification of the rocks 
 of the earth's crust, which amid all the changes of 
 nomenclature, has survived down to the present time. 
 
 Johann Gottlob Lehmann (died 1767) published 
 at Berlin in 1756 a little duodecimo volume, roughly 
 printed on poor paper, extending to 240 pages, and 
 bearing the title Versuch einer Geschichte von Flotz- 
 Gebiirgen, etc. This unpretending treatise must be 
 ranked as one of the classics of geological literature. 
 l Phil. Trans, xxx. (1719) p. 968 ; xxxi. p. 395. 
 
196 Lehmann 
 
 It gives the results of the author's own observations 
 among the rocks of the Harz and the Erzgebirge. 
 Like Arduino he recognized three orders of mountains, 
 ist, Those which appeared coeval with the making of 
 the world ; 2nd, those which arose from a general 
 alteration of the ground ; and 3rd, those which have 
 been formed from time to time by local accidents. 
 The first order is distinguished not only by the 
 greater height of its members, but by their internal 
 structure. The rocks are less various, their strata 
 are not horizontal but vertical or inclined, and their 
 layers are neither so weak nor so multifarious as those 
 of the other groups. Nor are they mere superficial 
 deposits, but they plunge down into unknown depths 
 into the earth's interior. The second order, or Flotz- 
 gebirge, are of much younger date, and have arisen 
 from the successive deposit of sediments from water 
 that once covered their sites, these sediments being 
 now seen in flat sheets or strata, piled above each 
 other to no great height. Lehmann showed that 
 these sedimentary deposits contain abundant petrifac- 
 tions, such as remains of wild animals, shells, plants 
 and trees. He gave a number of sections to show the 
 order in which the strata succeed each other, remarking 
 that the coarser sediments were generally lowest, while 
 limestone came at the top. His profiles of the suc- 
 cession of strata showed a remarkable grasp of some 
 of the essential features of tectonic geology. It is 
 singular that these suggestive examples should not 
 have had more imitators during the latter half of 
 the eighteenth century. Nothing could be more 
 precise and distinct than Lehmann's demonstration 
 
Fuchsel 197 
 
 of the stratified nature and aqueous origin of the 
 younger formations of the earth's crust, or his proofs 
 that the strata succeed each other in a definite order 
 in the region with which he was acquainted. 
 
 Contemporary with Lehmann, and though less fre- 
 quently quoted, worthy of a still higher place in the 
 bede-roll of geological worthies was George Christian 
 Fuchsel (I722-I773). 1 This remarkable man was 
 the son of a baker in Ilmenau, at the northern 
 foot of the Thuringian Forest. He studied at the 
 Universities of Jena and Leipzig, and having from 
 an early date addicted himself to minerals and rocks, 
 he was lucky enough to find a seam of coal at 
 Mtthlberg, near Erfurt, and still more fortunate to 
 receive from the proprietor of the ground a reward 
 of 200 crowns for the discovery. At Erfurt he took 
 his degree of Doctor of Medicine, and eventually 
 became physician to the Prince of Rudolstadt. He 
 lived to the age of only fifty-one, and died in the 
 year 1773. 
 
 His position at Rudolstadt was favourable for the 
 cultivation of his taste for geological pursuits. To 
 the south rose the ancient rocks of the Thuringer 
 Wald, flanked by the great series of Permian and 
 Triassic formations, regularly superposed upon each 
 other, and cut out into valleys by the rivers that 
 drain the mountain range. In the year 1762, when 
 he was forty years of age, he published one of the 
 
 1 For the personal data here given I am indebted to a brief notice 
 by C. Keferstein in the Journal de Geo/ogie, vol. ii. (1830), p. 191, 
 and to his account of Fuchsel in his Geschichte und Litteratur der 
 Geognosie (1840), p. 55 seq. 
 
198 Fuchsel 
 
 most remarkable treatises which up to that time had 
 been devoted to the description of the actual structure 
 and history of the earth. It was in Latin, and, under 
 the title of " A History of the Earth and the Sea, 
 based on a History of the Mountains of Thuringia," 
 appeared in the Transactions of the Electoral Society 
 of Mayence, established at Erfurt. 1 It was illustrated 
 with a geological map and sections of the country. 
 Eleven years later he published in German a Sketch of 
 the most Ancient History of the Earth and Man, which 
 contained a further development of his geological 
 
 views. 2 
 
 These views were founded on the author's own 
 observations in the region where he Jiad been born 
 and passed his life. He recognized as clearly as 
 Lehmann, and with more accuracy of detail, the 
 sequence of stratified rocks resting in gently-inclined 
 strata against the older upturned masses of the 
 mountains. He noted the position of the Coal with 
 its exotic plants, followed by the copper-bearing shales, 
 Zechstein, mottled sandstone, marls, gypsum, and 
 finally the Muschelkalk. 
 
 Taking no limited or parochial view of the pheno- 
 mena that presented themselves before his eyes, he 
 connected the history of his little principality with 
 that of the whole globe. In the order of succession 
 
 1 " Historia terrae et maris, ex historia Thuringiae per montium 
 descriptionem erecta " (Trans. Elect. Soc. Mayence, vol. ii. pp. 
 44-209). The map was the first detailed geognostical and petro- 
 graphical map of a large district in Germany, and the sections 
 were excellent for their time. 
 
 2 Entwurf zu der altesten Erd- und Memchengeschichte, 275 pages, 
 8vo, 1773. 
 
His sagacious geological mews 199 
 
 ot the rocks around him, he saw the records of a 
 series of changes which the earth had once under- 
 gone. These changes were conceived by him to have 
 been of no abnormal kind, but to have resembled 
 those which might quite possibly occur now, for, in 
 his opinion, our planet had always presented pheno- 
 mena similar to those of the present time. He saw 
 that the existing dry land was in large measure formed 
 of strata that had once been laid down on the floor 
 of the sea, like the sandstones, marls and limestones 
 with which he was familiar. Rising from underneath 
 these strata, the older and inclined rocks of the 
 mountains appeared to him as the relics of a more 
 ancient continent, which had in like manner been 
 built up of marine sediments. He believed that the 
 tilted, highly-inclined positions of these rocks were 
 due to their having tumbled down into the hollow 
 interior of the earth. 
 
 Fiichsel, with much sagacity, not only interpreted 
 the origin of individual strata, but divined that a 
 continuous series of strata of the same composition con- 
 stitutes a formation, or the record of a certain epoch in 
 the history of the globe, thus anticipating a doctrine 
 which afterwards took a prominent place in the system 
 of Werner. All these sediments were originally 
 deposited horizontally. Where they have been placed 
 in inclined positions, the alteration was, in his opinion, 
 to be attributed to some subsequent disturbance, such 
 as the effects of earthquakes or oscillations of the 
 ground. To earthquakes also he assigned the pro- 
 duction of the rents which, being filled from above, 
 now form veins in the rocks. It was his opinion 
 
200 Fuchsel 
 
 that the earthy passage-beds between formations 
 mark intervening periods of disturbance. 
 
 The Muschelkalk in Fttchsel's district forms the 
 highest of the Secondary formations, and is succeeded 
 by the various alluvial deposits. These youngest 
 accumulations, containing only terrestrial remains, were 
 looked upon by him as having arisen from the action 
 of a great deluge. 
 
 This singularly shrewd observer deserves further 
 to be remembered for the place which he assigned 
 to organic remains in his theoretical views of the past 
 history of the earth. He clearly recognized these 
 objects as relics of once living things. He saw that 
 the Coal was distinguished by its land-plants, the 
 Zechstein by its gryphites, the Muschelkalk by its 
 ammonites ; further, that some formations contained 
 only marine remains, others only terrestrial, and thus 
 that the latter point to the neighbourhood of ancient 
 land, while the former indicate the presence of the sea. 
 
 The clear and detailed evidence brought forward 
 by Lehmann and Fuchsel, that the materials of the 
 terrestrial crust had not been thrown down at random, 
 but succeeded each other in a certain definite order, 
 and contained a record of former processes and 
 changes, like those in progress now, ought to have 
 given at once a great forward impetus to the study 
 of the history of the earth. Lehmann's volume, 
 however, was not in itself attractive, and Fiichsel's 
 first essay, though by far the most detailed and philo- 
 sophical treatise on the subject that had yet appeared, 
 was written in Latin, and buried in the publications 
 of an obscure Society. Fuchsel himself lived quietly 
 
Abraham Gottlob Werner 201 
 
 in a little town, with no disciples to spread his 
 doctrines, so that his very name remained hardly 
 known even in Germany, while other and much inferior 
 writers achieved a wide reputation. His writings 
 seem to have dropped out of sight, until they were 
 unearthed and brought to notice fifty-seven years after 
 his death by Keferstein. The seed sown in Germany 
 by Lehmann and Fiichsel was thus long in springing 
 into abundant growth. During the remainder of 
 the century the idea of geological succession was pro- 
 claimed, indeed, from the housetops, but it was so 
 mingled with fanciful hypothesis, that its truth and 
 real value were almost lost sight of. 
 
 We come now to the time of the advent of a man 
 who bulks far more largely in the history of geology 
 than any of those with whom up to the present we 
 have been concerned a man who wielded an enor- 
 mous authority over the mineralogy and geology of 
 his day. Through the loyal devotion of his pupils, 
 he was elevated even in his lifetime into the position 
 of a kind of scientific pope, whose decisions were 
 final on any subject regarding which he chose to 
 pronounce them. During the last quarter of the 
 eighteenth century, by far the most notable figure in 
 the ranks of those who cultivated the study of min- 
 erals and rocks was unquestionably Abraham Gottlob 
 Werner (1749-1817). 
 
 The vast influence which this man wielded arose 
 mainly from his personal gifts and character, and 
 especially from the overmastering power he had of 
 impressing his opinions upon the convictions of his 
 hearers. It was an influence of a curiously mingled 
 
202 IVerner 
 
 kind. From one point of view, Werner appears to 
 us as the enthusiastic teacher, drawing men from all 
 countries under his spell, and kindling in them much 
 of his own zeal for the study of minerals and rocks. 
 In another aspect, he stands out as the dogmatic 
 theorist, intolerant of opinions different from his own, 
 training his pupils in an artificial and erroneous system, 
 and sending them out into the world not patienty 
 to investigate nature, but to apply everywhere the 
 uncouth terminology and hypothetical principles which 
 he had taught them. 
 
 Though he himself mixed but little publicly in 
 the dispute, he was directly the cause of the keen 
 controversy over the origin of basalt, the echoes of 
 which had hardly ceased when some of the older 
 geologists of our day were born. I have myself 
 known a number of men who remembered well the 
 acrimony of the warfare, and some of whom even 
 played the part of combatants in the struggle. Werner 
 had a large following. He was undoubtedly the most 
 popular teacher of the science of minerals and rocks 
 in his time. His services to mineralogy were great, 
 and have always been freely admitted. By the partiality 
 of his pupils and friends he was also raised to the 
 highest eminence as a teacher of geology, and was 
 even looked up to as the founder of that science. 
 The noise of conflict, and the plaudits of enthusiastic 
 disciples have now long been silent. We can calmly 
 consider what Werner did, in what state he found the 
 science of the rocks, and in what condition he left 
 it. As the result of my own investigation in this 
 subject I have been compelled to arrive at the con- 
 
His childhood 203 
 
 elusion that, although he did great service by the 
 precision of his lithological characters and by his 
 insistence on the doctrine of geological succession, yet 
 that as regards geological theory, whether directly by 
 his own teaching, or indirectly by the labours of his 
 pupils and followers, much of his influence was 
 disastrous to the higher interests of geology. The 
 career of such a man, so full of contradictions, so 
 preponderant in the studies to which it was devoted, 
 and so momentous in its effects upon the progress 
 of science in his own generation, merits the careful 
 consideration of all who would realise how geology 
 has gained its present place. 
 
 Werner was born on 25th September 1749 at 
 Wehrau on the Queiss in Upper Lusatia. 1 His 
 ancestors had been engaged in the iron industry of 
 that region of Germany for some 300 years. His 
 father was inspector of Count Solms' foundry, and 
 at one time it seemed as though the future mineralogist 
 were to carry on, in the same profession, the traditions 
 of the family. From infancy he was familiar with 
 stones. When still hardly able to speak, it was one 
 of his favourite amusements to break down pieces of 
 sandstone and marl. After he had begun to learn 
 his alphabet, his father, as a reward for proficiency 
 in his lessons, would allow him to look over a small 
 collection of minerals which he kept in a box, and 
 
 1 For the biographical details given in this sketch I am indebted 
 partly to the " Kurzer Nekrolog Abraham Gottlob Werners," by 
 K. A. Blode, in the Memoirs of the Mineralogical Society of Dresden, 
 vol. ii. (1819), p. 249, and partly to the Eloge on Werner by Cuvier. 
 Blode, who had access to family documents, gives 1749 as the year 
 of Werner's birth; Cuvier and other authorities make it 1750. 
 
204 Werner 
 
 would talk to him about them, their origin and their 
 uses. Late in life Werner could vividly recall the 
 very minerals that were the playthings of his child- 
 hood various ores and spars, as well as some varieties 
 of which his father did not know the names. When 
 he could read, his favourite books were lexicons of 
 mining and manufactures, wherein he specially selected 
 the articles on mineralogy. His tendencies, thus early 
 shown, were further fostered by his father, who in 
 hours of leisure would entertain him with stories of 
 the mines. 
 
 In his tenth year the boy went to school at the 
 old fortified town of Bunzlau in Silesia, and after a 
 few years returned in 1764 to assist his father and 
 become controller of the smelting houses at Wehrau. 
 But the aspirations he had formed to devote himself 
 to minerals seem at last to have grown too strong 
 to be resisted, so that after doing his duty at the 
 foundries for five years, he resolved to betake himself 
 in 1769 to the Mining Academy of Freiberg, which 
 had been founded two years before, and of the 
 attractions of which he had no doubt heard much. 
 Amid what was there thoroughly congenial to him, 
 he threw himself with enthusiasm into the work of 
 the school, not only availing himself of all the formal 
 instruction in the art of mining to be had from the 
 teachers, but visiting all the chief Saxon mines, 
 especially those of most importance in the Freiberg 
 district, descending the shafts, joining in the manual 
 labour of the miners, and thus making himself master 
 of the whole art of mining, below ground as well 
 as above. His zeal and capacity were soon recognized 
 
His education 205 
 
 by the officials at Freiberg, and before he had been 
 long there he was offered a place in the Saxon Corps 
 of Mines. He was not unwilling to accept the 
 appointment, but determined first of all to prosecute 
 a wider range of study for a few years at the 
 University of Leipzig. 
 
 Accordingly, after some two years spent in mining 
 pursuits, Werner went to Leipzig in the spring of 
 the year 1771, and for the next two years devoted 
 himself almost entirely to the study of law. In his 
 third and last year at the University, he seems to 
 have taken up a miscellaneous series of subjects, 
 especially modern languages, but he settled down at 
 last to the prosecution of his first love mineralogy ; 
 and with such industry and enthusiasm did he pursue 
 his study, that while in his twenty-fifth year, and still 
 a " student of the science and law of mining," he 
 published his first essay a little duodecimo of 300 
 pages, on the external characters of minerals. 1 We 
 can imagine the astonishment and delight of the lovers 
 of mineralogy when they first got hold of this treatise, 
 and found there, instead of the miscellaneous, isolated, 
 and heterogeneous observations to which they were 
 accustomed, an admirably ordered method and a clear 
 marshalling and co-ordination of facts, such as had 
 never before been seen in mineralogical literature. 
 
 On leaving the University of Leipzig, Werner went 
 back to his home by the Queiss. It seemed as though 
 the authorities at Freiberg, who at one time were so 
 
 1 " Von den ausserlichen Kennzeichen der Fossilien, abgefasst vdh 
 Abraham Gottlob Werner, Der Bergwerks-Wissenschaften und 
 Rechte Beflissenen," Leipzig, 1774. 
 
20 6 Werner 
 
 anxious to secure his services, had now forgotten his 
 existence. He had heard nothing more of the proposal 
 to engage him, and he began to arrange his plans for 
 the future. But the officials, though slow in their 
 movements, had not lost sight of him. They had 
 made note of his progress at Leipzig, and especially of 
 his admirable little book, and at last in February 1775, 
 to his own astonishment, Werner received a call from 
 them to become Inspector and Teacher of Mining and 
 Mineralogy in the Freiberg Mining Academy at a 
 yearly stipend of 300 thalers. He thus attained before 
 he was twenty-six the position in which he spent the 
 rest of his life and achieved his great fame. For 
 some forty years he continued in the same appoint- 
 ment. By his genius he raised the Mining School 
 from a -mere local seminary, founded for the training 
 of a few Saxon miners, to the importance of a great 
 academy or university, to which as in mediaeval times, 
 his renown as a teacher drew pupils from all corners 
 of the civilized world. Men advanced in years, as 
 well as youths, sometimes even men of science already 
 distinguished, betook themselves to the acquisition of 
 German that they might attend the lectures of the 
 great oracle of geology. 
 
 The life of such a man, seldom tempted to stir from 
 home, immersed in the daily discharge of the duties 
 of his office, and only varying from year to year the 
 subject of his prelections, offers little incident to the 
 biographer. Moreover, though he precociously began 
 so young as an author, he wrote merely a few short 
 treatises and papers in journals, thus leaving hardly any 
 personal memorial behind him. It is from the writings 
 
His figure and character 207 
 
 of his pupils that we chiefly learn what manner of man 
 he was, and what were the special characteristics of his 
 teaching. 
 
 From the portrait of him prefixed to one of his 
 works, 1 we gather that his large keen eyes looked out 
 beneath a broad and high forehead, over which his 
 hair was dressed in the formal wig-fashion of the day, 
 and turned up in large curls on either side. The 
 round, smooth-shaven face had, as its most conspicuous 
 feature, a mouth in which, while the firm lips denoted 
 decision of character, the upward curve on either side, 
 combined with a slight dimpling of the cheeks, gave 
 the impression of great sweetness of disposition, with 
 a touch of humour, and a certain degree of timidity. 
 There is moreover a notable trimness of person, 
 indicative of the exceeding orderliness of his whole 
 nature. 
 
 His personal charm must have been altogether 
 remarkable. Cuvier tells us with what paternal fond- 
 ness Werner was accustomed to treat his pupils. 
 There was no sacrifice of time or energy which he 
 would not make for their sake, even his slender purse 
 was at their service, if they ever stood in need of 
 pecuniary help. When the students crowded round 
 him, so that only a portion of them could conveniently 
 see and hear his demonstrations, he would divide them 
 and repeat his lecture. 2 
 
 l New Theory of the Formation of Veins. Translated by Charles 
 Anderson, M.D. Edinburgh, 1809. 
 
 2 There is an enthusiastic account of Werner as a teacher by one 
 of his pupils, C. A. Bottiger : " Uber Werners Umgang mit seinen 
 Schiilern," Auswahl. Gesellsch. Mineralog. Dresden, Band ii. p. 305 
 (1819). 
 
2o8 Werner 
 
 His manner of discourse also was so attractive and 
 stimulating that he riveted the attention of his pupils, 
 incited them to pursue the studies that he loved, and 
 fired them with a desire to apply his methods. Osten- 
 sibly he had to teach mineralogy a science which in 
 ordinary hands can hardly be said to evoke enthusi- 
 asm. But Werner's mineralogy embraced the whole 
 of Nature, the whole of human history, the whole 
 interests and pursuits and tendencies of mankind. 
 From a few pieces of stone, placed almost at random 
 on the table before him, he would launch out into 
 an exposition of the influence of minerals and rocks 
 upon the geography and topography of the earth's 
 surface. He would contrast the mountainous scenery 
 of the granites and schists with the tamer landscapes of 
 the sandstones and limestones. Tracing the limits of 
 these contrasts of surface over the area of Europe, he 
 would dwell on their influence upon the grouping and 
 characteristics of the nations. He would connect, in 
 this way, his specimens with the migration of races, the 
 spread of languages, the progress of civilization. He 
 would show how the development of the arts and 
 industries of life had been guided by the distribution 
 of minerals, how campaigns, battles, and military 
 strategy as a whole, had been dependent on the same 
 cause. The artist, the politician, the historian, the 
 physician, the warrior were all taught that a knowledge 
 of mineralogy would help them to success in their 
 several pursuits. It seemed as if the most efficient 
 training for the affairs of life were obtainable only at 
 the Mining School of Freiberg. 
 
 By such continual excursions into domains that 
 
Character of his teaching 209 
 
 might have been thought remote enough from the 
 dry study of minerals, and by the clear and confident 
 method, playful vivacity and persuasive eloquence with 
 which they were conducted, Werner roused his hearers 
 to a high pitch of enthusiasm. No teacher of geo- 
 logical science either before or since has approached 
 Werner in the extent .of his personal influence, or in 
 the breadth of his contemporary fame. 
 
 Let us now inquire what were the leading character- 
 istics of his doctrines, and what permanent influence 
 they exerted upon the progress of the science of his 
 time. His brilliance and discursiveness might attract 
 and retain large audiences, but his lectures must have 
 possessed more solid and enduring qualities, which 
 inspired his disciples to devote their lives to the 
 studies into which he introduced them, and filled 
 them with the ardour of devoted proselytes. 
 
 The first feature to which we may direct our atten- 
 tion, distinguishable in every part of his life and work, 
 was his overmastering sense of orderliness and method. 
 This habit of mind became in him a true passion. 
 He is said to have bought books, rather to arrange 
 them systematically than to read them. He observed 
 the details of social etiquette as punctiliously as the 
 characters of minerals, but with one remarkable excep- 
 tion, to which I shall afterwards allude ; and he would 
 deliberate over the arrangement of a dinner with as 
 much gravity as over that of his library or his 
 cabinet. 
 
 We cannot take up any of Werner's writings with- 
 out at once noting this prominent peculiarity of his 
 mind. Every fact, every proposition is definitely 
 
2 1 o Werner 
 
 classified and ticketed, and even when he has little or 
 nothing to say under any particular subdivision, the 
 subdivision is nevertheless placed in its due niche all 
 the same. 
 
 This methodical habit proved of the greatest service 
 to the cause of mineralogy. When Werner entered 
 upon his mineralogical studies, the science of minerals 
 was an extraordinary chaos of detached observations 
 and unconnected pieces of knowledge. But his very 
 first essay began to put it into order, and by degrees 
 he introduced into it a definite methodical treatment, 
 doing for it very much what Linnaeus had done some 
 years before for botany. Like that great naturalist, he 
 had to invent a language to express with precision the 
 characters which he wished to denote, so that mineralo- 
 gists everywhere could recognise them. For this 
 purpose he employed his mother tongue, and devised 
 a terminology which, though artificial and cumbrous, 
 was undoubtedly of great service for a time. Uncouth 
 in German, it became almost barbarous when translated 
 into other languages. What would the modern Eng- 
 lish-speaking student think of a teacher who taught 
 him, as definite characters, that a mineral could be 
 distinguished as " hard, or semi-hard," " soft or very 
 soft," as " very cold, cold, pretty cold, or rather cold," 
 as " fortification-wise bent," as " indeterminate curved 
 lamellar," as " common angulo-granular," or as " not 
 particularly difficultly frangible " ? l 
 
 Werner arranged the external characters of minerals 
 in so methodical a way, that they could readily be 
 
 1 These terms are all taken from the Wernerian system as ex- 
 pounded in English by Werner's pupil, Jameson (note on next page). 
 
His Geognosy 211 
 
 applied in the practical determination of species. Yet 
 strangely enough he neglected the most important of 
 them all that of crystalline form. From the in- 
 dividual minerals, he proceeded to the consideration 
 of their distribution, and the character and origin of 
 the different rocks in v/hich they occur. To this 
 branch of inquiry he gave the name of geognosy, 
 or knowledge of the earth, and he defined it as the 
 science which reveals to us in methodical order the 
 terrestrial globe as a whole, and more particularly the 
 layers of mineral matter whereof it consists, informing 
 us of the position and relations of these layers to each 
 other, and enabling us to form some idea of their 
 origin. The term geology had not yet come into use, 
 nor would either Werner or any of his followers have 
 adopted it as a synonym for the " geognosy " of the 
 Freiberg school. They prided themselves on their 
 close adherence to fact as opposed to theory. One 
 of them, with pointed reference to the writings of 
 Hutton and Playfair, which had appeared shortly 
 before, wrote : " We should form a very false con- 
 ception of the Wernerian geognosy were we to believe 
 it to have any resemblance to those monstrosities known 
 under the name of Theories of the Earth. . . . Armed 
 with all the facts and inferences contained in these 
 visionary fabrics, what account would we be able to 
 give of the mineralogy of a country, if required of 
 us, or of the general relations of the great masses of 
 which the globe is composed ? " l The geognosts 
 
 1 Jameson, "Elements of Geognosy," forming vol. iii. of his 
 System of Mineralogy, p. 4.2. The italics in this quotation are in 
 the original. 
 
2 1 2 Werner 
 
 boasted of the minuteness and precision of their 
 master's system, and contrasted the positive results 
 to which it led with what they regarded as the vague 
 conclusions and unsupported or idle speculations of 
 other writers. Werner arranged the crust of the 
 earth into a series of "formations", which he labelled 
 and described with the same precision that he applied 
 to the minerals in his cabinet. He taught that these 
 formations were to be recognised all over the world, 
 in the same order and with the same characters. The 
 students whom he sent forth naturally believed that 
 they carried with them, in this sequence, the key 
 that would unlock the geological structure of every 
 country. 
 
 But never in the history of science did a stranger 
 hallucination arise than that of Werner and his school, 
 when they supposed themselves to discard theory and 
 build on a foundation of accurately-ascertained fact. 
 Never was a system devised in which theory was 
 more rampant ; theory, too, unsupported by observa- 
 tion, and, as we now know, utterly erroneous. From 
 beginning to end of Werner's method and its applica- 
 cations, assumptions were made for which there was 
 no ground, and these assumptions were treated as 
 demonstrable facts. The very point to be proved 
 was taken for granted, and the geognosts, who boasted 
 of their avoidance of speculation, were in reality among 
 the most hopelessly speculative of all the generations 
 that had tried to solve the problems of the theory of 
 the earth. 
 
 Werner's first sketch of his plan of the structure 
 of the earth's crust and the succession of the rocks 
 
His Universal Formations 213 
 
 that compose it appeared as a thin quarto of only 28 
 pages, published at Dresden in the year lySy. 1 It 
 was descriptive rather than theoretical, and was marked 
 by all its author's precision and orderliness of state- 
 ment. It contained the essence of his system in its 
 simplest form. In later years, as we shall see, further 
 experience compelled him to enlarge and modify the 
 system, but without changing the fundamental con- 
 ceptions on which it was founded. The modifications, 
 however, were not embodied by Werner in any later 
 edition of his work. They were given by him from 
 time to time in his lectures, and gradually became 
 known from the writings of his students. One of the 
 most devoted and distinguished of these followers was 
 Robert Jameson, who afterwards became Professor of 
 Natural History in the University of Edinburgh. He 
 was mainly instrumental in introducing the Wernerian 
 doctrines into Britain, and continued for a number of 
 years to be their most ardent supporter. In many 
 respects the fullest accounts of Werner's views are 
 to be found in the various works of the Edinburgh 
 Professor, and I shall cite some further passages from 
 them in the present chapter. 
 
 One of the fundamental postulates of the Wernerian 
 doctrines was the existence of what were termed uni- 
 versal formations. When he elaborated his system, 
 Werner had never been out of Saxony and the im- 
 mediately adjacent regions. His practical knowledge 
 of the earth was, therefore, confined to what he could 
 
 1 Kurze Klassification und Beschreibung der verschiedenen Gebirgsarten, 
 von A. G. Werner, Bergakademie Inspector, und Lehrer der Berg- 
 baukunst und Mineralogie zu Freiberg. Dresden, 1787. 
 
2 1 4 Werner 
 
 see there, and so little was then known of the geo- 
 logical structure of the globe as a whole, that he 
 could not add much to his acquaintance with the 
 subject by reading what had been observed by others, 
 though there can be little doubt that he stood 
 greatly indebted to Lehmann and Fiichsel. With this 
 slender stock of acquirement, he adopted the old idea 
 that the whole globe had once been surrounded with 
 an ocean of water, at least as deep as the mountains 
 are high, and he believed that from this ocean 
 there were deposited by chemical precipitation the 
 solid rocks which now form most of the dry land. 
 He taught that these original formations were uni- 
 versal, extending round the whole globe, though not 
 without interruption, and that they followed each 
 other in a certain order. He affirmed that the first- 
 formed rocks were entirely of chemical origin, and 
 he called them Primitive, including in them granite, 
 which was the oldest, gneiss, mica-slate, clay-slate, 
 serpentine, basalt, porphyry, and concluding with 
 syenite as the youngest. Succeeding these came what 
 he afterwards separated as the Transition Rocks, 
 consisting chiefly of chemical productions (greywacke, 
 greywacke-slate and limestone), but comprising the 
 earliest mechanical depositions, and indicating the 
 gradual lowering of the level of the universal ocean. 
 Still newer, and occupying, on the whole, lower posi- 
 tions, marking the continued retirement of the waters, 
 were the Floetz Rocks, composed partly of chemical, 
 but chiefly of mechanical sediments, and including 
 sandstone, limestone, gypsum, rock-salt, coal, basalt, 
 obsidian, porphyry, and other rocks. Latest of all 
 
His theoretical conceptions 215 
 
 came the Alluvial series, consisting of recent loams, 
 clays, sands, gravels, sinters, and peat. 
 
 This system was not put forward tentatively as 
 a suggestion towards a better comprehension of the 
 history of the earth. It was announced dogmatically 
 as a body of ascertained truth, about which there could 
 be no further doubt or dispute. Let me quote by 
 way of illustration a few sentences from Werner's 
 'Theory of Veins, where he definitely expresses his 
 opinions on these matters. " In recapitulating the 
 state of our present knowledge," he observes, " it is 
 obvious that we know with certainty that the floetz 
 and primitive mountains have been produced by a 
 series of precipitations and depositions formed in suc- 
 cession from water which covered the globe. We 
 are also certain that the fossils which constitute the 
 beds and strata of mountains were dissolved in this 
 universal water and were precipitated from it ; conse- 
 quently the metals and minerals found in primitive 
 rocks, and in the beds of floetz mountains, were also 
 contained in this universal solvent, and were formed 
 from it by precipitation. We are still further certain 
 that at different periods, different fossils have been 
 formed from it, at one time earthy, at another metallic 
 minerals, at a third time some other fossils. We 
 know, too, from the position of these fossils, one 
 above another, to determine with the utmost precision 
 which are the oldest, and which the newest precipitates. 
 We are also convinced that the solid mass of our globe 
 has been produced by a series of precipitations formed 
 in succession (in the humid way) ; that the pressure 
 of the materials, thus accumulated, was not the same 
 
2 1 6 IVerner 
 
 throughout the whole ; and that this difference of 
 pressure and several other concurring causes have 
 produced rents in the substance of the earth, chiefly 
 in the most elevated parts of its surface. We are 
 also persuaded that the precipitates taking place from 
 the universal water must have entered into the open 
 fissures which the water covered. We know, more- 
 over, for certain, that veins bear all the marks of 
 fissures formed at different times ; and, by the causes 
 which have been assigned for their formation, that 
 the mass of veins is absolutely of the same nature as 
 the beds and strata of mountains, and that the nature 
 of the masses differs only according to the locality of 
 the cavity where they occur. In fact, the solution 
 contained in its great reservoir (that excavation which 
 held the universal water) was necessarily subjected to 
 a variety of motion, whilst that part of it which was 
 confined to the fissures was undisturbed, and deposited 
 in a state of tranquillity its precipitate." 1 
 
 It would be difficult to cite from any other modern 
 scientific treatise a series of consecutive sentences 
 containing a larger number of dogmatic assertions, of 
 which almost every one is contradicted by the most 
 elementary facts of observation. The habit of confi- 
 dent affirmation seems to have blinded Werner to 
 the palpable absurdity of some of his statements. 
 When, for example, he speaks of the great reservoir 
 or excavation which held the universal water, what 
 idea could have been present to his mind ? If the 
 primeval ocean, as he asserted, surrounded the whole 
 
 1 Neue Theorle von der Entstehung der G'dngen, chap. vii. 68 (1791). 
 English translation by Anderson, p. no (1809). 
 
His Theory of a Universal Ocean 217 
 
 globe, and was as deep as the mountains are high, 
 where was the excavation ? As an acute writer in the 
 Edinburgh Review pointed out, the excavation spoken 
 of by Werner " can mean nothing else than the 
 convexity of the solid nucleus round which the 
 universal water was diffused. To call this convexity 
 an excavation, is to use such a freedom with language 
 as can only be accounted for by the perplexity in 
 which every man, of whatever talents, must find him- 
 self involved when he attempts to describe a whole, 
 of which the parts are inconsistent with one another." 1 
 The theory of a primeval universal ocean that over- 
 topped the mountains, which formed the basis of 
 Werner's teaching, led in every direction to such 
 manifest contradictions and absurdities, that we need 
 a little patience and some imagination to picture to 
 ourselves how it could have been received and fervently 
 believed in by men of intelligence, to whom the facts 
 of the earth's structure were not wholly unknown. 
 It was claimed for Werner that the doctrine of a 
 universal and gradually subsiding ocean, though it 
 had been taught long before his time, was first demon- 
 strated by him to be true, (i) because he found the 
 older strata occupying the highest eminences, and the 
 younger coming in at successively lower levels, down 
 to the modern alluvia of the plains and the sea-shore, 2 
 and (2) because the primitive and loftiest rocks are 
 entirely formed of chemical precipitations, those of 
 
 1 Edtn. Review, xviii. p. 90 (1811). 
 
 2 But as has been shown in a previous chapter, this idea had been 
 clearly enunciated long before by Buffbn and was recognized by 
 Werner's German predecessors. 
 
2 1 8 IVerner 
 
 mechanical origin not appearing until a much later 
 period, and becoming increasingly abundant down to 
 the present time, when they constitute almost all the 
 deposits that are now taking place. 1 
 
 One of the most obvious questions that would arise, 
 we might suppose, in the mind of any student of 
 ordinary capacity to whom the theory was propounded, 
 would be how did the deep primitive ocean disappear. 
 Steno, Leibnitz, and other older writers had conjectured 
 that the waters found their way into vast caverns in 
 the earth's interior. Such a conjecture, however, was 
 not suited to the taste of the true Wernerian, who 
 would allow no speculation, but took his stand on a 
 basis of ascertained fact. Well, we may be curious to 
 know how he disposed of the difficulty. Yet we 
 shall search in vain through Wernerian literature for 
 any serious grappling with this obvious, and one 
 would have thought formidable, objection to the 
 doctrine. Werner himself appears to have inclined 
 to the belief that the waters vanished into space. He 
 thought it possible that " one of the celestial bodies 
 which sometimes approach near to the earth may 
 have been able to withdraw a portion of our atmos- 
 phere and of our ocean."' But if once the waters 
 were abstracted, how were they to be brought back 
 again, so as to cover all the hills on which his highest 
 Floetz formations were deposited ? 
 
 1 Jameson's Geognosy, p. 78. Werner's followers, from the promi- 
 nence they gave to the sea in their geognosy, were styled Neptunists, 
 while those of Hutton, who dwelt on the potency of the earth's 
 internal fire, were dubbed Plutonists or Vulcanists. 
 
 2 See D'Aubuisson's Geognosie, i. p. 414 (1819). 
 
Diminution of his Universal Ocean 219 
 
 The most famous of the English followers of 
 Werner, Jameson, honestly asked the question, "What 
 has become of the immense volume of water that once 
 covered and stood so high over the whole earth ? " 
 His answer may be cited as thoroughly characteristic 
 of the mental attitude of a staunch Wernerian. " Al- 
 though," he says, " we cannot give any very satis- 
 factory answer to this question, it is evident that the 
 theory of the diminution of the water remains equally 
 probable. We may be fully convinced of its truth, 
 and are so, although we may not be able to explain 
 it. To know from observation that a great pheno- 
 menon took place, is a very different thing from 
 ascertaining how it happened." 1 I do not suppose that 
 in the whole literature of science a better illustration 
 could be found of the advice " When you meet with 
 an insuperable difficulty, look it steadfastly in the face 
 and pass on." 
 
 One might have thought that having disposed of 
 the universal ocean, even in this rather peremptory 
 fashion, the Wernerians would have been in no hurry 
 to call it back again, and set the same stupendous 
 and inexplicable machinery once more going. But 
 the exigencies of their theory left them no choice. 
 Having determined, as an incontrovertible fact, that 
 certain rocks had been deposited as chemical precipitates 
 in a definite order from a universal ocean, when these 
 philosophers, as their knowledge of Nature increased, 
 found that some of these so-called precipitates occurred 
 out of their due sequence and at much higher altitudes 
 than had been supposed, they were compelled to bring 
 1 Jameson, op. at. p. 82. 
 
220 Werner 
 
 back the universal ocean, and make it rise high over 
 hills from which it had already receded. Not only 
 had they to call up the vasty deep, but they had to 
 endow it with rapid and even tumultuous movement, 
 as it swept upwards over forest-clothed lands. Having 
 raised it as high as their so-called Floetz formations 
 extended, and having allowed its waters to settle and 
 deposit precipitates of basalt and greenstone, they had 
 to hurry it away again to the unknown regions where 
 it still remains. This, forsooth, was the system that 
 discarded hypothesis, and rested proudly on an irre- 
 fragable foundation of demonstrable fact. 
 
 In another notable respect the crudeness of the 
 Wernerian sytem and its disregard of the most familiar 
 facts in nature are shown by its classification of so 
 many diverse kinds of rocks as chemical precipitates 
 from a hypothetical universal ocean. Chemistry was 
 then sufficiently far advanced to prove the absurdity 
 of this dogma. Even if the ocean had been a mass 
 of boiling water, it could not have held all these rocks 
 in solution, and have deposited them as successive 
 precipitates. But the Wernerian geognosts scouted 
 the idea that the globe and its outer envelopes, ever 
 had a high temperature. They seem never to have 
 tried to reason out the chemical reactions involved 
 in their theory of solution and precipitation, nor to 
 have formed any conception of the causes which could 
 have led to the successive deposition of the various 
 precipitates. That the ocean could not have been a 
 strong solution of mineral substances when the so- 
 called chemical precipitates of the Transition Rocks 
 were deposited, but must have had a composition 
 
His explanation of Basalt 221 
 
 not greatly dissimilar to what it possesses now might 
 have been suggested to these theorists by the occur- 
 rence of the abundant remains of animal life in many 
 of the rocks a fact of which they ultimately became 
 well aware. 
 
 A further singular characteristic of the Wernerian 
 school was the position it took up with regard to the 
 evidence for disturbances of the earth's crust, and for 
 the universality and potency of what is now termed 
 igneous action. A hundred years before Werner's 
 time Steno had pointed to the inclined and broken 
 strata of Northern Italy as evidence of dislocation of 
 the crust. The Italian observers, and especially Moro, 
 familiar with the phenomena of earthquakes and vol- 
 canoes, had been impressed by the manifest proofs 
 of the potency of the internal energy of the earth 
 upon its outer form. But these early adumbrations 
 of the truth were all brushed aside by the oracle of 
 Freiberg. I have tried to imagine the current of 
 thought by which Werner was led to this crowning 
 absurdity of his system, and I think we may trace it 
 in the history of his relation to the basalt hills of 
 Saxony. The question is of some interest, not only 
 as a curious piece of human psychology, but because 
 it was on this very point of the origin of basalt that 
 the Wernerian ship finally struck and foundered. 
 
 The year after his appointment as teacher of 
 mineralogy, Werner visited the famous Stolpen, one 
 of the most picturesque castle-crowned basalt hills 
 of Saxony, to which I have already referred in con- 
 nection with Agricola's revival of the old word 
 " basalt." He had probably by this time begun to 
 
222 Werner 
 
 form in his mind a more or less definite picture 
 of chemical precipitation from aqueous solution, as 
 applied to the history of rock-masses. But be this 
 as it may, he was aware that basalt, by not a few 
 observers before his time, had been claimed as a 
 rock of volcanic origin. How far he had then 
 made up his mind as to the formation of that rock 
 must remain in doubt. But he tells us himself that 
 at the Stolpen he " found not a trace of volcanic 
 action, nor the smallest proof of volcanic origin. So 
 I ventured publicly to assert and prove that all basalts 
 could certainly not be of volcanic origin, and that to 
 these non-volcanic rocks the Stolpen mass undoubtedly 
 belongs. Though at first I met with much opposi- 
 tion, yet soon several geognosts came over to my 
 views. These views gained special importance from 
 the observations which I made in 1777 on the old 
 subterranean fire in the coal-field that lies around 
 the hills of basalt and porphyry-slate in the middle of 
 Bohemia, and the consequent pseudo-volcanic hills that 
 have arisen there. After further more matured re- 
 search and consideration, I hold that no basalt is 
 volcanic, but that all these rocks, as well as the other 
 Primitive and Floetz rocks, are of aqueous origin." l 
 
 1 Kurze Klassifcation und Beschreibung der Verschledenen Gebirgsarten, 
 1787, p. 25. Later in the same year (1787) he visited a little 
 eminence near Scheibenberg in the Erzgebirge, and found there 
 a cake of basalt lying on clay and sand, and thought he could trace 
 these materials passing into each other. Whereupon he announced 
 as a " new discovery " that all basalt is of aqueous origin, and 
 constitutes, with clay, sand and wacke, one single formation which 
 originally extended far and wide over the primitive and floetz 
 rocks, but has in course of time been worn away, leaving only 
 cappings on the hills. Keferstein, Geschlchte der Geognosie, p. 69. 
 
The Basalt Controversy 223 
 
 Thus ten years of reflection had only served to 
 make him more positive in maintaining an opinion 
 which the most ordinary observation in his own 
 Saxony ought to have enabled him to disprove and 
 reject. He had not only asserted that basalt is a 
 chemical precipitate, but had placed it among his 
 primitive rocks. 
 
 When we remember the long and patient labours 
 of Desmarest before he announced his conclusions 
 regarding the volcanic origin of basalt, we cannot 
 but wonder at the audacity of Werner in discarding 
 these conclusions without comment, and announcing 
 an entirely opposite opinion, rapidly formed on the 
 slender evidence of one or two isolated patches of 
 basalt. It was not as if he claimed to apply his 
 explanation merely to those few cases which he had 
 himself examined ; he swept all the basalts of the 
 earth's surface into his net. His view had not even 
 the merit of originality, for, as we have seen, Guet- 
 tard, among others, had held the opinion that basalt 
 is of aqueous origin. But, announced as a new dis- 
 covery, with all the authority of the great Freiberg 
 professor, it commanded attention and met with wide 
 acceptance. Even from the time of its promulgation, 
 however, it awakened some opposition, and it became 
 the subject of bitter controversy for fully a generation. 
 Only a month after Werner proclaimed his discovery 
 he was answered by J. K. W. Voigt of Weimar, who 
 maintained the volcanic nature of the very examples 
 cited by the professor. 1 Werner replied, and was 
 
 l Bergmann. Journ. 1788, 1789, 1791, pp. 185, 347, etc. See 
 also Hoffmann's Geschichte der Geognos'r (1838), p. 117. 
 
224 Werner 
 
 again answered, but soon retired from the combat and 
 devoted his energies to strengthen his theory. As an 
 instance of the wide interest taken in the question, 
 I may mention that even at Berne, where there are 
 no basalts, nor any other traces of volcanic action, 
 the Society of Naturalists of that town offered a prize 
 of twenty-five thalers for the best essay in answer to 
 the question, " What is Basalt : Is it volcanic or is 
 it not ? " The successful competitor, after elaborately 
 reviewing all the arguments brought forward by the 
 Vulcanists, pronounced in favour of Werner's views. 1 
 Werner himself made two contributions to the dis- 
 cussion, one giving his theory of volcanoes, 2 and the 
 other his matured views upon basalt. 3 
 
 Volcanoes and volcanic action, if they were regarded 
 as betokening any potent kind of reaction between 
 the interior and the exterior of our planet, were utterly 
 antagonistic to Werner's conception of the structure 
 and history of the earth. In a world which had 
 entirely resulted from the precipitations and depositions 
 of an ocean of water, there was obviously no place for 
 internal fire. In the system which Werner had so 
 laboriously devised, it was imperatively necessary to 
 treat volcanoes as modern and accidental phenomena, 
 which never entered into the process of the formation 
 of the crust of the earth. Accordingly, in his earliest 
 sketch of his classification of rocks, he placed volcanic 
 rocks among the latest of the whole series. And this 
 
 1 J. F. W. Widenmann, Hopfner's Magazin fiir die Erdkunde, iv. 
 (1789), p. 135. 
 
 2 Hopfner's Magazin fur die Erdkunde, iv. (1789), p. 239. 
 9 Bergmdnnisches Journal, 1789, i. p. 252. See also p. 272. 
 
Werner on Volcanoes 225 
 
 view he maintained to the last. That volcanic action 
 had been in progress from the very beginning of 
 geological time, and that it had played an important 
 part in building up the framework of the land in 
 many countries all over the globe, were ideas that 
 seem never to have occurred to him. 
 
 We have seen how old was the notion that vol- 
 canoes, or " burning mountains/' arose from the 
 combustion of subterranean beds of coal. Werner 
 adopted this opinion, which suited his system, and 
 was quite in congenial surroundings there. In 1789, 
 two years after the appearance of his little Kurze 
 Klassification, he definitely announced, in one of the 
 papers above referred to, what he called the " highly 
 probable conjecture that most, if not all, volcanoes 
 arise from the combustion of underground seams of 
 coal." * The coal might be set on fire by spontaneous 
 combustion, and the most vigorous volcanoes would 
 be those starting on the thickest masses of coal. In 
 order to support this belief, it was necessary to furnish 
 evidence of the existence of deposits of coal around 
 volcanoes. And much research and ingenuity were 
 displayed in collecting all the known examples. Not 
 only coal, but every kind of natural inflammable sub- 
 stance was pressed into service, and made to do duty 
 as fuel for the subterranean fires. 
 
 It was also obviously needful to maintain that vol- 
 canoes must be comparatively modern phenomena. 
 We are told that " it was only after the deposition 
 of the immense repositories of inflammable matter 
 in the Floetz-trap that volcanoes could take place ; 
 
 1 See the paper just cited in Hopfner's Magaz. iv. (1789), 240. 
 
 P 
 
226 Werner on Basalt and Lava 
 
 they are therefore to be considered as new occurrences 
 in the history of Nature. The volcanic state appears 
 to be foreign to the earth." x 
 
 The similarity of basalt to many undoubtedly vol- 
 canic rocks had long been noticed, and could not 
 escape the observant eyes of Werner. But he did 
 not therefore infer basalt to be of volcanic origin. 
 He had already established, as one of the indisputable 
 canons of geognosy, that basalt was precipitated from 
 chemical solution in a universal ocean. The way 
 in which he accounted for the resemblance between 
 basalt and lava must be regarded as a signal proof of 
 his ingenuity. He announced that volcanoes not 
 only occur where there are seams of coal, but where 
 these are covered by sheets of basalt and wacke, and 
 that eruptions of lava take place when these overlying 
 rocks are melted by the combustion of the coal. He 
 thus provided himself with a triumphant answer to any 
 objector who felt inclined to question his dictum as to 
 the origin of basalt. If the rock occurred on isolated 
 hill tops, it was a member of the Floetz-trap formation 
 produced by universal chemical precipitation. If it 
 was found in the condition of lava, the original precipi- 
 tate had been fused by the burning of underlying 
 seams of coal. 
 
 With so flexible a theory to defend and apply, it can 
 be understood how the pupils of the Freiberg school 
 scouted the notion that volcanoes were of any real 
 geognostical importance, and how they had a ready 
 
 1 Jameson's Geognosy, p. 96. Werner could not claim even 
 originality for this absurd doctrine, for it had been adopted by 
 Buffon before the Saxon professor was born (ante, p. 93). 
 
Wernerian Volcanic Theory 227 
 
 answer to any opponent, or a prompt explanation 
 of any apparent difficulty in the acceptance of their 
 master's teaching. If any one claimed that basalt was 
 of volcanic origin, he was at once confidently assured 
 that this was an entire mistake, for the great law-giver 
 of Freiberg had pronounced it to be a chemical precipi- 
 tate from water. If he ventured to quote the columnar 
 structure as in favour of his view, he was told that 
 he ought to know that lava never assumed this 
 structure, 1 and that " rocks which have been formed 
 or altered by the action of heat are most distinctly 
 different from those that constitute the great mass 
 of the crust of the globe." 2 If he brought to the 
 unabashed Wernerian a piece of obsidian, and asked 
 whether such a rock should not be admitted to be 
 a volcanic glass, " Nothing of the kind," would have 
 been, in effect, the immediate reply. " It is true that 
 the rock does resemble c completely melted stony sub- 
 stances, and occurs in volcanic countries/ but the 
 notion that it is itself of volcanic origin is quite 
 unfounded, ( because obsidian has never been observed 
 accompanying lava, because it is connected with basalt, 
 and because it contains a considerable portion of water 
 of composition, which is never the case with true 
 volcanic rocks/" 3 If the questioner, still unconvinced, 
 presumed to present a piece of pumice, pointing to its 
 froth-like structure and its presence in volcanic coun- 
 tries as evidence of its former fusion, the answer would 
 have been an equally prompt and decided negative. 
 Let me quote the actual words of a Wernerian in 
 
 1 Jameson, op. cit. p. 58. 2 O/. cit. p. 74. 
 
 3 Op. cit. p. 1 96. 
 
228 Werner on disturbances of earth's crust 
 
 reply. " It was formerly the general opinion that 
 pumice was a volcanic product, because it frequently 
 occurs in countries conjectured to be of igneous forma- 
 tion. It is now ascertained to be an aquatic product, 
 from the following facts : i, It alternates with Nep- 
 tunian rocks, as basalt and porphyry ; 2, it is most 
 distinctly stratified ; 3, it passes into obsidian and 
 pearlstone, and is thus connected with basalt, pitch- 
 stone, etc. ; 4, it contains water of composition, which 
 is never the case with true volcanic rocks ; 5, it has 
 never been observed to flow in streams from the crater 
 or sides of a volcano, and no one ever saw it forming 
 a stream in countries containing extinct volcanoes." 1 
 
 Well might the inquirer retire in despair from such 
 an encounter. In vain would he have sought an 
 explanation of the origin of the vesicular structure of 
 the rock, or have asked how this structure could ever 
 have originated from an aqueous solution. He would 
 probably have been plied with a few more " facts " of 
 equal veracity, and a few more examples of reasoning 
 in a circle. But he would never succeed in extracting 
 an expression of doubt, or an admission that the ipse 
 dimt of the Freiberg professor could for a moment be 
 called in question. 
 
 The same attitude which Werner assumed towards 
 volcanoes was consistently maintained by him in his 
 treatment of the proofs of disturbances in the terrestrial 
 crust. He seems never to have realized that any reser- 
 voir of energy is stored up in the interior of our globe. 
 It was part of his teaching that the spheroidal form of 
 the planet furnished one of the proofs of a primeval 
 1 Jameson, op. cit. p. 196. 
 
IVerner on Mineral Veins 229 
 
 universal ocean. He admitted that the crust had been 
 abundantly cracked, but in these cracks he saw no 
 evidence of any subterranean action. His own state- 
 ment of his views on this subject is sufficiently explicit, 
 and I quote his words : " When the mass of materials 
 of which the rocks were formed by precipitation in the 
 humid way, and which was at first soft and movable, 
 began to sink and dry, fissures must of necessity have 
 been formed, chiefly in those places where the greatest 
 quantity of matter has been heaped up, or where the 
 accumulation of it has formed those elevations which 
 are called mountains." 1 He gave no explanation of 
 the reason why the precipitates of his universal ocean 
 should have gathered more thickly on one part of the 
 bottom than on another. It was enough for himself 
 and his disciples that he was convinced of the fact. 
 
 As all rents in the earth's crust were thus mere 
 superficial phenomena resulting from desiccation and 
 the slipping down of material from the sides of moun- 
 tains, so it was conceived by Werner that, when they 
 were filled up, the mineral matter that was introduced 
 into them could only come from above. He drew no 
 distinction in this respect between what are now called 
 <c mineral veins " and " intrusive veins." Veins of 
 granite, of basalt, of porphyry, of quartz, of galena, or 
 of pyrites were all equally chemical precipitates from an 
 overlying sea. He does not appear to have seen any 
 difficulty in understanding how the desiccation and 
 rupture of the rocks were to take place, if the sea still 
 covered them, or how, if they were exposed to the air 
 and evaporation, he was to raise the level of the ocean 
 1 Theory of Veins, 39. 
 
230 Werner's Classification of Rocks 
 
 again so as to cover them, and fill up their rents with 
 new precipitates. 
 
 Werner's original scheme of classification of the 
 rocks of the earth's crust had at least the merit of 
 clearness and simplicity. Though he borrowed his 
 order of sequence partly from Lehmann and Fiichsel, 
 he worked it into a scheme of his own regarding the 
 origin of the rocks and their successive production 
 from a universal ocean. Tracing in the arrangement 
 of the rocks of the earth's crust the history of an 
 original oceanic envelope, finding in the masses of 
 granite, gneiss, and mica-schist the earliest precipita- 
 tions from that ocean, and recognising the successive 
 alterations in the constitution of the water as witnessed 
 by the series of geological formations, Werner launched 
 upon the world a bold conception which might well 
 fascinate many a listener to whom the laws of chemistry 
 and physics, even as then understood, were but little 
 known. Unfortunately the conception was based en- 
 tirely on the imagination, and had no real foundation 
 in observation or experiment. 
 
 Werner adopted the leading ideas of his system in 
 an early part of his career when his personal experience 
 was extremely limited. And having once adopted 
 them, he maintained them to the last. His methodical 
 mind demanded some hypothesis that would allow him 
 to group, in definite and genetic connection, all the 
 facts then known regarding the structure of the earth's 
 crust. His first sketch of a classification of rocks 
 shows by its meagreness how slender at that time 
 was his practical acquaintance with rocks in the field. 
 The whole of the Primitive formations enumerated 
 
chronological method 231 
 
 by him are only twelve in number, and some of these 
 were confessedly rare. As years went on, he inter- 
 calated new varieties, introduced the division of 
 Transition rocks, and was compelled to reduplicate 
 some of his primitive formations by having to find 
 places also for them among the Floetz series. 
 
 Yet with all these shiftings to and fro, the apparent 
 symmetry and conspicuous method of the system were 
 retained to the end. No Saxon mine could have had 
 its successive levels more regularly planned and driven, 
 than the crust of the earth was parcelled out among 
 the various Wernerian universal formations. Each of 
 these had its definite chronological place. When you 
 stood on granite, you knew you were at the base 
 and root of all things mundane. When you looked 
 on a hill of Floetz-trap you saw before you a relic 
 of one of the last acts of precipitation of the ancient 
 universal ocean. 
 
 But Nature has not arranged her materials with the 
 artificial and doctrinaire precision of a mineralogical 
 cabinet. Werner's system might temporarily suffice 
 for the little part of the little kingdom of Saxony 
 which, when he promulgated his views, he had im- 
 perfectly explored. But as his experience widened 
 and new facts accumulated, the modifications to which 
 I have referred were so serious that they might well 
 make the author of the system pause, and raise in his 
 mind some doubts whether the fundamental conception 
 on which the system was based could possibly be true. 1 
 
 1 D'Aubuisson, a loyal and favoured pupil of the Saxon Professor, 
 remarks that "Werner has continued from year to year to modify, 
 and even to recast, some parts of his doctrine, while his disciples, 
 
232 Artificiality of JVerne^s system 
 
 It was eventually found, for instance, that some granite 
 overlies instead of underlying the slates of the Primitive 
 series ; that some greenstones, instead of occurring 
 among the Primitive rocks, lie in the Floetz division ; 
 that there are ever so many horizons for porphyry, 
 which was at first believed to be entirely Primitive. 
 These contradictions were surmounted by affixing such 
 adjectives as " oldest " or " newest " to the several 
 appearances of the same rock, or by numbering them 
 according to their various horizons. Thus there were 
 oldest and newest granites, oldest and newer serpen- 
 tine, and first, second, and third porphyry formations. 
 
 This patching up of the system may have saved it 
 in appearance, but a moment's reflection will show us 
 that it was fatal to Werner's fundamental doctrine of 
 a series of successive chemical precipitates from a uni- 
 versal ocean, which by the deposition of these precipi- 
 tates was gradually altering its constitution. The 
 modifications rendered necessary by fresh discovery 
 proved that the supposed definite sequence did not 
 exist. In fact, as was well said by a critic at the 
 time, they were mere u subterfuges by which the 
 force of facts was evaded." 1 They were devised for 
 the purpose of bolstering up a system which was 
 entirely artificial, and to the erroneousness of which 
 new facts were continually bearing witness. 
 
 It was claimed for Werner that he first established 
 the doctrine of geological succession in the earth's 
 
 following his teaching, in proportion as their observations have 
 multiplied, have added, and are continually adding new improve- 
 ments to his system." Traite de Geognosle (1819), preface, p. xvi. 
 ^Edinburgh Review, vol. xviii. (1811), p. 95. 
 
Werners lectures 233 
 
 crust. We have seen that the idea was already 
 supplied to him by Lehmann and Fttchsel, and it is 
 now evident that, by working into it his notion of 
 universal aqueous precipitates, he introduced an element 
 of hypothesis which threw back for some years the 
 progress of sound geology. What was true in the 
 doctrine was borrowed from his predecessors, what 
 was his own consisted largely of unwarranted assump- 
 tion. He undoubtedly did enormous service by his 
 precise definitions and descriptions of rocks, and by 
 dwelling on the fact that there was an observable 
 order of succession among them, even though he 
 mistook this order in some important particulars, and 
 entirely misinterpreted its meaning and history. The 
 full significance of geological succession was not under- 
 stood until it was worked out independently in Eng- 
 land and France by a rigid collection of facts and on 
 a palaeontological basis, as I shall describe in a later 
 chapter. 
 
 Werner's writings are so few and slight that his 
 disciples and admirers continually expressed their 
 sorrow that he would leave so little behind him 
 save his world-wide fame. His natural dislike of the 
 pen increased with his years. He would discourse 
 eloquently on many subjects, but could never bring 
 himself to write fully on any one. Usually when he 
 went to lecture he would retire for a quarter of an 
 hour to arrange his ideas, and when he appeared before 
 his audience he brought with him only some scraps of 
 paper, with a few words scribbled on them. He never 
 wrote a single lecture. If this abstinence from the 
 use of the pen saved him from scientific controversy 
 
234 Werner's aversion to writing 
 
 it did not secure him undisturbed repose. With all 
 his efforts after the placid life of a philosopher, there 
 was one subject that not unnaturally stirred his wrath 
 the unwarranted publication, or at least circulation of 
 his lectures and theories. As he did not publish them 
 himself, and as there was a widespread desire to become 
 acquainted with them, manuscript copies of notes of his 
 lectures were widely circulated, as a kind of mercan- 
 tile speculation. This was bad enough, but he heard 
 of an intention to print and publish them. So he 
 took an opportunity of cautioning the world that, 
 while willing to shut his eyes on the past, he could 
 not tolerate any such conduct in future, that he was 
 himself engaged in revising his works on the several 
 branches of science he professed, and that they would 
 " forthwith appear one after another, enriched by his 
 latest observations and discoveries." l But the revi- 
 sion was never made, and the publications never 
 appeared. 
 
 Werner's repugnance to writing in any form increased 
 with his years. By degrees he ceased to write letters, 
 even when the dearest friend begged for a reply, and 
 at last, to save himself from the reproach of this 
 neglect, he allowed the letters which he received to 
 remain unopened. Cuvier tells how once an author, 
 desiring to consult some of the learned men of the day 
 concerning a work which he proposed to publish, circu- 
 lated his voluminous manuscript among them. The 
 precious parcel disappeared in the circuit. After end- 
 less seeking, it was disinterred in Werner's room from 
 underneath some hundreds of others. He never 
 1 New Theory of the Formation of Veins , 1791, preface. 
 
Characteristics of Werner 235 
 
 answered the Academy of Sciences of Paris when it 
 conferred on him the very high distinction of electing 
 him one of its eight foreign associates, and he might 
 never have heard of the affair had he not come across 
 the mention of it in some almanack. " But," says 
 Cuvier, " we forgave him when we heard that about 
 the same time a messenger sent express by his sister 
 from Dresden had been kept waiting, at the professor's 
 expense, for two months for a mere signature to some 
 pressing family document." 
 
 Save for the occasional irritation caused by rumours 
 of the unwarranted reproduction of his lectures, Wer- 
 ner's life appears to have passed quietly in the midst of 
 the work which he loved and the pupils and friends 
 who looked up to him with veneration and affection. 
 His health was never robust, and the effort of lecturing 
 proved sometimes a great strain upon his energy. 
 After a discourse in which he would pour forth his 
 ideas with the full flow of his exuberance, the bodily 
 and mental effort would be so great that he would 
 have to change his clothes even to his inner raiment. 
 He tried to preserve both body and mind in an equable 
 frame. Among his little foibles was the care he took 
 never to expose himself to a draught. He kept him- 
 self out of controversy, and eventually refrained even 
 from reading the journals, and from knowing what was 
 said in the outer world about himself and his opinions. 
 In this tranquil life he might perhaps have prolonged 
 his days, had not his feelings been deeply stirred by the 
 misfortunes which, during the Napoleonic wars, had 
 befallen Saxony, his adopted home. He took these 
 trials so much to heart that they led to a series of 
 
236 Characteristics of IVerner 
 
 internal complications, from which he died at Dresden, 
 in the arms of his sister, on 3Oth June 1817, in the 
 sixty-eighth year of his age. 
 
 Whether the regrets loudly expressed by his con- 
 temporaries that Werner published so little were justi- 
 fied, may perhaps be open to doubt. If his fame had 
 to rest on his written works, or even on his teaching as 
 expounded by his pupils, it could never have grown so 
 great, nor, judging from what we know of his views in 
 maturer life, can we suppose that any account of them 
 by himself would really have added to his reputation, 
 or have contributed materially to the advancement of 
 science. It was not his writings, nor even his opinions 
 and theories in themselves, that gave him his unques- 
 tioned authority among the geologists of his time. 
 His influence and fame sprang mainly from the 
 personality of the man. His unwearied enthusiasm 
 and eager zeal in the furtherance of his favourite 
 studies, his kindness and helpfulness, his wide range 
 of knowledge, and the vivacity, perspicuity, and 
 eloquence with which he communicated it, his abso- 
 lute confidence in the solidity of his theoretical 
 doctrines these were the sources of his power rather 
 than the originality and importance of his own contri- 
 butions to geology. His followers, indeed, captivated 
 by the precision of his system and its apparent applica- 
 bility in any and every country, claimed for him the 
 highest place in the ranks of those who had studied the 
 history of the earth. But the exaggeration of their 
 claim was amply shown by the rapidity with which 
 the Wernerian doctrines began to fall into disrepute 
 even before the death of their author. 
 
CHAPTER VIII 
 
 THE Wernerian School of Geology, Its great initial influence and 
 subsequent decline. Effect of the controversy about the origin 
 of Basalt upon this School. Early history of Volcanic Geology. 
 History of opinion regarding Earthquakes. 
 
 IN tracing the influence of Werner's teaching upon the 
 progress of geological inquiry, we must begin by the 
 full and frank acknowledgment that when all objec- 
 tions and qualifications have been made regarding his 
 theoretical opinions, the momentous fact remains that 
 by his personal example and contagious enthusiasm 
 he rendered a vast service to the science. He 
 awakened a far more widespread interest in the 
 ancient history of the earth than had ever before 
 existed, and even where his pupils found reason 
 eventually to abandon many of the doctrines which 
 he had taught them, they still retained their devotion 
 to the studies for which he had kindled in them so 
 ardent a zeal. " It was to his irresistible influence," 
 as Cuvier has well remarked, " that the world owes 
 those authors who have treated so fully of minerals, 
 and those indefatigable observers who have so fully 
 explored the globe. The Karstens and the Wiede- 
 manns in the cabinet, the Humboldts, the Von Buchs, 
 
238 Influence of Werner on Petrography 
 
 the D'Aubuissons, the Hermanns, the Freieslebens, 
 at the summit of the Cordilleras, in the midst of 
 the flames of Vesuvius and of Etna, in the deserts 
 of Siberia, in the depths of the mines of Saxony, of 
 Hungary, of Mexico, of Potosi, have been borne on- 
 ward by the spirit of their master ; they have brought 
 back to him the honour gained by their labours ; and 
 we may say of him, what was never truthfully said 
 before, save of Linnaeus, that Nature everywhere 
 found herself interrogated in his name." 
 
 Besides this general impetus to the pursuit of 
 geology, Werner left on the science of his time and 
 country that bias towards the mineralogical and petro- 
 graphical side which has ever since so honourably 
 distinguished German geological investigation, and 
 which in our own day has culminated in the master- 
 pieces of Roth, Groth, Zirkel, Rosenbusch, and many 
 other notable writers. Again, his constant advocacy 
 of the doctrine of geological succession kept the 
 interest and importance of the problem before the 
 world, and helped to prepare the way for the great 
 advances which have since been made in that depart- 
 ment of the science. But his theoretical views on 
 this subject, and the comparative neglect of organic 
 remains in his system, tended to retard in his own 
 country the fuller development of stratigraphy, which 
 was making even during his lifetime such rapid 
 strides in England and France. 
 
 As it was the exigencies of Saxon mining industry 
 that started the Mining School of Freiberg, so the 
 teaching there had necessarily constant reference to 
 the underground operations of the district. Much of 
 
Characteristics of Werner's Teaching 239 
 
 Werner's practical acquaintance with the relations and 
 structure of rock-masses was derived from what he 
 learnt at the mines. It was only natural, therefore, 
 that he should have inculcated upon his pupils the vast 
 importance of subterranean exploration in unravelling 
 the structure of the earth. The devout Wernerian 
 put mines before mountains as a field for geological 
 investigation. 1 Indeed the whole system of the Frei- 
 berg school, with its limited knowledge, its partial view 
 of things, its dogmatism and its bondage to precon- 
 ceived theory, is suggestive rather of the dim lamplight 
 and confined outlook of a mine than of constant and 
 unfettered contact with the fresh and open face of 
 Nature. 
 
 These characteristics of Werner's teaching were 
 keenly felt by some of the more clear-sighted of his 
 contemporaries, who, though they recognised his 
 genius and the vast services he had rendered to 
 mineralogy by solid achievement, as well as by the 
 enthusiasm he had excited in many hundreds of pupils, 
 yet felt that in regard to geological progress his influ- 
 ence had become retrogressive and obstructive. This 
 judgment was forcibly expressed in the article which 
 appeared in the Edinburgh Review in the year 1 8 1 1 
 from which some citations have been given in the fore- 
 going pages. I have reason to believe that this article 
 was from the pen of Dr. W. H. Fitton, who after- 
 wards became one of the leaders of English geology. 
 A few sentences from it may here be quoted. 
 
 "The Wernerian school obstructs the progress of 
 discovery. The manner in which it does so is plain. 
 1 See, for example, Jameson, op. clt. p. 43. 
 
240 The IVernerian Geognosy 
 
 By supposing the order already fixed and determined 
 when it is really not, further inquiry is prevented, and 
 propositions are taken for granted on the strength of a 
 theoretical principle, that require to be ascertained by 
 actual observation. It has happened to the Wernerian 
 system, as it has to many other improvements ; they 
 were at first inventions of great utility ; but being 
 carried beyond the point to which truth and matter 
 of fact could bear them out, they have become obstruc- 
 tions to all further advancement, and have ended with 
 retarding the progress which they began with accelerat- 
 ing. This is so much the case in the instance before 
 us, that when a Wernerian geognost, at present, enters 
 on the examination of a country, he is chiefly employed 
 in placing the phenomena he observes in the situations 
 which his master has assigned to them in his plan of 
 the mineral kingdom. It is not so much to describe 
 the strata as they are, and to compare them with rocks 
 of the same character in other countries, as to decide 
 whether they belong to this or that series of deposi- 
 tions, supposed once to have taken place over the 
 whole earth ; whether, for example, they be of the 
 Independent Coal or the Newest Floetz-trap forma- 
 tion, or such like. Thus it is to ascertain their place in 
 an ideal world, or in that list of successive formations 
 which have nothing but the most hypothetical exist- 
 ence : it is to this object, unfortunately for true 
 science, that the business of mineralogical observation 
 has of late been reduced." x 
 
 So long as the great master at Freiberg lived, the 
 loyalty of his attached pupils naturally kept them 
 ln. Review, vol. xviii. (1811), art. 3, pp. 96, 97. 
 
J. F. D'Aubuisson 241 
 
 from openly rejecting his doctrines, even when they 
 could no longer accept them. His death in 1817 
 was felt by many of them to bring a relief from the 
 despotism which he had so long exercised. 1 And 
 from that time his system declined in favour even in 
 Germany. 
 
 It was one of the most singular episodes in the his- 
 tory of geological science that the first serious check 
 to the triumphal march of Wernerianism through 
 Europe came from two of Werner's most distin- 
 guished pupils, D'Aubuisson and Von Buch, and that 
 their first opposition to their master's teaching was 
 inspired by that very volcanic tract in Central France 
 to which Desmarest had so long before appealed in 
 vain. Let us see how, in this instance, the whirligig 
 of time brought in his revenges. 
 
 Jean Francois D'Aubuisson de Voisins (1769-1819) 
 was born in the south of France on i6th April, 1769. 
 After receiving his early education in his own country, 
 he spent some years as a diligent student at the Mining 
 School of Freiberg. For four consecutive years, he 
 tells us, he was in the most favourable circumstances 
 for mastering the Wernerian doctrines, inasmuch as 
 the illustrious teacher honoured him with particular 
 attention, and in the course of many conversations 
 unfolded to him the principles of his science, and 
 traced for him the path that would lead him to the 
 
 1 One of Jameson's ablest pupils, Ami Boue, trained in the Wer- 
 nerian faith, confessed, but with evident reluctance, and " as a truth 
 which others may be unwilling to make public," that Werner's death 
 had greatly contributed to the progress of geology in Germany. 
 Journ. Phys. xciv. (1822), p. 298. 
 
 Q 
 
242 D'Aubuisson on Basalt 
 
 establishment of a true geognosy. 1 While still pur- 
 suing his studies in Saxony, D'Aubuisson took up 
 the question of the basalts of that kingdom, travelled 
 over all their scattered hills, and at last wrote a treatise 
 upon them, which appeared in Paris in 1803. In this 
 little volume of 170 pages the Wernerian doctrine as 
 to the origin of basalt is not only accepted but treated 
 as if it were incontestable. In one passage, indeed, the 
 author guards himself by saying that his conclusions 
 have reference only to the basalts which he himself 
 has seen, and that if some day he can visit Auvergne 
 and the Vivarais, he perhaps may be better able to 
 discuss the question more generally, and to appreciate 
 what has been written on the other side. 2 His essay 
 was presented to the Institute of Sciences, and the two 
 referees, Hatty and Ramond, to whom it was submitted, 
 appended to their favourable report on it a most 
 judicious piece of advice to the young author. <C A 
 subject," they say, " where the analogies already 
 hazarded have led to more than one mistake, de- 
 mands the utmost caution in their use, and in a field 
 which the two parties dispute foot by foot, every step 
 should be justified by an observation and marked by 
 a fact. Citizen D'Aubuisson has never seen either 
 active or extinct volcanoes. Living till now in the 
 midst of aqueous formations, we should like him to 
 visit places where fire has manifested its empire. We 
 would especially desire that he should see the basalts of 
 Auvergne, which another disciple of Werner [Leopold 
 
 1 Traite de Geognosie (1819), vol. i. preface, p. xv. 
 
 2 Memoire sur les Basaltes de la Saxe, Paris, 1803, pp. 97, 100, 
 
 IOI. 
 
D'Aubuisson in Auvergne 243 
 
 von Buch] has just visited. That the citizen D'Aubuis- 
 son knows how to observe, is shown by his published 
 works, even if the memoir we have now been consider- 
 ing were not ample enough proof, and the interest of 
 his observations cannot be recognised in a manner 
 more useful to science than by encouraging him to 
 continue them." 
 
 D'Aubuisson lost no time in following the advice 
 thus given to him. He went to Auvergne and 
 found the basaltic rocks there lying on granite, 
 which in some valleys could be seen to be more 
 than 1 200 feet thick. If these basaltic rocks were 
 lavas, they must, according to the Wernerian doc- 
 trine, have resulted from the combustion of beds of 
 coal. But how could coal be supposed to exist under 
 granite, which was the first chemical precipitate of a 
 primeval ocean ? Such an infra-position was incon- 
 ceivable, and thus an apparent confirmation of the 
 Freiberg view of the aqueous origin of basalt was 
 at first obtained. But a very short time sufficed to 
 stagger the young geologist. He saw the perfect 
 craters with their rugged lava-streams, which he 
 followed along their branches into the valleys. It 
 was impossible to resist this evidence. " The facts 
 which I saw," he says, " spoke too plainly to be 
 mistaken ; the truth revealed itself too clearly before 
 my eyes, so that I must either have absolutely refused 
 the testimony of my senses in not seeing the truth, or 
 that of my conscience in not straightway making it 
 known. There can be no question that basalts of 
 volcanic origin occur in Auvergne and the Vivarais. 
 There are found in Saxony, and in basaltic districts 
 
244 D'Aubuissoris recantation 
 
 generally, masses of rock with an exactly similar 
 groundmass, which enclose exactly and exclusively 
 the same crystals, and which have exactly the same 
 structure in the field. There is not merely an 
 analogy, but a complete similarity ; and we cannot 
 escape from the conclusion that there has also been 
 an entire identity in formation and origin/' l 
 
 The frank and courageous Wernerian read his 
 recantation before the Institute of France the year 
 after his work on the Saxon basalts appeared. 2 Still 
 retaining his profound admiration for Werner, he 
 nevertheless relinquished one after another the peculiar 
 tenets of the Freiberg school, and became so impartial 
 a chronicler of geological progress, that in his remark- 
 ably able ^Treatise on Geognosy, though inclining, on the 
 whole, to his master's system, he did not entirely 
 
 l Geognosie, vol. ii. pp. 603, 605. Ch. Keferstein wrote a learned 
 disquisition on Basalt entitled " Beitrage zur Geschichte und 
 Kenntniss des Basaltes, und der ihm verwandten Massen," which 
 is contained in the Neue Schriften der Naturforschenden Gese Use haft 
 zu Halle, Band ii. 1819. The last part of the Memoir (pp. 139- 
 250) consists of a review of the various opinions which up to that 
 time had been expressed in regard to the nature of the rock, and 
 contains copious references to authorities. 
 
 2 " Sur les volcans et les basaltes de 1'Auvergne," read to the 
 Institute of Sciences in 1804 ; Journ. de Physique, torn. Iviii. p. 427, 
 lix. p. 367, Ixxxviii. (1819), p. 432 ; Soc. Philom. Bull. Paris, 1804, 
 p. 182. It is an indication of the slowness of the transmission of 
 scientific news in those days that in the English translation of 
 D'Aubuisson's Basalts of Saxony, which appeared at Edinburgh in 
 1814 that is, eleven years after the original the translator states 
 that he had heard of the author's having modified his views regarding 
 the basalts of Auvergne, but that he was not aware that he had 
 expressed any change of opinion in respect of those of Saxony. 
 
Early career of L. Von Buck 245 
 
 adopt it, but presented his facts and inferences in 
 such a manner that, as he himself claimed, even a 
 follower of Hutton would hardly find a few para- 
 graphs which he would wish to modify. D'Aubuisson 
 lived into his seventy-third year, and died in 1819. 
 
 We turn now to the story of Leopold von Buch 
 (1774-1853), the most illustrious geologist that Ger- 
 many has produced. He came of a good family, 
 which as far back as the twelfth century held an 
 important position in the district of Altmark. His 
 father, an ambassador in the Prussian service, had a 
 family of six sons and seven daughters. Leopold, the 
 sixth son, born on 25th April 1774, passed through 
 a short course of mineralogical and chemical teaching 
 at Berlin, and then went to Freiberg at the age of 
 sixteen, to place himself under the guidance of Werner. 
 He lived mostly under that great teacher's roof for 
 three years, having for part of the time as his com- 
 panion Alexander von Humboldt, with whom he then 
 began a lifelong friendship. From Freiberg, where he 
 drew in the pure Wernerian inspiration, he proceeded 
 to the University of Halle, and later to that of 
 Gottingen. For a brief period he held an appoint- 
 ment in the mining department of Silesia, but he 
 soon abandoned the trammels of official employment, 
 and having a sufficient competence for life, dedicated 
 himself heart and soul to independent geological 
 research. He was by far the most eminent of all 
 the band of active propagandists who, issuing from 
 Freiberg, spread themselves over Europe to illu- 
 mine the benighted natives with the true light of 
 Wernerianism. 
 
246 Von Buck's Early Writings and Travels 
 
 Von Buch's earlier writings were conceived after 
 the strictest rules of his master's system. In his first 
 separate work, a mineralogical description of Landeck, 
 he proclaimed, among other orthodox tenets of the 
 Freiberg school, his adhesion to the aqueous origin of 
 basalt, collected all the instances he could find of 
 organic remains in that rock, and boldly affirmed 
 that "it cannot be denied that Neptunism opens up 
 to the spirit of observation a far wider field than 
 does the volcanic theory." x 
 
 In the year 1797 Von Buch had his first view of 
 the Alps, and in the following year began his more 
 distant journeys, passing into Austria, and thence into 
 Italy, where he spent a considerable time among the 
 volcanic districts. In 1802 he published the first of 
 two volumes descriptive of these early travels. It was 
 appropriately dedicated to Werner, and expressed his 
 continued adhesion to the Wernerian faith. "Every 
 country and every district," he remarks, " where basalt 
 is found furnishes evidence directly opposed to all 
 idea that this remarkable rock has been erupted in a 
 molten condition, or still more that each basalt hill 
 marks the site of a volcano." 2 Before the second 
 volume appeared, the writer of that sentence had an 
 opportunity of visiting Auvergne. His conversion 
 there appears to have been as rapid as that of 
 
 1 Gesammelte Schriften, vol. i. p. 68. 
 
 2 Geognostische Eeobachtungen auf Reisen durch Deutschland und Italien, 
 Berlin, i. (1802), p. 126. It is a curious fact that A. von Humboldt 
 also began his geological career among the basalts of Germany, and 
 published in 1790 a little tract of 126 pages, entitled Mineralogische 
 Beobachtungen uber einige Basalte am Rhein. 
 
Buck in Auvergne 247 
 
 D'Aubuisson, but his announcement of it was much 
 more sensational. It was in the spring of 1802 that 
 he went to Central France, but owing to various 
 accidents the second volume of his travels did not 
 appear until the year iSc^. 1 He had made no secret, 
 however, of his change of opinion, for in the winter 
 following his French tour, a letter from him was pub- 
 lished, recommending a geologist who wanted to see 
 volcanoes to choose Auvergne rather than Vesuvius 
 or Etna. 2 His views were thus well known to Hatty 
 and Ramond when they recommended D'Aubuisson 
 to betake himself to the same volcanic region. 
 
 When his fuller account of his rambles in Auvergne 
 appeared, its very first sentence betrayed a curious 
 ignorance or forgetfulness of the literature of the 
 subject. " Here we are," he says, " in a region about 
 which the naturalists of France have talked so much, 
 to which they have persistently referred us, but which 
 they have never yet described to us." It is difficult 
 to believe that Von Buch had never seen Desmarest's 
 papers and accompanying maps. Yet throughout the 
 whole account which he gives of his excursions he does 
 not once refer to them, but writes as if he were almost 
 
 1 The descriptions of Auvergne are contained in an Appendix to 
 vol. ii., consisting of Mlneralogische Brlefe aus Auvergne an Herrn 
 Geh. Ober-Bergrath Karsten, p. 227 (1809). 
 
 ^Journal des Mines, vol. xiii. 1802-1803, p. 249. Boue, in an 
 obituary notice of Von Buch, says picturesquely that " in the year 
 1798 the learned geognost left Germany a Neptunist and came home 
 in 1800 a Vulcanist." His conversion, though as complete, was 
 not quite so rapid, for even after his visit to Italy and Central 
 France, though he gave up some parts of the Wernerian system, he 
 still clung tenaciously to others which he afterwards abandoned. 
 
248 Von Buck's recantation 
 
 the first geologist who had ever made any detailed and 
 exact observations in the country. 1 
 
 Nothing could be more explicit than Von Buch's 
 testimony to the volcanic origin of the basalts of 
 Auvergne. The marvellous cone and crater of the 
 Puy de Pariou excited, as they well might, his aston- 
 ishment and admiration. " Here," he says, " we find 
 a veritable model of the form and degradation of a 
 volcano, such as cannot be found so clearly either at 
 Etna or Vesuvius. Here at a glance we see how the 
 lava has opened a way for itself at the foot of the 
 volcano, how with its rough surface it has rushed 
 down to the lower grounds, how the cone has been 
 built above it out of loose slags which the volcano 
 has ejected from its large central crater. We infer 
 all this also at Vesuvius, but we do not always see it 
 there as we do at the Puy de Pariou." 
 
 Perhaps the most interesting passages in Von Buch's 
 brightly-written letters are to be found at the end. The 
 obviously volcanic origin of the rocks in Auvergne, 
 and their position immediately above a mass of granite 
 through which the craters had been opened, had 
 evidently powerfully impressed his mind. With all 
 these recent vivid experiences, he reflects upon his 
 earlier wanderings among the basalt hills of Germany, 
 and, as if taking his readers into his inner confidence, 
 he declares that "it is impossible to believe in a 
 
 1 He refers indeed several times to Montlosier's Essai sur les Folcans 
 <?4uvergne, which he calls an excellent work. In one passage he 
 actually credits this author with some of the most important 
 generalisations made by Desmarest. (Geog. Beobacht., pp. 279, 280.) 
 
 2 Op. cit, p. 240. 
 
Von Buck on Basalt 249 
 
 particular or local formation of basalt, or in its flow- 
 ing out as lava, when we know what the relations of 
 this rock are in Germany, and when we remember how 
 many different kinds of rocks are there associated 
 with basalt as essential accompaniments, how these 
 rocks form with basalt a connected whole which is 
 absolutely inconsistent with any notion of volcanic 
 action a peculiar coal formation, entirely distinct 
 from any other, only found with basalt and entirely 
 enclosed among basaltic rocks, often even a peculiar 
 formation of limestone." * 
 
 This was the one side of the picture. He could 
 not yet break entirely the Wernerian bonds that held 
 him to the beliefs he had imbibed at Freiberg. He 
 could not bring himself to admit that all that his 
 master had taught him as to the origin of basalt, all 
 that he had himself so carefully noted down from his 
 extended journeys in Germany, was radically wrong. 
 He, no doubt, felt that it was not merely a question 
 of the mode of origin of a single kind of stone. 
 The whole doctrine of the chemical precipitation of 
 the rocks of the earth's crust was at stake. If he 
 surrendered it at one point, where was he to stop ? We 
 cannot wonder, therefore, that he still refused to permit 
 himself to question the truth of the Wernerian faith 
 in so far as the old basalts of Saxony and Silesia were 
 concerned. He comforted himself with the belief that 
 they at least, with all their associated sedimentary 
 strata, must have been deposited by water. 
 
 But when he turns round again to the clear evidence 
 displayed in Central France, he asks, " Is it the fault of 
 1 Op. tit. p. 309. 
 
250 Von Buck on Basalt 
 
 the geologist in Auvergne that the arguments which are 
 powerful in Germany have no effect on him here, even 
 though he does not dispute them ? May he not be 
 allowed in retort to ask whether the principles which so 
 obviously arise from the phenomena in Central France 
 are not also applicable to the German basalts ? At all 
 events, he may contend, we see very little connection 
 between these basalts and ours as regards relations of 
 structure. Would you have us give up our convictions 
 as to the principles which give grandeur, consistency, 
 and simplicity to the explanation of our Auvergne 
 mountains, and adopt views founded on relations 
 which are not to be seen here ? " * 
 
 Well might Von Buch conclude by saying that he 
 " stands perplexed and embarrassed." Whatever he 
 may think of the basalts of Auvergne, he will not 
 allow the Vulcanist to wrest his admissions to any 
 general conclusion with regard to the German basalts. 
 u Opinions are in opposition which only new observa- 
 tions can remove." 
 
 Von Buch's faith in the Wernerian interpretation of 
 volcanoes and basalt-hills had a rude shaking from his 
 excursions in Italy and Central France. His next 
 great journey taught him that Werner's scheme of 
 geological succession could not be maintained. Before 
 his volume descriptive of the Italian tour was published, 
 he had started for Norway, where he remained hard at 
 work for no less than two years. Among the vast mass 
 of important observations which he made, one that 
 must have greatly impressed him was that in which 
 he satisfied himself that the rocks in the Christiania 
 1 O/. '/. p. 310. 
 
Emancipation from IVernerianism 251 
 
 district could not be arranged according to the Wer- 
 nerian plan which there completely broke down. Von 
 Buch found a mass of granite lying among fossiliferous 
 limestones which were manifestly metamorphosed, and 
 were pierced by veins of granite, porphyry, and syenite. 
 Such observations did not lead him, any more than 
 those in Central France, to a formal renunciation of 
 Wernerianism. But they enabled him to take a wide 
 and independent view of Nature, and gradually to 
 emancipate himself from the narrower views in which 
 he had been trained at Freiberg. 1 
 
 Von Buch's memorable investigation of the proofs of 
 the recent uprise of Scandinavia contributed still further 
 to expand his geological horizon. When he announced 
 that the whole of the continent of Sweden from Fre- 
 derikshald to Abo is now slowly rising above the sea, 
 he did as much as any Vulcanist of his day in support 
 of the theory of the earth promulgated by Hutton. 
 
 A further emancipation from the tenets of Freiberg 
 was displayed by a series of papers on the mountain- 
 system of Germany, wherein Von Buch gave the first 
 clear description of the geological structure of Central 
 Europe. He declared that the more elevated moun- 
 tains had never been covered by the sea, as Werner 
 had taught, but were produced by successive ruptures 
 and uplifts of the terrestrial crust. In 1824 he pro- 
 duced a geological map of the whole of Germany in 
 forty-two sheets, the first large map of its kind to illus- 
 trate a great area of the European continent, and a 
 signal monument of its author's unwearied research 
 
 iSee his " Reise nach Norwegen und Lappland," Gesammelte 
 Schriften, vol. ii. p. 109. 
 
252 Labours of Von B^lch 
 
 and of his geological acumen. For more than sixty 
 years this distinguished man continued to enrich geo- 
 logical literature with memoirs contributed to scientific 
 societies and journals, and with independent works. 
 His earliest writings stamped him as an observer of 
 great sagacity and independence, and his reputation 
 rose higher every year, until he came to be the 
 acknowledged leader of geological science in Germany. 
 Pressing forward into every department of the science, 
 he illuminated it with the light of his penetrating 
 intellect. From the North Cape to the Canary Islands 
 there was hardly a region that he did not personally 
 explore, and not many that he did not describe. 
 With ceaseless industry and exhaustless versatility, he 
 ranged from the structure of the Alps to that of the 
 Cystideans, from the distribution of volcanoes to that 
 of Ammonites, from the details of minerals and rocks 
 to the deepest problems in the history of the globe. 1 
 
 His influence in his time was great. Though he 
 began as a Wernerian, he gradually and almost uncon- 
 sciously passed into the ranks of the Vulcanists. In 
 no respect did he show his independence and love of 
 truth more than in his long and enthusiastic researches 
 among volcanoes. No vulcanist could have worked 
 out more successfully than he did the structure and 
 history of the Canary Islands. 
 
 Among the leaders of geology in the first half of this 
 
 1 Von Buch's collected writings form four large closely-printed 
 octavo volumes. The Royal Society's Catalogue assigns I 5 3 separate 
 papers to him. For a biographical account of Von Buch see the 
 sketch by W. Haidinger in Jahrb. k. k. geol. Reichsanst. Band iv. 
 P- 2O 7> an( i tne notices prefixed to his collected works. 
 
Personal characteristics 253 
 
 century there was no figure more familiar all over 
 Europe than that of Von Buch. Living as a bachelor, 
 with no ties of home to restrain him, he would start off 
 from Berlin, make an excursion to perhaps a distant 
 district or foreign country, for the determination of 
 some geological point that interested him, and return, 
 without his friends knowing anything of his move- 
 ments. He made most of his journeys on foot, and 
 must have been a picturesque object as he trudged 
 along, stick in hand. He wore knee-breeches and 
 shoes, and the huge pockets of his overcoat were 
 usually crammed with note-books, maps, and geological 
 implements. His luggage, even when he came as far as 
 England, consisted only of a small baize bag, which 
 held a clean shirt and silk stockings. Few would 
 have supposed that the odd personage thus accoutred 
 was one of the greatest men of science of his time, an 
 honoured and welcome guest in every learned society 
 of Europe. He was not only familiar with the writings 
 of the geologists of his day, but knew the men person- 
 ally, visited them in their own countries, and with many 
 of them kept up a friendly and lively correspondence. 
 He had an extensive knowledge of the languages of 
 Europe, and had read widely not only in his own sub- 
 jects, but in allied sciences, in history, and in literature, 
 ancient and modern. Kindly, frank, outspoken, and 
 fearless, he was beloved and honoured by those who 
 deserved his friendship, and dreaded by those who did 
 not. With tender self-sacrifice he would take his blind 
 brother every year to Carlsbad, and with endless bene- 
 factions did he brighten the lives of many who survived 
 to mourn his loss. He died on 4th March 1853, in 
 
254 G. de Dolomieu 
 
 the seventy-ninth year of his age. A fitting monument 
 to his memory was raised by subscriptions from all over 
 Europe. In the picturesque region of Upper Austria, 
 not far from Steyer, a granite boulder 1 6 feet high that 
 had been borne by a former glacier from the Alps was 
 chosen as his cenotaph. The stone, chiselled into a flat 
 surface, bears inscribed upon it, with the reverence of 
 admirers in Germany, Belgium, France, England, and 
 Italy, the immortal name of Leopold von Buch. 1 
 
 While D'Aubuisson and Von Buch were, even in 
 Werner's lifetime, emancipating themselves from the 
 tenets of the Freiberg School, various other observers, 
 without definitely becoming controversialists, were pro- 
 viding a large body of material which eventually proved 
 of great service in the establishment of a sound geology. 
 Chief among them were those who devoted themselves 
 with such ardour to the study of the Italian volcanoes. 
 One of the most active and interesting of their number 
 was Gratet de Dolomieu (1750-1801), who, born in 
 Dauphine, died at the early age of fifty-one, after a 
 strangely eventful life. At the age of 25 he published 
 some works on science, for which he was elected a 
 correspondent of the Academy of Sciences of Paris. He 
 thereafter took to geological and mineralogical explora- 
 tion, making his journeys on foot, with a bag on his 
 back, and a hammer in his hand, and studying successively 
 the minerals and rocks of Portugal, Spain, Sicily, the 
 
 1 An account of the movement for the preparation of this monu- 
 ment will be found in Das Buch-Denkmal, a pamphlet by Ritter von 
 Hauer and Dr. Homes, published in Vienna in 1858. It gives 
 a portrait of Von Buch, and a view of the monument, with a 
 map showing the position of the site. 
 
Faujas de St. Fond 255 
 
 Lipari Islands, the Pyrenees, the Alps, the Apennines, 
 Central France, and the Vosges. He made extensive 
 collections of specimens, and published many memoirs 
 descriptive of the regions he visited. His attention was 
 especially drawn to the active and extinct volcanoes of 
 the Mediterranean basin. As far back as 1776 he 
 made the announcement that he had found in Portugal 
 evidence of volcanoes older than certain mountains of 
 limestone a statement which he supplemented in 1784 
 with further evidence from Sicily, proving the inter- 
 calation of ancient lavas among stratified deposits. 1 
 To this important discovery further reference will be 
 given on a later page. 
 
 Among his other writings allusion may here be 
 made to his little volume on the Lipari Isles, to the 
 paper in which, following Desmarest, he described 
 the old volcanoes of Central France, and to his 
 u Memoire sur les lies Ponces." 2 Though his theo- 
 retical views were not always sound, he was a careful 
 and indefatigable observer, and provided copious 
 material towards the establishment of the principles 
 of geology. To him more than perhaps to any of 
 his contemporaries is science indebted for recognising 
 and enforcing the connection of volcanoes with the 
 internal heat of the globe. 
 
 Faujas de St. Fond (1742-1819) did excellent 
 service by his splendid folio on the old volcanoes 
 of the Vivarais and the Velay a work lavishly illus- 
 trated with engravings, which, by showing so clearly 
 the association of columnar lavas with unmistakable 
 
 1 Journ. de Phys. xxiv., Septembre 1784, p. 191. 
 
 2 Journ. des Mlnes y vol. vii. (1798), pp. 393-405. 
 
256 Spallanzani, Breislak 
 
 volcanic cones, ought to have done much to arrest 
 the progress of the Freiberg doctrine of the aqueous 
 origin of basalt. 1 The same good observer undertook 
 a journey into the Western Isles of Scotland towards 
 the end of the eighteenth century, 2 when that region 
 was much less easily visited than it now is, and con- 
 vinced himself of the volcanic origin of the basalts 
 there, thus adding another important contribution to 
 the literature of volcanic geology. 
 
 Spallanzani (1729-1799), the illustrious professor of 
 Pavia, Reggio, and Modena, born in 1729, devoted 
 his earlier life to animal and vegetable physiology, 
 and was fifty years of age before he began to turn 
 his attention to geological questions. But from that 
 period onward he made many journeys in the basin of 
 the Mediterranean from Constantinople to Marseilles. 
 Of especial interest were his minute and picturesque 
 descriptions of the eruptions of Stromboli, which at 
 not a little personal risk he watched from a crevice 
 in the lava. His Travels in the Two Sicilies and in 
 some Parts of the Apennines contained a mass of careful 
 observations among the recent and extinct volcanoes of 
 Italy. 8 
 
 Another Italian vulcanist well worthy of remem- 
 brance was Scipio Breislak (1748-1826) who, born in 
 Rome and destined for the church, showed so strong a 
 bent for scientific pursuits that he was eventually made 
 professor of natural philosophy and mathematics at 
 
 1 Recherche* sur les Volcans eteints du Vivarais et du Velay, folio, 1778. 
 
 2 Voyage en Angleterre, en Ecosse, et aux lies Hebrides, ^ vols. 8vo, 
 1797. 
 
 3 Viaggji alle due Sic Hie, 1792-93. 
 
Montlosier 257 
 
 Ragusa, whence he passed to the Collegio Nazareno 
 at Rome. His fondness for geological studies led 
 to his appointment by Napoleon " Inspecteur des 
 poudres et salpetres" in the kingdom of Italy, 
 which gave him the opportunity of making himself 
 personally acquainted with the geology of a large 
 part of his native country. Powerful as an advocate 
 for the Vulcanist doctrines in opposition to the prevail- 
 ing Neptunism of his time, he wrote some excellent 
 monographs on the geology of different parts of 
 Italy, particular y of the Campania ; also an Intro- 
 duction to Geology, of which a French version was 
 published in 1812, and a more important treatise 
 which, translated into French from his Italian manu- 
 script, was published at Milan in three volumes in 
 1818. The attitude which Breislak took towards the 
 Freiberg School may be inferred from his remark 
 " I respect the standard raised by Werner, but the 
 flag of the marvellous and mysterious will never be 
 that which I shall choose to follow." * 
 
 Reference has been made in an earlier chapter 
 (p. 159) to F. D. de Reynaud, Comte de Montlosier 
 (1755-1838) who is chiefly known as a distinguished 
 French publicist. He went into exile at the time of 
 the French Revolution, but ultimately returned to 
 France, and in the end became a member of the 
 Chamber of Peers where, even when he had passed 
 his eightieth year, he continued to be one of the most 
 assiduous orators. He was the author of many political 
 writings, but deserves mention here for the small 
 treatise which he published in 1789 and which, as we 
 
 1 Introduzione alia Geologia, 2 vols. 8vo, 1811. 
 R 
 
258 Montlosier on Vulcanism 
 
 have seen, proved useful to Von Buch in Auvergne. 
 Montlosier, being an Auvergnat proprietor, had from 
 his boyhood been familiar with the physical features of 
 that interesting region. His Essai gives a lively ac- 
 count of the volcanic district from his own personal 
 rambles, but it contains nothing of importance that is 
 not to be found in the earlier writings of Desmarest, 
 whose views he adopts, but without citing him as his 
 authority. The last chapter of the Essai is devoted to 
 a discussion of the nature of volcanic force, which the 
 author regarded as something distinct from the " fire," 
 and perhaps of the nature of electricity, "the energy 
 whereof is increased under ground by chance encounter 
 with certain antagonistic materials." He was at all 
 events convinced that " neither coal, nor bitumen, nor 
 any of the other substances known to us can possibly 
 be the principle of volcanic force, which acts indiffer- 
 ently upon everything it meets with." 
 
 So long as the crude conception prevailed that 
 volcanic action was due to the combustion of beds 
 of coal or other inflammable materials, it was an 
 obvious consequence that the production of volcanoes 
 should be regarded as a comparatively modern feature 
 in the history of our planet. Not until thick forests 
 had flourished on the earth's surface, and had been 
 buried deep under accumulations of sediment, could 
 any subterranean conflagrations be expected to arise. 
 But there was yet another influence which could not 
 but retard the recognition of evidence of ancient 
 volcanic eruptions preserved among the strata of the 
 earth's crust. Hutton and his school, whose contri- 
 butions to geological progress will be described in 
 
Plutonist mews of Igneous Rocks 259 
 
 the next chapter, while they vigorously contended 
 for the igneous origin of the " whinstone " (basalt) 
 rocks, in opposition to the teachings of the Neptunists, 
 looked upon these rocks as " not of volcanic, nor of 
 aqueous, but certainly of igneous origin," having been 
 " formed, in the bowels of the earth, of melted matter 
 poured into the rents and openings of the strata." 1 
 So intent were the Plutonists on collecting all the 
 evidence they could find in favour of the deep-seated 
 and intrusive origin of these masses, that they naturally 
 neglected or explained away, in accordance with their 
 own theory, the cases where there was no evidence 
 of intrusion. The Neptunists, on the other hand, 
 seized upon these very cases in support of their 
 contention that sheets of basalt regularly inter- 
 stratified with aqueous deposits must themselves 
 have been precipitated from solution in water. The 
 disputants on neither side perceived that a third 
 and entirely distinct explanation of the facts could 
 be given. If the strata of sedimentary materials 
 were accumulated under water, as was universally 
 admitted, might not the sheets of basalt and other 
 presumably volcanic materials have been erupted 
 upon the floor of that water, whether sea or lake, 
 so as to alternate with the normal deposits of 
 sediment ? 
 
 Already two acute observers had led the way 
 towards this, the true solution of the apparent con- 
 tradiction, though neither school of combatants would 
 accept their explanation. Desmarest, as we have seen, 
 (p. 1 66) had declared as far back as 1775, that traces 
 1 Playfair's Illustrations of the Huttoman Theory, 234, 239. 
 
26 o Dolomieu on Submarine eruptions 
 
 of ancient subaqueous volcanic eruptions have been 
 preserved among the sedimentary strata that overlie the 
 granite of Auvergne. A year or two later, Dolomieu 
 pointed out the evidence for the contemporaneous 
 interstratification of volcanic sheets among ordinary 
 marine deposits. He first directed attention to the 
 subject in 1776, and brought forward still more clearly 
 in 1784 proofs of ancient eruptions preserved in a 
 series of marine limestones. 1 He showed that in 
 the Val di Noto in Sicily such limestones, abound- 
 ing in large corals and shells, attain a considerable 
 thickness and lie in horizontal beds of white rock, 
 alternating with numerous intercalations of dark vol- 
 canic material. He found in one section eleven such 
 prominent alternations, though if he had included the 
 layers not more than an inch thick, this number would 
 have been doubled. The volcanic material varied 
 from band to band, two-thirds consisting of frag- 
 mental detritus, and the remainder of sheets of 
 basalt, sometimes regularly columnar. The most 
 abundant constituent was a black sand or tuff, which 
 had been laid down in thin layers, with the coarsest 
 particles at the bottom. Some of the bands consisted 
 of a conglomerate made up of blocks of different 
 lavas cemented together in a calcareous or argillaceous 
 matrix. In all the limestones Dolomieu found volcanic 
 fragments to be generally present. He observed that 
 the basalt-sheets sometimes lie directly on a floor of 
 limestone, sometimes on a layer of aggregated cinders, 
 and that in the former case the two rocks are inter- 
 
 1 " Sur les Volcans teints du Val di Noto en Sicile," Journ. de 
 Physique, xxv., Septr. 1784, p. 191. 
 
Play fairs criticism of Dolomieu 261 
 
 mingled along the junction-plane. He rightly reasoned 
 that these facts demonstrate the contemporaneous dis- 
 charge of volcanic products over the sea-bottom, at the 
 time when the limestones were in process of accumula- 
 tion. He found a difficulty, however, in explaining 
 how the basalts could have flowed so far as perhaps ten 
 leagues, without becoming solid, and he thought that 
 the vents from which the eruptions proceeded in such 
 long succession must have rapidly risen above sea- 
 level, otherwise their fires would have been speedily 
 extinguished by the rush of the water down into their 
 craters. The submarine volcanic series of younger 
 Tertiary age in Sicily is now well known from the 
 labours of subsequent observers, but it is not always 
 pointed out that the credit of the original discovery 
 of it belongs to Dolomieu. 
 
 Play fair was fully acquainted with the arguments 
 of the French geologist, and refers to them with 
 characteristic candour. He brings forward what he 
 considers "insuperable objections" to them objec- 
 tions which in the light of present knowledge are 
 easily removable but he frankly admits the value 
 of Dolomieu's explanation of the facts by granting 
 that " it makes a considerable approach to a true 
 theory, and that the submarine volcanoes of Dolo- 
 mieu have an affinity to the unerupted lavas of Dr. 
 Hutton." 1 
 
 The long continuance of the Huttonian prejudice 
 in favour of these " unerupted lavas " can hardly 
 be better illustrated than by reference to the Descrip- 
 tion of the Western Islands of Scotland, by John 
 1 Illustrations, 243. 
 
262 y. Macculloch, K. C. von Leonhard 
 
 Macculloch (1773-1835), published in 1819. This 
 now classic work undoubtedly gave a great impetus 
 to geological progress, especially in the department of 
 the science which deals with the igneous rocks. The 
 number and striking character of the illustrations 
 which it afforded of the truly eruptive nature of 
 these rocks did much to strengthen the Plutonist 
 cause throughout the world. Yet though the region 
 described included the great basalt-plateaux of the 
 Inner Hebrides, with what we now recognise to be 
 their abundant evidence of the superficial outpouring 
 of streams of basic lava and showers of volcanic 
 ashes, in continuous sequence, as clearly exposed 
 along hundreds of miles of sea-precipices, no reader 
 of Macculloch's volumes would be likely to gather 
 from them that any such record of prolonged volcanic 
 activity is to be found in the West of Scotland. Even 
 so late as the year 1832, K. C. von Leonhard, in 
 his ample monograph on Die Basalt-Gebilde, fully 
 describes the volcanic features of these rocks as dis- 
 played in Auvergne, the Eifel and other districts, but 
 when he comes to deal with the sheets of basalt 
 intercalated among the strata of the Earth's crust, he 
 is chiefly careful to mark their connection with dykes, 
 and the proofs they furnish that they have been injected 
 into and have altered the contiguous strata. It would 
 almost appear that if in the earlier years of last century 
 a Vulcanist had maintained the contemporaneity of a 
 basalt-sheet with the sedimentary deposits among which 
 it lay, he would have run some risk of being regarded 
 as having gone over to the Neptunist camp. 
 
 Notwithstanding the lessons so clearly taught by 
 
Slow progress of Volcanic Geology 263 
 
 Desmarest from the structure of Auvergne, and by 
 Dolomieu from that of the Val di Noto, many years 
 had to pass away before it began to be generally 
 realised that all the sheets of igneous material inter- 
 calated among the sedimentary formations of the 
 terrestrial crust are not plutonic intrusions, but that 
 not a few of them are unquestionably lavas and 
 ashes, thrown out by once active volcanoes, either 
 under the sea or on land. Only by slow steps of 
 investigation was the truth at last ascertained and 
 admitted that volcanic action has been abundant all 
 over the globe, from the earliest geological times, and 
 that a record of its successive phases has been pre- 
 served among the rocks. 
 
 When at last the controversy as to the origin of 
 basalt, and the eruptive character of the so-called 
 "Trap-rocks" had been settled, and men were able, 
 apart from the disputes of the rival schools, to look at 
 these rocks impartially, with the view of learning what 
 record they have to contribute to the history of the 
 earth, it was fitting that progress in this subject should 
 begin to be made in Britain a portion of the earth's 
 surface which, for its size, contains a fuller chronicle 
 of past volcanic activity than any other land hitherto 
 examined. A brief outline of the early stages of this 
 research within the British Isles will show how slowly 
 yet how securely the foundation stones in this depart- 
 ment of geology were laid. 
 
 Among the followers of the Wernerian faith who 
 early emancipated themselves from Werner's doctrines 
 regarding volcanic rocks, an honourable, place must 
 be assigned to Ami Bou (1794-1881). Born in 
 
264 Ami Boue 
 
 Hamburg, but of Swiss parentage and old French, 
 descent, he was sent for his medical education to the 
 University of Edinburgh, where he graduated as 
 M.D. in the year 1816. But his strong bent 
 towards natural history pursuits led him to take up 
 geology, in which he was trained after the Wer- 
 nerian system by Jameson. He rambled far and 
 wide over Scotland, and formed his own conclu- 
 sions as to the origin and age of many of the igneous 
 rocks so abundantly developed in that country. Leav- 
 ing Edinburgh, he settled for a time in Paris, and while 
 there, wrote an excellent treatise in French, with the 
 title of Essai Geologique sur I'Ecosse, which though it 
 bears no date, appears to have been published in the 
 year 1820. In many respects this remarkable work 
 was far in advance of its time, particularly in regard 
 to the views expressed in it regarding the trappean 
 rocks. Boue's acute eyes recognised the volcanic 
 nature of the great series of " roches feldspathiques 
 et trappeennes " of central Scotland, which he claimed 
 to mark eruptions in the time of the Old Red Sand- 
 stone. He boldly introduced for the first time, into- 
 the geological table for that country, a division entitled 
 " Terrain Volcanique," wherein he included not only 
 the younger basalts of the Inner Hebrides which 
 had been described by Faujas St. Fond, Macculloch 
 and others, but also the basalts, andesites, trachytes > 
 tuffs and other rocks intercalated in the Carboniferous 
 system. 
 
 On the other hand, Charles Daubeny (1795-1867) 
 another pupil of Jameson, who afterwards wrote an. 
 excellent treatise on volcanoes, could so late as 1821 
 
Charles Daubeny, Henry T. De la Beche 265 
 
 still speak of granite passing into sandstone, of " fire 
 and water, although such opposite agents, having in 
 some instances, produced effects nearly, if not alto- 
 gether identical," and of the probability that what is 
 now known to be a typical and admirable series of 
 alternations of basalt-lavas with tuffs and sedimentary 
 fossiliferous strata, was entirely the product of aqueous 
 deposition. 1 
 
 But in the third and fourth decades of the nine- 
 teenth century a number of independent observers had 
 their attention aroused by the intercalation of rocks 
 which they could only regard as volcanic, among the 
 older stratified formations of Britain. In his singularly 
 suggestive volume entitled Researches in Theoretical 
 Geology r , published in 1831, Henry Thomas De la Beche 
 (1796-1855) expressed, though cautiously, his opinion 
 that some at least of the " trappean " rocks associated 
 with the lower parts of the " grauwacke series " in 
 different countries of Europe, appear to have been 
 contemporaneous with the strata among which they lie, 
 " precisely as a bed of lava may flow over a sandy 
 
 1 Letters to Professor Jameson, Edln. Phil. Journ., 1820-21. In 
 Conybeare's Introduction to Conybeare and Phillips* Outlines of the 
 Geology of England and Wales, published in 1822, regretful reference 
 is made to the " excessive addiction to theoretical speculations " on 
 the part of the zealous rival partizans of the Huttonian and 
 Wernerian systems at Edinburgh. The author refrains from pro- 
 nouncing any judgment on the controversy as to the origin of 
 the Trap rocks, being desirous " to keep these conjectural specula- 
 tions entirely distinct from that positive knowledge, acquired from 
 observation, which is as yet the only certain portion of geological 
 science." One can see that, in spite of this laudable caution, 
 Conybeare's sympathies were rather in favour of the igneous 
 views. 
 
266 De la Beche on Ancient Volcanoes 
 
 bottom and afterwards be covered up by a deposit of 
 sand or mud." He had himself observed considerable 
 accumulations of " comminuted trappean matter " among 
 the greenstones and porphyries of the older grauwacke 
 of Devon and Cornwall, and was inclined to believe 
 them to represent volcanic ashes ejected at the time 
 that the associated sediments were in course of de- 
 position. He was thus led to suppose " that there 
 had been ejections of igneous matter into the atmo- 
 sphere or beneath shallow water, and consequently that 
 we might expect to discover similar facts among the 
 other fossiliferous rocks, under favourable circumstances 
 and in different parts of the world." 1 
 
 While these observations were in progress in the 
 south of England, another series on a larger scale was 
 advancing in the Lake District of the north. In that 
 mountainous tract Adam Sedgwick (1785-1873) had 
 spent some years, tracing the intricate structure of the 
 ground, and had found a great group of green slates 
 and porphyries, comprising fine compact slates with 
 coarse granular concretionary masses and breccias or 
 pseudo-breccias ; likewise amorphous, semi-columnar, 
 prismatic porphyries, which did not take the form of 
 dykes nor altered the limestone that rests upon them. 
 He therefore " inferred that the whole group is of 
 
 1 Op. /. pp. 384, 385. The "ashes" here referred to are of 
 Middle Devonian age. He also recognised the probable con- 
 temporaneous eruption of the trappean rocks associated with the 
 much younger red conglomerate of South Devon which may be 
 Permian. Geological Manual, 1831, p. 389. The progress of the 
 Geological Survey in later years enabled De la Beche to add 
 fresh details regarding the Lower Silurian volcanic rocks of Southern 
 Wales. Mem. Geol. Survey, vol. i. (1846) pp. 29-36. 
 
Sedgwick on Palceozoic Volcanoes 267 
 
 one formation which has originated in the simul- 
 taneous action of aqueous and igneous causes long 
 continued." 1 
 
 Sedgwick next turned his attention to the compli- 
 cated geological structure of the mountainous region of 
 North Wales, and after great labour succeeded in 
 unravelling it. Among the important additions to 
 geological science made by him at this time was 
 the recognition of the intercalation of vast masses of 
 igneous rocks among the ancient sedimentary series 
 (Cambrian and Lower Silurian) of that region. He 
 distinguished trappean conglomerates, contemporaneous 
 sheets of " felstone-porphyry " and " felstone," and 
 found the two classes of aqueous and igneous rocks 
 so interlaced that they could not be separated and were 
 regarded by him as of contemporaneous origin. He 
 likewise noted the presence of later intrusions of 
 " greenstone " and other trappean masses. Thus the 
 existence of a vast complex of ancient Palaeozoic lavas, 
 tuffs, and breccias was introduced into geological 
 literature. 2 
 
 While the Woodwardian Professor was at work 
 
 1 Proc. Geol. Soc. vol. i. p. 248 (5th January, 1831) and p. 400 
 (2nd May, 1832). 
 
 2 Proc. Geol. Soc. ii. (1838) pp. 678-9; iii. (1841) p. 548 ; iv. 
 (1843) p. 215. Quart. Journ. Geol. Soc. i. (1843) pp. 8-17; iii. 
 (1846) p. 134. In the last cited paper Professor Sedgwick speaks 
 -of at least ninety hundredths of the trappean rocks of North Wales 
 being of contemporaneous origin with their associated strata ; but 
 he regards them all as essentially "subaqueous or plutonic." He 
 shows how they have been involved in all the latter plication of 
 the region, and how they may be used as recognisable and well- 
 defined stratigraphical platforms. 
 
268 Murchisons Volcanic Researches 
 
 in North Wales his friend Roderick Impey Murchison 
 (1792-1871) was engaged on the borders of the 
 Principality in attacking the sedimentary (grauwacke) 
 strata that emerge from under the base of the Old Red 
 Sandstone, as will be more particularly noticed in 
 Chapter XIII. He had not advanced far in this 
 investigation before he in turn was confronted with 
 many examples of what were evidently igneous rocks,, 
 intercalated among the stratified formations to which 
 he was more specially directing his attention. In one 
 of his papers, read before the Geological Society in 
 1824, he shows at what an early period in his inquiries 
 he had detected proofs of true volcanic masses associ- 
 ated with these formations. He there remarks " that as 
 some of the porphyritic and felspathic rocks alternate 
 conformably with strata of marine origin, containing 
 organic remains of a very early period, and as some of 
 the layers in which such remains are imbedded have 
 a base of true volcanic matter, the date of the origin of 
 this class of rock is thereby fixed. These conformable 
 alternations of trap and marine sediment establish a 
 direct analogy between their mode of production and 
 those replications of volcanic ejections and marine 
 deposit which are now going on beneath the present 
 seas ; whilst they further explain the manner in which, 
 in times of the highest geological antiquity, the porphyry- 
 slates were arranged in parallel laminas with the sedi- 
 mentary accumulations of that age. The existence of 
 certain strata containing organic remains, yet possessing 
 a matrix composed in great measure of the same 
 materials as the adjacent ridges of trap-rock, has 
 strengthened the inference that some of the ebullitions 
 
Hay Cunningham, Charles Maclaren 269 
 
 of these submarine volcanoes were contemporaneous 
 with the period in which these animals lived and died, 
 the finer volcanic ejections having, it is presumed, led 
 to the formation of the volcanic sandstone." 1 
 
 In Scotland, after the war between the Plutonists and 
 the Neptunists had ceased, a period of calm, almost of 
 stagnation ensued, so far at least as regarded the inves- 
 tigation of igneous rocks. While it was now generally 
 conceded that these rocks had really resulted from the 
 action of subterranean causes, the old Huttonian idea 
 still prevailed that they had all been injected among 
 the strata at some depth beneath the surface. Even 
 so late as 1834 when Hay Cunningham, a pupil of 
 Jameson, began to prepare the materials for his essay 
 on "The Geology of the Lothians,'"^ he failed to 
 distinguish between the intrusive and contempor- 
 aneously intercalated sheets of igneous rock, although 
 each series is admirably developed in the region which 
 he had to investigate and describe. In the year 1839 
 there was published by far the most important treatise 
 that had yet been devoted to the description of any por- 
 tion of the ancient volcanic rocks of Britain the Sketch 
 of the Geology of Fife and the Lothians by Charles 
 Maclaren. In this classic work the structure of two 
 groups of hills Arthur's Seat and the Pentlands was 
 worked out in ample detail, and the volcanic history of 
 each of them was admirably traced. In the one case, 
 
 l Proc. Geol. Soc. ii. (1834) p. 92. Fuller discussion of the subject, 
 with ample local details, was given in his Silurian System, which was 
 published at the end of 1838. See especially pp. 225, 258, 268, 
 287, 317, 324 and 401. 
 
 2 Mem. Werner 'Ian Soc. vol. vii. 
 
270 The Geological Survey of Great Britain 
 
 the successive outflows of a series of " clay stone "" 
 " clinkstone " and " porphyry " lavas, from subaqueous- 
 craters or fissures, belonging to the time of the Old 
 Red Sandstone, was demonstrated by conclusive proofs, 
 In the other, the combination of subterranean injec- 
 tion and superficial outflow from a crater of Lower 
 Carboniferous age was clearly shown, together with 
 evidence of alternations of basalt-lavas with volcanic 
 tuffs, succeeded by prolonged denudation and a 
 subsequent renewal of volcanic activity on the same 
 site. The author, by appeals to the known behaviour 
 of modern volcanoes, illustrated each main feature in 
 the history of these ancient centres of eruption. His 
 convincing and suggestive essay ought to have 
 immediately stimulated the investigation of the subject 
 in other parts of the same region, where innumerable 
 examples of the phenomena, on even a more striking 
 scale, remained still unknown or misunderstood. But 
 Maclaren did not himself continue his volcanic 
 researches, nor for nearly twenty years did any one 
 arise to take up again the work which he had sa 
 well begun. 
 
 The Geological Survey in Wales developed with 
 great detail the history of the igneous rocks which 
 had been briefly noticed by Sedgwick and Mur- 
 chison. Subsequently the extension of the Survey 
 to Scotland in 1854 brought to light the remarkable 
 fulness of the volcanic record in that kingdom. 
 Gradually this record has been deciphered for the 
 whole of the British Isles, which are now found to 
 include a singularly varied and prolonged succession 
 of volcanic rocks, extending through Palaeozoic time 
 
Progress of Volcanic Geology abroad 271 
 
 and another wide-spread and complicated series dating 
 from the older part of the Tertiary period. 1 
 
 It is unnecessary to trace the progress of investi- 
 gation in other countries regarding the volcanic action 
 of former geological periods. In Germany, the lavas 
 and tuffs of Devonian and Permian age have long 
 been made familiar by many able writers. In France, 
 besides the complicated history of the Tertiary volcanic 
 history which, first sketched in broad outline by 
 Desmarest, has been followed into the minutest details 
 by Fouque, Michel Levy, Boule and other observers, 
 a great series of Palaeozoic eruptions has been 
 brought to light by Barrois. In the United States 
 also, a long and complicated volcanic record, dating 
 from older Tertiary time, has been made known by 
 the geologists of the various surveys which have been 
 extended over the Western States and Territories. 
 And thus the present active volcanoes of the globe 
 have been shown to be the latest in a series which 
 can be traced backwards into the remotest geological 
 periods. 
 
 We have seen in the course of these chapters that 
 volcanoes and earthquakes were assumed, even as far 
 back as the time of the ancient Greeks and Romans, 
 to be connected phenomena arising from one common 
 cause, but that no attempt was made during all the 
 subsequent centuries either by close observation or 
 well-devised experiment to discover what this active - 
 cause might be. The prevalent opinion was that 
 which looked upon subterranean wind as the main 
 
 1 I have given a full account of this volcanic history in my 
 Ancient Volcanoes of Great Britain, 2 vols., 1897. 
 
 J 
 
272 Early investigations of Earthquakes 
 
 agent of commotion, aided by the collapse of the 
 
 roofs or sides of underground caverns. When the 
 
 disturbance of the air in these recesses reached a 
 
 I maximum of intensity its friction or that of falling 
 
 / masses of loosened rock set fire to combustible mate- 
 
 \ rials, and eventually the wind and hot vapours forced 
 
 \their way with violence to the surface in volcanic 
 
 explosions. That earthquakes are common in volcanic 
 
 districts had been recognised from the earliest times, 
 
 but they had been experienced also in regions where 
 
 there were no active volcanoes. In the latter case 
 
 they were regarded as volcanic convulsions which had 
 
 not succeeded in opening a vent above ground. But 
 
 down to the middle of the eighteenth century no real 
 
 progress had been made in the solution of the problem 
 
 of their origin. 
 
 The year 1750 was remarkable for the number of 
 earthquakes which at that time affected the west of 
 Europe, and which caused some alarm in the south 
 of England. The Royal Society collected and pub- 
 lished the narratives of many observers, and likewise 
 some lucubrations on the " philosophy of earthquakes." 
 The same century was distinguished for its great activity 
 and rapid advance in the investigation of electricity. 
 This new and still mysterious force, so stupendous, 
 sudden and swift in its operation, seemed to some 
 minds to offer a probable explanation of the pheno- 
 mena of earthquakes. The earliest writer who tried 
 to picture to himself the manner in which electricity 
 acts in the process seems to have been Dr. Stukeley, 
 who contributed several communications on the subject 
 to the Philosophical Transactions of the Royal Society. 
 
Stukeley and Michell on Earthquakes 273 
 
 He " did not enter into the common notion of 
 struggles between subterraneous winds, or fires, 
 vapours or waters, that heaved up the ground like 
 animal convulsions ; but always thought it was an 
 electrical shock, exactly of the same nature as those, 
 now become very familiar in electrical experiments." 
 In one passage he remarks that, owing to peculiar 
 meteorological conditions, a wide extent of country 
 is sometimes brought into a highly electrified state 
 and that if then a " non-electric cloud " should dis- 
 charge its contents, in a heavy shower of rain, " an 
 earthquake must necessarily ensue." In another part 
 of the same essay he refers to "a black sulphureous 
 cloud " which comes " at a time when sulphureous 
 vapours are rising from the earth in greater quantity 
 than usual ; in which combined circumstances, the 
 ascending sulphureous vapours in the earth may pro- 
 bably take fire and thereby cause an earth-lightning, 
 which is at first kindled at the surface, and not at 
 great depths, as has been thought ; and the explosion 
 of this lightning is the immediate cause of an earth- 
 quake." * 
 
 Of a very different stamp from these crude specu- 
 lations was an essay by the Rev. John Michell 
 (1724-1793) read before the Royal Society in the 
 spring of the year 1760. During the decade that 
 had elapsed since the "earthquake year" of 1750, 
 western Europe had not ceased to be shaken, and 
 there had happened the great Lisbon earthquake of 
 ist November 1755 the most extensive and disas- 
 trous catastrophe which had ever been recorded. 
 l Phil. Trans, vol. xlvi. (1750), pp. 643, 676. 
 
274 Michell on Earthquakes 
 
 The keenest interest was consequently aroused in the 
 subject of earthquakes, and numerous reports from 
 eye-witnesses of the effects of that great disturbance 
 were printed in the 49th volume of the Philosophical 
 Transactions. Among the various papers Michell's 
 " Essay on the Causes and Phenomena of Earth- 
 quakes " stands out conspicuously as by far the most 
 important contribution to this branch of science that 
 had yet appeared in any language or country. Starting 
 on the assumption that earthquakes are due to the 
 sudden access of large quantities of water to subter- 
 ranean fires, whereby vapour is produced in sufficient 
 quantity and elastic force to give rise to the shock, 
 the author proceeds to adduce facts and arguments 
 in support of this hypothesis. In the course of the 
 discussion he points to the frequency of earthquakes 
 in the neighbourhood of active volcanoes, and to their 
 usual occurrence as accompaniments of volcanic erup- 
 tions. He states that the motion of the ground in 
 earthquakes is partly tremulous and partly propagated 
 by waves which, succeeding each other at intervals, 
 generally travel much further than the tremors. He 
 sees no difficulty in believing that subterranean fires 
 may continue to burn for long periods without the 
 access of air, and he adopts the idea that the spon- 
 taneous combustion of subterranean pyritous strata 
 among inflammable materials may be the cause of the 
 fires of volcanoes. If the vapours raised from these 
 fires, and finding an outlet at volcanic vents, are power- 
 ful enough to convulse the surrounding region to a 
 distance of ten or twenty miles, what may we not 
 expect from them when they are confined under 
 
Michell on Earthquakes 275 
 
 ground and prevented from escaping ? When the 
 roof above one of the volcanic fires falls into the 
 molten mass below it, all the water contained in the 
 fissures and cavities would be precipitated into the fire 
 and be almost instantly raised into vapour, which, by 
 its first effort, would form a cavity between the melted 
 matter and the superincumbent rock. This rock 
 would thus be first compressed, and then, on recovery, 
 dilated, producing a vibratory motion at the surface 
 of the ground, and partially occasioning the noise that 
 accompanies an earthquake, though this may also be 
 due to the grating of the parts of the earth together 
 during the wave-like motion through them. The 
 waves propagated through the earth are largest above 
 their source of origin, and gradually diminish until 
 they may only be detected by the motion of sheets 
 of water and objects suspended from a height, as 
 hanging branches and lamps in churches. 
 
 Michell further remarks that while earthquakes are 
 frequent in mountainous districts, they are usually less 
 extensive there than those which originate under the 
 sea, and he thinks that far more extensive fires may 
 exist below the ocean than on land, where the mass 
 of material lying above them is less. In seeking to 
 find the focus of origin of an earthquake, this acute 
 writer points out that if lines be drawn in the direction 
 of the observed track of the earth-waves through all 
 the places affected, " the place of their common inter- 
 section must be nearly the place sought." He shows 
 that the great Lisbon earthquake had its origin under 
 the Atlantic, somewhere between the latitudes of Lisbon 
 and Oporto. While admitting that a sufficient number 
 
276 Michell's Earthquake theory 
 
 of accurate data had not then been collected to 
 permit any satisfactory computation of the depth of 
 origin of earthquakes, which might considerably vary, 
 he yet thought that " some kind of guess might be 
 formed concerning it," and in illustration of such a 
 " random guess " he supposed that the depth at which 
 the Lisbon earthquake took its origin " could not be 
 much less than a mile, or a mile and a half, and pro- 
 bably did not exceed three miles." 
 
 From this brief summary of his opinions it will be 
 seen that Michell still laboured under the popular and 
 time-honoured delusion that volcanoes take their rise 
 from the combustion of inflammable strata below 
 ground, and that he attributed earthquakes exclusively 
 to the influence of these subterranean fires. Realising 
 that the sudden development of large bodies of vapour 
 within the terrestrial crust might start the disturbances 
 of earthquakes, he made a great onward step in show- 
 ing that successive waves would be generated in that 
 crust, and would travel outwards, in constantly diminish- 
 ing amplitude until they finally died away. It was 
 the first time that this conception of earthquake 
 motion had been laid before the world. Michell, 
 however, appears to have assumed the propagation of 
 the vapour to be the cause of the wave-like motion 
 of the ground. He speaks of the vapour "raising 
 the earth in a wave as it passes along between the 
 strata, which it may easily separate in an horizontal 
 direction." He refers to " the wave at the surface of 
 the earth occasioned by the passing of the vapour 
 under it," and states that "the shortest way that the 
 vapour could pass from near Lisbon to Loch Ness 
 
A. Perry, R> Mallet 277 
 
 was under the ocean." But with all his limitations 
 we may yet rank him as the great pioneer of the 
 modern science of Seismology. 1 
 
 It was not until about the middle of last century 
 that scientific methods and instrumental research began 
 to be seriously applied to the study of earthquake 
 phenomena, and the modern science of Seismology 
 came into being. Alexis Perry of Dijon had rendered 
 important service by laboriously collecting statistics 
 of earthquakes from all countries and of all ages 
 back to the early centuries of our era. But it is more 
 especially to the labours of Robert Mallet (1810- 
 1881) that we owe the initial impetus which has led 
 to such valuable results in recent years. In 1846 
 he published a paper " On the Dynamics of Earth- 
 quakes/' 2 which, as he himself says of it, was " the 
 first attempt to bring the phenomena of the earthquake 
 within the range of exact science, by reducing to system 
 the enormous mass of disconnected and often dis- 
 cordant and ill-observed facts which the multiplied 
 
 1 Michell was specially distinguished as an astronomer. After 
 serving various offices at the University of Cambridge, where he had 
 graduated as fourth wrangler, he became rector first of St. Botolph's, 
 Cambridge, and for the last twenty- six years of his life, of Thornhill 
 in Yorkshire. He was a Fellow of the Royal Society, and author 
 of a number of remarkable papers on astronomical subjects. His 
 essay on earthquakes may have led to his being appointed in 1762 
 to the Woodwardian Professorship of Geology at Cambridge, but 
 it appears to be his only contribution to geological science. Not 
 only does it treat of the subject of its title, but it gives an excellent 
 account of the tectonic arrangement of the stratified formations, to 
 which further reference will be made in a later chapter. 
 
 2 Trans. Roy. Irish Acad. vol. xxi. (1846), p. 51. 
 
278 Mallet's Earthquake Researches 
 
 narratives of earthquakes present, and educing from 
 these, by an appeal to the established laws of the higher 
 mechanics, a theory of earthquake motion." In this 
 his earliest contribution to the subject he announced 
 his famous definition of that motion as " the transit 
 of a wave of elastic compression in any direction, 
 from vertically upwards, to horizontally, in any 
 azimuth, through the surface and crust of the earth, 
 from any centre of impulse or from more than one, 
 and which may be attended with tidal and sound waves 
 dependent upon the former, and upon circumstances of 
 position as to sea and land." This epoch-making essay 
 was followed by his paper on the " Observation of 
 Earthquake Phenomena" contributed to the Admi- 
 ralty Manual of Scientific Enquiry in 1849, an ^ 
 thereafter by a voluminous series of Reports pub- 
 lished by the British Association for the Advancement 
 of Science from 1850 to 1858. These Reports 
 included a Catalogue of recorded earthquakes from 
 1606 B.C. to A.D. 1850, and a full discussion of the 
 facts and theory of earthquake phenomena. 
 
 Mallet's enthusiasm in the study of these phenomena 
 received a vivid stimulus from the occurrence of the 
 Neapolitan earthquake of December 1857 the third 
 in point of extent and severity hitherto experienced 
 in Europe. Under the auspices of the Royal Society, 
 he was enabled to visit the scene of devastation in 
 southern Italy, shortly after the calamity, and to make 
 careful observations of the effects upon buildings 
 and upon the surface of the ground. The results of 
 his investigation formed the subject of his work in 
 two volumes The First Principles of Observational Sets- 
 
Recent Earthquake Investigation 279 
 
 mology (Great Neapolitan Earthquake of 1857). Mallet 
 further contributed to our knowledge of the trans- 
 mission of waves of shock through the earth's crust 
 by exploding gunpowder and measuring the rate at 
 which the shock travels through different kinds of 
 materials, such as loose sand, on the one hand, and 
 solid granite, on the other. 
 
 The subsequent progress of seismology belongs 
 to a later time than falls within the limits marked 
 out for treatment here. The science has made a 
 great advance since Mallet's time, more particularly 
 as a consequence of the greater perfection of instru- 
 mental observation, and of the labours of Professor 
 John Milne and the native observers in Japan a 
 region where earthquakes are frequent and sometimes 
 of great violence. Such is the general interest in the 
 subject that observing stations, furnished with good 
 self-registering seismographs, are now to be found in 
 many parts of both hemispheres, and such is the 
 sensitiveness of these instruments that every severe 
 earthquake is detected and registered even at the 
 antipodes of the region from which it originates. 
 
CHAPTER IX 
 
 RISE of the modern conception of the theory of the Earth. Hutton, 
 
 Playfair. 
 
 WHILE the din of geological warfare resounded across 
 Europe, and the followers of Werner, flaunting the 
 Neptunist flag in every corner of the continent, had 
 succeeded in making the system promulgated from 
 Freiberg almost supplant every other, a series of quiet 
 and desultory researches was in progress, which led 
 to the establishment of some of the fundamental 
 principles of modern geology. We have now to 
 turn our eyes to the northern part of the British 
 Isles, and to trace the career of a man who, with 
 singular sagacity, recognising early in life the essential 
 processes of geological change, devoted himself with 
 unwearied application to the task of watching their 
 effects, and collecting proofs of their operation, and 
 who combined the results of his observation and 
 reflection in a work which will ever remain one of 
 the great classics of science. In following the course 
 of his researches, we shall see another illustration of 
 the influence of environment on mental tendencies, 
 and mark how the sea-shores and mountains, the 
 
James Hut ton 281 
 
 glens and lowlands of Scotland have given form and 
 colour to the development of geological theory. 
 
 James Hutton (1726-1797) was born in Edinburgh 
 on the 3rd June 1726, and was educated at the High 
 School and University of that city. 1 His father, a 
 worthy citizen there, had held the office of City 
 Treasurer, but died while the son was still young, 
 to whom he left a small landed property in Berwick- 
 shire. While attending the logic lectures at the 
 University, Hutton's attention was arrested by a 
 reference to the fact that, although a single acid 
 suffices to dissolve the baser metals, two acids must 
 combine their strength to effect the solution of gold. 
 The professor, who had only used this illustration 
 in unfolding some general doctrine, may or may not 
 have made his pupil a good logician, but he certainly 
 made him a chemist, for from that time the young 
 student was drawn to chemistry by a force that 
 only became stronger as years went on. When at 
 seventeen years of age he had to select his profession 
 in life, he was placed as an apprentice in a lawyer's 
 office. But genius is irrepressible, and amid the 
 drudgery of the law the young clerk's chemistry 
 not infrequently came to the surface. He would be 
 found amusing himself and his fellow-apprentices 
 with chemical experiments, when he should have 
 been copying papers or studying legal proceedings, 
 
 1 For the biographical details in this sketch I am indebted to 
 the admirable "Biographical Account of Dr. James Hutton" by 
 his friend and illustrator, Playfair. This was first printed in the 
 Transactions of the Royal Society of Edinburgh, and will be found 
 in vol. iv. of Playfair's collected works 
 
282 Hut tons Education and Early Career 
 
 so that finally his master, seeing that law was evidently 
 not his bent, released him from his engagement, and 
 advised him to seek some other employment more 
 suited to his turn of mind. 
 
 Hutton accordingly, after a year's drudgery at law, 
 made choice of medicine as the profession most nearly 
 allied to chemistry, and most likely to allow him to 
 indulge his predilection for science. For three years 
 he prosecuted his medical studies at Edinburgh, and 
 thereafter, as was then the custom, repaired to the 
 Continent to complete his professional training. He 
 remained nearly two years in Paris, pursuing there 
 with ardour the studies of chemistry and anatomy. 
 Returning to Scotland by way of the Low Countries, 
 he took the degree of Doctor of Medicine at Leyden 
 in September 1749. 
 
 But the career of a physician seems to have grown 
 less attractive to him as the time came on for his 
 definitely settling in life. He may have been to 
 some extent influenced by the success of certain 
 chemical researches which he had years before begun 
 with a friend of kindred tastes researches which 
 had led to some valuable discoveries in connection 
 with the nature and production of sal ammoniac, and 
 which appeared to offer a reasonable prospect of 
 commercial success. In the end he abandoned all 
 thought of practising medicine, and resolved to 
 apply himself to farming. He was a man never 
 disposed to do things by halves. Having made up 
 his mind in favour of agriculture as his vocation, 
 he determined to take advantage of the best practical 
 instruction in the subject then available. Accordingly 
 
Hut ton as Farmer 283 
 
 in 1752 he betook himself to Norfolk, lived with a 
 Norfolk farmer, and entered with all the zest of a 
 young man of six-and-twenty into the rural sports 
 and little adventures which, in the intervals of labour, 
 formed the amusement of his host and his neighbours. 
 It appears to have been during this sojourn in East 
 Anglia that Hutton's mind first definitely turned to 
 mineralogy and geology. He made many journeys 
 on foot into different parts of England. In Norfolk 
 itself there was much to arouse his attention. Every 
 here and there, the underlying White Chalk came to 
 the surface, with its rows of fantastically-shaped black 
 flints. To the east, lay the Crag with its heaps of sea- 
 shells, stretching over many miles of the interior. To 
 the north, the sea had cut a range of cliffs in the 
 Boulder-clay which, with its masses of chalk and its 
 foreign stones, presented endless puzzles to an 
 inquirer. To the west, the shores of the Wash 
 showed the well-marked strata of Red Chalk and Car- 
 stone, emerging from underneath the White Chalk of 
 the interior. 
 
 Hutton tells, in one of his letters written from 
 Norfolk, that he had grown fond of studying the 
 surface of the earth, and was looking with anxious 
 curiosity into every pit or ditch or bed of a river 
 that fell in his way. 
 
 After spending about two years in Norfolk, he 
 took a tour into Flanders, with the view of com- 
 paring the husbandry there with that which he had 
 been studying in England. But his eyes were now 
 turned to what lay beneath the crops and their soils, 
 and he took note of the rocks and minerals of the 
 
284 Hut ton relinquishes Farming 
 
 districts through which he passed. At last, about 
 the end of the summer of 1754, he settled down 
 on his own paternal acres in Berwickshire, which he 
 cultivated after the most approved methods. For 
 fourteen years he remained immersed in rural pur- 
 suits, coming occasionally to Edinburgh and making, 
 from time to time, an excursion to some more distant 
 part of the kingdom. His neighbours in the country 
 probably looked upon him only as a good farmer, with 
 more intelligence, enterprise, culture and knowledge 
 of the world than were usual in their society, and 
 displaying a playful humour and liveliness of manner 
 which must have made his companionship extremely 
 pleasant. Probably not one of the lairds and farmers 
 in the South of Scotland, who met him at kirk and 
 market, had the least suspicion that this agreeable 
 neighbour of theirs was a man of surpassing genius, 
 who at that very time, amidst all the rural pursuits in 
 which he seemed to be absorbed, was meditating on 
 some of the profoundest problems in the history of the 
 earth, and was gathering materials for such a solution 
 of these problems as had never before been attempted. 
 The sal ammoniac manufacture had proved suc- 
 cessful, and from 1765 Hutton became a regular 
 co-partner in it. His farm, now brought into excel- 
 lent order, no longer afforded him the same interest 
 and occupation, and eventually he availed himself of 
 an opportunity of letting it to advantage. He deter- 
 mined about the year 1768 to give up a country life 
 and establish himself in Edinburgh, in order that, with 
 uninterrupted leisure, he might devote himself entirely 
 to scientific pursuits. 
 
Establishes himself in Edinburgh 285 
 
 The Scottish capital had not yet begun seriously to 
 suffer from the centripetal attractions of London. It 
 was the social centre of Scotland, and retained within 
 its walls most of the culture and intellect of that ancient 
 kingdom. Hutton, from his early and close connection 
 with Edinburgh, had many friends there, and, on his 
 return for permanent residence, was received at once 
 into the choicest society of the town. One of his most 
 intimate associates was Dr. Joseph Black, the famous 
 chemist to whom we owe the discovery of carbonic 
 acid. This sympathetic friend took the keenest interest 
 in Hutton's geological theories, and was able to contri- 
 bute to their formation and development. Hutton 
 himself acknowledges that one of his doctrines, that 
 of the influence of compression in modifying the 
 action of heat, was suggested by the researches of 
 Dr. Black. The chemist's calm judgment and exten- 
 sive knowledge were always at the command of his 
 more impulsive geological friend, and doubtless 
 proved of essential service in guiding him in his 
 speculations. 
 
 Another of Hutton's constant and intimate asso- 
 ciates was John Clerk of Eldon, best known as the 
 author of a work on naval tactics, and the inventor 
 of the method of breaking the enemy's line at sea, 
 which led to so many victories by the fleets of Great 
 Britain. A third member of his social circle, who 
 may be alluded to here, was the philosopher and 
 historian Adam Ferguson, a man of remarkable force 
 of character, who, to his various literary works, which 
 were translated into French and German, added the 
 distinction of a diplomatist, for in 1778-1779 he acted 
 
286 Hut ton's versatility 
 
 as Secretary of the Commission sent across the Atlantic 
 by Lord North to try to arrange the matters in dispute 
 between the mother country and her North American 
 colonies. 
 
 When Hutton found himself in these congenial 
 surroundings, with ample leisure at his command, 
 he appears to have turned at once to his first love 
 in science, by betaking himself to chemical experi- 
 ment. Even without the testimony of his biographer, 
 we have only to look at his published works to be 
 impressed by his unwearied industry, and by the extra- 
 ordinarily wide range of his studies. Though up to 
 the time of his settling in Edinburgh he had published 
 nothing, he had read extensively. There were hardly 
 any of the sciences, except the mathematical, to which 
 he did not turn his attention. He was a diligent 
 reader of voyages, travels and books of natural history, 
 carefully storing up the facts which seemed to him to 
 bear on the problems of the earth's history. He not 
 only prosecuted chemistry and mineralogy, but dis- 
 tinguished himself as a practical meteorologist by his 
 important contribution to the theory of rain. He 
 wrote a general system of physics and metaphysics in 
 one quarto volume, and no fewer than three massive 
 quartos were devoted by him to An Investigation of 
 the Principles of Knowledge, and of the Progress of Reason 
 from Sense to Science and Philosophy. At the time of 
 his death he was engaged upon a treatise on the 
 Elements of Agriculture. 
 
 Hutton was thus no narrow specialist, wrapped 
 up in the pursuit of one circumscribed section of 
 human inquiry. His mind ranged far and wide 
 
His geological environment 287 
 
 over many departments of knowledge. He took 
 the keenest interest in them all, and showed the 
 most vivid sympathy in their advancement. His 
 pleasure in every onward step made by science and 
 philosophy showed itself in the most lively demonstra- 
 tions. " He would rejoice," we are told by Playfair, 
 " over Watt's improvements on the steam-engine, or 
 Cook's discoveries in the South Seas, with all the 
 warmth of a man who was to share in the honour 
 or the profit about to accrue from them. The fire 
 of his expression, on such occasions, and the anima- 
 tion of his countenance and manner, are not to be 
 described ; they were always seen with great delight 
 by those who could enter into his sentiments ; and 
 often with great astonishment by those who could not." 
 While so much was congenial to his mental habits 
 in the friendly intercourse of Edinburgh society, there 
 was not less in the scenery around the city that would 
 stimulate his geological proclivities. He could not 
 take a walk in any direction without meeting with 
 illustrations of some of the problems for the solution of 
 which he was seeking. If he turned eastward, Arthur's 
 Seat and Salisbury Crags rose in front of him, with 
 their memorials of ancient volcanic eruptions. If he 
 strolled westward, the ravines of the Water of Leith 
 presented him with proofs of the erosive power of 
 running water, and with sections of the successive sea- 
 bottoms of the Carboniferous period. Even within the 
 walls of the city, the precipitous Castle Rock bore 
 witness to the energy with which in ancient times 
 molten material had been thrust into the crust of the 
 earth. 
 
a88 Huttoris elaboration of his Theory 
 
 No more admirable environment could possibly have 
 inspired a geologist than that in which Hutton now 
 began to work more sedulously at the study of the 
 former changes of the earth's surface. But he went far 
 afield in search of facts, and to test his interpretation 
 of them. He made journeys into different parts of 
 Scotland, where the phenomena which engaged his 
 attention seemed most likely to be well displayed. He 
 extended his excursions likewise into England and 
 Wales. For about thirty years, he had never ceased 
 to study the natural history of the globe, constantly 
 seeking to recognise the proofs of ancient terrestrial 
 revolutions, and to learn by what causes they had been 
 produced. He had been led to form a definite theory 
 or system which, by uniting and connecting the scattered 
 facts, furnished an intelligible explanation of them. 
 But he refrained from publishing it to the world. He 
 had communicated his views to one or two of his 
 friends, perhaps only to Dr. Black and Mr. Clerk, 
 whose judgment and approval were warmly given to 
 him. The world, however, might have had still a long 
 time to wait for the appearance of his dissertation, had 
 it not been for the interest that he took in the founda- 
 tion of the Royal Society of Edinburgh, which was 
 incorporated by Royal Charter in I783. 1 At one of 
 
 x The Royal Society had been preceded by the Philosophical 
 Society, out of which it sprang. Edinburgh at that time was famous 
 for the number of its clubs and convivial meetings, at some of which 
 Black and Hutton were constant companions. Various anecdotes 
 have been handed down of these two worthies and their intercourse, 
 of which the following may suffice as a specimen. "These attached 
 friends agreed in their opposition to the usual vulgar prejudices, and 
 frequently discoursed together upon the absurdity of many generally 
 
Hut tons ' Theory of the Earth ' 289 
 
 the early meetings of this Society he communicated a 
 concise account of his Theory of the Earth, which 
 appeared in the first volume of the Transactions. This 
 essay was afterwards expanded, with much ampler 
 details of observations and fuller application of principles 
 to the elucidation of the phenomena, and the enlarged 
 work appeared in two octavo volumes in the year 1795 
 with the title of Theory of the Earth, with Proofs and 
 
 received opinions, especially in regard to diet. On one occasion 
 they had a disquisition upon the inconsistency of abstaining from 
 feeding on the testaceous creatures of the land, while those of the 
 sea were considered as delicacies. Snails, for instance why not use 
 them as articles of food ? They were well known to be nutritious 
 and wholesome even sanative in some cases. The epicures, in 
 olden time, esteemed as a most delicious treat the snails fed in the 
 marble quarries of Lucca. The Italians still hold them in esteem. 
 The two philosophers, perfectly satisfied that their countrymen 
 were acting most absurdly in not making snails an ordinary article 
 of food, resolved themselves to set an example ; and accordingly, 
 having procured a number, caused them to be stewed for dinner. 
 No guests were invited to the banquet. The snails were in due 
 season served up ; but, alas ! great is the difference between theory 
 and practice so far from exciting the appetite, the smoking dish 
 acted in a diametrically opposite manner, and neither party felt 
 much inclination to partake of its contents. Nevertheless, if they 
 looked on the snails with disgust, they retained their awe for 
 each other ; so that each conceiving the symptoms of internal revolt 
 peculiar to himself, began, with infinite exertion to swallow in 
 very small quantities the mess which he internally loathed. Dr. 
 Black at length broke the ice, but in a delicate manner, as if to 
 sound the opinion of his messmate, ' Doctor, do you not think 
 
 that they taste a little a very little queer ? ' 4 D queer, 
 
 D - queer, indeed ; tak them awa', tak them awa' ! ' vociferated 
 Dr. Hutton, starting up from table and giving full vent to 
 his feelings of abhorrence." A Series of Original Portraits, by John 
 Kay (commonly known as Kay's Edinburgh Portraits), vol. i. p. 57. 
 
 T 
 
290 James Hut ton 
 
 Illustrations. After Hutton's death his friend Playfair 
 published in 1802 his classical Illustrations of the 
 Huttonian Theory. We are thus in possession of ample 
 information of the theoretical views adopted by Hutton, 
 and of the facts on which he based them. Before 
 considering these, however, it may be convenient to 
 follow the recorded incidents of his quiet and unevent- 
 ful life, that we may the better understand the manner 
 in which he worked, and the nature of the material by 
 which he tested and supported his conclusions. 
 
 It was one of the fundamental doctrines of Hutton's 
 system that the internal heat of the globe has in past 
 time shown its vigour by the intrusion of large masses 
 of molten material into the crust. He found many 
 examples of these operations on a small scale in the 
 neighbourhood of Edinburgh and in the lowlands of 
 Scotland. But he conceived that the same effects had 
 been produced in a far more colossal manner by the 
 protusion of large bodies of granite. This rock, which 
 Werner had so dogmatically affirmed to be the earliest 
 chemical precipitate from his primeval ocean, was 
 surmised by Hutton to be of igneous origin, and he 
 believed that, if its junctions with the surrounding 
 strata were examined, they would be found to furnish 
 proofs of the correctness of his inference. The 
 question could be easily tested in Scotland, where, both 
 in the Highlands and among the Southern Uplands, 
 large bodies of granite had long been known to form 
 important groups of mountains. Accordingly, during 
 a series of years, Hutton undertook a number of excur- 
 sions into various parts of his native country, and 
 returned from each of them laden with fresh illus- 
 
Excursions in Scotland 291 
 
 trations of the truth of the conclusions at which he had 
 arrived. At one time he was busy among the roots of 
 the Grampian Hills, at another he was to be seen 
 scouring the lonely moorlands of Galloway, or climbing 
 the precipices and glens of Arran. His visit to Glen 
 Tilt has been made memorable by Playfair's brief 
 account of it. 1 He had conjectured that in the bed of 
 the river Tilt actual demonstration might be found 
 that the Highland granite has disrupted the surround- 
 ing schists. Playfair describes how " no less than six 
 large veins of red granite were seen in the course of a 
 mile, traversing the black micaceous schistus, and 
 producing, by the contrast of colour, an effect that 
 might be striking even to an unskilful observer. The 
 sight of objects which verified at once so many impor- 
 tant conclusions in his system, filled him with delight ; 
 and as his feelings, on such occasions, were always 
 strongly expressed, the guides who accompanied him 
 were convinced that it must be nothing less than 
 the discovery of a vein of silver or gold that could 
 call forth such strong marks of joy and exultation." 
 Another of Hutton's fundamental generalisations 
 was tested in as vivid and successful a manner. He 
 taught that the ruins of an earlier world lie beneath 
 the secondary strata, and that where the base of these 
 strata can be seen, it will be found to reveal, by what 
 is now known as an unconformability, its relation 
 to the older rocks. He had at various points in Scot- 
 land satisfied himself by actual observation that this 
 relation holds good. But he determined to verify it 
 
 1 Hutton's account is in the portion of the third volume of his 
 Theory referred to in a note on p 297. 
 
292 Hut ton, Hall and Play fair 
 
 once more by examining the junction of the two 
 groups of rock along (the coast where the range of 
 the Lammermuir Hills 'plunges into the sea. Accom- 
 panied by his friend Sir James Hall, whose property 
 of Dunglass lay in the immediate neighbourhood, and 
 by his colleague and future biographer, Playfair, and 
 favoured with calm weather, he boated along these 
 picturesque shores until the unconformable junction 
 was reached. The vertical Silurian shales and grits 
 were found to protrude through, and to be wrapped 
 round by, the red sandstone and breccia. " Dr. 
 Hutton," Playfair writes, " was highly pleased with 
 appearances that set in so clear a light the different 
 formations of the parts which compose the exterior 
 crust of the earth, and where all the circumstances 
 were combined that could render the observation 
 satisfactory and precise. On us who saw these pheno- 
 mena for the first time, the impression made will not 
 easily be forgotten. The palpable evidence presented 
 to us of one of the most extraordinary and important 
 facts in the natural history of the earth, gave a reality 
 and substance to those theoretical speculations which, 
 however probable, had never till now been directly 
 authenticated by the testimony of the senses. We 
 often said to ourselves, what clearer evidence could 
 we have had of the different formation of these rocks, 
 and of the long interval which separated their forma- 
 tion, had we actually seen them emerging from the 
 bosom of the deep ? . . . The mind seemed to grow 
 giddy by looking so far into the abyss of time ; and 
 while we listened with earnestness and admiration to 
 the philosopher who was now unfolding to us the 
 
Hut tons person and mode of life 293 
 
 order and series of these wonderful events, we became 
 sensible how much further reason may sometimes go 
 than imagination can venture to follow." 
 
 Hutton's lithe active body betokened the unwearied 
 vigour of his mind. His high forehead, firmly 
 moulded features, keen observant eyes, and well- 
 shaped, rather aquiline nose, marked him out at once 
 as a man of strong intellect, while the gentleness that 
 beamed in his face was a reflex of the kindliness of 
 his nature. His plain dress, all of one colour, gave 
 a further indication of the unostentatious simplicity of 
 his character. 
 
 His mode of life was in harmonious keeping with 
 these personal traits. After working in his study 
 during the day he would invariably pass the evening 
 with his friends. " A brighter tint of gaiety and 
 cheerfulness spread itself over every countenance when 
 the doctor entered the room ; and the"^ philosopher 
 who had just descended from the sublimest specula- 
 tions of metaphysics or risen from the deepest re- 
 searches of geology, seated himself at the tea-table, 
 as much disengaged from thought, as cheerful and 
 gay, as the youngest of the company." His character 
 was distinguished by its transparent simplicity, its 
 frank openness, its absence of all that was little or 
 selfish, and its overflowing enthusiasm and vivacity. 
 In a company he was always one of the most ani- 
 mated speakers, his conversation full of ingenious and 
 original observation, showing wide information, from 
 which an excellent memory enabled him to draw end- 
 less illustrations of any subject that might be dis- 
 cussed, where, "when the subject admitted of it, the 
 
294 Huttoris last illness 
 
 witty and the ludicrous never failed to occupy a con- 
 siderable place." 
 
 Though his partnership in the chemical work 
 brought him considerable wealth, it made no differ- 
 ence in the quiet unostentatious life of a philosopher, 
 which he had led ever since he settled in Edinburgh. 
 A severe attack of illness in the summer of 1793 
 greatly reduced his strength, and though he recovered 
 from it and was able to resume his life of activity, a 
 second attack of the same ailment in the winter of 
 1796 terminated at last fatally on the 26th March, 
 1797, when he was in his seventy-first year. 
 
 Hutton's claim to rank high among the founders 
 of geology rests on no wide series of writings, like 
 those which Von Buch poured forth so copiously for 
 more than two generations. Nor was it proclaimed 
 by a host of devoted pupils, like those who spread 
 abroad the fame of Werner. It is based, so far at 
 least as geology is concerned, on one single work, 1 
 and on the elucidations of two friends and disciples. 
 
 On the 7th of March and 4th of April, 1785, 
 Hutton read to the Royal Society of Edinburgh his 
 Memoir on a " Theory of the Earth ; or an In- 
 vestigation of the Laws observable in the Com- 
 position, Dissolution and Restoration of Land upon 
 the Globe." Extending to no more than 96 quarto 
 pages, it was written in a quiet, logical manner, with 
 no attempt at display but with an apparent anxiety 
 to state the author's opinions as tersely as possible. 
 
 1 The first sketch and the expansion of it into two octavo 
 volumes may be regarded as practically one work, so far as the 
 originality of conception is concerned. 
 
His literary style 295 
 
 Probably no man realised then that this essay would 
 afterwards be regarded as marking a turning-point in 
 the history of geology. For some years it remained 
 without attracting notice from friend or foe. 1 
 
 For this neglect various causes have been assigned. 
 The title of the Memoir was perhaps unfortunate. 
 The words " Theory of the Earth " suggested still 
 another repetition of the endless speculations as to 
 the origin of things, of which men had grown weary. 
 System after system of this kind of speculation had 
 been proposed and had dropped into oblivion ; and no 
 doubt many of his contemporaries believed Hutton's 
 " Theory " to be one of the same ill-fated brood. 
 His friend Playfair admits that there were reasons in 
 the construction of the Memoir itself why it should 
 not have made its way more speedily into notice. 
 Its contents were too condensed, and contained too 
 little explanation of the grounds of the reasoning. Its 
 style was apt to be prolix and obscure. It appeared, 
 too, in the Transactions of a learned society which had 
 only recently been founded, and whose publications were 
 hardly yet known to the general world of science. 
 
 1 It does not appear to be generally known that Desmarest, de- 
 parting from his usual practice of not noticing the work of living 
 writers, wrote a long and careful notice of Hutton's Memoir of 
 1785 in the first volume of his Geographic Physique, published in 
 1794-1795. He disagrees with many of Hutton's views, such, for 
 instance, as that of the igneous origin of granite. But he 
 generously insists on the value of the observations with which the 
 Scottish writer had enriched the natural history of the earth and 
 the physical geography of Scotland. " It is to Scotland," he says, 
 "that Hutton's opponent must go to amend his results and sub- 
 stitute for them a more rational explanation" (p. 75)- 
 
296 Hut ton's Opponents 
 
 At last, after an interval of some five years, De 
 Luc assailed the " Theory " in a series of letters in 
 the Monthly Review for 1790 and 1791. So far as 
 we know, Hutton published no immediate reply to 
 these attacks. He had often been urged by his 
 friends to publish his entire work on the Theory of 
 the Earth, with all the proofs and illustrations which 
 had been accumulating in his hands for so many 
 years. He delayed the task, however, until, during 
 the convalescence from his first severe illness, he re- 
 ceived a copy of a strenuous attack upon his system 
 and its tendencies by Richard Kirwan, a well-known 
 Irish chemist and mineralogist of that day. 1 
 
 This assailant not only misconceived and misrepre- 
 sented the views which he criticized, but charged 
 their author with atheistic opinions. Weakened as he 
 was by illness, Hutton, with characteristic energy, the 
 very day after he received Kirwan's paper, began the 
 revision of his manuscript, and worked at it until he 
 was able to send it to the press. It appeared in 
 1795, tnat i s > ten 7 e ars after the first sketch of the 
 subject had been given to the Royal Society of Edin- 
 burgh. Besides embodying that sketch, it gave a 
 much fuller statement of his conclusions, and an 
 ampler presentation of the facts and observations on 
 which they were founded. It formed two octavo 
 volumes. Playfair tells us that a third volume, 
 
 1 " Examination of the Supposed Origin of Stony Substances," 
 read to the Royal Irish Academy, 3rd February, 1793, and pub- 
 lished in vol. v. of their Transactions, p. 51. For a crushing 
 exposure of Kirwan's mode of attack see Playfair's Illustrations of 
 the Huttonian Theory, 119, 418. 
 
Play f air's t Illustrations ' 297 
 
 necessary for the completion of the work, remained 
 in manuscript. 1 
 
 If Hutton's original sketch was defective in style 
 and arrangement, his larger work was even more 
 unfortunate in these respects. Its prolixity deterred 
 readers from its perusal. Yet it is a vast storehouse 
 of acute and accurate observation and luminous de- 
 duction, and it deserves to be carefully studied by 
 every geologist who wishes to comprehend the history 
 of his own science. 
 
 Fortunately for Hutton's fame and for the onward 
 march of geology, the philosopher numbered among 
 his friends the illustrious mathematician and natural 
 philosopher, John Playfair (1748-1819), who had been 
 closely associated with him in his later years, and was 
 intimately conversant with his geological opinions. 
 Gifted with a clear penetrating mind, a rare faculty 
 of orderly logical arrangement, and an English style 
 of altogether remarkable precision and elegance, he 
 was of all men best fitted to let the world know 
 what it owed to Hutton. Accordingly, after his 
 friend's death, he determined to prepare a more 
 popular and perspicuous account of Hutton's labours. 
 He gave in this work, first a clear statement of the 
 essential principles of Hutton's system, and then a 
 series of notes or essays upon different parts of the 
 
 J A portion of this precious manuscript containing six chapters 
 (iv.-ix.) came into the possession of Leonard Homer, F.R.S., who 
 presented it to the Geological Society of London. It remained 
 hardly noticed in the library of the Society until 1899, when at 
 my solicitation the Society printed and published it. This is the 
 only portion of the MS. now known to exist. 
 
298 Play fairs 'Illustrations' 
 
 system, combining in these a large amount of original 
 observation and reflection of his own. His volume 
 appeared in the spring of 1802, just five years after 
 Hutton's death, with the title of Illustrations of the 
 Huttonian Theory of the Earth. Of this great classic 
 it is impossible to speak too highly. After the lapse 
 of a century it may be read with as much profit and 
 pleasure as when it first appeared. For precision of 
 statement and felicity of language it has no superior 
 in English scientific literature. To its early inspira- 
 tion I owe a debt which I can never fully repay. 
 Upon every young student of geology I would im- 
 press the advantage of reading and re-reading, and 
 reading yet again this consummate masterpiece. How 
 different would geological literature be to-day if men 
 had tried to think and write like Playfair ! 
 
 There are thus three sources of information as to 
 Hutton's geological system his first sketch of 1785, 
 his two octavo volumes of 1795, w ^ tn tne portion of 
 the third volume published in 1899 and Playfair's 
 Illustrations of I8O2. 1 Let us now consider what were 
 his fundamental doctrines. 
 
 Although he called his system a Theory of the 
 Earth, Hutton's conceptions entirely differed from 
 those of the older cosmogonists, who thought them- 
 selves bound to begin by explaining the origin of 
 things, and who proceeded on a foundation of hypo- 
 thesis to erect a more or less fantastic edifice of mere 
 speculation. He, on the contrary, believed that it is 
 
 1 To these may be added the memoirs by Sir James Hall 
 which appeared after Hutton's death and from which some 
 interesting particulars may be gleaned as to the master's opinions. 
 
Hut ton's ' Theory of the Earth ' 299 
 
 the duty of science first to try to ascertain what evi- 
 dence there is in the earth itself that will throw light 
 upon the history of the planet. Instead of invoking 
 conjecture and hypothesis, he proceeded from the 
 very outset to collect the actual facts, and to marshall 
 these in such a way as to make them tell their own 
 story. Unlike Werner, he had no preconceived theory 
 about the origin of rocks, with which all the pheno- 
 mena of nature had to be made to agree. His theory 
 grew so naturally out of his observations that it 
 involved no speculation in regard to a large part 
 of its subject. 
 
 Hutton started with the grand conception that the 
 past history of our globe must be explained by what 
 can be seen to be happening now, or to have happened 
 only recently. The dominant idea in his philosophy is 
 that the present is the key to the past. We have 
 grown so familiar with this idea, it enters so intimately 
 into all our conceptions in regard to geological ques- 
 tions, that we do not readily realise the genius of 
 the man who first grasped it with unerring insight, 
 and made it the chief corner-stone of modern geology. 
 
 From the time of his youthful rambles in Norfolk, 
 Hutton had been struck with the universal proofs 
 that the surface of the earth has not always been as 
 it is to-day. Everywhere below the covering of soil 
 he found evidence of former conditions, entirely unlike 
 those visible now. In the great majority of cases, 
 he noticed that the rocks there to be seen consist of 
 strata, disposed in orderly arrangement parallel with 
 each other. Some of these strata are formed of 
 pudding-stone, others of sandstone, of shale, of lime- 
 
300 James Hut ton 
 
 stone, and so forth, differing in many respects from 
 each other, but agreeing in one essential character, 
 that they are composed of fragmentary or detrital 
 material, derived from rocks older than themselves. 
 He saw that these various strata could be exactly 
 paralleled among the accumulations now taking place 
 under the sea. The pudding-stones were, in his eyes, 
 only compacted gravels, the sandstones were indurated 
 sand, the limestones were in great part derived from 
 the aggregation of the remains of marine calcareous 
 organisms, the shales from the consolidation of mud 
 and silt. The wide extent of these strata, forming, 
 as they do, most of the dry land, seemed to him to 
 point to the sea as the only large expanse of water 
 in which they could have been deposited. 
 
 Thus corroborating the deductions of previous 
 observers, the first conclusion of the Scottish philo- 
 sopher was that the greater part of the land consists 
 of compacted sediment which, worn away from some 
 pre-existing continents, was spread out in strata over 
 the bed of the sea. He realised that the rocks thus 
 formed are not all of the same age, but, on the 
 contrary, bear witness to a succession of revolutions. 
 He acknowledged the existence of a series of ancient 
 rocks which he called Primary, not that he believed 
 them to be the original or first-formed rocks in the 
 structure of the planet, but that they were the oldest 
 that had then been discovered. They included the 
 various schists and slates which Werner claimed as 
 chemical precipitates, but in which Hutton could only 
 see the hardened and altered mechanical sediments of a 
 former ocean. Above them, and partly formed out of 
 
His mews on Consolidation of Strata 301 
 
 them, came the Secondary strata that constitute the 
 greater part of the land. 
 
 But all these sedimentary deposits have passed from 
 their original soft condition into that of solid stone. 
 Hutton attributed this change to the action of sub- 
 terranean heat. In his day, the chemistry of geology 
 was exceedingly imperfect, though in Hutton's hands 
 it was greatly less erroneous than in those of Werner. 
 The solubility of silica, for instance, and its capacity 
 for being introduced in aqueous solution into the 
 minutest crevices and pores of a rock, were not known. 
 It need not, therefore, surprise us to find that in 
 the Huttonian conception the flints in chalk were 
 injected into the rock in a molten state, and that 
 the agate of fossil wood bore marks of igneous fusion. 
 Hutton did not realise to what an extent mere 
 compression could solidify the materials of sedimentary 
 strata, nor how much may be done, by infiltration 
 and deposition between the clastic grains, towards 
 converting originally loose detritus into the most 
 compact kind of stone. But there was one kind of 
 compression which though not perhaps at first obvious, 
 was clearly perceived by him in its geological relations. 
 Following out ideas suggested to him by Black, he 
 saw that the influence of heat upon rocks must be 
 largely modified by pressure. The more volatile com- 
 ponents, which would be speedily driven off by a 
 high temperature at the surface of the earth, might 
 be retained under great pressure below that surface. 
 Hutton conceived that limestone might even be fused 
 in this way, and yet still keep its carbonic acid. This 
 idea was ridiculed at the time, but its truth was 
 
302 James Hut ton 
 
 confirmed afterwards by Hall's experiments, to which 
 I shall allude in the sequel. 
 
 The next step in Hutton's reasoning was that 
 whereby he sought to account for the present position 
 of the strata which, originally deposited under the sea, 
 are now found even on mountain-crests 15,000 feet 
 above sea-level. We have seen how Werner looked on 
 his vertical primitive strata as having been precipitated 
 from solution in that position, and as having been 
 uncovered by the gradual subsidence and disappearance 
 of the water. Hutton attacked the problem in a 
 different fashion. He saw that if the exposure of 
 the dry land had been due merely to the subsidence 
 of the sea, it would involve no change in the positions 
 of the strata relatively to each other. What were 
 first deposited should lie at the bottom, what were 
 last deposited, at the top ; and the whole should retain 
 their original flatness. 
 
 But the most cursory examination was, in his 
 opinion, sufficient to show that the actual conditions in 
 nature were entirely different from any such arrange- 
 ment. Wherever he went, he found, as Steno had 
 done, proofs that the sedimentary strata, now forming 
 most of the land, had in large measure lost the 
 horizontal or gently inclined position in which sedi- 
 mentary deposits are normally accumulated. He saw 
 them often inclined, sometimes placed on end, or even 
 stupendously contorted and ruptured. It was mani- 
 festly absurd, as De Saussure had shown in the Alps, 
 to suppose that pebbles in vertical beds of con- 
 glomerate could ever have been deposited in such 
 positions. And if some of the vertical strata could thus 
 
On Disturbance of Strata 303 
 
 be demonstrated to have been originally horizontal or 
 nearly so, there could be no reason for refusing to con- 
 cede that the same alteration had happened to the other 
 vertical strata, even although they might not afford 
 such obvious and convincing proofs of it. As Steno 
 had long before pointed out, no stratum could have 
 ended off abruptly at the time of its formation, unless 
 against a cliff or slope that arrested its detrital materials 
 from drifting further, nor could it have been accumu- 
 lated in plicated layers. But nothing is more common 
 than to find strata presenting their truncated ends to 
 the sky, while in some districts they are folded and 
 crumpled, like piles of carpets. Not only so, but 
 again and again, they are found to be sharply dis- 
 located, so that two totally different series are placed 
 parallel to each other. 
 
 Hutton recognised that these changes, which were 
 probably brought about at different periods, must be 
 attributed to some great convulsions which, from time 
 to time, have shaken the very foundations of the earth. 
 He could prove that, in some places, the Primary rocks 
 had in this way been broken up and placed on end 
 before the Secondary series was laid down, for, as on 
 the Berwickshire Coast, he had traced the older vertical 
 strata overlain and wrapped round by the younger hori- 
 zontal deposits, and had also observed, from the well- 
 worn fragments of the former enclosed in the latter, 
 that the interval of time represented by the break 
 between them must have been of considerable duration. 
 
 Having been led by this train of observation and 
 deduction, to the demonstration of former gigantic 
 disturbances, by which the bed of the sea had been 
 
304 James Hittton 
 
 upheaved and its hardened sediments had been tilted, 
 plicated and fractured, in order to form the existing 
 dry land, Hutton had next to look round for some 
 probable cause for these phenomena. He inferred 
 that the convulsions could only have been produced 
 by some force that acted from below upward, but was 
 so combined with the gravity and resistance of the 
 mass to which it was applied, as to create a lateral 
 and oblique thrust that gave rise to the contortions 
 of the strata. He did not pretend to be able to 
 explain the nature and operation of this subterranean 
 force, though he believed it to be essentially due to 
 the effects of heat. Far from sharing the ancient 
 misconception that volcanoes are due to the combus- 
 tion of inflammable substances, he connected them with 
 the high internal temperature of the globe, and regarded 
 them as " spiracles to the subterranean furnace in order 
 to prevent the unnecessary elevation of land, and fatal 
 effects of earthquakes/' 1 
 
 Unlike Werner, Hutton saw that while no mere 
 combustion of inflammable substances could account 
 for this high temperature of the subterranean regions, 
 the actual conditions involved must be so far different 
 from ordinary combustion as not improbably to require 
 no circulation of air, nor any supply of carbonaceous 
 or other materials as fuel. The nucleus of the globe 
 might accordingly "be a fluid mass, melted, but 
 unchanged by the action of heat." 
 
 In this way, appealing at every step to the actual 
 facts of nature, Hutton built up the first part of his 
 
 1 Theory of the Earth, vol. i. p. 146. It will be remembered that 
 a similar opinion was expressed by Strabo. 
 
On Intrusive Rocks 305 
 
 immortal Theory. Most of the facts cited by him 
 were more or less familiar to men ; and some of the 
 obvious inferences to be drawn from them had been 
 deduced by other observers before his time. But no 
 one until then had grouped them into a coherent 
 system by which the earth became, as it were, 1 her 
 own interpreter. The very obviousness and familiarity 
 of his doctrine at the present time, when it has become 
 the groundwork of modern geology, are apt to blind 
 us to the genius of the man who first conceived it, 
 and worked it into a harmonious and luminous whole. 
 
 In the course of his journeys in Scotland, Hutton 
 had come upon many examples of rocks that were not 
 stratified. Some of these occurred among the Primary 
 masses ; others were observable in the Secondary series. 
 Reflecting on the probable reaction of the heated 
 interior of the globe upon its outer cooler shell or 
 crust, he had come to the conclusion that many, if 
 not all, of these unstratified rocks were to be regarded 
 as material that had once been in a molten condition, 
 and had been injected from below during some of 
 the great convulsions indicated by the disturbed strata. 
 He distinguished three principal kinds of such intrusive 
 rocks " Whinstone," under which term he included a 
 miscellaneous series of dark, heavy, somewhat basic 
 rocks, now known as dolerites, basalts, diabases and 
 andesites ; Porphyry, which probably comprised such 
 rocks as felsite, orthophyre and quartz-porphyry ; and 
 Granite, which, though the term was generally used 
 by him in its modern sense, embraced some rocks of 
 more basic character. 
 
 He showed that the whinstones correspond so 
 
306 James Hut ton 
 
 closely to modern lavas in structure and composition, 
 that they may be regarded as probably also of volcanic 
 origin. But, as was discussed in Chapter VIII. (p. 259), 
 he did not suppose that they had actually been erupted 
 at the surface, like streams of lava. He found them 
 to occur sometimes in vertical veins, known in Scot- 
 land as dykes, a term now universal in English geolo- 
 gical literature, and sometimes as irregular bosses, or 
 interposed as sheets between the strata. He believed 
 these rocks to be masses of subterranean or unerupted 
 lava, but as we have seen, the grounds on which he 
 reached this conclusion were not always such as the sub- 
 sequent progress of inquiry has justified. The deduc- 
 tion was itself in many cases correct, but the reasoning 
 that led up to it, was partly fallacious. Hutton argued, 
 for instance, that the carbonate of lime, so commonly 
 observable in his " Whinstones " indicated that the 
 rock had been fused deep within the earth, under 
 such pressure as to keep that mineral in a molten 
 state, without the loss of its carbonic acid. Like 
 other mineralogists of his day, he was not aware that 
 the calcite of the amygdales has been subsequently 
 introduced in aqueous solution into the steam-cavities, 
 and that the diffused lime-carbonate in the body of 
 the rocks generally results from their partial decom- 
 position by infiltrating water. Much more accurate 
 were his observations that whinstone has greatly indu- 
 rated the strata into which it has been injected, even 
 involving and fusing fragments of them, and reducing 
 carbonaceous substances, such as coal, to the condition 
 of coke or charcoal ; that it has sometimes been 
 intruded among the strata with such violence as to 
 
On Whinstone and Granite 307 
 
 shift, upraise, bend and otherwise disturb them, and 
 that it can be seen to have been thrust abruptly into 
 one continuous succession of strata, which, above and 
 below it, are exactly alike, and have obviously been at 
 one time in contact with each other. 
 
 Granite, as Hutton pointed out, differs in many 
 important respects from " whinstone," more par- 
 ticularly in its position, for it was then believed to 
 lie beneath all the known rocks, rising to higher 
 elevations and sinking to greater depths than any 
 other material in the crust of the earth. Yet though 
 he admitted its infraposition, he differed from the 
 Neptunists in regard to its relative antiquity. He 
 believed it to be younger than the strata which rest 
 upon it, for he regarded it as a mass that had once 
 been melted and had been intruded among the rocks 
 with which it is now found associated. He supported 
 this conclusion by various arguments, chief among 
 which was one based on the occurrence of veins that 
 diverge from the granite and ramify through the sur- 
 rounding rocks, diminishing in width as they recede 
 from their parent mass (p. 291). 
 
 Properly to appreciate the value of these doctrines 
 in regard to the development of a sound geological 
 philosophy, we must bear in mind what were the 
 prevalent views entertained on the subject when 
 Hutton worked out his theory. We have seen that 
 granite, generally regarded as an aqueous formation, 
 was affirmed by Werner to have been the first pre- 
 cipitate that fell to the bottom from his universal 
 ocean. H. B. De Saussure, who had seen more of 
 granite and its relations to other rocks than Werner, or 
 
308 James Hut ton 
 
 indeed than any other geologist of his time, remained 
 up to the last a firm believer in the aqueous origin of 
 that rock. Even after the death of the great Swiss 
 geologist, Cuvier, sharing his opinions on these 
 matters, proclaimed as late as the year 1810 his 
 belief that De Saussure overthrew the doctrine of 
 central fire, or of a source of heat within the earth's 
 interior, demonstrated granite to be the oldest rock, 
 and proved it to have been formed in strata that 
 were deposited in water. 1 Nobody before Hutton's 
 time had been bold enough to imagine a series of 
 subterranean intrusions of molten matter. Those who 
 adopted his opinion on this subject were styled 
 Plutonists, and were looked upon as carrying out the 
 Vulcanist doctrines to still greater extravagance, " attri- 
 buting to the action of fire widely-diffused rocks which 
 nobody had till then ever dreamt of removing from 
 the domain of water." 2 
 
 According to the Huttonian theory, fissures and 
 openings which have from time to time arisen in the 
 external crust of the earth have reached down to the 
 intensely hot nucleus. Up these rents the molten 
 material has ascended, forming veins of whinstone 
 underground, and, where it has reached the surface, 
 issuing there in the form of lava and the other 
 phenomena of volcanoes. Every geologist recognises 
 these generalisations as part of the familiar teachings 
 of modern geology. 
 
 We have seen that Werner made no distinction, 
 as regards origin, between what we now call mineral- 
 
 1 Cuvier, " liloge de De Saussure," Eloges, i. p. 427. 
 
 2 Cuvier, Op. cit. ii. p. 363. 
 
On Mineral Veins 309 
 
 veins and the dykes and veins of granite, basalt or 
 other eruptive rocks. He looked upon them all as 
 the results of chemical precipitation from an ocean 
 that covered the rocks in which fissures had been 
 formed. Hutton, in like manner, drew no line be- 
 tween the same two well-marked series of veins, but 
 regarded them all as formed by the introduction of 
 igneous material. Though more logical than Werner, 
 he was, as we now know, entirely in error in confound- 
 ing under one denomination two totally distinct assem- 
 blages of mineral matter. Werner correctly referred 
 veins of ores and spars to deposition from aqueous 
 solution, but was completely mistaken in attributing 
 the same origin to veins of massive rock. Hutton, 
 on the other hand, went as far astray in regard to 
 his explanation of mineral veins, but he made an 
 important contribution to science in his insistence upon 
 the truly intrusive nature of veins of granite and 
 whinstone. 
 
 There was another point of difference between the 
 views of Werner and of Hutton in regard to mineral 
 veins. One of the undoubted services of the Freiberg 
 professor was his clear demonstration than veins could 
 be classified according to their directions, that this 
 arrangement often sufficed to separate them also 
 according to age and material, those running along 
 one parallel, and containing one group of minerals, 
 being intersected by, and therefore older than, another 
 series following a different direction, and consisting of 
 other metals and vein-stones. This important dis- 
 tinction found no place in Hutton's system. To him 
 it was enough that he was able to show that certain 
 
310 James H^ltton 
 
 veins known to him were intrusive masses of igneous 
 origin. 1 
 
 In the Huttonian theory we find the germ of the 
 Lyellian doctrine of metamorphism. Hutton, having 
 demonstrated that granite is not an aqueous but an 
 igneous rock, further showed that the u Alpine schis- 
 tus," (which included sandstones, shales and slates, as 
 well as crystalline schists), being stratified, could not 
 be original or primitive, but had been deposited like 
 recent sediments, and had been invaded and altered 
 by the granite. A passage from his chapter, "On the 
 Primary Part of the Present Earth " may be quoted 
 in illustration of the sagacity of his judgment on this 
 subject : u If, in examining our land, we shall find a 
 mass of matter which had been evidently formed 
 originally in the ordinary manner of stratification, but 
 which is now extremely distorted in its structure and 
 displaced in its position, which is also extremely 
 consolidated in its mass and variously changed in its 
 composition, which, therefore, has the marks of its 
 original or marine composition extremely obliterated, 
 and many subsequent veins of melted mineral matter 
 interjected, we should then have reason to suppose 
 that here were masses of matter which, though not 
 different in their origin from those that are gradually 
 deposited at the bottom of the ocean, have been 
 more acted upon by subterranean heat and the ex- 
 
 1 In Playfair's Illustrations, however, the successive origin of mineral 
 veins is distinctly affirmed, 226. Reference is there made to the 
 coincidence between the prevalent direction of the principal Cornish 
 veins and the general strike of the strata, and to the intersection of 
 these by the cross-courses at nearly right angles. 
 
On the universality of Denudation 3 1 1 
 
 panding power, that is to say, have been changed in 
 a greater degree by the operations of the mineral king- 
 dom/' 1 Hutton here compresses into a single, though 
 somewhat cumbrous, sentence the doctrine to which 
 Lyell in later years gave the name of metamorphism. 
 Hutton's vision not only reached far back into the 
 geological past, it stretched into the illimitable future, 
 and it embraced also a marvellously broad yet minute 
 survey of the present. From his early youth he had 
 been struck with the evidence of incessant decay upon 
 the surface of the dry land. With admirable insight 
 he kept hold of this cardinal fact, and followed it 
 fearlessly from mountain-top to sea-shore. Wherever 
 we may go, on each variety of rock, in every kind 
 of climate, the doom of dissolution seemed to him to 
 be written in ineffaceable characters upon the whole 
 surface of the dry land. No sooner was the bed of 
 the ocean heaved up into mountains, than the new 
 terrestrial surface began to be attacked. Chemical 
 and mechanical agents were recognised as concerned 
 in this disintegration, though the precise nature and 
 extent of their several operations had not then been 
 studied. The general result produced by them, how- 
 ever, was never appreciated by any observer more 
 clearly than by Hutton. From the coast, worn into 
 stack and skerry and cave, by the ceaseless grinding 
 of the waves, he had followed the progress of cor- 
 rosion up to the crests of his Scottish hills. No 
 rock, even the hardest, could escape, though some 
 resisted more stubbornly than others. 
 
 1 Theory of the Earth, vol. i. pp. 375, 376. This passage may serve 
 also as an illustration of Hutton's peculiar style of composition. 
 
312 James Hutton 
 
 The universality of this terrestrial waste had been 
 more or less distinctly perceived by other writers, as 
 has been pointed out in previous pages. But Hutton 
 saw a meaning in it which no one before him had 
 so vividly realised. To his eye, while the whole land 
 undergoes loss, it is along certain lines traced by 
 running water that this loss reaches its greatest 
 amount. In the channels of the streams that carry 
 off the drainage of the land he recognised the results 
 of a constant erosion of the rocks by the water 
 flowing over them. As the generalisation was beauti- 
 fully expressed by Play fair : " Every river appears to 
 consist of a main trunk, fed from a variety of 
 branches, each running in a valley proportioned to 
 its size, and all of them together forming a system 
 of valleys, communicating with one another, and 
 having such a nice adjustment of their declivities, that 
 none of them join the principal valley, either on too 
 high or too low a level, a circumstance which would 
 be infinitely improbable if each of these valleys were 
 not the work of the stream that flows in it. 
 
 " If, indeed, a river consisted of a single stream 
 without branches, running in a straight valley, it 
 might be supposed that some great concussion, or 
 some powerful torrent, had opened at once the 
 channel by which its waters are conducted to the 
 ocean ; but, when the usual form of a river is con- 
 sidered, the trunk divided into many branches, which 
 rise at a great distance from one another, and these 
 again subdivided into an infinity of smaller ramifica- 
 tions, it becomes strongly impressed upon the mind 
 that all these channels have been cut by the waters 
 

 On excavation of Valleys 313 
 
 themselves ; that they have been slowly dug out by 
 the washing and erosion of the land ; and that it is 
 by the repeated touches of the same instrument that 
 this curious assemblage of lines has been engraved so 
 deeply on the surface of the globe." 1 
 
 The whole of the modern doctrine of earth- 
 sculpture is to be found in the Huttonian theory. 
 We shall better appreciate the sagacity and prescience 
 of Hutton and Playfair, if we remember that their 
 views on this subject were in their lifetime, and for 
 many years afterwards, ignored or explicitly rejected, 
 even by those who accepted the rest of their teaching. 
 Hall, their friend and associate, could not share their 
 opinions on this subject. Lyell too, who adopted so 
 much of the Huttonian theory and became the great 
 prophet of the Uniformitarian school, never would 
 admit the truth of Hutton's doctrine concerning the 
 origin of valleys. Nor even now is that doctrine uni- 
 versally accepted. It was Jukes who in 1862 revived 
 an interest in the subject, by showing how completely 
 the valley system in the south of Ireland was due to 
 the action of the rivers. 2 Ramsay soon after followed 
 with further illustrations of the principle. 3 Later 
 effective support to Hutton's teaching has been given 
 by the geologists of the United States, who, among 
 the comparatively undisturbed strata of the Western 
 
 ^ Illustrations of the Huttonian Theory, p. 102. It will be remembered 
 that the subaerial excavation of valleys was first demonstrated in ample 
 detail by Desmarest from Auvergne, and subsequently by De Saussure 
 from the Alps. The doctrine was afterwards sustained by Lamarck. 
 See chap. xi. 
 
 2 Quart. Journ. GeoL Soc. xviii. (1862). 
 
 Physical Geology and Geography of Great Britain , 1863. 
 
James Hut ton 
 
 Territories, have demonstrated, by proofs which the 
 most sceptical must accept, the potency of denudation 
 in the production of the topography of the land. 
 
 To the Huttonian school belongs also the con- 
 spicuous merit of having been the first to recognise 
 the potency of glaciers in the transport of detritus 
 from the mountains. Playfair, in his characteristically 
 brief and luminous way, proclaimed at the beginning of 
 last century that " for the removing of large masses 
 of rock the most powerful engines without doubt which 
 nature employs are the glaciers, those lakes or rivers 
 of ice which are formed in the highest valleys of the 
 Alps, and other mountains of the first order. . . . Be- 
 fore the valleys were cut out in the form they now 
 are, and when the mountains were still more elevated, 
 huge fragments of rock may have been carried to a 
 great distance ; and it is not wonderful if these same 
 masses, greatly diminished in size, and reduced to 
 gravel or sand, have reached the shores or even the 
 bottom of the ocean." 1 Here the conception of the 
 former greater extension of the glaciers was fore- 
 shadowed as a possible or even probable event in 
 geological history. Yet for half a century or more 
 after Playfair's time, men were still speculating on the 
 probability of the transport of the erratics by floating 
 icebergs during a submergence of Central Europe 
 under the sea, an hypothesis for which there was 
 not a particle of evidence. No geologist now ques- 
 tions the truth of Playfair's suggestion. 
 
 In the whole of Hutton's doctrine he rigorously 
 guarded himself against the admission of any principle 
 1 Illustrations, p. 388. 
 
On Continuity of Natures operations 3 1 5 
 
 which could not be founded on observation. He made 
 no assumptions. Every step in his deductions was 
 based upon actual fact, and the facts were so arranged 
 as to yield naturally and inevitably the conclusion 
 which he drew from them. Let me quote from the 
 conclusion of his work a few sentences in illustration of 
 these statements. In the interpretation of Nature, he 
 remarks, " no powers are to be employed that are not 
 natural to the globe, no action to be admitted of except 
 those of which we know the principle, and no extra- 
 ordinary events to be alleged in order to explain a 
 common appearance. The powers of Nature are not 
 to be employed in order to destroy the very object 
 of those powers ; we are not to make Nature act 
 in violation to that order which we actually observe, 
 and in subversion of that end which is to be perceived 
 in the system of created things. In whatever manner, 
 therefore, we are to employ the great agents, fire and 
 water, for producing those things which appear, it 
 ought to be in such a way as is consistent with the 
 propagation of plants and the life of animals upon 
 the surface of the earth. Chaos and confusion are 
 not to be introduced into the order of Nature, because 
 certain things appear to our practical views as being 
 in some disorder. Nor are we to proceed in feigning 
 causes when those seem insufficient which occur in our 
 experience." 1 
 
 No geologist ever lived among a more congenial 
 
 and helpful group of friends than Hutton. While 
 
 they had a profound respect for his genius, they were 
 
 drawn towards him by his winning personality, and 
 
 1 Theory of the Earth, vol. ii. p. 547. 
 
316 James Hittton 
 
 he became the centre of all that was bright, vivacious 
 and cheerful in that remarkable circle of eminent men. 
 If he wanted advice and assistance in chemical 
 questions, there was his bosom-friend Joseph Black, 
 ever ready to pour out his ample stores of knowledge, 
 and to test every proposition by the light of his wide 
 experience and his sober judgement. If he needed 
 companionship and assistance in his field journeys, 
 there was the sagacious Clerk of Eldin, willing to 
 join him, to examine his evidence with judicial 
 impartiality, and to sketch for him with an artistic 
 pencil the geological sections on which he laid most 
 stress. If he felt himself in need of the counsel of 
 a clear logical intellect, accustomed to consider physical 
 problems with the precision of a mathematician, there 
 was the kindly sympathetic Playfair, ever prompt and 
 pleased to do him a service. With such companions 
 he discussed his theory in all its bearings. Their 
 approval was ample enough for his ambition. He 
 was never tempted to court publicity by frequent 
 communications to learned societies, or the issue of 
 independent works treating of his geological observa- 
 tions and discoveries. But for the establishment of 
 the Royal Society of Edinburgh, he might have delayed 
 for years the preparation of the first sketch of his 
 theory, and had it not been for the virulent attacks 
 of Kirwan, he might never have been induced to 
 finish the preparation of his great work. He was a 
 man absorbed in the investigation of Nature, to whom 
 personal renown was a matter of utter indifference, 
 contented and happy in the warm regard and sym- 
 pathetic appreciation of the friends whom he loved. 
 
CHAPTER X 
 
 BIRTH of Experimental Geology. Sir James Hall. Decay of 
 Wernerianism. 
 
 AMONG the friends with whom Hutton associated 
 in Edinburgh there was one to whom allusion has 
 already been made, but who demands more special 
 notice here, seeing that to him a distinguished place 
 must be assigned among the founders of geology. 
 To Sir James Hall of Dunglass we owe the establish- 
 ment of experimental research as a powerful aid in 
 the investigation and solution of geological problems. 1 
 Inheriting a baronetcy and a landed estate in East 
 Lothian, not far from the picturesque cliffs of St. 
 Abb's Head, and possessed of ample leisure for the 
 prosecution of intellectual pursuits, he was led to 
 interest himself in geology. His father, a man of 
 scientific tastes, became acquainted with Hutton when 
 the future philosopher was a farmer in the neigh- 
 bouring county of Berwick. From these early days 
 Hutton found the hospitality of Dunglass always open 
 to him. It will be remembered that the famous 
 
 J The previous experiments of De Saussure have already been 
 referred to (ante p. 189) but they were not continued and led 
 to no satisfactory conclusions. 
 
3 1 8 Sir James Hall 
 
 visit to the rocks on the coast at Siccar Point, 
 described by Playfair, was made with Sir James from 
 that house. 
 
 At first Sir James Hall could not bring himself to 
 accept Hutton's views. " I was induced," he tells us, 
 "to reject his system entirely, and should probably 
 have continued still to do so, with the great majority of 
 the world, but for my habits of intimacy with the 
 author, the vivacity and perspicuity of whose conver- 
 sation formed a striking contrast to the obscurity of 
 his writings. I was induced by that charm, and by 
 the numerous original facts which his system had led 
 him to observe, to listen to his arguments in favour 
 of opinions which I then looked upon as visionary. 
 After three years of almost daily warfare with Dr. 
 Hutton on the subject of his theory, I began to view 
 his fundamental principles with less and less repug- 
 nance." 
 
 As his objections diminished, Hall's interest in the 
 details of the system increased. His practical mind 
 soon perceived that some of the principles, which 
 Hutton had established by reasoning and analogy, 
 might be brought to the test of direct experiment. 
 And he urged his friend to make the attempt, or allow 
 him to carry out the necessary researches. The proposal 
 received little encouragement from the philosopher. 
 Hutton believed that the scale of Nature's processes 
 was so vast that no imitation of them, on the small 
 scale of a laboratory, could possibly lead to any reliable 
 results, or as he afterwards expressed himself in print, 
 " there are superficial reasoning men who, without 
 1 Trans. Roy Soc. Edln. vi. (1812), pp. 71-186. 
 
His early Experiments 319 
 
 truly knowing what they see, think they know those 
 regions of the earth which can never be seen, and who 
 judge of the great operations of the mineral kingdom 
 from having kindled a fire and looked into the bottom 
 of a little crucible." 1 
 
 Sir James Hall, notwithstanding his veneration for 
 his master, could not agree with him in this verdict. 
 He was confirmed in his opinion by an accident which 
 had occurred at Leith glass-works, where a large mass 
 of common green glass, that had been allowed to 
 cool slowly, was found to have lost all the properties 
 of glass, becoming opaque, white, hard and crystalline. 
 Yet a piece of this substance, when once more melted 
 and rapidly cooled, recovered its true vitreous 
 characters. Hall's shrewd instinct at once applied this 
 observation to the Huttonian doctrine of the igneous 
 origin of granite and other rocks. It had been objected 
 to Hutton's views that the effect of great heat on 
 rocks was to reduce them to the condition of glass, 
 but that granite and whinstone, being crystalline 
 substances, could never possibly have been melted. 
 Yet here, in this glass-house material, it could be 
 demonstrated that a thoroughly molten glass could, 
 by slow cooling, be converted into a crystalline con- 
 dition, and could be changed once more by fusion 
 into glass. Hutton had overlooked the possibility 
 that the results of fusion might be modified by the 
 rate of cooling, and Hall at once began to test the 
 matter by experiment. He repeated the process by 
 which the devitrified glass had been accidentally ob- 
 tained at the glass-house, and found that he could 
 1 Theory of the Earth, vol. i. p. 251. 
 
320 Sir James Hall 
 
 at will produce, from the same mass of bottle glass, 
 either a glass or a stony substance, according to the 
 rate at which he allowed it to cool. 
 
 Sir James was too loyal a friend and too devoted 
 an admirer of the author of the Theory of the Earth 
 to pursue these researches far during the philosopher's 
 lifetime. " I considered myself as bound," he tells us, 
 u in practice to pay deference to his opinion, in a 
 field which he had already so nobly occupied, and I 
 abstained during the remainder of his life from the 
 prosecution of experiments which I had begun in 
 I790." 1 
 
 The death of Hutton in 1797 allowed the laird of 
 Dunglass to resume the experiments on which he had 
 been meditating during the intervening years. Select- 
 ing samples of u whinstones," that is, intrusive dole- 
 rites and basalts, from the dykes and sills in the 
 Carboniferous strata around Edinburgh, he reduced 
 them in the reverberatory furnace of an iron-foundry 
 to the condition of perfect glass. Portions of this 
 glass were afterwards re-fused and allowed to cool 
 very slowly. There was thus obtained " a substance 
 differing in all respects from glass, and in texture 
 completely resembling whinstone." This substance 
 had a distinctly crystalline structure, and Hall gave 
 it the name of crystallite, which had been suggested 
 by the chemist, Dr. Hope. 
 
 Before he was interested in the defence of the 
 Huttonian theory, Sir James had made a journey into 
 
 1 For Hall's papers see Trans. Roy. Soc. Edin. iii. (1790), p. 8 ; v. 
 (i79 8 )P-43; vi.(i8i2),p.7i ; vii.(i8i2),pp. 79, 139,169; 
 P- 3M- 
 
His discovery of Origin of Dykes 321 
 
 Italy in the year 1785, visiting Vesuvius, Etna, and 
 the Lipari Isles, and having for part of the time the 
 advantage of the company of Dolomieu. He could 
 not help being much struck with the resemblance 
 between the lavas of these volcanic regions and the 
 familiar " whinstones " of his own country. So close 
 was this resemblance in every respect that he felt 
 " confident that there was not a lava in Mount Etna 
 to which a counterpart might not be produced from 
 the whinstones of Scotland." At Monte Somma 
 he noted the abundant u vertical lavas " which, in 
 bands from two to twelve feet broad, run up the old 
 crater-wall. These bands seemed to him at the time 
 u to present only an amusing variety in the history 
 of volcanic eruptions," and, like Dolomieu and Breis- 
 lak, he looked on them as marking the positions of 
 rents which, formed in the mountain during former 
 volcanic explosions, had been filled in from above by 
 the outflow of lava down the outer fissured surface 
 of the cone. Subsequent reflection, however, led him 
 to reconsider this opinion, and to realise that these 
 " vertical lavas " were " of the utmost consequence in 
 geology, by supplying an intermediate link between 
 the external and subterraneous productions of heat. 
 I now think," he remarks, " that though we judged 
 rightly in believing those lavas to have flowed in 
 crevices, we were mistaken as to their direction ; for 
 instead of flowing downwards, I am convinced they 
 have flowed upwards, and that the crevices have 
 performed the office of pipes, through which lateral 
 explosions have found a vent." He had observed, 
 also, that the outer margins of some of these dykes, 
 
322 Sir James Hall 
 
 in contact with the surrounding rock, were vitreous, 
 while the central parts presented the ordinary lithoid 
 texture. This difference, he saw, was fully explained 
 by his fusion experiments. The lava having risen in a 
 cold fissure, and having been suddenly chilled along 
 its outer surface, consolidated there as glass, while 
 the inner parts, which had cooled more slowly, took 
 a crystalline structure. 
 
 These observations are of historic interest in the 
 progress of volcanic geology. Hall had sagaciously 
 found the true interpretation of volcanic dykes, and 
 he at once proceeded to apply it to the explanation 
 of the abundant dykes of Scotland. He thus brought 
 to the support of Hutton's doctrine of the igneous 
 intrusion of these rocks a new and strong confirma- 
 tion from the actual crater of a recent volcano. 
 
 When engaged upon his fusion experiments with 
 Scottish whinstones, it occurred to Hall to subject to 
 the same processes specimens of the lavas which he 
 had brought from Vesuvius and Etna. The results 
 which he thus obtained were precisely similar to those 
 which the rocks from Scotland had yielded. He was 
 able to demonstrate that lavas may be fused into a 
 perfect glass, and that this glass, on being re-melted 
 and allowed to cool gradually, passes into a stony 
 substance not unlike the original lava. In this 
 manner, the close agreement between modern lavas 
 and the ancient basalts of Scotland was clearly proved, 
 while their identity in chemical composition was 
 further shown by some analyses made by Dr. Robert 
 Kennedy. Sir James Hall had thus the satisfaction 
 of showing that a fresh appeal to direct experiment 
 
His experiments on Compression 323 
 
 and observation furnished further powerful support 
 to some of the disputed doctrines in the theory of 
 his old friend Hutton. 1 
 
 There was another and still more important direc- 
 tion in which it seemed to this original investigator 
 that the Huttonian doctrines might be subjected to 
 the test of experiment. It was an important feature 
 in these doctrines that the effects of heat upon rocks 
 must differ very much according to the pressure 
 under which the heat is applied. Hall argued, like 
 Hutton, that within the earth's crust the influence of 
 great compression must retard the fusion of mineral 
 substances, and retain within them ingredients which, 
 at the ordinary atmospheric pressure above ground, 
 are rapidly volatilized. He thus accounted for the 
 retention of carbonic acid by calcareous rocks, even at 
 such high temperatures as might melt them. Here 
 then was a wide but definite field for experiment, 
 and Hall entered it with the joy of a first pioneer. 
 As soon as he had done with his whinstone fusions, 
 he set to work to construct a set of apparatus that 
 would enable him to subject minerals and rocks to 
 the highest obtainable temperatures in hermetically 
 closed tubes. For six or seven years, he continued 
 his researches, conducting more than 500 ingeniously 
 devised experiments. He enclosed carbonate of lime 
 in firmly secured gun-barrels, in porcelain tubes, in 
 tubes bored through solid iron, and thereafter exposed 
 it to the highest temperatures which he could obtain. 
 
 1 " Experiments on Whinstone and Lava," read before the Royal 
 Society of Edinburgh 5th March and i8th June 1798, Trans. Roy. 
 Soc. Edin. vol. v. p. 43. 
 
324 Sir James Hall 
 
 He was able to fuse the carbonate without the loss 
 of its carbonic acid, thus practically demonstrating the 
 truth of Hutton's contention. He obtained from 
 pounded chalk a substance closely resembling marble. 
 Applying these results to the Huttonian theory, he 
 contended that the effects shown by his experiments 
 must occur also on a great scale at the roots of 
 volcanoes ; that subterranean lavas may melt lime- 
 stone ; that where the molten rock comes in contact 
 with shell-beds, it may either drive off their car- 
 bonic acid or convert them into limestone, according 
 to the heat of the lava and the depth under which 
 it acts ; and that his experiments enabled him to 
 pronounce under what conditions the one or the 
 other of these effects would be produced. He con- 
 cluded that having succeeded in fusing limestone 
 under pressure, he could adduce in that single result 
 " a strong presumption in favour of the solution 
 which Dr. Hutton has advanced of all the geological 
 phenomena ; for the truth of the most doubtful 
 principle which he has assumed has thus been estab- 
 lished by direct experiment." 1 
 
 Hardly less striking were Hall's experiments in 
 
 1 " Account of a series of experiments showing the effects of com- 
 pression in modifying the action of heat," read to the Royal 
 Society of Edinburgh, 3rd June 1805. Trans. Roy. Soc. Edin. vi. 
 p. 71. The same ingenious observer subsequently instituted a series 
 of experiments to imitate the consolidation of strata. By filling an 
 iron vessel with brine and having layers of sand at the bottom, he was 
 able to keep the lower portions of the sand at a red heat, while the 
 brine at the top was not too hot to let the hand be put into it. In 
 the end the sand at the bottom was found compacted into sandstone. 
 Op. at. x. (1825), p. 314. 
 
His experiments on Plication 325 
 
 illustration of the processes whereby strata, originally 
 horizontal, have been thrown into plications. His 
 machine for contorting layers of clay is familiar to 
 geological students from the illustrations of it given 
 in text-books. 1 He showed how closely the con- 
 volutions of the Silurian strata of the Berwickshire 
 coast could be experimentally imitated by the lateral 
 compression of layers of clay under considerable 
 vertical pressure. In this, as in his other applica- 
 tions of experiment, he led the way, and laid the 
 foundation on which later observers have built with 
 such success. 2 
 
 There was thus established at Edinburgh a group 
 of earnest and successful investigators of the history 
 of the earth, who promulgated a new philosophy of 
 geology, based upon close observation and carefully 
 devised experiment. Among these men there was 
 only one teacher the gentle and eloquent Playfair ; 
 but his functions at the University were to teach 
 mathematics and natural philosophy. He had thus 
 no opportunity of training a school of disciples who 
 
 1 Tram. Roy. Soc. Edm. vol. vii. p. 79 and Plate iv. As already 
 remarked, Hall differed from his master and from Playfair in regard 
 to their views on the efficacy of subaerial denudation. He preferred 
 to invoke gigantic debacles of water rushing over the land, and to 
 these he attributed the transport of large boulders and the smoothing 
 and striation of rocks, now referred to the action of glaciers 
 and ice-sheets. 
 
 2 The most illustrious of Hall's successors, A. Daubree, has made 
 generous recognition of the importance of the work of the early 
 master. Daubree's own studies in experimental geology are a monu- 
 ment of patient, skilful and original research, and well sustain the 
 high reputation of the French school of geologists. 
 
326 Robert Jameson 
 
 might be sent forth to combat the errors of the 
 dominant Wernerianism. He did what he could in 
 that direction by preparing and publishing his admir- 
 able " Illustrations/' which were widely read, and, as 
 Hall has recorded, exerted a powerful influence on 
 the minds of the most eminent men of science of 
 the day. 
 
 But another influence, strongly antagonistic to the 
 progress of the Huttonian philosophy, was established 
 in Edinburgh at the very time when the prospect 
 seemed so fair for the creation of a Scottish school 
 which might do much to further the advance of 
 sound geology. Robert Jameson (1774-1854), whose 
 influence and writings have been referred to in Chap- 
 ter VIII., had studied for nearly two years at 
 Freiberg under Werner. After two more years spent 
 in continental travel, full of enthusiasm for his 
 master's system, he had returned to the Scottish 
 capital in 1804, when he was elected to the Chair 
 of Natural History in the University. His genial 
 personal character, and his zeal for the Freiberg faith 
 soon gathered a band of ardent followers around 
 him. He had much of Werner's power of fostering 
 in others a love of the subjects that interested him- 
 self. Travelling widely over Scotland, from the 
 southern borders to the furthest Shetland Isles, he 
 everywhere saw the rocks through Saxon spectacles. 
 From the very beginning, the books and papers 
 which he wrote were drawn up after the most ap- 
 proved Wernerian method, pervaded by the amplest 
 confidence in that method, and by hardly disguised 
 contempt for every other. Nowhere indeed can the 
 
The Wernerian Natural History Society 3 27 
 
 peculiarities of the Wernerian style be seen in more 
 typical perfection than in the writings of the Edin- 
 burgh professor. 1 
 
 In the year 1808, Jameson founded a new scientific 
 association in Edinburgh, which he called the a Wer- 
 nerian Natural History Society," with the great 
 Werner himself at the head of its list of honorary 
 members. So far as geology was concerned, the 
 original aim of this institution appears to have been 
 to spread the doctrines of Freiberg. I know no 
 more melancholy contrast in geological literature than 
 is presented when we pass from the glowing pages 
 of Playfair, or the suggestive papers of Hall, to 
 the dreary geognostical communications in the first 
 published Memoirs of this Wernerian Society. On 
 the one side, we breathe the spirit of the most 
 enlightened modern geological philosophy, on the 
 other we grope in the darkness of a Saxon mine, 
 and listen to the repetition of the familiar shibbo- 
 leths, which even the more illustrious of Werner's 
 disciples were elsewhere beginning to discard. 
 
 The importation of the Freiberg doctrines into Scot- 
 land by an actual pupil of Werner, carried with it the 
 controversy as to the origin of basalt. This question, 
 it might have been thought, had been practically 
 settled there by the writings of Hutton, Playfair, and 
 Hall, even if it had not been completely solved by 
 
 1 See, for instance, the way in which he dismisses the observations 
 of Faujas de St. Fond on Scottish rocks, and the unhesitating declara- 
 tion that there is not in all Scotland the vestige of a volcano. 
 Mineralogy of the Scottish Isles (1800), p. 5. He never loses an oppor- 
 tunity of a sneer at the " Vulcanists " and " fire-philosophers." 
 
328 Robert Jameson 
 
 Desmarest, Von Buch, D'Aubuisson, and others on 
 the Continent. But the advent of Jameson rekindled 
 the old fires of controversy. The sections of the rocks 
 laid open among the hills and ravines around Edin- 
 burgh, which display such admirable illustrations of 
 eruptive action, were confidently appealed to alike by 
 the Plutonists and the Neptunists. Jameson carried 
 his students to Salisbury Crags and Arthur Seat, and 
 there demonstrated to them that the so-called igneous 
 rocks were manifestly merely chemical precipitates in 
 the " Independent Coal formation." The Huttonians 
 were ready to conduct any interested stranger to the 
 very same sections to prove that the whinstone was 
 an igneous intrusion. There is a characteristic anec- 
 dote told of one of these excursions in an article 
 by Dr. W. H. Fitton in the Edinburgh Review. One 
 of the Irish upholders of the aqueous origin of basalt, 
 Dr. Richardson, had attained some notoriety from 
 having found fossils in what he called basalt at Port- 
 rush, on the coast of Antrim. His discovery was 
 eagerly quoted by those who maintained the aqueous 
 origin of that rock, and though eventually Playfair 
 showed that the fossils really lie in Lias shale, which 
 has been baked into a flinty condition by an intrusive 
 basaltic sheet, this explanation was not accepted by the 
 other side, and the fossiliferous basalt of Antrim con- 
 tinued to be cited as an indubitable fact by the zealous 
 partizans of Werner. While these were still matters 
 of controversy Dr. Richardson paid a visit to Scot- 
 land, chiefly with reference to fiorin grass, in which he 
 was interested. The writer in the Edinburgh Review 
 tells us that he was asked by Sir James Hall, to meet 
 
Irish opponents of Hut ton 329 
 
 Dr. Hope and the Irish geologist. " It was arranged 
 that the party should go to Salisbury Crags, to show 
 Dr. Richardson a junction of the sandstone with the 
 trap, which was regarded as an instructive example 
 of that class of facts. After reaching the spot, Sir 
 James pointed out the great disturbance that had taken 
 place at the junction, and particularly called the atten- 
 tion of the doctor to a piece of sandstone which had 
 been whirled up during the convulsion and enclosed 
 in the trap. When Sir James had finished his lecture, 
 the doctor did not attempt to explain the facts before 
 him on any principle of his own, nor did he recur 
 to the shallow evasion of regarding the enclosed sand- 
 stone as contemporaneous with the trap ; but he burst 
 out into the strongest expressions of contemptuous 
 surprise that a theory of the earth should be founded 
 on such small and trivial appearances ! He had been 
 accustomed, he said, to look at Nature in her grandest 
 aspects, and to trace her hand in the gigantic cliffs 
 of the Irish coast ; and he could not conceive how 
 opinions thus formed could be shaken by such minute 
 irregularities as those which had been shown to him. 
 The two Huttonian philosophers were confounded ; 
 and, if we recollect rightly, the weight of an acre of 
 fiorin and the number of bullocks it would feed formed 
 the remaining subjects of conversation." 1 
 
 It is not needful to follow into further detail the 
 history of the opposition encountered by the Huttonian 
 theory of the earth. Some of the bitterest antagonists 
 of Hutton hailed from Ireland. Besides Richardson, 
 with his fossiliferous basalt, there was Kirwan, President 
 
 1 Edinburgh Review, No. Ixv. 1837, p. 9. 
 
33 Decay of IVernerianism at Edinburgh 
 
 of the Royal Irish Academy, whose ungenerous attacks 
 stung Hutton into the preparation of his larger treatise. 
 In England and on the Continent another determined 
 opponent was found in the versatile and prolific De 
 Luc. But though these men wielded great influence 
 in their day, their writings have fallen into deserved 
 oblivion. They are never read save by the curious 
 student, who has leisure and inclination to dig among 
 the cemeteries of geological literature. 
 
 The gradual progress of the Huttonian school and 
 the concomitant decay of Wernerianism at Edinburgh, 
 are well indicated by the eight volumes of Memoirs 
 published by Jameson's Wernerian Society, which 
 ranged from 1811 to 1839, an interval of less than a 
 generation. The early numbers might have emanated 
 from Freiberg itself. Not a sentiment is to be found 
 in them of which Werner himself would not have 
 approved. How heartily, for example, Jameson must 
 have welcomed the concluding sentence of a paper 
 by one of the ablest of his associates when, after a not 
 very complimentary allusion to Hutton's views about 
 central heat, the remark is made u He who has the 
 boldness to build a theory of the earth without a know- 
 ledge of the natural history of rocks, will daily meet 
 with facts to puzzle and mortify him." 1 The fate 
 which this complacent Wernerian here predicted for 
 the followers of Hutton, was now surely and steadily 
 overtaking his own brethren. One by one the faithful 
 began to fail, and, as we have seen, those who had 
 gone out to preach the faith of Freiberg came back 
 
 !The Rev. John Fleming, Mem. Wer. Soc. vol. ii. (1813), 
 p. 154. 
 
Defection of Jameson's Pupils 331 
 
 convinced of its errors, and of the truth of much which 
 they had held up to scorn in the tenets of the Plu- 
 tonists. Even among Jameson's own students, as 
 already noticed (ante, pp. 241, 263), defections began to 
 appear in the early decades of last century. His friends 
 might translate into English, and publish at Edinburgh, 
 tracts of the most orthodox Wernerianism, such as 
 Werner's Treatise on Veins , or Von Buch's Description 
 of Landeck, or D' Aubuisson's Basalts of Saxony. But his 
 pupils, who went farther afield, who came into contact 
 with the distinct current of opposition to some of the 
 doctrines of the Freiberg school that was now setting 
 in on the Continent, who began seriously to study the 
 igneous rocks of the earth's crust, and who found at 
 every turn facts that could not be fitted into the system 
 of Freiberg, gradually, though often very reluctantly, 
 went over to the opposite camp. Men like Ami Boue 
 would send to Jameson notes of their travels, full of 
 what a staunch Wernerian could not but regard as the 
 rankest heresy. 1 But the Professor with great impar- 
 tiality printed these in the Society's publications. And 
 so by degrees the Memoirs of the Wernerian Society 
 ceased to bear any trace of Wernerianism, and con- 
 tained papers of which any Huttonian might have been 
 proud to be the author. 2 
 
 One important result of the keen controversies 
 
 1 See Mem. Wer. Soc. vol. iv. (1822), p. 91. 
 
 2 See, for example, the papers by Hay Cunningham in vols. vii. 
 and viii. In an Address to the Geological Society in 1828 Fitton 
 alluded to the universal adoption in Britain of " a modified volcanic 
 theory, and the complete subsidence, or almost oblivion of the 
 Wernerian and Neptunian hypotheses." Proc. Geol. Soc. i. p. 55. 
 
33 2 Decay of mere Theorizing 
 
 between the Vulcanist and Neptunist schools in Europe 
 is to be found in the appeal that was necessitated to 
 Nature herself for a solution of the disputed problems. 
 The days of mere theorizing in the cabinet or the 
 study had now passed away. Everywhere there was 
 aroused a spirit of inquiry into the evidence furnished 
 by the earth itself as to its history. The main theo- 
 retical principles of the science had been established, so 
 far as related to geological processes and their influence 
 in the structure of the terrestrial crust. But the 
 palaeontological side of geology had still to be opened 
 up. The fruitful doctrine of stratigraphy remained 
 to be developed and applied to the elucidation of the 
 grand record of geological history. How this doctrine, 
 which has done more than any other for the progress 
 of geological investigation, was worked out will be the 
 subject of the next four chapters. 
 
CHAPTER XI 
 
 THE Rise of Stratigraphical Geology and of Palaeontology Giraud- 
 Soulavie, Lamarck, Cuvier, Brongniart, and Omalius d'Halloy 
 in France. 
 
 THAT the rocks around and beneath us contain the 
 record of terrestrial revolutions before the establish- 
 ment of the present dry land, was an idea clearly 
 present to the minds of the early Italian geologists, 
 and, having been so eloquently enforced by Buffon, 
 was generally admitted, before the end of the 
 eighteenth century, by all who interested themselves 
 in minerals and rocks. The Neptunists and Vulcan- 
 ists might dispute vigorously over their respective 
 creeds, but they all agreed in maintaining the doctrine 
 of a geological succession. Werner made this doctrine 
 a cardinal part of his system, and brought it into 
 greater prominence than it had ever held before his 
 time. His sequence of formations from granite, at 
 the base, to the youngest river-gravel or sea-formed 
 silt, betokened, in his view, a gradual development of 
 deposits, which began with the chemical precipitates 
 of a universal ocean, and ended with the modern 
 mechanical and other accumulations of terrestrial sur- 
 faces, as well as of the sea-floor. But, as we have 
 
334 The Doctrine of Geological Succession 
 
 seen, the lithological characters on which he based 
 the discrimination of his various formations proved 
 to be unreliable. Granite was soon found not always 
 to lie at the bottom. Basalt, at first placed by him 
 among the oldest formations, turned up incontinently 
 among the youngest. He and his disciples were 
 consequently obliged to alter and patch the Freiberg 
 system, till it lost its simplicity and self-consistence, 
 and was still as far as ever from corresponding with 
 the complex order which nature had followed. Ob- 
 viously the Wernerian school had not found the key 
 to the problem, though it had done service in 
 showing how far a lithological sequence could be 
 traced among the oldest rocks. 
 
 Hutton's views on this question were in some 
 respects even less advanced than Werner's. He 
 realized, as no one had ever done so clearly before 
 him, the evidence for the universal decay of the land. 
 At the same time, he perceived that unless some 
 compensating agency came into play, the whole of 
 the dry land must eventually be washed into the sea. 
 The upturned condition of the Primary strata, which 
 had once been formed under the sea, furnished him 
 with proofs that in past time the sea-floor has been 
 upheaved into land. Without invoking any fanciful 
 theory, he planted his feet firmly on these two classes 
 of facts, which could be fully demonstrated. To his 
 mind the earth revealed no trace of a beginning, no 
 prospect of an end. All that he could see was the 
 evidence of a succession of degradations and up- 
 heavals, by which the balance of sea and land and 
 the habitable condition of our globe were perpetuated. 
 
Recognition of the importance of Fossils 335 
 
 Hutton was unable to say how many of these revo- 
 lutions may be chronicled among the rocks of the 
 earth's crust 1 Nor did he discover any method by 
 which their general sequence over the whole globe 
 could be determined. 
 
 A totally new pathway of investigation had now to 
 be opened up. The part that had hitherto been 
 played by species of minerals and rocks was hence- 
 forth to be taken by species of plants and animals. 
 Organic remains, imbedded in the strata of the earth's 
 crust, had been abundantly appealed to as evidence 
 of the former presence of the sea upon the land, 
 or as proofs of upheaval of the sea-floor. But they 
 were now to receive far closer attention, until they 
 were found to contain the key to geological history, 
 to furnish a basis by which the past revolutions of 
 the globe could be chronologically arranged and 
 accurately described, and to cast a flood of light 
 upon the history and development of organised life 
 upon the surface of the earth. 
 
 Apart altogether from questions of cosmogony or 
 of geological theory, some of the broad facts of 
 stratigraphy could not but, at an early time, attract 
 attention. In regions of little-disturbed sedimentary 
 rocks, the superposition of distinct strata, one upon 
 another, was too obvious to escape notice. A little 
 travel with observant eyes would enable men to see 
 that the same kinds of strata, accompanied by the 
 
 1 Playfair thought that the revolutions may have been often 
 repeated, and that our present continents appear to be the third 
 in succession, of which relics may be observed among the rocks. 
 Works, vol. iv. p. 55. 
 
336 Lister's observations on Fossils 
 
 same topographical characters, ranged from district 
 to district, across wide regions. We have found that 
 it was in countries of regular and gently-inclined 
 stratified rocks that Lehmann and Fttchsel made their 
 observations, which paved the way for the develop- 
 ment of the idea of palaeontological succession. We 
 have now to trace the growth of this idea, and the 
 discovery that organic remains furnish the clue to the 
 relative chronology of the strata in which they are 
 imbedded. 
 
 The fact that different rocks contain dissimilar but 
 distinctive fossils had been noted by various observers 
 long before its geological significance was perceived. 
 Thus, as far back as 1671, we find Martin Lister 
 affirming, in a letter already cited (p. 76), that "quarries 
 of different stone yield us quite different sorts or species 
 of shells not only one from another (as those Cockle- 
 stones of the iron-stone quarries of Adderton, in 
 Yorkshire, differ from those found in the lead-mines 
 of the neighbouring mountains, and both these from 
 the cockle-quarrie of Wansford Bridge, in North- 
 amptonshire ; and all three from those to be found 
 in the quarries about Gunthrop and Beauvour Castle, 
 etc.), but, I dare boldly say, from anything in nature 
 besides, that either the land, salt or freshwater doth 
 yield us." 1 
 
 Again, John Strange writing in 1779 remarks that 
 
 1 Phil. Trans, vol. vi. p. 2283. Greenough in his Critical Ex- 
 amination of the First Principles of Geology, 1819, (p. 284), in quoting 
 this passage, adds that Lister had " followed the course of the Chalk 
 Marl over an extensive tract of country by mere attention to its 
 fossils," but no reference is given to the authority for this statement. 
 
Strangers tracing of Lias Outcrop 337 
 
 " the Gryphites oyster is not only found abundantly in 
 the lower part of Monmouthshire and about Purton 
 Passage, but also extends in considerable aggregates 
 along the neighbouring midland counties ; having 
 myself traced them, either in gravel or limestone, 
 through Gloucestershire, Worcestershire, Warwick- 
 shire and Leicestershire, occupying in like manner 
 the lower parts of those counties, under the hills." 1 
 It would thus appear that the outcrop of the Lias 
 had been traced, by means of its fossils, across a 
 great part of England some years before William 
 Smith began his labours. 
 
 There were two regions of Europe well fitted to 
 furnish any competent inquirers with the evidence for 
 establishing, by means of fossil organic remains, this 
 supremely important section of modern geology. In 
 France, the Secondary and Tertiary formations lie in 
 undisturbed succession, one above another, over 
 hundreds of square miles. They come to the surface, 
 not obscured under superficial deposits, but projecting 
 their escarpments to the day, and showing, by their 
 topographical contours, the sharply defined limits of 
 their several groups. Again, in England, the same 
 formations cover the southern and eastern parts of 
 the country, displaying everywhere the same clear 
 evidence of their arrangement. Let us trace the 
 progress of discovery in each of these regions. To a 
 large extent this progress was simultaneous, but there 
 is no evidence that the earlier workers in the one 
 country were aware of what was being done in the 
 other. 
 
 1 Archaeokgidj vol. vi. (1782), p. 36. 
 
 Y 
 
338 Giraud-Soulame 
 
 To the Abbe J. L. Giraud-Soulavie (1752-1813) 
 the merit must be assigned of having planted the first 
 seeds from which the magnificent growth of strati- 
 graphical geology in France has sprung. Among 
 other works, he wrote a Natural History of Southern 
 France in seven volumes, of which the first two 
 appeared in the year 1780. He gave much of his 
 attention to the old volcanoes of his native country, 
 and devoted several of his volumes entirely to their 
 description. But his chief claim to notice here lies 
 in a particular chapter of his work which, he tells us, 
 was read before the Royal Academy of Sciences of 
 Paris on I4th August I779- 1 In describing the cal- 
 careous mountains of the Vivarais, he divided the 
 limestones into five epochs or ages, the strata in each 
 of which are marked by a distinct assemblage of 
 fossil shells. The first of these ages, he declared, 
 was represented by limestone containing organic 
 remains with no living analogues, such as ammonites, 
 belemnites, terebratulae, gryphites, etc. Having no 
 more ancient strata in the district, the Abbe called 
 this oldest limestone primordial. His second age 
 was indicated by limestone, in which the fossils of 
 the preceding epoch were still found, but associated 
 with some others now living in our seas. Among the 
 new forms of life that appeared in these secondary 
 strata he enumerated chamas, mussels, comb-shells, 
 nautili, etc. These, he said, inhabited the sea, to- 
 gether with survivors from the first age, but the 
 latter at the end of the second age disappeared. 
 
 1 Histoire Naturelle de la France Meridionale, tome i. 2 me partie, 
 chap. viii. p. 317. 
 
His "Five Ages" in the Vivarais 339 
 
 Above their remains other races established them- 
 selves, and carried on the succession of organised 
 beings. 
 
 The third age was one in which the shells were of 
 recent forms, with descendants that inhabit the present 
 seas. The remains of these shells were found in a 
 soft white limestone, but not a trace of ammonite, 
 belemnite, or gryphite was to be seen associated with 
 them. Among the organisms named by the Abb 
 were limpets, whelks, volutes, oysters, sea-urchins, 
 and others, the number of species increasing with the 
 comparative recentness of the formation. He thought, 
 like Werner, that the most ancient deposits had been 
 accumulated at the highest levels, when the sea covered 
 the whole region, and that, as the waters sank, 
 successively younger formations were laid down at 
 lower and lower levels. 
 
 From the occurrence of worn pebbles of basalt in 
 the third limestone, Giraud-Soulavie inferred that vol- 
 canic eruptions had preceded that formation, and that 
 an enormous duration of time was indicated by the 
 erosion of the lavas of these volcanoes, and the 
 transport and deposit of their detritus in the white 
 limestone. 
 
 The fourth age in the Vivarais was represented by 
 certain carbonaceous shales or slates, containing the 
 remains of primordial vegetation to which it was 
 difficult to discover the modern analogues. Giraud- 
 Soulavie believed that he could observe among these 
 slates a succession of organic remains similar to that 
 displayed by the limestones, those strata which lay on 
 the oldest marble containing ammonites, while the 
 
34 Giraud-Soulavie 
 
 most recent enclosed, but only rarely, unknown plants 
 mingled with known forms. It would thus appear 
 that the deposits of the so-called fourth age were 
 more or less equivalents of those of the three cal- 
 careous ages. 
 
 The fifth age was characterised by deposits of 
 conglomerate and modern alluvium, containing fossil 
 trees, together with bones and teeth of elephants and 
 other animals. " Such is the general picture," the 
 Abbe remarks, " presented by our old hills of the 
 Vivarais, and of the modern plains around them. 
 The progress of time and, above all, of increased 
 observation will augment the number of epochs which 
 I have given, and fill up the blanks ; but they will 
 not change the relative places which 1 have assigned to 
 these epochs." * He felt confident that if the facts 
 observed by him in the Vivarais were confirmed in 
 other regions, a historical chronology of fossil and 
 living organisms would be established on a basis of 
 incontestible truth. In his last volume, replying to 
 some objections made to his opinions regarding the 
 succession of animals in time, he contends that the 
 difference between the fossils of different countries is 
 due not to a geographical but to a chronological cause. 
 " The sea," he says, " produces no more ammonites, 
 because these shells belong to older periods or other 
 climates. The difference between the shells in the 
 rocks rests on the difference in their relative antiquity, 
 and not on mere local causes. If an earthquake were 
 to submerge the ammonite -bearing rocks of the 
 Vivarais beneath the Mediterranean, the sea returning 
 1 Op. dt. p. 350. 
 
Sagacity of his generalisations 341 
 
 to its old site would not bring back its old shells. 
 The course of time has destroyed the species, and 
 they are no longer to be found in the more recent 
 rocks." i 
 
 The sagacity of these views will at once be acknow- 
 ledged. Yet they seem to have made, for a time, 
 no way either in France or elsewhere. The worthy 
 Abbe, though a good observer and a logical reasoner, 
 was a singularly bad writer. At the end of the 
 eighteenth century a wretched style was an unpardon- 
 able offence even in a man of science. 2 Whatever 
 may have been the cause, Giraud-Soulavie has fallen 
 into the background. His fame has been eclipsed, 
 even in France, by the more brilliant work of his 
 successors. Yet, in any general survey of geological 
 progress, it is only just to acknowledge how firmly 
 he had grasped some of the fundamental truths of 
 stratigraphical geology, at a time when the barren 
 controversy about the origin of basalt was the main 
 topic of geological discussion throughout Europe. 
 
 We have seen that the distinctness, regularity, and 
 persistence of the outcrops of the various geological 
 formations of the Paris basin suggested to Guettard 
 the first idea of depicting on maps the geographical 
 distribution of rocks and minerals. The same region 
 and the same features of topography and structure 
 inspired long afterwards a series of researches that 
 contributed in large measure to the establishment of 
 the principles of geological stratigraphy. No fitter 
 birthplace could be found in Europe for the rise of 
 
 1 Op. cit. tome vii. (1784), p. 157. 
 
 2 D'Archiac, Geologic et Pa/eon fotogie, 1866, p. 145. 
 
34 2 G. P. Rouelle 
 
 this great department of science. Around the capital 
 of France, the Tertiary and Secondary formations are 
 ranged in orderly sequence, group emerging from 
 under group, to the far confines of Brittany on the 
 west, the hills of the Ardennes and the Vosges on 
 the east, and the central plateau on the south. Not 
 only is the succession of the strata clear, but their 
 abundant fossils furnish a most complete basis for 
 stratigraphical arrangement and comparison. 
 
 Various observers had been struck with the orderly 
 sequence of rocks in this classic region. Desmarest 
 tells us that the chemist G. F. Rouelle (1703-1770) 
 was so impressed with its symmetry of structure that, 
 though he never wrote anything on the subject, he 
 used to discourse on it to his students at the Jardin 
 des Plantes, of whom Desmarest himself appears to 
 have been one. He would enlarge to them upon the 
 significance of the masses of shells imbedded in the 
 rocks of the earth's surface, pointing out that these 
 rocks were not disposed at random, as had been 
 supposed. He saw that the shells were not the 
 same in all regions, that certain forms were always 
 found associated together, while others were never 
 to be met with in the same strata or layers. He 
 noticed, as Guettard had done before him, that in 
 some districts the fossil shells were grouped in exactly 
 the same kind of arrangement and distribution as on 
 the floor of the present sea a fact which, in his 
 eyes, disproved the notion that these marine organisms 
 had been brought together by some violent deluge ; 
 but which, on the other hand, showed that the present 
 land had once been the bottom of the sea, and had been 
 
Researches in the Paris Basin 343 
 
 laid dry by some revolution that took place without 
 producing any disturbance of the strata. Rouelle 
 recognised a constant order in the arrangement of the 
 shells. Thus, immediately around Paris, he found 
 certain strata to be full of screw shells (Turritella, 
 Cerithium, etc.), and to extend to Chaumont, on the 
 one side, and to Courtagnon near Rheims, on the other. 
 He pointed to a second deposit, or u mass " as he 
 called it, full of belemnites, ammonites, gryphites, 
 etc. (Jurassic), forming a long and broad band out- 
 side the eastern border of the Chalk, and stretching 
 north and south beyond that formation up to the old 
 rocks of the Morvan. Desmarest's account of his 
 teacher's opinions was published in the third year of 
 the Republic. 1 It is thus evident that Rouelle had 
 formed remarkably correct views of the general strati- 
 graphy of the Paris basin probably long before 1794. 
 Desmarest himself published many valuable observa- 
 tions regarding the rocks of the Paris basin in separate 
 articles in his great Geographic Physique. Lamanon had 
 written on the gypsum deposits of the region, which 
 he regarded as marking the sites of former lakes, 
 and from which he described and figured the remains 
 of mammals, birds and fishes. Noting the alterna- 
 tions of gypsum and marls, he traced what he 
 believed to be the limits of the sheets of freshwater 
 in which they were successively deposited. Still more 
 precise was the grouping adopted by Lavoisier (1743- 
 1794). This great man, who, if he had not given 
 himself up to chemistry, might have become one of 
 
 ^Geographic Physique (Encyclopedic Methodiqui)^ tome i. (1794), 
 pp. 409-431. 
 
344 Lavoisier as Geologist 
 
 the most illustrious among the founders of geology, 
 was, as already stated (p. 1 1 5), associated early in life 
 with Guettard in the construction of mineralogical 
 maps of France. As far back as the year 1789, he 
 distinguished between what he called littoral banks and 
 pelagic banks, which were formed at different distances 
 from the land, and were marked by distinct kinds 
 of sediment and peculiar organisms. He thought 
 that the different strata, in such a basin as that of 
 the Seine, pointed to very slow oscillations of the 
 level of the sea, and he believed that a section of 
 all the stratified deposits between the coasts and the 
 mountains would furnish an alternation of littoral 
 and pelagic banks, and would reveal by the number 
 of strata the number of excursions made by the waters 
 of the ocean. Lavoisier accompanied his essay with 
 sections which gave the first outline of a correct 
 classification of the Tertiary deposits of the Paris 
 region. His sketch was imperfect, but it represented 
 in their true sequence the white Chalk supporting 
 the Plastic Clay, lower sands, Calcaire Grossier, upper 
 sands and upper lacustrine limestone. 1 
 
 A few years later, a more perfect classification of 
 these Tertiary deposits was published by Coupe, but 
 without sufficiently detailed observations to convince 
 his contemporaries that the work was wholly reliable. 2 
 
 1 Mem. Acad. Roy. Sciences (1789), p. 350, pi. 7. This memoir 
 of Lavoisier on modern horizontal strata and their disposition 
 is fully noticed by Desmarest in the first volume of his Geographic 
 Physique, p. 783. Lavoisier's distinction between pelagic and 
 littoral organisms and deposits was afterwards adopted by Lamarck 
 (postea, p. 355). 
 
 2 Journ. de Physique, tome lix. (1804), pp. 161-176. 
 
Lamarck's Biography 345 
 
 The Tertiary formations of the great basin of 
 the Seine were destined not only to furnish a vast 
 impetus to the development of stratigraphical geology, 
 but to provide the first broad scientific basis for the 
 foundation of the science of Palaeontology. In this 
 momentous development of geological science two 
 names stand out with conspicuous prominence among 
 those who carried on the work Lamarck and Cuvier. 
 
 Jean-Baptiste-Pierre-Antoine de Monet, Chevalier 
 de Lamarck (1744-1829) came of an ancient but 
 somewhat decayed family, and was born in a village 
 of Picardy, as the eleventh and youngest child of 
 the Seigneur de Beam. 1 The ancestral patrimony 
 having become too slender to provide a living for 
 the boy, he was designed for the church, and was 
 sent to begin his studies under the Jesuits of Amiens. 
 But since for centuries his ancestors had been soldiers, 
 and he had three brothers in the army, he could not 
 bring himself to settle down finally to the peaceful 
 life of an ecclesiastic. The death of his father in 
 1760 gave him an opportunity of leaving his books 
 and joining the French forces that were then engaged 
 in the disastrous war which began in 1756. With no 
 other passport than a letter of introduction from a 
 lady in his neighbourhood to the Colonel of the 
 Beaujolais regiment, he set out for the seat of war, 
 mounted on a sorry nag, and attended by a poor 
 
 1 For the biographical details of Lamarck's life I am indebted 
 to Cuvier's Eloge of him in the Recueil des Eloges Historiques, 
 vol. iii. p. 179, and to the excellent volume by Mr. A. S. 
 Packard, Lamarck, the Founder of Evolution: His Life and Work, 
 1901. 
 
346 Lamarck 
 
 lad of his village. He arrived at the camp immedi- 
 ately before an attack was to be made on the allied 
 army under Prince Ferdinand of Brunswick. 
 
 In this attack, known as the battle of Willingshausen 
 (i4th July 1761), which ended in the signal defeat 
 of the French, young Lamarck at last found himself 
 in charge of his company, whereof all the officers had 
 been killed in the action, and which was left behind 
 unnoticed in the confusion of the retreat. The oldest 
 grenadier of the band counselled him to retire, but 
 the youthful volunteer, with characteristic courage, 
 refused to move without orders from the post that 
 had been assigned to them. Not without some risk 
 and difficulty he and the remnant of his company 
 were at last relieved and withdrawn. He was at 
 once rewarded for his valour by being made an 
 officer by the Commander-in-Chief. Further pro- 
 motion followed, and after the peace he passed some 
 time in garrison duty. The enforced leisure of this 
 kind of life, and the seclusion rendered necessary by 
 a severe accident, led him to return to some of the 
 studies, more particularly to botany, which had inter- 
 ested him during his stay at the College. 
 
 Seeing at last no prospect of a satisfactory future 
 in the army he resolved to try his fortune elsewhere, 
 and to qualify himself for the medical profession. 
 Having, however, an annual allowance of no more 
 than 400 francs, he eked out his slender income by 
 working for a portion of his time in the office of a 
 banker. His medical education is said to have 
 extended over four years. But he does not seem 
 ever to have taken up the practice of the profession, 
 
His first scientific Paper 347 
 
 though the scientific training he then received must 
 have been an excellent prelude to his subsequent 
 career. 
 
 Lamarck, from his early love for plants, threw 
 himself with all the ardour of his enthusiastic and 
 indomitable nature into the study of botany, inso- 
 much that at the age of 24 he abandoned everything 
 else to be able to devote himself to its pursuit. He 
 worked under Bernard de Jussieu at the Jardin des 
 Plantes, and made botanical excursions round Paris 
 with Rousseau. He was eventually appointed Keeper 
 of the Herbarium of the Royal Gardens at the miser- 
 able salary of 1000 francs, afterwards increased to 
 1800. Yet his first published essay showed that he 
 was not entirely engrossed in botanical studies. Not 
 improbably the high garret in the Quartier Latin, 
 which he had tenanted as a student, and which com- 
 manded a wide view of the sky, had given him 
 occasion to watch the movements of the clouds and 
 other phenomena of meteorology. At all events, 
 in the year 1776, when he was 32 years of age, he 
 presented to the Academy of Sciences a memoir 
 " On the Vapours of the Atmosphere," which was well 
 received, and proved to be the first of a long series of 
 contributions from him to meteorological science. 
 
 After ten years of earnest botanical study Lamarck 
 published in 1778 his Flore Franfaise in three volumes. 
 In this work he gave a succinct description of all 
 the wild plants of the country, arranged in accord- 
 ance, not with the Linnaean system of nomenclature, 
 but with a classification which he had himself devised. 
 This treatise, at the special instance of BufFon, was 
 
348 Lamarck 
 
 printed at the expense of the Government and it 
 at once placed its author in a prominent position 
 among the naturalists of the day. Buffon's friend- 
 ship proved a valuable aid to him in various ways, 
 and doubtless helped to secure his speedy election 
 into the Academy of Sciences. But he still remained 
 exceedingly poor, and had a hard struggle to support 
 himself and the family that was now growing up 
 around him. 
 
 From the time of the appearance of the F/ore 
 Franc, aise Lamarck continued for fifteen years to work 
 mainly at botanical subjects, contributing papers to the 
 Memoirs of the Academy of Sciences, and producing 
 the successive botanical volumes in the great Encyclopedic 
 Methodique. These labours had raised him into the 
 front rank of botanists, but they did not make the 
 tenure of his appointment so secure that he had not 
 to defend his position. He was compelled to publish 
 a statement of the nature and importance of the duties 
 he had to perform, and at the same time he urged that 
 more ample provision should be made for the scientific 
 work of the Museum and Garden. The National 
 Convention took up the matter, and in the summer 
 of 1793 reorganised and enlarged the establishment. 
 Of the twelve new chairs then founded, the botanical 
 appointments were naturally bestowed on the two senior 
 distinguished botanists of the staff, Jussieu and Des- 
 fontaines, while Lamarck was offered one of the chairs 
 of zoology. When it is remembered that he was now 
 verging on 50 years of age, and that he had never 
 paid much attention to zoological matters, but had 
 given up his time and energies to botany, one may 
 
Professor of Invertebrate Zoology 349 
 
 well feel astonishment at the courage of the man in 
 accepting the appointment and resolving to make him- 
 self master of another science. The title of his chair 
 was " Professor of Zoology ; of insects, of worms and 
 of microscopic animals," and the annual stipend 2868 
 livres or about 115 sterling. Having made up his 
 mind to undertake the new duties, he threw himself 
 with such courage and zeal into them, that before many 
 years he was acclaimed as an even more accomplished 
 and original zoologist than he had been a botanist. 
 Yet he continued to find time for excursions into 
 physical science. He went on for a succession of years 
 publishing meteorological reports, which may be re- 
 garded as in some respects forerunners of the weather- 
 charts of recent times. He also entered the lists 
 against the prevalent chemical and physical opinions 
 of the day, propounding some extraordinary views 
 which had no experimental basis and were generally 
 regarded as too eccentric to require refutation. 
 
 In the course of his zoological studies Lamarck was 
 led directly and indirectly to make important contribu- 
 tions towards the advance of geology. In dealing with 
 the invertebrata, especially with the mollusca, he studied 
 and described the varied assemblage of fossil shells so 
 abundantly and perfectly preserved among the Tertiary 
 deposits of the Paris basin. Correlating the living with 
 the extinct forms, he was enabled to present a far 
 broader and more accurate picture of the invertebrate 
 division of the animal kingdom than had ever before 
 been attempted. Cuvier has been claimed as the great 
 founder of vertebrate Palaeontology; Lamarck may 
 with at least equal justice be regarded as the founder 
 
35 Lamarck 
 
 of the invertebrate half of the science. His researches 
 among the shells of the Paris basin furnished, as we 
 shall see, an accurately determined basis on which 
 Cuvier and Brongniart could work out the stratigraphy 
 of that region. 
 
 But Lamarck's original and philosophical genius 
 could not be confined within the limits of the mere 
 determination of new genera and species. From the 
 contemplation of these details, he advanced into broad 
 generalisations among the higher problems of biology. 
 He propounded views in organic evolution which, 
 though received at the time with ridicule and subse- 
 quently with neglect, have in later years been revived, 
 and meet now with a constantly increasing degree of 
 acceptance. His Philosophic Zoologique has become a 
 classic in biological literature, while his great work the 
 Animaux Sans Vertebres, which appeared in seven vol- 
 umes between 1815 and 1822, marks a memorable 
 epoch in the march of natural history, and will ever 
 remain one of the glories of French science. 
 
 Though Lamarck wrote little on geology, the extent 
 to which he had pondered over the problems of the 
 science, which in his time had hardly taken definite 
 shape, is well illustrated by the little volume which he 
 published in 1802 under the title of Hydrogeologiel 
 
 x The full title of this little known but extremely interesting 
 treatise is as follows : " Hydrogologie, ou Recherches sur 1'influence 
 qu'ont les eaux sur la surface du globe terrestre ; sur les causes de 
 1'existence du bassin des mers, de son deplacement et de son transport 
 successif sur les diffe~rentes points de la surface de ce globe ; enfin 
 sur les changemens que les corps vivans exercent sur la nature et 
 Tetat de cette surface. Par J. B. Lamarck, Membre de 1'Institut 
 National de France, Professeur-Administrateur au Museum d'Histoire 
 
On origin of Hills and Valleys 351 
 
 The object of this work was to propose and attempt 
 to solve four problems, the solution of which must 
 constitute the foundation of any true theory of the 
 earth, ist. What are the natural effects of the move- 
 ments of the terrestrial waters on the surface of the 
 globe ? 2nd. Why is the sea confined to a basin and 
 within limits that always separate it from the projecting 
 dry land ? 3rd. Has the basin of the sea always 
 existed as we now see it, and if not, what is the cause 
 that led to its being elsewhere, and why is it not there 
 still ? 4th. What is the influence of living organisms 
 on the mineral substances of the earth's surface and 
 crust, and what are the general results of this influence ? 
 i. Lamarck realised more clearly than most of his 
 contemporaries, the part played by terrestrial waters 
 on the surface of the land. He recognised that 
 nothing can ultimately resist the alternating influence 
 of wetness and drought, combined with that of heat 
 and cold, and that the disintegration of mineral sub- 
 stances by these atmospheric conditions prepares the 
 way for the erosive action of running water in all its 
 various forms. As the result of this action, plains 
 are hollowed out into ravines, and these are widened 
 into valleys. The spaces between rivers are worn into 
 ridges, which in course of time become high crests. 
 
 Naturelle &c." Paris, An X (1802). It is interesting to note that 
 this volume and Playfair's Illustrations of the Huttonian Theory were 
 published in the same year, and to contrast the opinions of the two 
 writers. In all that relates to the organic world, the French naturalist 
 had a far wider outlook than the Scottish philosopher, while on the 
 other hand, the latter showed a truer insight into most of the physical 
 problems of geology with which he dealt. 
 
35 2 Lamarck 
 
 If the surface of the land had been at first a vast 
 plain, yet at the end of a certain time, through the 
 operation of its water-courses, it would have lost that 
 aspect, and would ultimately come to be traversed with 
 mountains like those with which we are familiar. 
 
 In these deductions, the French philosopher re-echoed 
 the principles established by De Saussure, Desmarest 
 and Hutton. But he carried them to an extreme 
 which may possibly have raised a prejudice against 
 them. He declared that every mountain which has 
 not been erupted by volcanic action or some other 
 local catastrophe, has been cut out of a plain, so that 
 the mountain-summits represent the relics of that 
 plain, save in so far as its level has been lowered in 
 the general degradation. Geologists have accepted this 
 explanation for the systems of mountains which, having 
 no internal or tectonic structure peculiar to themselves, 
 appear to have been carved out of ancient tablelands. 
 Lamarck, however, though he speaks of local catas- 
 trophes, seems to have had no conception of any wide- 
 spread cause whereby the terrestrial crust has from 
 time to time been folded and driven upwards into 
 vast chains of mountains. He admits that in many 
 mountains the component strata are often vertical or 
 highly inclined. But he will not on that account believe 
 in any universal catastrophe, such as had been demanded 
 by many previous writers, and was still loudly advocated 
 in his own time by his fellow-countryman Cuvier. He 
 considers that the inclination of the strata may be due 
 partly to the natural slope of the surface on which 
 the sediments were originally deposited, like the talus- 
 slopes of mountains, partly and frequently to many 
 
On origin of Ocean-basin 353 
 
 kinds of accidents, such as arise from local subsidence. 
 But he enters into no further detail, and shows no 
 personal knowledge of the real structure of a true 
 mountain-chain. 
 
 The task of the fresh waters, according to this 
 thinker, is thus two-fold ; to erode the dry land, 
 thereby producing valleys and mountains, and to 
 spread the detritus over plains, before finally sweeping 
 it out to sea, where it tends towards the filling up of 
 the sea-basins. 
 
 2. In attempting to solve his second problem 
 Lamarck ventured far beyond his depth in regard to 
 the physics of the earth, and broached some crude 
 ideas, based on no reliable evidence, but directly con- 
 trary to such facts regarding the ocean as were known 
 in his time. He conceived the ocean-basin to owe 
 its existence and preservation to the perpetual oscilla- 
 tion of the tides, and partly also to a general westerly 
 movement of the water. He supposed the tidal 
 oscillation to be a gigantic force which has actually 
 eroded the basin and now prevents it from being 
 shallowed, through the deposit of land-derived sedi- 
 ment, by continually scouring this sediment out and 
 casting it up along the more sheltered shores of the 
 land. Since the sea does not cover the whole globe, but 
 is gathered into its vast basin, the centre of gravity of 
 the earth does not strictly coincide with what Lamarck 
 called its "centre of form." Owing to the shifting 
 of the ocean-bed westward, he thought that the centre 
 of gravity is simultaneously displaced and slowly makes 
 a revolution round the centre of form. In these 
 speculations the great naturalist displayed a singular 
 
354 Lamarck 
 
 misapprehension of the effects of the tides, and made 
 no allowance for any movement of the terrestrial crust. 
 3. The same limited acquaintance with the facts 
 which were needed for the solution of his difficulties 
 is not less conspicuous in the way in which he dealt 
 with his third problem. He thinks that in spite of 
 the tidal oscillations which seem to retard the deposit 
 of sediment over the sea-floor, the basin of the ocean 
 might eventually be filled up, or that at least the sea 
 would rise above its present mean level, if some 
 unceasingly active cause did not counteract this ten- 
 dency. Looking around at the margin of the land 
 in different quarters of the globe, he sees what seems 
 to him evidence that the waters of the ocean are 
 subject to a continual impulse which drives them 
 from east to west, due, he believed, to the influence 
 chiefly of the moon, but partly also of the sun. He 
 does not show, however, in what form this impulse is 
 imparted otherwise than in the tidal wave. The 
 eastern coasts of the continents appear in his eyes to 
 be wasted by the attacks of the sea, while the western 
 shores, being sheltered from these attacks, receive 
 deposits of sediment. He looks on the Gulf of 
 Mexico as a vast hollow, dug out of the land by the 
 westerly advance of the Atlantic. The eastern side 
 of Asia, with its chains of islands and the passage 
 opened for the marine currents between these islands 
 and Australia, appeals to his mind as a striking 
 example of the truth of his generalisation, while the 
 eastern side of America is hardly less confirmatory, 
 although the sea has not yet cut through the Isthmus 
 of Panama. 
 
On the study of Fossils 355 
 
 Much more interesting and satisfactory is Lamarck's 
 fresh demonstration, from authentic and irrefragable 
 evidence, of the long accepted truth that the sea has 
 once covered many parts of the surface of the globe 
 from which it has long disappeared. This evidence 
 rests on the occurrence of organic remains, and in 
 dealing with it he evidently feels himself at home with 
 his subject, and launches warmly into its discussion. 
 The term "fossil," as we have seen (p. 215), had 
 been indiscriminately applied to any mineral substance 
 dug out of the earth, but Lamarck now for the first 
 time definitely restricts it to the u still recognisable 
 remains of organised bodies." x After citing a number 
 of examples of the occurrence of such remains in the 
 heart of mountains, at great heights above the sea 
 and in different widely separated parts of the globe, 
 he proceeds to dwell on the importance of fossils as 
 monuments that furnish one of the chief means of 
 ascertaining the revolutions which our globe has 
 undergone. He urges naturalists to study fossil 
 shells, to compare them with their analogues in our 
 present seas, to investigate carefully where each species 
 is found, the banks formed of them, the different layers 
 which these banks may display, and other associated 
 features. He points out, as Lavoisier had done before 
 him (p. 344), that among fossil shells some are pelagic 
 and some littoral, and that they even occasionally in- 
 clude terrestrial and fluviatile forms. These last would, 
 in his opinion, be much more numerous had not their 
 greater fragility led to their being generally broken and 
 destroyed before they could be washed into the sea. 
 1 Hydrogeologie, p. 55. 
 
356 Lamarck 
 
 Discussing the cause of the former long-continued 
 sojourn of the sea on so many parts of the surface 
 of the land, he inquires whether we are to invoke 
 the occurrence of the Deluge or some great catas- 
 trophes, as had so often been done in the past, and 
 as continued to be done for many years afterwards 
 by Cuvier. He will admit such an extraordinary 
 cause if it be granted to have endured for the vast 
 periods of time which the accumulation of thick and 
 regular deposits of marine remains must have required. 
 But he would rather seek for some explanation that 
 will be more in accordance with the observed order 
 of Nature. He was thus a follower of the Huttonian 
 theory. 
 
 And here the great naturalist breaks forth in a 
 tone that reminds one of the language of his Greek 
 prototype, Aristotle : " In this globe which we in- 
 habit, everything is subject to continual and inevitable 
 changes. These arise from the essential order of 
 things, and are effected with more or less rapidity or 
 slowness, according to the varying nature or position 
 of the objects implicated in them. Nevertheless they 
 are accomplished within a certain period of time. 
 For Nature, time is nothing, and is never a diffi- 
 culty ; she always has it at her disposal, and it is for 
 her a means without bounds, wherewith she accom- 
 plishes the greatest as well as the least of her tasks." 
 " Oh, how vast is the antiquity of our earth ! and 
 how small are the ideas of those who assign to the 
 existence of this globe a duration of six thousand 
 and some hundreds of years from its beginning to 
 our own days ! " " Losing trace of what has once 
 
On oceanic displacement 357 
 
 existed, we can hardly believe nor even conceive the 
 immensity of our planet's age. Yet how much vaster 
 still will this antiquity appear to man when he shall 
 have been able to form a just conception of the 
 origin of living creatures, as well as of the causes of 
 their gradual development and improvement, and 
 above all when he shall perceive that time and the 
 requisite conditions having been necessary to bring 
 into existence all the living species now actually to be 
 seen, he himself is the final result and actual climax 
 of this development of which the ultimate limit, if 
 such there be, can never be known." 1 
 
 With such a limitless vista of past time to 
 contemplate, Lamarck could indulge in unfettered 
 speculation on the secular displacement of the ocean 
 basin, and the concomitant submergence of the land. 
 Inappreciably slow though the mutation might be, he 
 believed it to be part of the regular order of nature, 
 proceeding without interruption until every part of 
 the dry land had in succession become the bed of 
 the sea. In this slow westerly movement, the ocean 
 seemed to him to have travelled round the globe, 
 not once but perhaps many times, every part of the 
 land becoming first the shore, and then passing under 
 the scour of the great oceanic waters until at last 
 reduced to form the bottom of the marine abysses. 
 He thought that this displacement of the basin of 
 the sea, by producing a constantly variable inequality 
 in the terrestrial radii, causes a shifting of the centre 
 of gravity of the globe as well as of the two poles, 
 and that as this variation, markedly irregular though 
 1 O/>. dt. pp. 67, 88, 89. 
 
358 Lamarck 
 
 it be, appears not to be confined within definite 
 limits, probably every point on the surface of our 
 planet may have successively passed through all the 
 different terrestrial climates. 1 
 
 Though his theory of the interchange of land and 
 sea cannot be accepted, it is impossible to read with- 
 out admiration Lamarck's marshalling of the facts on 
 which he relied, and his acute reflections on the deduc- 
 tions to be drawn from the characters and probable 
 habitats of organic remains. He points out the im- 
 portance of distinguishing pelagic from littoral shells, 
 each series being usually found in distinct beds, the 
 one marking deep water the other former shore-lines. 
 Every part of the earth's surface that has once been 
 overspread by the sea has had twice a zone of 
 littoral shells and once a deposit of pelagic shells, 
 making three distinct and successive formations, 
 representing the passage of a vast lapse of time. 
 No sudden catastrophe is admissible as an explanation 
 of the facts ; such an event would have jumbled the 
 organisms together and would have broken the more 
 delicate shells, which have nevertheless been admirably 
 preserved in great numbers among the other fossils. 
 Again, the bivalves, with which many of the lime- 
 stones are crowded, would not so commonly have 
 retained their valves in contact, unless they had lived 
 and died where their remains are found. In 
 Lamarck's opinion a large part of the calcareous 
 material, now to be found on the surface and within 
 the crust of the earth, has been derived from once 
 living organisms. He will not admit the propriety 
 1 Op. cit. p. 87. 
 
On origin of Limestone 359 
 
 of the term <c primitive," applied by mineralogists to 
 the more ancient limestones. Though all trace of 
 organic structure may have disappeared from these 
 strata, he nevertheless believes them to have had an 
 organic origin, and he can indicate the process by 
 which the organic structures might be destroyed. 
 He even goes so far as to affirm that such cal- 
 careous matter did not exist in the primitive earth, 
 but like other animal and vegetable substances, only 
 came into existence when it was secreted by living 
 organisms. 
 
 4. To the treatment of the fourth problem Lamarck 
 devotes nearly as much space as to the other three 
 Uken together, tempted doubtless to this greater 
 di;cursiveness by the opportunity to re-state and 
 develop his peculiar views in physics and chemistry, 
 anc to claim for the subject a far more important 
 plae in scientific investigation than his contem- 
 pora*ies seemed disposed to admit. Without entering 
 here into his controversy, it may be sufficient to note 
 the more important geological observations and 
 deducions wherein the author was either wholly 
 or patly in the right, and where he led the way 
 in a ine of inquiry wherein much still remains to 
 be acamplished. 
 
 The crust of the earth, conjectured by Lamarck to 
 be perhps 3 or 4 leagues thick (13 to 17 kilometres 
 or 8 to loj English miles), was pictured by him to 
 be, as rgards its outer part, in a continual state of 
 alteratior; ceaselessly worked over by the various 
 forms oi water, by the displacements and alternate 
 passages f the ocean-basin, by the continual deposits 
 
360 Lamarck 
 
 of all kinds formed by living organisms on its exposed 
 portions ; further by the changes, the upheavals, the 
 accumulations, the subsidences and excavations pro- 
 duced in its thickness by volcanoes and earthquakes. 
 Under these manifold influences it must certainly 
 have undergone, in its condition and in the nature 
 of its parts, variations which but for these different 
 causes could never have taken place. All composite 
 bodies tend to decay into their component constituents. 
 Yet the visible crust of the earth consists almost 
 entirely of compound materials. How is this fact 
 to be accounted for ? There must be, he thought 
 some other potent force in Nature which acts antag- 
 onistically to the tendency towards the resolution tf 
 combinations into their component constituents, aid 
 he believed this force to be supplied by living orgin- 
 isms, or by what he calls the Pouvoir de la 7 ie. 
 Having long watched the operations of living pants 
 and animals, he saw that the organic action of Iving 
 bodies unceasingly forms combinations of substmces, 
 which, without this action, would never have come 
 into existence. From this well-founded observation, 
 however, he leaped to the astounding generalsation 
 that " the compound mineral substances, whch are 
 to be found in almost every part of the outc crust 
 of the globe and form most of its compsition, 
 while at the same time they are continually modifying 
 it by the changes they undergo, are all, withoit excep- 
 tion, the result of the remains and debris <f living 
 bodies." He had broached this view m>re than 
 eighteen years earlier and he now complain that so 
 striking a truth, only discoverable by obervation, 
 
On consolidation of Rocks 361 
 
 should have been rejected and apparently scorned 
 by the very men who ought to have been the first 
 to welcome it. We can hardly wonder, however, 
 that his contemporaries should have refrained from 
 treating this speculation as a serious contribution to 
 science. 
 
 And yet though the conclusion was wholly unten- 
 able, it must in justice to Lamarck be admitted that 
 he perceived in this matter, far more vividly than 
 any other naturalist of his time, the importance of 
 the part played by plants and animals in effecting 
 geological changes by decomposing mineral matter, 
 and thus modifying the surface of the earth and pro- 
 viding fresh materials for its crust. No one before 
 his day had been able to follow so clearly the suc- 
 cessive stages through which organic remains pass until 
 they become crystalline stone, presenting no trace of 
 their original organic structure. He distinguished 
 between the consolidation of stratified rocks through 
 the deposit of fine sediment (Lapidescence par sedi- 
 mens\ and through permeation by some cementing 
 material (Lapidescence par infiltration)^ He showed 
 that agates and petrifactions are examples of the 
 results of such infiltration, but he came to the singular 
 conclusion that the " elementary earth," " vitreous 
 earth," or silica of the chemists, has been so potent 
 an agent in infiltration that it constitutes the base 
 
 1 In this department of his subject Lamarck held much more 
 accurate opinions than Hutton and Playfair, who were so carried 
 away by their view of the efficacy of underground heat, as to 
 believe that flints and agates had been injected in a molten state 
 into the rocks in which they are now found. 
 
362 Lamarck 
 
 of all the earths and stones of every sort, in short, 
 of solid matter everywhere. 
 
 When he thus threw aside as error all that had 
 then been ascertained as to the chemistry of minerals, 
 he found no difficulty in accounting for all rocks as 
 the results of the decay of organic bodies. He looked 
 on granite, for example, not as the " primitive " rock 
 which mineralogists had called it, nor as directly con- 
 nected with the material that forms the interior of 
 the globe, but as due to the transport of the decaying 
 debris of organisms by rivers, and to the accumulation 
 of this detritus on the floor of the sea. He believed 
 that all argillaceous materials come from the decay of 
 plants and all calcareous materials from the remains 
 of animals, and that from these two chief sources 
 the most important and abundant earthy and stony 
 bodies are derived, all the other mineral substances 
 being only mixtures or modifications of these. Even 
 metals appeared to him divisible into two series, 
 according as their earthy base has been supplied by 
 animals or by plants. Here again he generalised from 
 the undoubted precipitation of some metallic salts by 
 organic matter to the production of all metallic sub- 
 stances from the same cause. His discussion ends 
 with a pungent attack on the chemists of his day and 
 their methods, and he declares that though all the 
 world may believe them, he is content to be alone in 
 his disbelief. 
 
 There can be little doubt that this spirit of opposi- 
 tion to many of the prevalent opinions of the time, 
 together with the apparent extravagance of some of 
 his doctrines, conspired to detract from the position 
 
His services to Geology 363 
 
 and influence to which Lamarck's splendid abilities 
 and achievements justly entitled him among his con- 
 temporaries. During the last ten years of his long 
 life he suffered from total blindness, and had to rely 
 on the affectionate devotion of his eldest daughter for 
 the completion of such works as he had in progress 
 before his eyesight failed. The world is becoming 
 more conscious now of what it owes to the genius 
 of this illustrious naturalist. Among those students 
 of science who have most reason to cherish his 
 memory, geologists should look back gratefully to his 
 services in starting the science of Palaeontology, in 
 propounding the doctrine of evolution and in affirm- 
 ing with great insight some of the fundamental 
 principles of modern geology. 
 
 Returning now to the Paris basin, we may take note 
 that not until the year 1808 was the Tertiary strati- 
 graphy of this district worked out in some detail, so as 
 to furnish a foundation for the establishment of a general 
 system of stratigraphical geology in France. This task 
 was accomplished by two men who have left their mark 
 upon the history of the science, Cuvier and Brongniart. 
 
 Georges Chretien Leopold Dagobert Cuvier (1769- 
 1832) came of an old Protestant family in the Jura, 
 which in the sixteenth century had fled from persecu- 
 tion and had settled at Montbeliard, then the chief 
 town of a little principality belonging to the Duke of 
 Wilrtemberg. He was born at that place on 23rd 
 August 1769, and after a singularly brilliant career 
 at school and at the Caroline Academy of Stuttgart, 
 became tutor in a Normandy family living near Fecamp. 
 He had been drawn into the study of natural history, 
 
364 Cumer 
 
 when a mere child, by looking over the pages of 
 Buffon, and had with much ardour taken to the 
 observation of insects and plants. In Normandy, 
 the treasures of the sea were opened to him. 
 Gradually his dissections and descriptions, though 
 not published, came to the notice of some of the 
 leading naturalists of France, and he was eventually 
 induced to come to Paris, where, after rilling various 
 appointments, he was elected to the chair of Compara- 
 tive Anatomy in 1795. 
 
 Cuvier's splendid career belongs mainly to the 
 history of biology. We are only concerned here in 
 noting how he came to be interested in geological 
 questions. He tells himself that some TerebratuLe 
 from the rocks at Fecamp suggested to him the idea 
 of comparing the fossil forms with living organisms. 
 When he settled in Paris, he pursued this idea, 
 never losing an opportunity of studying the fossils 
 to be found in the different collections. He began 
 by gathering together as large a series as he could 
 obtain of skeletons of living species of vertebrate 
 animals, as a basis for the comparison and determina- 
 tion of extinct forms. As a first essay in the new 
 domain which he was to open up to science, he read 
 to the Institute, at the beginning of 1796, a memoir 
 in which he demonstrated that the fossil elephant 
 belonged to a different species from either of the 
 living forms. Two years later, having had a few 
 bones brought to him from the gypsum quarries of 
 Montmartre, he saw that they indicated some quite 
 unknown animals. Further research qualified him 
 to reconstruct the skeletons, and to demonstrate their 
 
Brongniart 365 
 
 entire difference, both specifically and generically, from 
 any known creatures of the modern world. He was 
 thus enabled to announce the important conclusion 
 that the globe was once peopled by vertebrate animals 
 which, in the course of the revolutions of its surface, 
 have entirely disappeared. 
 
 These discoveries, so remarkable in themselves, could 
 not but suggest many further inquiries to a mind 
 so penetrating and philosophical as that of Cuvier. 
 He narrates how he was pursued and haunted by 
 the desire to know why these extinct forms dis- 
 appeared, and how they had come to be succeeded 
 by others. It was at this point that he entered 
 upon the special domain of geology. He found that 
 besides studying the fossil bones in the cabinet, it 
 was needful to understand, in the field, the con- 
 ditions under which they have been entombed and 
 preserved. He had himself no practical acquaint- 
 ance with the structure and relations of rocks, but 
 he was fortunate in securing the co-operation of a 
 man singularly able to supply the qualifications in 
 which he was himself deficient. 
 
 Alexandre Brongniart (1770-1847) Cuvier's associate, 
 was a year younger than the great anatomist. Born 
 in Paris, he began his career early in life by endeav- 
 ouring to improve the art of enamelling in France. 
 Thereafter he served in the medical department of 
 the army until he was attached to the Corps of Mines, 
 and was made director of the famous porcelain factory 
 of Sevres. He had long given his attention to 
 minerals and rocks, and was eventually appointed 
 professor of mineralogy at the Museum of Natural 
 
366 Cuvier and Brongniart 
 
 History. But his tastes led him also to study zoology. 
 Thus, among his labours in this field, he worked out 
 the zoological and geological relations of Trilobites. 
 There was consequently in their common pursuits, a 
 bond of union between him and Cuvier. They had 
 both entered upon a domain that was as yet almost 
 untrodden ; and each brought with him knowledge 
 and experience that were needful to the other. 
 
 Accordingly they engaged in a series of researches 
 in the basin of the Seine, which continued for some 
 years. Cuvier relates that during four years he made 
 almost every week an excursion into the country 
 around Paris, for the sake of studying its geological 
 structure. Particular attention was given to two 
 features, the evidence of a definite succession among 
 the strata, and the distinction of the organic remains 
 contained in them. At last the results of these in- 
 vestigations were embodied in a joint memoir by 
 Cuvier and Brongniart, which first appeared in the 
 year iSoS. 1 
 
 The two naturalists continued their researches with 
 great industry during the following years. An account 
 of these additional observations was read by them 
 before the Institute in April 1810, and was published 
 as a separate work with a map, sections, and plate of 
 fossils in i8n. 2 Referring afterwards to this conjoint 
 essay and its subsequent enlargement, Cuvier generously 
 wrote that though it bore his name, it had become 
 
 1 Journal des Mines, tome xxiii. (1808), p. 4.21. 
 
 2 Essai sur la Geographic Mineralogique des Environs de Paris, avec une 
 Carte geognostique et des Coupes de terrain, 410, 1 8 1 1 . An enlarged 
 edition of this separate work appeared in 1822. 
 
Their work in the Paris Basin 367 
 
 almost entirely the production of his friend, from the 
 infinite pains which, ever after the first conception of 
 their plan, and during their various excursions, he 
 had bestowed upon the thorough investigation of all 
 the objects of the inquiry, and in the preparation of 
 the essay itself. 1 Brongniart's experience as a mining 
 engineer would naturally make him fitter than Cuvier 
 for the requirements of stratigraphical research. 
 
 It is not necessary for our present purpose to trace 
 the development of view shown by these observers 
 during the three years that elapsed between the appear- 
 ance of their first sketch and that of their illustrated 
 quarto memoir. It will be enough to note the general 
 characters of their first essay, and to see how far in 
 advance it was of anything that had preceded it. 
 
 After briefly describing the limits and general feat- 
 ures of the Seine basin, the authors proceed to show 
 that the formations which they have to consider were 
 deposited in a vast bay or lake, of which the shores 
 consisted of Chalk. They point out that the deposits 
 took place in a certain definite order, and can be easily 
 recognised by their lithological and palaeontological 
 characters throughout the district. They classify 
 them first broadly into two great groups, which they 
 afterwards proceed to subdivide into minor sections. 
 The first of these groups, covering the Chalk of the 
 lower grounds, consists partly of the plateau of lime- 
 stone without shells, and partly of the abundantly 
 shell-bearing Calcaire Grossier. The second group 
 comprises the gypseo-marly series, not found uniformly 
 distributed, but disposed in patches. 
 
 1 Difcours sur les Revolutions de la Surface du Globe, 6th edit. p. 294. 
 
368 Cuvier and Brongniart 
 
 Starting from the Chalk of the north of France, 
 the two observers succinctly indicate the leading char- 
 acters of that deposit, its feeble stratification, chiefly 
 marked by parallel layers of dark flints, the varying 
 distances of these layers from each other, and the dis- 
 tinctive fossils. Putting together the organisms they 
 had themselves collected, and those previously ob- 
 tained by Defrance, they could speak of fifty species 
 of organic remains known to occur in the Chalk a 
 small number compared with what has since been 
 found. The species had not all been determined, but 
 some of them, such as the belemnites, had been noted 
 as different from those found in the " compact lime- 
 stone," or Jurassic series. 
 
 From the platform of Chalk, Cuvier and Brongniart 
 worked their way upward through the succession of 
 Tertiary formations. At the base of these, and resting 
 immediately on the Chalk, came the Plastic Clay a 
 deposit that in many respects presented strong con- 
 trasts to the white calcareous formation underneath it. 
 It showed no passage into that formation, from which, 
 on the contrary, it was always abruptly marked off, 
 and it yielded no organic remains. The two geologists 
 accordingly drew the sound inference that the clay and 
 the chalk must have been laid down under very 
 different conditions of water, and they believed that 
 the animals which lived in the first period did not 
 exist in the second. They likewise concluded that 
 the abrupt line of junction between the two forma- 
 tions might indicate a long interval of time, and 
 they inferred, from the occurrence of an occasional 
 breccia of chalk fragments at the base of the clay, 
 
Their work in the Paris Basin 369 
 
 that the chalk was already solid when the clay was 
 deposited. 
 
 The next formation in ascending order was one of 
 sand and the Calcaire Grossier. It was shown to 
 consist of a number of bands or alternations of lime- 
 stone and marl ; following each other always in the 
 same order, and traceable as far as the two observers 
 had followed them. Some of the strata might diminish 
 or disappear, but what were below in one district were 
 never found above in another. "This constancy in 
 the order of superposition of the thinnest strata," the 
 writers remark, "for a distance of at least 12 myria- 
 metres (75 English miles), is in our opinion one of 
 the most remarkable facts which we have met with in 
 the course of our researches. It should lead to results 
 for the arts and for geology all the more interesting 
 that they are sure." 
 
 One of the most significant parts of the essay is the 
 account it gives of the method adopted by the explorers 
 to identify the various strata from district to district. 
 They had grasped the true principle of stratigraphy, 
 and had applied it with signal success. The passage 
 deserves to be quoted from its historical importance 
 in the annals of science : u The means which we have 
 employed, among so many limestones, for the recog- 
 nition of a bed already observed in a distant quarter, 
 has been taken from the nature of the fossils contained 
 in each bed. These fossils are generally the same in 
 corresponding beds, and present tolerably marked differ- 
 ences of species from one group of beds to another. 
 It is a method of recognition which up to the present 
 has never deceived us. 
 
 2 A 
 
37 Cuvier and Brongniart 
 
 " It must not be supposed, however, that the differ- 
 ence in this respect between one bed and another is 
 as sharply marked off as that between the chalk and 
 the limestone. The characteristic fossils of one bed 
 become less abundant in the bed above and disappear 
 altogether in the others, or are gradually replaced 
 by new fossils, which had not previously appeared." 1 
 
 The authors then proceed to enumerate the chief 
 groups of strata composing the Calcaire Grossier, 
 beginning at the bottom and tracing the succession 
 upward. It is not necessary to follow them into 
 these details. We may note that, even at that time, 
 the prodigious richness of the lower parts of this 
 formation in fossil shells had been shown by the 
 labours of Defrance, who had gathered from them no 
 fewer than 600 species, which had been described 
 by Lamarck. It was remarked by Cuvier and Brong- 
 niart that most of these shells are much more unlike 
 living forms than those found in the higher strata. 
 These observers also drew, from the unfossiliferous 
 nature of the highest parts of the formation, the in- 
 ference that during the time when the Calcaire Grossier 
 was deposited slowly, layer after layer, the number of 
 shells gradually diminished until they disappeared, the 
 waters either no longer containing them or being un- 
 able to preserve them. 
 
 The gypseous series which succeeds offered to 
 Cuvier and Brongniart an excellent example of what 
 Werner termed a " formation," inasmuch as it pre- 
 sents a succession of strata markedly different from 
 each other, yet evidently deposited in one continuous 
 ^-Journal des Mines, xxiii. p. 436. 
 
Their work in the Paris Basin 371 
 
 sedimentation. Cuvier had already startled the world 
 by his descriptions of some of the extinct quadrupeds 
 entombed in these deposits. In calling attention to 
 the occurrence of these animals, the authors refer to 
 the occasional discovery of fresh-water shells in the 
 same strata, and to the confirmation thereby afforded 
 to the opinion of Lamanon and others, that the gypsum 
 of Montmartre and other places around Paris had been 
 deposited in fresh-water lakes. 
 
 They saw the importance of a thin band of marl 
 at the top of the gypseous series which, in spite of 
 its apparent insignificance, they had found to be trace- 
 able for a great distance. Its value arose partly from 
 its marking what would now be called a lithological 
 horizon, but even more from its stratigraphical in- 
 terest, inasmuch as it served to separate a lacustrine 
 from a marine series. All the shells below this seam 
 were found to be fresh-water forms. Those in the 
 seam itself were species of Tellina, and all those in 
 the strata above were, like that shell, marine. The 
 two geologists, struck by the marked difference of 
 physical conditions represented by the two sections 
 of the gypseous series, had tried to separate it 
 into two formations, but had not carried out the 
 design. 
 
 Higher up in the series, above a group of sands 
 and marine sandstones, an unfossiliferous siliceous 
 limestone, and a sandstone formation without shells, 
 Cuvier and Brongniart found a widespread fresh-water 
 siliceous limestone or millstone, specially characterised 
 by containing Limnea, Planorbis, and other lacustrine 
 shells. 
 
37 2 Cumer and Brongniart 
 
 The youngest formation which they described was 
 the alluvium of the valleys, with bones of elephants 
 and trunks of trees. 
 
 Subsequent research has slightly altered and greatly 
 elaborated the arrangement made by Cuvier and 
 Brongniart of the successive Tertiary formations of 
 the Paris basin. But although the subdivision of the 
 strata into definite stratigraphical and palaeontological 
 platforms has been carried into far greater detail, 
 the broad outlines traced by them remain as true 
 now as they were when first sketched a century 
 ago. These two great men not merely marked out 
 the grouping of the formations in a limited tract of 
 country. They established on a basis of accurate 
 observation the principles of palaeontological strati- 
 graphy. They demonstrated the use of fossils for 
 the determination of geological chronology, and they 
 paved the way for the enormous advances which 
 have since been made in this department of science. 
 For these distinguished labours they deserve an 
 honoured place among the Founders of Geology. 
 Cuvier's contributions to zoology, palaeontology, and 
 comparative anatomy were so numerous and import- 
 ant that his share in the establishment of correct 
 stratigraphy is apt to be forgotten. But his name 
 must ever be bracketed with that of Brongniart for 
 the service rendered to geology by their conjoint 
 work among the Tertiary deposits of the Paris 
 basin. 
 
 Although Cuvier's researches among fossil animals, 
 and the principles of comparative anatomy which 
 he promulgated, contributed powerfully towards the 
 
Cumer's Contributions to Geology 373 
 
 foundation and development of vertebrate palaeon- 
 tology as a distinct department of biology, his services 
 to geology proper may be looked upon as almost 
 wholly comprised in the joint essay with Brongniart. 
 Geology indeed had much fascination for him, and 
 he wrote a special treatise on it entitled A Discourse 
 on the Revolutions of the Surface of the Globed In 
 this work he maintains the opinion that the past 
 history of the earth has been marked by the occur- 
 rence of many sudden and widespread catastrophes, 
 exceeding in violence anything we can imagine at the 
 present day, whereby the surface of the land has been 
 overwhelmed by the sea, and its inhabitants have been 
 destroyed. Briefly reviewing the usual action of rain 
 and frost, brooks and rivers, the sea and volcanoes, 
 he comes to the conclusion that the former revolu- 
 tions were so stupendous that " the thread of Nature's 
 operations was broken by them, that her progress was 
 altered, and that none of the agents which she employs 
 
 1 In its first form it was prefixed to the Recherches sur les Ossemens 
 Fossiles as a Preliminary Discourse on the Theory of the Earth (1821). 
 It was afterwards published separately as the Discours sur les Revolutions 
 de la surface du Globe (1826). The work showed no marked ad- 
 vance in geological progress. Yet it went through six editions in the 
 author's lifetime, the latest (6th) corrected and augmented by him 
 appearing in 1830. The versions published in England were edited 
 and copiously annotated by Prof. Jameson of Edinburgh, whose notes 
 to the early editions supply some curious samples of his adherence to 
 Wernerianism. Cuvier was also the author of a Report on the Pro- 
 gress of the Natural Sciences, presented to the Emperor Napoleon in 
 1808, in which he expressed various vague and indefinite opinions on 
 geological questions. In his earlier years his geological bias was 
 decidedly towards Wernerianism (see the references in his Eloge on 
 De Saussure already cited, p. 308). 
 
374 Cuvier and Lamarck 
 
 to-day could have sufficed for the accomplishment of 
 her ancient works." 1 
 
 The contrast between these opinions and those of 
 Lamarck on the same subject could not fail to im- 
 press the minds of their contemporaries. Cuvier was 
 a Cataclysmist, Lamarck an Evolutionist. The former 
 by his brilliant style, his social charm, and his in- 
 fluential position commanded the attention of the 
 world, so that his geological volume, though views 
 which it specially advocated have long since been aban- 
 doned, went through a number of successive editions, 
 besides being translated into English and German. It 
 became, indeed, one of the chief portals through which 
 the ordinary reader of the day made his acquaintance 
 with the science of geology. Lamarck's little Hydro- 
 geologie, on the other hand, met with no such success. 
 Though in many respects, in spite of its occasional 
 extravagance, a more philosophical treatise than 
 Cuvier's, it never reached a second edition, has never 
 been reprinted, and has almost sunk out of sight. 
 
 Notwithstanding the prominence assigned by Cuvier 
 to great cataclysms in the past history of our planet, 
 he recognised that there has been, on the whole, an 
 upward progress among the races of animals that have 
 successively flourished upon the earth. The oviparous 
 quadrupeds, for instance, preceded the viviparous. 
 But, unlike Lamarck, he set his face against evolution, 
 and refused to admit that the existing races can be 
 modifications of ancient forms, brought about by 
 local circumstances, change of climate or other causes ; 
 for if any such evolution had taken place, he claimed 
 1 Discours Prelimlnaire, p. xiii. 
 
Cumer on the Deluge 375 
 
 that some evidence of it should have been found in 
 the shape of intermediate forms in the rocks. He 
 regarded species as permanent, though varieties might 
 arise. He offered a detailed argument to prove, from 
 physical facts and from the history of nations, that the 
 present continents are of modern date, and he entered 
 into an elaborate refutation of the alleged antiquity 
 of some peoples. He believed, with De Luc and 
 Dolomieu, in opposition to the opinions so well 
 expressed by Lamarck, that if any conclusion has 
 been well-established in geology, it is that a great 
 and sudden catastrophe befell the surface of the earth 
 some five or six thousand years ago, whereby the 
 countries inhabited by man were devastated and their 
 inhabitants were destroyed. At that time portions of 
 the sea-floor were upraised to form the present dry 
 land. But the rocks show that this land had previously 
 been inhabited, if not by man, at least by land-animals, 
 and thus that one preceding revolution, if not more, 
 had submerged these tracts and swept away their 
 population. 
 
 But it was the relation of such terrestrial revolu- 
 tions to the organic world which chiefly attracted the 
 great French naturalist. He could foresee the deeply 
 interesting problems that awaited solution in regard 
 to the alternation of sedimentary materials and the 
 succession of organic remains in the great series of 
 stratified formations, and he concludes his discourse 
 with these eloquent words : " What a noble task it 
 would be were we able to arrange the objects of the 
 organic world in their chronological order, as we have 
 arranged those of the mineral world. Biology would 
 
376 Cumer's Eloges 
 
 thereby gain much. The development of life, the 
 succession of its forms, the precise determination of 
 those organic types that first appeared, the simultaneous 
 birth of certain species and their gradual extinction 
 the solution of these questions would perhaps en- 
 lighten us regarding the essence of the organism as 
 much as all the experiments that we can try with 
 living species. And man, to whom has been granted 
 but a moment's sojourn on the earth, would gain the 
 glory of tracing the history of the thousands of ages 
 which preceded his existence and of the thousands of 
 beings that have never been his contemporaries." x 
 
 Cuvier's brilliant career is well known, but I am 
 only concerned at present with those parts of it 
 which touch on geological progress. In 1802, the 
 year in which Lamarck's Hydrogeologie appeared, he 
 became perpetual Secretary of the Institute of France, 
 and it was in this capacity that he composed that 
 remarkable series of Eloges in which so much of 
 the personal history of the more distinguished men 
 of science of his time is enshrined. Eloquent and 
 picturesque, full of knowledge and sympathy, these 
 biographical notices form a series of the most 
 instructive and delightful essays in the whole range 
 of scientific literature. They include sketches of 
 the life and work of De Saussure, Pallas, Werner, 
 Desmarest, Sir Joseph Banks, Hatly, and Lamarck. 
 
 Five years after the appearance of the earliest con- 
 joint memoir by Cuvier and Brongniart, the structure 
 of the country which they described was still further 
 explored and elucidated by a man who afterwards 
 1 From the first edition of the Discours Preliminaire, 1821. 
 
nOmalius cfHalloy 377 
 
 rose to fill an important place among the geologists 
 of Europe J. J. d'Omalius d'Halloy (1783-1875). 
 In 1813 this able observer read to the Institute a 
 memoir on the geology of the Paris basin and the 
 surrounding regions. 1 It corrected and extended the 
 work of his predecessors among the Tertiary forma- 
 tions, but its interest for our present purpose centres 
 mainly in its important contribution to the stratigraphy 
 of the Secondary rocks. He recognised the leading 
 subdivisions of the Cretaceous series, and actually 
 showed the extent of the system upon a map. He 
 likewise ascertained the stratigraphical relations and 
 range of the Jurassic system, which he called the 
 " old horizontal limestone," and which he correctly 
 depicted in its course outside the Chalk. His little 
 map, with its clear outlines and colours, is of historical 
 importance as being the first attempt to construct a 
 true geological map of a large tract of France. It 
 was not a mere chart of the surface rocks, like 
 Guettard's, but had a horizontal section, which showed 
 the Jurassic series lying unconformably upon the edges 
 of the Palaeozoic slates, and covered in turn by the 
 Gault and the Chalk. 
 
 1 Ann. des Mines, i. (1817), p. 251. He was the author of 
 numerous subsequent memoirs on the geology of Belgium and the 
 north of France, as well as of several excellent text books of the 
 science. 
 
CHAPTER XII 
 
 THE Rise of Stratigraphical Geology in England. Michell, White- 
 hurst, William Smith, Thomas Webster, the Geological 
 Society of London, W. H. Fitton. Early teachers and text- 
 books. Influence of Lyell. 
 
 WHILE in France it was the prominence and richly 
 fossiliferous character of the Tertiary strata which 
 first led to the recognition of the value of fossils in 
 stratigraphy, and to the definite establishment of the 
 principles of Stratigraphical geology, in England a 
 similar result was reached by a study of the Secondary 
 formations, which are not only more extensively 
 developed there than the younger series, but display 
 more clearly their succession and persistence. But 
 in both countries the lithological sequence, being the 
 more obvious, was first established before it was con- 
 firmed and extended by a recognition of the value 
 of the evidence of organic remains. 
 
 Early in the eighteenth century Strachey published 
 the succession of formations from the Coal to the 
 Chalk (p. 194). Michell in 1760 gave a clear ac- 
 count of the stratified arrangement of the sedimentary 
 formations, describing their general characters and the 
 persistence of these characters for great distances, and 
 
Michell on Geological Succession 379 
 
 showing that while on the flat ground the strata re- 
 main nearly level, they gradually become inclined as 
 they approach the mountains. 1 He pointed out that 
 the mountains are formed generally of the lower or 
 older rocks, while the more level ground lies usually 
 on the upper and nearly horizontal strata. He re- 
 marked further that the same sets of strata, in the 
 same order, are generally met with in crossing Britain 
 towards the sea, the direction of the ridge being 
 towards the north-north-east and south-south-west. 
 That he was familiar with the broad features of the 
 succession of the geological formations in England, 
 from the Coal-measures of Yorkshire up to the Chalk, 
 is shown by an interesting table which seems to have 
 been drawn up by him about 1788 or 1789, and 
 which was published after his death. 2 
 
 Michell enables us to form a clear conception of his 
 views by the following illustration. " Let a number 
 of leaves of paper," he remarks, " of several different 
 sorts or colours, be pasted upon one another ; then 
 bending them up into a ridge in the middle, conceive 
 them to be reduced again to a level surface, by a plane 
 so passing through them as to cut off all the part that 
 has been raised. Let the middle now be again raised a 
 little, and this will be a good general representation of 
 most, if not all, large tracts of mountainous countries, 
 together with the parts adjacent, throughout the whole 
 world. From this formation of the earth it will follow 
 that we ought to meet with the same kinds of earths, 
 stones, and minerals, appearing at the surface in long 
 
 1 Phil. Trans, vol. li. (1760), part ii. p. 582, et seq. 
 ^Phll. Mag. vol. xxxvi. p. 102, and Hi. p. 186. 
 
380 Whitekurst on Stratigraphy 
 
 narrow slips, and lying parallel to the greatest rise of 
 any long ridge of mountains ; and so, in fact, we find 
 them." 
 
 Contrast this clear presentation of the tectonic 
 structure of our mountains and continents with the 
 confused and contradictory explanation of the same 
 structure subsequently promulgated from Freiberg. 
 Michell clearly realised that the rocks of the earth's 
 crust had been laid down in a definite order, that 
 they had been uplifted along the mountain axes, 
 that they had been subsequently planed down, and 
 that their present disposition in parallel bands was 
 the result partly of the upheaval and partly of the 
 denudation. 
 
 Another English observer, whose name may be 
 mentioned here, is John Whitehurst (1713-1788) who 
 published in 1778 an "Inquiry into the Original 
 State and Formation of the Earth." This work was 
 the last effort of the fantastic English School of 
 Cosmogonists. Amid absurd speculations as to the 
 condition of Chaos and other equally visionary topics, 
 he wrote well on organic remains, and showed that he 
 clearly grasped the stratigraphical succession of the 
 formations in Derbyshire and other parts of England. 
 " The strata invariably follow each other," he remarks, 
 u as it were, in alphabetical order," and though they 
 may not be alike in all parts of the earth, neverthe- 
 less, " in each particular part, how much soever they 
 may differ, yet they follow each other in a regular 
 succession." 
 
 While the stratigraphical sequence of the geological 
 formations in England was thus partially realised by 
 
William Smith, Father of English Geology 3 8 1 
 
 a few pioneers, its final establishment was the work 
 of William Smith (1769-1839) usually known as 
 the " Father of English geology." He definitely 
 arranged the rocks in their true order from the Killas 
 series (Cambrian and Silurian) of Wales up to the 
 Tertiary groups of the London basin. More particu- 
 larly he determined the subdivisions of the Secondary, 
 or at least of the Jurassic (Oolitic) rocks, and estab- 
 lished their order, which has been found applicable 
 not only to England but to the rest of Europe. 
 No more interesting chapter in scientific annals can 
 be found than that which traces the progress of this 
 remarkable man, who, amidst endless obstacles and 
 hindrances, clung to the idea which had early taken 
 shape in his mind, and who lived to see that idea 
 universally accepted as the guiding principle in the 
 investigation of the geological structure, not of Eng- 
 land only, but of Europe and of the globe. 
 
 William Smith came of a race of yeoman farmers 
 who for many generations had owned small tracts of 
 land in Oxfordshire and Gloucestershire. 1 He was 
 born at Churchill, in the former county, on 23rd March 
 1769, the same year that gave birth to Cuvier. 
 Before he was eight years old he lost his father. 
 After his mother married for the second time, he 
 seems to have been largely dependent upon an uncle 
 
 1 The biographical details are derived from the Memoirs of William 
 Smith, LL.D., by his nephew and pupil, John Phillips, 1844. The 
 biographer (1800-1874) became himself a leading geologist in 
 England and for the last eighteen years of his active and useful life 
 was the genial Reader and Professor of Geology in the University 
 of Oxford. 
 
382 William Smith 
 
 for education and assistance. The instruction obtain- 
 able at the village school was of the most limited 
 kind. With difficulty the lad procured means to 
 purchase a few books from which he might learn the 
 rudiments of geometry and surveying. Already he 
 had taken to the observing and collecting of stones, 
 particularly of the well-preserved fossils whereof the 
 Jurassic rocks of his neighbourhood were full. He 
 came to be interested in questions of drainage and 
 other pursuits connected with the surface of the land, 
 and in spite of want of encouragement, made such 
 progress with his studies that at the age of eighteen 
 he was taken as assistant to a surveyor. But he had 
 no education beyond that of the village school and 
 what he had been able to acquire through his own 
 reading. This early defect crippled, to the end of 
 his life, his efforts to make known to the world the 
 scientific results he obtained. 
 
 Smith's capacity and steady powers of application were 
 soon appreciated in the vocation upon which he had 
 entered. Before long he was entrusted with all the 
 ordinary work of a land surveyor, to which were 
 added many duties that would now devolve upon a 
 civil engineer. From an early part of his professional 
 career, his attention was arrested by the great variety 
 among the soils with which he had to deal, and the 
 connection between these soils and the strata under- 
 lying them. He had continually to traverse the red 
 ground that marks the position of the Triassic marls 
 and sandstones in the south-west and centre of 
 England, and to pass thence across the clays and 
 limestones of the Lias, or to and fro among the 
 
His early Geological studies 383 
 
 freestones and shales of the Oolites. The contrasts 
 of these different kinds of rock, the variations in 
 their characteristic scenery, and the persistence of 
 feature which marked each band of strata gave him 
 constant subjects of observation and reflection. 
 
 By degrees his surveying duties took him farther 
 afield, and brought him in contact with yet older forma- 
 tions, particularly with the Coal-measures of Somerset 
 and their dislocations. At the age of four-and-twenty, 
 he was engaged in carrying out a series of levellings 
 for a canal, and had the opportunity of confirming 
 a suspicion, which had been gradually taking shape 
 in his mind, that the various strata with which he 
 was familiar, though they seemed quite flat, were 
 really inclined at a gentle angle towards the east, and 
 terminated sharply towards the west, like so many 
 " slices of bread and butter." He took the liveliest 
 interest in this matter, and felt convinced that it 
 must have a far deeper meaning and wider application 
 than he had yet surmised. 
 
 His first start on geological exploration took place 
 the following year (1794) when, as engineer to a canal 
 that was to be constructed, he was deputed to accom- 
 pany two of the Committee of the Company in a 
 tour of some weeks duration, for the purpose of 
 gaining information respecting the construction, man- 
 agement, and trade of other lines of inland navigation. 
 The party went as far north as Newcastle, and came 
 back through Shropshire and Wales to Bath, having 
 travelled 900 miles on their mission. The young 
 surveyor made full use of the opportunities which this 
 journey afforded him. He had by this time satisfied 
 
384 William Smith 
 
 himself that the stratigraphical succession, which he 
 had worked out for a small part of the south-west 
 of England, had an important bearing on scientific 
 questions, besides many practical applications of im- 
 portance. But it needed to be extended and checked 
 by a wider experience. u No journey, purposely con- 
 trived," so he wrote, " could have better answered 
 my purpose. To sit forward on the chaise was a 
 favour readily granted ; my eager eyes were never 
 idle a moment ; and post-haste travelling only put 
 me upon new resources, General views, under exist- 
 ing circumstances, were the best that could have been 
 taken, and the facility of knowing, by contours and 
 other features, what might be the kind of stratification 
 in the hills is a proof of early advancement in the 
 generalisation of phenomena. 
 
 " In the more confined views, where the roads 
 commonly climb to the summits, as in our start from 
 Bath to Tetbury, by Swanswick, the slow driving 
 up the steep hills afforded me distinct views of the 
 nature of the rocks ; rushy pastures on the slopes 
 of the hills, the rivulets and kind of trees, all aided 
 in defining the intermediate clays ; and while occasion- 
 ally walking to see bridges, locks, and other works, 
 on the lines of canal, more particular observations 
 could be made. 
 
 " My friends being both concerned in working coal, 
 were interested in two objects ; but I had three, and 
 the most important one to me I pursued unknown 
 to them ; though I was continually talking about 
 the rocks and other strata, they seemed not desirous 
 of knowing the guiding principles or objects of these 
 
Early geological tour 385 
 
 remarks ; and it might have been from the many 
 hints, perhaps mainly on this subject, which I made 
 in the course of the journey, that Mr. Palmer jocosely 
 recommended me to write a book of hints." 1 
 
 We can picture the trio on this memorable 
 journey the young man in front eagerly scrutinizing 
 every field, ridge, and hill along each side of the 
 way, noting every change of soil and topography, 
 and turning round every little while, unable to 
 restrain his exuberant pleasure as his eye detected 
 one indication after another of the application of the 
 principles he had found to hold good at home, and 
 pointing them out with delight to his two sedate 
 companions, who looked at him with amusement, 
 but with neither knowledge of his aims nor sympathy 
 with his enthusiasm. 
 
 For six years William Smith was engaged in setting 
 out and superintending the construction of the Somer- 
 setshire Coal Canal. In the daily engrossing cares of 
 these duties it might seem that there could be little 
 opportunity for adding to his stores of geological 
 knowledge, or working out in more detail the prin- 
 ciples of stratigraphy that he had already reached. 
 But in truth these six years were among the most 
 important in his whole career. The constant and 
 close observation which he was compelled to give to 
 the strata that had to be cut through in making the 
 canal, led him to give more special attention to the 
 organic remains in them. From boyhood he had 
 gathered fossils, but without connecting them definitely 
 with the succession of the rocks that contained them. 
 1 Memoirs, p. 10. 
 
386 William Smith 
 
 He now began to observe more carefully their dis- 
 tribution, and came at last to perceive that, certainly 
 among the formations with which he had to deal, 
 "each stratum contained organized fossils peculiar to 
 itself, and might, in cases otherwise doubtful, be 
 recognized and discriminated from others like it, but 
 in a different part of the series, by examination of 
 them." 1 
 
 It was while engaged in the construction of this 
 canal that Smith began to arrange his observations 
 for publication. He had a methodical habit of writ- 
 ing out his notes and reflections, and dating them. 
 But he had not the art of condensing his material, 
 and arranging it in literary form. Nevertheless, he 
 could not for a moment doubt that the results which 
 he had arrived at would be acknowledged by the 
 public to possess both scientific importance and prac- 
 tical value. Much of his work was inserted upon 
 maps, wherein he traced the position and range of 
 each of the several groups of rock with which he had 
 become familiar. He had likewise ample notes of 
 local sections, and complete evidence of a recognis- 
 able succession among the rocks. Not only could he 
 identify the strata by their fossils, but he could point 
 out to the surveyors, contractors, and other practical 
 men with whom he came in contact, how useful in 
 many kinds of undertakings was the detailed know- 
 ledge which he had now acquired. In agriculture, 
 in mining, in road-making, in draining, in the con- 
 struction of canals, in questions of water-supply, and 
 in many other affairs of everyday life, he was able 
 1 Memoirs, p. 1 5 . 
 
As Engineer and Surveyor 387 
 
 to prove that his system of observation possessed 
 great practical utility. 
 
 In the year 1799, n ^ s connection with the Canal 
 Company came to an end. He was thereafter com- 
 pelled to put his geological knowledge to commercial 
 use, and to undertake the laborious duties of an 
 engineer and surveyor on his own account. Eventually 
 he found considerable employment over the whole 
 length and breadth of England, and showed singular 
 shrewdness and originality in dealing with the engineer- 
 ing questions which came before him. He was a 
 close observer of nature, and his knowledge of natural 
 processes stood him in good stead in his professional 
 calling. If he had to keep out the sea from low 
 ground, he constructed his barrier as nearly as possible 
 like those which the waves themselves had thrown up. 
 If he was asked to prevent a succession of landslips, 
 he studied the geological structure of the district and 
 the underground drainage, and drove his tunnels so 
 as to intercept the springs underneath. His nephew 
 and biographer tells us that his engagements in con- 
 nection with drainage and irrigation involved journeys 
 of sometimes 10,000 miles in a year. 
 
 Such continuous travelling to and fro across the 
 country served to augment enormously his minute 
 personal acquaintance with the geological structure of 
 England. He made copious notes, and his retentive 
 memory enabled him to retain a vivid recollection 
 even of the details of what he had once seen. But 
 the leisure which he needed in order to put his 
 materials together seemed to flee from him. Year 
 after year passed away ; the pile of manuscript rose 
 
388 William Smith 
 
 higher, but no progress was made in the preparation 
 of the growing mass of material for publication. 
 
 In the year 1799, William Smith made the acquaint- 
 ance of the Rev. Benjamin Richardson, who, living in 
 Bath, had interested himself in forming a collection of 
 fossils from the rocks of the neighbourhood. Look- 
 ing over this collection, the experienced surveyor was 
 able to tell far more about its contents than the owner 
 of it knew himself. Writing long afterwards to Sedg- 
 wick, Mr. Richardson narrated how Smith could decide 
 at once from what strata they had respectively come, 
 and how well he knew the lie of the rocks on the 
 ground. " With the open liberality peculiar to Mr. 
 Smith," he adds, " he wished me to communicate this 
 to the Rev. J. Townsend of Pewsey (then in Bath), 
 who was not less surprised at the discovery. But we 
 were soon much more astonished by proofs of his own 
 collecting, that whatever stratum was found in any 
 part of England, the same remains would be found in 
 it and no other. Mr. Townsend, who had pursued the 
 subject forty or fifty years, and had travelled over the 
 greater part of civilized Europe, declared it perfectly 
 unknown to all his acquaintance, and, he believed, 
 to all the rest of the world. In consequence of 
 Mr. Smith's desire to make so valuable a discovery 
 universally known, I without reserve gave a card of 
 the English strata to Baron Rosencrantz, Dr. Mailer 
 of Christiania, and many others, in the year iBoi." 1 
 
 The card of the English strata referred to in this 
 letter was a tabular list of the formations from the Coal 
 up to the Chalk, with the thicknesses of the several 
 1 Memoirs, p. 31. 
 
His original Table of Strata 389 
 
 members, an enumeration of some of their characteristic 
 fossils, and a synopsis of their special lithological 
 peculiarities and scenery. This table was drawn up 
 in triplicate by Mr. Richardson, at Smith's dictation, 
 in the year 1799, each of the friends and Mr. Towns- 
 end taking a copy. Smith's copy was presented by 
 him to the Geological Society of London in 1831. 
 
 Though not actually published, this table obtained 
 wide publicity. It showed that the fundamental prin- 
 ciples of stratigraphy had been worked out by William 
 Smith alone, and independently, before the end of the 
 eighteenth century. He had demonstrated, as his 
 friend and pupil Farey testified, " that the fossil pro- 
 ductions of the strata are not accidentally distributed 
 therein, but that each particular species has its proper 
 and invariable place in some particular stratum ; and 
 that some one or two or more of these species of fossil 
 shells may serve as new and more distinctive marks of 
 the identity of most of the strata of England/' 1 Had 
 Smith's table been printed and sold it would have 
 established his claim to priority beyond all possibility of 
 cavil. But even without this technical support, his 
 place among the pioneers of stratigraphy cannot be 
 gainsaid. 
 
 Notwithstanding the abundant professional employ- 
 ment which he obtained, Smith never abounded in 
 money. So keenly desirous was he to complete his 
 investigation of the distribution of the strata of Eng- 
 land, for the purpose of constructing a map of the 
 country, that he spent as freely as he gained, walking, 
 riding, or posting in directions quite out of the way 
 
 1 See note on p. 394. 
 
39 William Smith 
 
 of his business. " Having thus emptied his pockets 
 for what he deemed a public object, he was forced to 
 make up, by night-travelling, the time he had lost, so 
 as not to fail in his professional engagements." 
 
 Stimulated by the kindly urgency of his friend 
 Richardson, who alarmed him by pointing out that if 
 he did not publish his observations, some one else 
 might anticipate him, Smith was prevailed upon to draw 
 up a prospectus of a work in which he proposed to give 
 a detailed account of the various strata of England and 
 Wales, with an accompanying map and sections. A 
 publisher in London was named, and the prospectus 
 was extensively circulated ; but it led to nothing. 
 
 Eventually Smith established himself in London as 
 the best centre for his professional work, and in 1805 
 he took a large house there, with room for the display 
 of his collections and maps, which were open to the 
 inspection of any one interested in such matters. 
 Among his materials he had completed a large county 
 map of Somersetshire, as a specimen of what might 
 be done for the different counties of England. This 
 document seems to have been exhibited at the Board 
 of Agriculture, and a proposal was made that he should 
 be permanently attached to the corps of engineers then 
 engaged in surveying the island. But the idea never 
 went farther. Not until thirty years later was it re- 
 vived by De la Beche, and pressed with such persever- 
 ance as to lead in the end to the establishment of the 
 present Geological Survey of Great Britain. 
 
 From 1799, when Smith first contemplated the pub- 
 lication of his observations, every journey that he 
 took was as far as possible made subservient to the 
 
His geological Map of England 391 
 
 completion of his map of England. At last, but not 
 until the end of the year 1812, he found a publisher 
 enterprising enough to undertake the risk of engrav- 
 ing and publishing this map. The work was begun in 
 January 1813, and was published in August I8I5- 1 
 It was appropriately dedicated to Sir Joseph Banks, 
 President of the Royal Society, who had encouraged 
 and helped the author. 
 
 William Smith's map has long since taken its place 
 among the great classics of geological cartography. It 
 was the first attempt to portray on such a scale not 
 merely the distribution, but the stratigraphy of the 
 formations of a whole country. Well might D'Au- 
 buisson say of it that " what the most distinguished 
 mineralogists during a period of half a century had 
 done for a little part of Germany, had been undertaken 
 and accomplished for the whole of England by one 
 man ; and his work, as fine in its results as it is 
 astonishing in its extent, demonstrates that England is 
 regularly divided into strata, the order of which is 
 never inverted, and that the same species of fossils 
 are found in the same stratum even at wide distances."' 
 
 But it is not so much as a cartographical achieve- 
 ment that Smith's great map deserves our attention 
 at present. Its appearance marked a distinct epoch 
 in stratigraphical geology, for from that time some of 
 what are now the most familiar terms in geological 
 nomenclature passed into common use. Smith had no 
 scholarship ; he did not even cull euphonious terms 
 
 1 For the title and description of the map see p. 452, where refer- 
 ence will be found to the map of G. B. Greenough. 
 
 2 Tralte de Geognosit (1819), tome ii. p. 253. 
 
39 2 William Smith 
 
 from Greek or Latin lexicons ; he was content to take 
 the rustic or provincial names he found in common 
 use over the districts which he traversed. Hence were 
 now introduced into geological literature such words 
 as London Clay, Kentish Rag, Purbeck Stone, Car- 
 stone, Cornbrash, Clunch Clay, Lias, Forest Marble. 
 
 By ingeniously colouring the bottom of each forma- 
 tion a fuller tint than the rest, Smith brought the 
 general succession of strata conspicuously before the 
 eye. Further, by the aid of vertical tables of the 
 formations and a horizontal section from Wales to 
 the vale of the Thames, he was able to give the details 
 of the succession which, for some twenty-four years, 
 he had been engaged in unravelling in every part of 
 the kingdom. 
 
 Of especial value and originality was his clear sub- 
 division of what is now known as the Jurassic system. 
 He did for that section of the geological record what 
 Cuvier and Brongniart had done for the Tertiary series 
 of Paris. After the first copies of the map had been 
 issued, he was able still further to subdivide and 
 improve his classification of these strata, introducing 
 among the new bands, Crag, Portland Rock, Coral 
 Rag, and Kellaways Stone. 1 
 
 In the memoir accompanying the map, the tabular 
 arrangement of the strata drawn up in 1799 was 
 inserted, with its column giving the names, so far as 
 he knew them, of the more characteristic fossils of 
 each formation. 
 
 To the laborious researches of William Smith we 
 are thus indebted for the first attempt to distinguish 
 1 Phillips, Memoirs, p. 146. 
 
His professional reverses 393 
 
 the various subdivisions of the Secondary rocks, from 
 the base of the New Red Sandstone up to the Chalk,, 
 and for the demonstration that these successive plat- 
 forms are marked off from each other, not merely 
 by mineral characters, but by their peculiar assemblages 
 of organic remains. From his provincial terminology 
 come the more sonorous names of Purbeckian, Port- 
 landian, Callovian, Corallian, Bathonian, Liassic, which 
 are now familiar words in every geological text-book. 
 In his eagerness to make his map as complete and 
 accurate as was possible to him, Smith spent so freely 
 of his hardly-earned income that he accumulated no 
 savings against the day of trial, which came only too 
 soon. He had been induced to lay down a railway 
 on a little property which early in life he had purchased 
 near Bath, with the view of opening some new quarries 
 and bringing the building-stone to the barges on the 
 canal. Unfortunately the stone, on the continuance 
 and quality of which the whole success of the enter- 
 prise rested, failed. It became necessary to sell the 
 property, and thereafter the sanguine engineer was 
 left with a load of debt under which most men would 
 have succumbed. Struggling under this blow, he was 
 first compelled to part with his collections of fossils, 
 which were acquired by the Government and placed 
 in the British Museum. Next he found himself no 
 longer able to bear the expense of the house in London 
 which he had occupied for fifteen years. Not only 
 so, but hard fate drove him to sell all his furniture, 
 books and other property, keeping only the maps, 
 sections, drawings and piles of manuscript which were 
 so precious in his own eyes, but for which nobody 
 
394 William Smith 
 
 would have been likely to give him anything. For 
 seven years he had no home, but wandered over the 
 north of England, wherever professional engagements 
 might carry him. His income was diminished and 
 fluctuating, yet even under this cloud of trial he 
 retained his quiet courage and his enthusiasm for 
 geological exploration. 
 
 That a man of Smith's genius should have been 
 allowed to remain in this condition of toil and poverty 
 has been brought forward as a reproach to his fellow- 
 countrymen. It may be doubted, however, whether 
 a man of his strong independence of character would 
 have accepted any pecuniary assistance, so long as 
 he could himself gain by his own exertions a modest 
 though uncertain income. It is not that his merits 
 were unrecognised in England, though perhaps the 
 appreciation of them was tardier than it might have 
 been. In 1818 a full and generous tribute to his 
 merits was written by Fitton, and appeared in the 
 Edinburgh Review for February in that year. 1 But 
 though his fame was thus well established, his financial 
 position remained precarious. He had gradually 
 formed a consulting practice as a mineral and geo- 
 logical surveyor in the north of England, and he 
 
 1 At the end of 1817 there seems to have been some inquiry 
 as to priority of discovery in regard to Smith's work. In the 
 following March, Mr. John Farey contributed to Tilloch's Philo- 
 sophical Magazine a definite statement of Smith's claims, showing 
 that the fundamental facts and principles he had established had 
 been freely made known by him to many people as far back as 
 1795, and that Farey himself, on 5th August 1 807, had published 
 an explicit notification of Smith's discoveries and conclusions as 
 to fossil shells in the article on Coal in Rees' Cyclopedia. 
 
His figure and character 395 
 
 eventually settled at Scarborough. From 1828 to 
 1834 he acted as land-steward on the estate of 
 Hackness in the same district of Yorkshire. In 
 1831 he received from the Geological Society the 
 first Wollaston Medal, and the President of the 
 Society, Adam Sedgwick, seized the occasion to pro- 
 claim, in fervid and eloquent words, the admiration 
 and gratitude of all the geologists of England towards 
 the man whom he named " the father of English 
 geology." Next year a pension of jioo from the 
 Crown was conferred upon him. Honours now came 
 to him in abundance. But his scientific race was 
 run. He continued to increase his piles of manu- 
 script, but without methodically digesting them for 
 publication. He died on 28th August 1839, m t ^ ie 
 seventy-first year of his age. 
 
 William Smith was tall and broadly built, like the 
 English yeomen from whom he came. His face 
 was that of an honest, sagacious farmer, whose broad 
 brow and firm lips betokened great capacity and 
 decision, but would hardly have suggested the enthusi- 
 astic student of science. His work, indeed, bears 
 out the impression conveyed by his portrait. His 
 plain, solid, matter-of-fact intellect never branched 
 into theory or speculation, but occupied itself wholly 
 in the observation of facts. His range of geological 
 vision was as limited as his general acquirements. He 
 had reached early in life the conclusions on which 
 his fame rests, and he never advanced beyond them. 
 His whole life was dedicated to the task of extending 
 his stratigraphical principles to every part of England. 
 But this extension, though of the utmost importance 
 
396 William Smith 
 
 to the country in which he laboured, was only of 
 secondary value in the progress of science. 
 
 Besides his great map of England, Smith published 
 also a series of geological maps, on a larger scale, of 
 the English counties, comprising in some instances 
 much detailed local information. He likewise issued 
 a series of striking horizontal sections (1819) across 
 different parts of England, in which the succession 
 of the formations was clearly depicted. These sections 
 may be regarded as the complement of his map, 
 and as thus establishing for all time the essential 
 features of English stratigraphy, and the main out- 
 lines of the sequence of the Secondary formations 
 for the rest of Europe. In another publication, Strata 
 Identified by Organised Fossils (1816), he gave a series 
 of plates, with excellent engraved figures of charac- 
 teristic fossils from the several formations. He 
 adopted in this work the odd conceit of having the 
 plates printed on variously coloured paper, to corre- 
 spond with the prevalent tint of the strata from 
 which the fossils came. He had no palaeontological 
 knowledge, so that the thin quarto, never completed, 
 is chiefly of interest as a record of the organisms 
 that he had found most useful in establishing the 
 succession of the formations. 
 
 There is yet another name that deserves to be 
 remembered in any review of the early efforts to group 
 the Secondary formations that of Thomas Webster 
 (I773-I844). 1 As far back as 181 1, this clever artist 
 
 1 Webster was born in the Orkney Islands, received his education 
 at Aberdeen, and came early in life to London. He practised as an 
 architect, and made journeys in England during which he devoted 
 
Webster 397 
 
 and keen-eyed geologist began a series of investiga- 
 tions of the coast-sections of the Isle of Wight and 
 of Dorset, and continued them for three years. They 
 were published in 1815, the same year that Smith's 
 map made its appearance. 1 They were thus indepen- 
 dent of that work. Webster had already studied the 
 Tertiary formations of the Isle of Wight and had pub- 
 lished a remarkable memoir upon them in which he 
 recognised their alternations of fresh-water and marine 
 strata, 2 as had been done in the Paris basin. He now 
 threw into tabular arrangement the whole succession of 
 strata from the upper fresh-water (Oligocene) group 
 through the Lower Tertiary series to the Kimmeridge 
 shale in the Jurassic system. He clearly defined each 
 of the leading subdivisions of the Cretaceous series, 
 and prepared the way for the admirable later and more 
 detailed work of William Henry Fitton (i78o-i86i) 3 
 
 much time to geological enquiry. In 1826 he became House-secre- 
 tary and Curator to the Geological Society, and in 1841 was appointed 
 Professor of Geology in University College, London. 
 
 iSee Englefield's Isle of Wight (1815), p. 117. 
 
 2 Trans. Geol. Soc. vol. ii. This and his other memoirs are classic 
 contributions to the Secondary and Tertiary geology of England. 
 
 3 Fitton, though of English lineage, was born in Dublin. After 
 distinguishing himself at Trinity College there, he at first proposed to 
 enter the church, but his predilection for natural science turned him 
 into medicine, and he finally took the degree of M.D. and for some 
 years practised as a physician in Northampton. Early in life he 
 studied at Edinburgh, and acquired there under Jameson a love of 
 geological pursuits. Eventually, having married a lady possessed of 
 ample means, he retired from his profession, and established himself 
 in London, where his house became one of the scientific centres of his 
 time. From 1817 down to the middle of last century he continued 
 at intervals to contribute articles to the Edinburgh Review on the 
 
398 Geological Society of London 
 
 to whom we are indebted for the first detailed and 
 accurate determination of the succession of strata and 
 their distinctive fossils, from the base of the Chalk 
 down into the Oolites, in the south of England and 
 the neighbouring region in France. More particularly 
 he showed the relations and importance of the Green- 
 sand formations, his memoirs on which are now among 
 the classics of English geology. 
 
 In concluding this sketch of the early progress of 
 stratigraphical geology in Britain I may refer to the 
 important influence exerted by the Geological Society 
 of London which was founded in 1 807 " to investigate 
 the mineral structure of the Earth." At that time the 
 warfare between the Neptunists and Plutonists still 
 continued, but there were many men, interested in the 
 study of geological subjects, who were weary of the 
 conflict of hypotheses, and who would fain devote their 
 time and energy to the accumulation of facts regard- 
 ing the ancient history of the globe, rather than to 
 the elaboration of theories to explain them. A few 
 such enquirers formed themselves into the Geological 
 Society, and soon attracted others around them until, 
 in a few years, they had established an active insti- 
 tution which became a centre for geological research 
 and discussion, published the contributions of its 
 
 progress of his favourite science. These essays showed him to be an 
 able and elegant writer, who was not only conversant with all the 
 advances in the geology of the day, but having also an intimate 
 acquaintance with the history and literature of the science, was able 
 by his criticism to exercise a guiding influence on his contemporaries. 
 His researches among the Greensand formations, on which his fame 
 rests as an original observer, were continued for twelve years from 
 1824 to 1836. 
 
Cony b ear e and Phillips 399 
 
 members in quarto volumes, and eventually was 
 incorporated by Royal Charter as one of the leading 
 scientific bodies of the country. This society, which 
 has been the parent of others in different countries, 
 continues to flourish, and its publications, extending 
 over nearly a century, contain a record of original 
 researches which have powerfully helped the progress 
 of all branches of geology. Besides their papers issued 
 by the society, some of the early members published 
 separate works which greatly advanced the cause of 
 their favourite science. Among these early inde- 
 pendent treatises perhaps the most important was the 
 Outlines of the Geology of England and Wales by 
 W. D. Conybeare (1787-1857) and W. Phillips 
 (1775-1828) which appeared in 1822. In this excel- 
 lent volume all that was then known regarding the 
 rocks of the country, from the youngest formations 
 down to the Old Red Sandstone, was summarised in so 
 clear and methodical a manner as to give a powerful 
 impulse to the cultivation of geology in England. 
 
 From the outline given in this and the previous 
 Chapter, it will be seen that during the last two 
 decades of the eighteenth and the first four of the 
 nineteenth century, great progress was made in the 
 study of the stratigraphy of the Secondary and Tertiary 
 formations of France and England, while the principle 
 of the application of the evidence of organic remains 
 to the identification of these formations from district 
 to district was everywhere applied with signal success. 
 From the youngest alluvial deposits down through 
 the whole series of sedimentary rocks to the Car- 
 boniferous system, the clue had been obtained and 
 
400 Rapid growth of Stratigraphy 
 
 put to use whereby the stratigraphical order could 
 be satisfactorily established from one country to 
 another. A prodigious impetus was now given to 
 the study of geology. The various stratified forma- 
 tions, arranged in their true chronological sequence, 
 were seen to contain the regular and decipherable 
 records of the history of our globe, which could be 
 put together with at least as much certainty as 
 faded manuscripts of human workmanship. The or- 
 ganic remains contained in them were found to be 
 not random accumulations, heaped together by the 
 catastrophes of bygone ages, but orderly chronicles of 
 old sea-floors, lake-bottoms, and land-surfaces. The 
 centre of gravity of geology was now rapidly altered, 
 especially in Western Europe. Minerals and rocks no 
 longer monopolized the attention of those who inter- 
 ested themselves in the crust of the earth. The petri- 
 fied remains of former plants and animals ceased to be 
 mere curiosities. Their meaning as historical docu- 
 ments was at last realised. They were seen to have a 
 double interest, for while they told the story of the 
 successive vicissitudes which the surface of the earth 
 had undergone, from remote ages down to the present, 
 they likewise unfolded an altogether new and mar- 
 vellous panorama of the progress of life upon that 
 surface. They had hitherto shared with minerals and 
 rocks the usage of the term " fossil." As their im- 
 portance grew, they were discriminated as " organized 
 fossils." But the rising tide of awakened interest, follow- 
 ing Lamarck's lead, swept away the qualifying participle, 
 and organic remains became sole possessors of the 
 term, as if they were the only objects dug out of the 
 
Geological Text-Books 401 
 
 earth that were any longer worthy to be denominated 
 fossils. 
 
 While the whole science of geology made gigantic 
 advances during the nineteenth century, by far the most 
 astonishing progress sprang from the recognition of the 
 value of fossils. To that source may be traced the 
 prodigious development of stratigraphy over the whole 
 world, the power of working out the geological history 
 of a country, and of comparing it with the history of 
 other countries, the possibility of tracing the synchron- 
 ism and the sequence of the geographical changes of 
 the earth's surface since life first appeared upon the 
 planet. To the same source, also, we are indebted for 
 the rise of the science of Palaeontology, and the splendid 
 contributions it has made to biological investigation. 
 In the midst of the profusion, alike of blossom and of 
 /fruit, let us not forget the work of those who sowed 
 ^*the seed of the abundant harvest which we are now 
 reaping. Let us remember the early suggestive essays 
 of Guettard, the pregnant ideas of Lehmann and 
 Fiichsel, the prescient pages of Giraud-Soulavie, the 
 brilliant work of Lamarck, Cuvier and Brongniart, and 
 the patient and clear-sighted enthusiasm of William 
 Smith. 
 
 To another feature in the rapid advance of geology 
 after these pioneers had gone to their rest, brief allusion 
 must here be made. The amount of ascertained fact 
 regarding the structure and history of the earth was 
 every year increasing at so rapid a rate that it became 
 necessary to prepare digests of it, for the use of those 
 who wished to be informed on these subjects or to 
 keep pace with the advance of knowledge. Hence 
 
 2 c 
 
402 Geological Text-Books 
 
 arose in different countries, text-books, manuals and 
 other general treatises wherein an account was given of 
 the facts and principles of geological science. The 
 earlier works of this kind were in some cases a mere 
 reproduction of the system taught by Werner at Frei- 
 berg. Such were the Lehrbuch der Mineralogie (1801- 
 1803) of F. A. Reuss and the Treatise on Geognosy 
 (1808) by R. Jameson which formed the third volume 
 of the first edition of his System of Mineralogy. The 
 citations which have been made in Chapter VII. from 
 the Edinburgh Professor's volume may serve as illus- 
 trations of the Wernerian geognosy. But the great 
 advance made by the science during the first three 
 decades of last century, consequent on the development 
 of stratigraphy and the construction of geological maps 
 led to a complete change in the method of treatment 
 adopted in the text-books. In the excellent Traite de 
 Geognosie of J. F. d'Aubuisson de Voisons the transition 
 from Neptunianism to more modern and scientific views 
 is well displayed. In Germany various treatises ap- 
 peared in which the newer developments of geology 
 were discussed, the most voluminous and exhaustive 
 being the admirable Lehrbuch of C. F. Naumann. In 
 Belgium the JLUmem de Geologic of Omalius d'Halloy 
 and his Abrege went through successive editions, and did 
 good service in spreading a knowledge of the science. 
 In Italy the works of Breislak already cited (p. 257) 
 especially his Institutions Geologiques (Milan and Paris 
 1818) were useful additions to geological literature. 
 
 In England the Outlines of Conybeare and Phillips, 
 already noticed, deserves a special commendation. 
 Nine years later the Manual of Geology by H. T. 
 
Lyell's Influence 403 
 
 De la Beche appeared (1831) and at once established 
 for itself a world-wide reputation for its ample and 
 clear presentation of the science. It was translated 
 into French and German, and an edition of it -was 
 also published in the United States. De la Beche's 
 other works, more particularly his Researches in Theo- 
 retical Geology (1831) and his How to observe in 
 Geology (1835), which showed his remarkable range 
 of acquirement, his scientific insight and his wide 
 practical acquaintance with rocks in the field, were 
 important contributions to the science. But of all the 
 English writers of general treatises on geology, the first 
 place must undoubtedly be assigned to Charles Lyell 
 (1797-1875) who exercised a profound influence on the 
 geology of his time in all English-speaking countries. 
 Adopting the principles of the Huttonian theory, he 
 developed them until the original enunciator of them 
 was nearly lost sight of. With unwearied industry he 
 marshalled in admirable order all the observations that 
 he could collect in support of the doctrine that the 
 present is the key to the past. With inimitable luci- 
 dity he traced the operation of existing causes, and 
 held them up as the measure of those which have acted 
 in bygone time. He carried Hutton's doctrine to its 
 logical conclusion, for not only did he refuse to allow 
 the introduction of any process which could not be 
 shown to be a part of the present system of Nature, he 
 would not even admit that there was any reason to 
 suppose the degree of activity of the geological agents 
 to have ever seriously differed from what it has been 
 within human experience. He became the great high 
 priest of Uniformitarianism a creed which grew to be 
 
404 Charles Lyell 
 
 almost universal in England during his life, but which 
 never made much way in the rest of Europe, and which 
 in its extreme form is probably now held by few geolo- 
 gists in any country. Lyell's Principles of Geology will, 
 however, always rank as one of the classics of geology, 
 and must form an early part of the reading of every 
 man who would wish to make himself an accomplished 
 geologist. The last part of this work was ultimately 
 published as a separate volume, with the title of 
 Elements of Geology^ in which a large space was devoted 
 to an account of the stratified fossiliferous formations. 
 This treatise, diligently kept up to date by its author, 
 continued during his life-time to be the chief English 
 exposition of its subject, and the handbook of every 
 English geologist. 
 
 Lyell's function was mainly that of a critic and 
 exponent of the researches of his contemporaries, and 
 of a philosophical writer thereon, with a rare faculty of 
 perceiving the connection of scattered facts with each 
 other, and with the general principles of science. As 
 Ramsay once remarked to me, " We collect the data, 
 and Lyell teaches us to comprehend the meaning of 
 them." But Lyell, though he did not, like Sedgwick 
 and Murchison, add new chapters to geological history, 
 nevertheless left his mark upon the nomenclature and 
 classification of the geological record. Conceiving, as 
 far back as 1828, the idea of arranging the whole series 
 of Tertiary formations in four groups, according to their 
 affinity to the living fauna, he established, in conjunction 
 with Deshayes, who had independently formed a similar 
 opinion, the well-known classification into Eocene, 
 Miocene, and Pliocene. The first of these terms was 
 
His Tertiary Classification 405 
 
 proposed for strata containing an extremely small pro- 
 portion of living species of shells ; the second for those 
 where the percentage of recent species was considerable, 
 but still formed the minority of the whole assemblage, 
 while the third embraced the formations in which living 
 forms were predominant. The scheme was a somewhat 
 artificial one, and the original percentages have had to 
 be modified from time to time, but the terms have 
 kept their place, and are now firmly planted in the 
 geological language of all corners of the globe. 
 
CHAPTER XIII 
 
 PROGRESS of Stratigraphical Geology The Transition or Greywacke 
 formation resolved by Sedgwick and Murchison into the Cam- 
 brian, Silurian and Devonian systems. The Primordial Fauna 
 of Barrande. The pre-Cambrian rocks first begun to be set 
 in order by Logan. 
 
 THE determination of the value of fossils as chrono- 
 logical documents has done more than any other 
 discovery to change the character and accelerate the 
 progress of geological inquiry. No contrast can be 
 more striking than the difference between the con- 
 dition of the science before and after that discovery 
 was made. Before that time, while the Wernerian 
 classification of the rocks of the earth's crust prevailed, 
 there was really little stimulus to investigate these 
 rocks in their chronological relations to each other. 
 They were grouped, indeed, in a certain order, which 
 was believed to express their succession in time, but 
 their identification from one country to another pro- 
 ceeded on no minute study of their internal structure, 
 their fossil contents, or their tectonic relations. It 
 was thought enough if their mineral characters were 
 determined so that they could be placed in one or 
 other of the divisions of the Freiberg system. Hence, 
 
Influence of Fossils on Stratigraphy 407 
 
 as was pointed in an earlier chapter, when an orthodox 
 disciple of Werner had relegated a mass of deposits 
 to the Transition series, or the Floetz or the Inde- 
 pendent Coal-formation, as the case might be, he 
 considered that all that was really essential had been 
 ascertained, and his interest in the matter came practi- 
 cally to an end. 
 
 But the extraordinary awakening which resulted from 
 the labours of Soulavie, Lamarck, Cuvier, Brongniart 
 and William Smith, invested the strata with a new 
 meaning. As stratigraphical investigations multiplied, 
 the artificiality and inadequacy of the Wernerian 
 arrangement became every day more apparent. Even 
 more serious than the attacks of the Vulcanists, and 
 the disclosure of eruptive granites and porphyries 
 among the Transition rocks, were the discoveries 
 made among the fossiliferous stratified formations. 
 It was no longer possible to crowd and crush these 
 rocks within the narrow limits of the Wernerian 
 system, even in its most modified and improved 
 form. The necessity for expansion and for adopting 
 a perfectly natural nomenclature and classification, 
 based upon the actually observed facts, as these 
 were successively ascertained, made itself felt especially 
 in England and in France. Hence arose the curiously 
 mongrel terminology which is now in use. Certain 
 formations were named from some prominent mineral 
 in them, such as Carboniferous. Others were dis- 
 criminated by some conspicuous variety of rock, like 
 the Cretaceous series. Some took their names from 
 a characteristic structure, like Oolitic, others from 
 their relative position in the whole series, as in the 
 
40 8 Progress of Stratigraphy 
 
 case of Old Red Sandstone and New Red Sandstone. 
 Certain terms betrayed the country of their origin , 
 as did William Smith's English provincial names, 
 like Gault, Kellaways Rock, and Lias. 
 
 The growth of the present stratigraphical nomen- 
 clature is thus eminently characteristic of the early 
 rise and progress of the study of stratigraphy in 
 Europe. Precisians decry this inartificial and hap- 
 hazard language, and would like to introduce a 
 brand new harmonious and systematic terminology. 
 But the present arrangement has its historical interest 
 and value, and so long as it is convenient and intelli- 
 gible, I do not see that any advantage to science 
 would accrue from its abolition. The method of 
 naming formations or groups of strata after districts 
 where they are typically developed has long been in 
 use and has many advantages, but it has not sup- 
 planted all the original names, and I for my part 
 hope that it never will. 
 
 With regard to what are now known as the Tertiary 
 and Secondary formations, the Wernerian " Floetz," 
 under which they were all comprised, soon sank into 
 disuse. 1 But there was a long pause before the strata 
 of older date were subjected to the same diligent study. 
 
 1 One of the latest adaptations of the word was that of Keferstein 
 in his Tabellen fiber die vergleichende Geologic (1825). He frankly 
 threw over Wernerianism, but stuck to the pre- Wernerian Floetz, 
 which he arranged in five subdivisions, (i) Youngest Floetz, 
 alluvium, etc. ; (2) Tertiary Floetz, marls, gypsum, etc., of Paris, 
 Brown coal ; (3) Younger Floetz, or Chalk rocks, Chalk, Jura 
 Limestone, Greensand ; (4) Middle Floetz, or Muschelkalk Lias, 
 Keuper marl, Bunter sandstone, Zechstein ; (5) Old Floetz, or 
 Mountain Limestone Coal, Mountain Limestone. 
 
The IVernerian Lithological Seqtience 409 
 
 For this delay various good reasons may be assigned. 
 We have seen that William Smith's researches went 
 down into the Coal-measures, but he had only a 
 general and somewhat vague idea of the sequence of 
 the rocks beneath that formation. In the table 
 accompanying his map (1812) he placed below the 
 Coal the Derbyshire Limestone followed by Red and 
 Dunstone, Killas or Slate and lastly Granite, Syenite^ 
 and Gneiss. Some of these rocks were known to 
 be fossiliferous, but in general, throughout Western 
 Europe, they had been so disturbed and dislocated 
 that they no longer presented the proofs of their 
 sequence in the same orderly manner as had led to 
 the recognition of the succession of the younger 
 formations. 
 
 It will be remembered that in his original scheme of 
 classification Werner grouped some rocks as Primitive 
 (uranfangliche), and classed together as Floetz the 
 whole series of stratified formations between these and 
 the alluvial deposits. Further experience led him to 
 separate an intermediate group between the Primitive 
 and the Floetz, which he denominated Transition. He 
 considered that this group was " deposited during the 
 passage or transition of the earth from its chaotic to its 
 habitable state." 1 He recognised that it contains the 
 earliest organic remains, and believed it to include the 
 oldest mechanical deposits. He subdivided the Tran- 
 sition rocks rather by mineral characters than by 
 ascertained stratigraphical sequence. The hardened 
 variety of sandstone called greywacke formed by far 
 the most important member of the whole series, and 
 1 Jameson's Geognosy, p. 145 (1808). 
 
410 Transition and Greywacke 
 
 was believed by Werner to mark a new geognostic 
 period when, instead of chemical precipitates, mechanical 
 accumulations began to appear. 
 
 The two Wernerian terms Transition and Greywacke 
 survived for some years after the commencement of 
 the great stratigraphical impulse in the early years of 
 last century. They formed a kind of convenient limbo 
 or No-man's Land, into which any group of rocks 
 might be thrown which obstinately refused to reveal its 
 relations with the rest of the terrestrial crust. Down 
 to the base of the Carboniferous rocks, or even to the 
 bottom of the Old Red Sandstone, the chronological 
 succession of geological history seemed tolerably clear. 
 But beneath and beyond that limit, everything be- 
 tokened disorder. It appeared well-nigh hopeless to 
 expect that rocks so broken and indurated, generally 
 so poor in fossils, and usually so sharply cut off from 
 everything younger than themselves, would ever be 
 made to yield up a connected and consistent series of 
 chapters to the geological record. 
 
 And yet these chapters, if only they could be written, 
 would be found to possess the most vivid interest. 
 They would contain the chronicles of the earlier ages 
 of the earth's history, and might perhaps reveal to man 
 the geography of the first dry land, the sites of the 
 most ancient seas, the positions of the oldest volcanoes, 
 the forms of the first plants and animals that appeared 
 upon the planet. There was thus inducement enough 
 to attack the old rocks that contained within their 
 stony layers such precious memorials. 
 
 It is not that the Transition rocks were entirely 
 neglected. The keen interest awakened in fossils led 
 
Oldest Fossiliferous Rocks 411 
 
 to renewed search among the fossiliferous members of 
 that ancient series. A large number of organic remains 
 had been collected from Devonshire, Wales, the Lake 
 District, Rhineland, the Eifel, France, Sweden, Norway, 
 Russia, as well as from New York and Canada. These 
 fossils were distinct from those of the Secondary 
 formations, and they were obviously distributed, not 
 at random, but in groups which reappeared at widely 
 separated localities. 1 As yet, however, no clue had 
 been found to their stratigraphical sequence. Speci- 
 mens from what are now known as Cambrian, Silurian, 
 Devonian, and even Lower Carboniferous strata were 
 all thrown together as coming from the undefined 
 region of the Greywacke or Transition rocks. A task 
 worthy of the best energy of the most accomplished 
 geologist lay open to any man bold enough to under- 
 take to introduce among these rocks the same strati- 
 graphical method which had reduced the Secondary 
 and Tertiary formations to such admirable order, and 
 had furnished the means of comparing and correlating 
 these formations from one region to another. This 
 
 1 The amount and nature of the information in existence regarding 
 the Transition rocks or Greywacke, at the time when Murchison 
 entered upon their investigation, may be gathered from the summaries 
 contained in the contemporary general treatises on Geology. Even 
 as late as the spring of 1833, Lyell, after devoting about 300 pages 
 to the Tertiary formations, dismissed the Paleozoic series in twelve 
 lines (Principles of Geology, vol. iii. (1833), p. 326). One of the 
 fullest of the early descriptions of the older fossiliferous rocks, with 
 copious lists of fossils, will be found in the first edition of De la Beche's 
 Geological Manual (1831), p. 433, under the head of " Grauwacke 
 Group." But no attempt is there made to arrange the rocks strati- 
 graphically, and the fossil lists comprise organisms from all the older 
 Palaeozoic formations without discrimination of their horizons. 
 
412 Roderick Itnpey Murchison 
 
 task was at last accomplished by two men, working 
 independently of each other in Wales and the border 
 counties of England. Murchison and Sedgwick, whose 
 observations on ancient volcanic action have already 
 been referred to, carried the principles of Cuvier, 
 Brongniart, and William Smith into the chaos of old 
 Greywacke, and succeeded in adding the Devonian, 
 Silurian and Cambrian chapters to the geological record, 
 thus establishing a definite order among the oldest 
 fossiliferous formations, and completing thereby Palaeo- 
 zoic stratigraphy. 
 
 Roderick Impey Murchison, who was born in Ross- 
 shire in 1792, belonged to a family that had lived 
 for centuries among the wilds of the north-western 
 Highlands of Scotland, and had taken part in much 
 of the rough life of that remote and savage region. 1 
 Entering the army when he was only fifteen years of 
 age, he served for a time in the Peninsular war, and 
 carried the colours of his regiment at the battle of 
 Vimieira. During the subsequent retreat to Corunna 
 he narrowly escaped being taken prisoner by the 
 French. On the conclusion of the Napoleonic wars, 
 seeing no longer any prospect of military activity or 
 distinction, he quitted the army, married, and for some 
 years devoted himself with ardour to fox-hunting, in 
 which his love of an open-air life and of vigorous 
 exercise could have full gratification. But he was 
 made for a nobler kind of existence than that of a 
 mere Nimrod. His wife, a woman of cultivated 
 tastes, had led him to take much interest in art and 
 
 1 The biographical details are taken from my Life of Sir Roderick /. 
 Murchison, ^ vols. 8vo, 1875. 
 
His early Career 413 
 
 antiquities, and when Sir Humphry Davy, who also 
 recognised his qualities, urged him to turn his 
 attention to science, she strenuously encouraged him 
 to follow the advice. He at last sold his hunters, 
 came to London, and began to attend lectures on 
 chemistry and geology at the Royal Institution. 
 
 Murchison was thirty-two years old before he 
 showed any interest in science. But his ardent and 
 active temperament spurred him on. His enthusiasm 
 being thoroughly aroused, his progress became rapid. 
 He joined the Geological Society, and having gained 
 the goodwill of Buckland, went down to Oxford for his 
 first geological excursions under the guidance of that 
 genial professor. He then discovered what field- 
 geology meant, and learnt how the several parts of a 
 landscape depend for their position and form upon the 
 nature of the rocks underneath. He returned to 
 London with his zeal aflame, burning to put into 
 practice the principles of observation he had now been 
 taught. He began among the Cretaceous formations 
 around his father-in-law's home in Sussex, but soon 
 extended his explorations into Scotland, France and 
 the Alps, bringing back with him at the end of each 
 season a bundle of well-filled note-books from which 
 to prepare communications for the Geological Society. 
 These early papers, meritorious though they were, do 
 not call for any special notice here, since they marked 
 no new departure in geological research, nor added any 
 important province to the geological domain. 
 
 During six years of constant activity in the field, 
 Murchison, together with Sedgwick, worked out the 
 structure of parts of the west and north of Scotland, 
 
414 Murchison 
 
 and toiled hard in disentangling the complicated 
 structure of the eastern Alps ; he also rambled with 
 Lyell over the volcanic areas of Central and Southern 
 France. Thereafter he determined to try whether the 
 " interminable greywacke," as he called it, could not 
 be reduced to order and made to yield a stratigraphical 
 sequence, like that which had been so successfully 
 obtained among younger formations. At the time 
 when be began, that is, in the summer of 1831, 
 absolutely nothing was known of the succession of 
 rocks below the Old Red Sandstone. It was an 
 unknown land, a pathless desert, where no previous 
 traveller had been able to detect any trace of a practic- 
 able track towards order, or any clue to a system of 
 arrangement that would enable the older fossiliferous 
 rocks of one country to be paralleled, save in the 
 broadest and most general way, with those of another. 
 Starting with his "wife and maid, two good grey 
 nags and a little carriage, saddles being strapped behind 
 for occasional equestrian use/' Murchison made his 
 way into South Wales. In that region, as was well 
 known, the stratigraphical series could be followed 
 down into the Old Red Sandstone, and within the 
 frame or border of that formation, greywacke was 
 believed to extend over all the rest of the Principality. 
 Let me quote a few sentences in which Murchison 
 describes his first entry into the domain with which his 
 fame is now so inseparably linked. " Travelling from 
 Brecon to Builth by the Herefordshire road, the gorge 
 in which the Wye flows first developed what I had not 
 till then seen. Low terrace-shaped ridges of grey rock, 
 dipping slightly to the south-east, appeared on the 
 
His Silurian Quest 415 
 
 opposite bank of the Wye, and seemed to rise quite 
 conformably from beneath the Old Red Sandstone of 
 Herefordshire. Boating across the river at Cavansham 
 Ferry, I rushed up to these ridges, and, to my inex- 
 pressible joy, found them replete with Transition 
 fossils, afterwards identified with those at Ludlow. 
 Here then was a key, and if I could only follow this 
 out on the strike of the beds to the north-east, the case 
 would be good." l 
 
 With unerring instinct Murchison had realised that 
 if the story of old Greywacke was ever to be fully 
 told, a beginning must be made from some known and 
 recognisable horizon. It would have been well-nigh 
 useless to dive into the heart of the Transition hills, 
 and try to work out their complicated structure, for 
 even if a sequence could then have been determined, 
 there would have been no means of connecting it 
 with the already ascertained stratigraphical series, 
 unless it could be followed outwards to the Old 
 Red Sandstone. But by commencing at the known 
 base of that series, every fresh stage conquered was 
 at once a definite platform added to what had already 
 been established. 
 
 The explorer kept along the track of the rocks for 
 many miles to the north. No hunter could have 
 followed the scent of the fox better than he did the 
 outcrop of the fossiliferous strata, which he saw to come 
 out regularly from under the lowest members of the 
 Old Red Sandstone. Directed to the Wye by Buck- 
 land, he had the good-fortune to come at once upon 
 some of the few natural sections where the order 
 1 Life, vol. i. p. 182. 
 
4i 6 Murchison 
 
 of the higher Transition rocks of Britain, and their 
 relations to the overlying formations, can be distinctly 
 seen. He pursued the chase northwards until he 
 lost the old rocks under the Triassic plains of 
 Cheshire. " For a first survey," he writes, " I had 
 got the upper grauwacke, so called, into my hands, 
 for I had seen it in several situations far from each 
 other, all along the South Welsh frontier, and in 
 Shropshire and Herefordshire, rising out gradually 
 and conformably from beneath the lowest member 
 of the Old Red Sandstone. Moreover, I had ascer- 
 tained that its different beds were characterized by 
 peculiar fossils, ... a new step in British geology. 
 In summing up what I saw and realised in about 
 four months of travelling, I may say that it was 
 the most fruitful year of my life, for in it I laid 
 the foundation of my Silurian system. I was then 
 thirty-nine years old, and few could excel me in 
 bodily and mental activity." 1 
 
 Not only did the work of these four momentous 
 months mark a new step in British geology. It 
 began the lifting of the veil from the Transition 
 rocks of the whole globe. It was the first successful 
 foray into these hitherto intractable masses, and pre- 
 pared the way for all that has since been done in de- 
 ciphering the history of the most ancient fossiliferous 
 formations, alike in the Old World and in the New. 
 
 Contenting himself with a mere announcement of 
 
 his chief results at the first meeting of the British 
 
 Association, held in York in 1831, Murchison gave 
 
 a brief outline of his subdivisions of the Upper 
 
 1 Op. clt. pp. 183, 192. 
 
Establishes the Silurian system 417 
 
 Greywacke to the Geological Society in the spring 
 of I833. 1 He continued to toil hard in the field,, 
 mapping on the ground his various formations, and 
 making careful sections of their relations to each 
 other. Every fresh traverse confirmed the general 
 accuracy of his first observations, and supplied him 
 with further illustrations of the persistence and dis- 
 tinctness of the several groups into which he had 
 subdivided the Greywacke. At the beginning of 
 1834, he was able to present a revised and corrected 
 table of his stratigraphical results, each formation 
 being defined by its lithological characters and organic 
 remains, and the subdivisions being nearly what they 
 still remain. 2 The Ludlow rocks are shown to pass 
 upward into the base of the Old Red Sandstone, 
 and downward into the Wenlock group, which in 
 turn is succeeded below by the Horderley and May 
 Hill rocks, followed by the Builth and Llandeilo 
 flags. By the summer of 1835, at tne instigation 
 of Elie de Beaumont and other geological friends, he 
 had made up his mind as to the name that should 
 be given to this remarkable assemblage or system 
 of formations which he had disinterred from out of 
 the chaos of Greywacke. Following the good rule 
 that stratigraphical terms are most fitly formed on 
 a geographical basis with reference to the regions 
 wherein the rocks are most typically developed, he had 
 looked about for some appropriate and euphonious 
 term that would comprise his various formations 
 and connect them with that borderland of England 
 
 ^Proc. Geol. Soc. vol. i. (1833), p. 474. 
 'id. vol. ii. (1834), P- IJ - 
 
 2 D 
 
4i 8 Murchison 
 
 and Wales where they are so copiously displayed. 
 This territory was in Roman times inhabited by 
 the tribe of the Silures, and so he chose the term 
 Silurian a word that is now familiar to the geo- 
 logists of every country. 1 
 
 At the same time Murchison published a diagram- 
 matic section of his classification which, except in one 
 particular, has been entirely sustained by subsequent 
 investigation. He there groups the whole series of 
 formations as the Silurian system, which he divides 
 into Upper and Lower, drawing the line of separation 
 where it still remains. In the upper section come the 
 Ludlow and Wenlock rocks ; in the lower the Caradoc 
 and Llandeilo. The base of the series, however, is 
 made to rest unconformably on a series of ancient 
 slaty greywackes. No such base exists, for the Llandeilo 
 group passes downward into a vast series of older 
 sediments. At that time, however, both Murchison 
 and Sedgwick believed that a strongly marked separa- 
 tion lay between the Silurian System and the rocks 
 lying to the west of it. 
 
 Murchison used to maintain, with perfect justice, 
 that he had succeeded in his task, because he had 
 followed the method which had led William Smith 
 to arrange so admirably the Secondary formations of 
 England. He was able to show that, apart from mere 
 lithological differences, which might be of only local 
 value, his formations were definitely characterized, each 
 by its peculiar assemblage of organic remains. If 
 Smith's labours had not only brought the Mesozoic 
 rocks of England into order, but had furnished a 
 1 Phil. Mag. July 1835, p. 48. 
 
Prepares his Silurian Monograph 419 
 
 means of dealing in like fashion with the rocks of the 
 same age in other countries, there seemed no reason 
 why the palaeontological succession, found to distinguish 
 the greywacke in England and Wales, should not be 
 equally serviceable among the Transition rocks of 
 Europe and even of America. And if this result 
 should be achieved, Murchison might fairly claim that 
 he had added a series of new and earlier chapters to 
 the geological history of the globe. 
 
 The various brief communications to the Geological 
 Society, after the first discoveries in 1831, though 
 they had made geologists familiar with the main results 
 of Murchison's work, only increased their desire to 
 know the detailed observations on which his general- 
 isations were founded, and more particularly to have 
 complete information as to the assemblages of organic 
 remains which he had discovered. Previous collec- 
 tions from the Transition rocks were generally of little 
 service for stratigraphical purposes, because those of 
 widely separate horizons had all been mixed together. 
 But Murchison's specimens had been carefully gathered, 
 with the view of sustaining his classification, and for 
 the purpose of forming a basis of comparison between 
 the Transition rocks of Britain and those of other 
 countries. Early in the course of his wanderings along 
 the Welsh border, he had been urged to prepare a full 
 and more generally accessible account of his labours 
 than was offered in the publications of a learned Society. 
 Accordingly, adding this task to his other engagements, 
 he toiled at the making of a big book, until at last, 
 towards the end of the year 1838, that is, about seven 
 years from the time when he broke ground by the 
 
420 Murchison 
 
 banks of the Wye, he published his great work, The 
 Silurian System, a massive quarto of 800 pages, with 
 an atlas of plates of fossils and sections, and a large 
 coloured geological map. 
 
 The publication of this splendid monograph forms a 
 notable epoch in the history of modern geology, and 
 well entitles its author to be enrolled among the founders 
 of the science. For the first time, the succession of 
 fossiliferous formations below the Old Red Sandstone 
 was shown in detail. Their fossils were enumerated, 
 described and figured. It was now possible to carry 
 the vision across a vast series of ages, of which hitherto 
 no definite knowledge existed, to mark the succession 
 of their organisms, and thus to trace backward, far 
 farther than had ever before been possible, the history 
 of organised existence on this globe. 
 
 It has already been pointed (ante p. 268) that while 
 carefully working out the stratigraphy of the region, 
 Murchison had come upon various masses of eruptive 
 rock, some of which he recognised as intrusive, while 
 others he saw to be lavas and ashes that had been 
 ejected over the floor of the ancient ocean. In this 
 way he was able to present a picture of extraordinary 
 interest, in which the geologist could mark the position 
 of the old seas, trace the distribution of their organisms, 
 and note the sites of their volcanoes. 
 
 Even before the advent of his volume, the remark- 
 able results which he had succeeded in obtaining had 
 become widely known, and had incited other observers 
 all over the world to attack the forbidding domain of 
 Greywacke. In France, his classification had been 
 adopted, and applied to the elucidation of the older 
 
Adam Sedgwick 421 
 
 fossiliferous rocks by Elie de Beaumont and Dufr6noy, 
 who were then engaged in constructing their geo- 
 logical map of that country (p. 456). In Turkey it 
 had been similarly made available by Boue and De 
 Verneuil. Forchhammer had extended it to Scandi- 
 navia. Featherstonhaugh and Rogers had applied it 
 in the United States. Thus within a few years, the 
 Silurian system was found to be developed in all 
 parts of the world, and Murchison's work furnished 
 the key to its interpretation. 
 
 Let us now turn to the researches that were in 
 progress by another great master of English geology, 
 simultaneously with those of Murchison. Adam Sedg- 
 wick belonged to a family that had been settled for 300 
 years or more in the Dale of Dent, a picturesque 
 district which lies along the western border of York- 
 shire. To the end of his long and active life his heart 
 ever turned with fondness to the little valley where he 
 first saw the light, and to the kindly dalesmen among 
 whom he spent his boyhood. He remained to the end 
 a true dalesman himself, with all the frankness of 
 nature, mirthfulness and loyalty, so often found among 
 the natives of these pastoral uplands. He was born in 
 the year 1785, his father being the Vicar of Dent. 
 After receiving his school education at the neighbour- 
 ing little town of Sedbergh, he went to Trinity College, 
 Cambridge, which thenceforth became his home to the 
 end of his life. At the age of thirty-three he was 
 elected to the Woodwardian Professorship of Geology. 
 Up to that time, however, he had shown no special 
 interest in geological pursuits, and though he may have 
 read a little on the subject, his knowledge of it was 
 
422 Sedgwick 
 
 probably not greater than that of the average college 
 Fellow of his day. But his appointment as Professor 
 awakened his dormant scientific proclivities, and he at 
 once threw himself with all his energy and enthusiasm 
 into the duties of his new vocation. Gifted with 
 mental power of no common order, which had been 
 sedulously trained in a wide range of studies, possessing 
 a keen eye for the geological structure of a region, 
 together with abundant bodily prowess to sustain him 
 in the most arduous exertions in the field, eloquent, 
 witty, vivacious, he took at once the place of promin- 
 ence in the University which he retained to the last, 
 and he came with rapid strides to the front of all who 
 in that day cultivated the infant science of geology in 
 England. 
 
 What little geology Sedgwick knew, when he became 
 a professor of the science, seems to have been of a 
 decidedly Wernerian kind. He began his geological 
 writings with an account of the primitive ridge and its 
 associated rocks in Devon and Cornwall. His earliest 
 paper might have been appropriately printed in the 
 first volume of the Memoirs of the Wernerian Society. 
 In later years, referring to his Neptunist beginnings, he 
 confessed that " for a long while I was troubled with 
 water on the brain, but light and heat have completely 
 dissipated it," and he spoke of " the Wernerian non- 
 sense I learnt in my youth." 1 It was by his own 
 diligent work in the field that he came to a true 
 perception of geological principles. His excursions 
 carried him all over England, and enabled him to 
 
 l Life and Letters of Adam Sedgwick, by J. W. Clark and T. M'K. 
 Hughes, vol. i. p. 284. 
 
Conjoint labours with Murchison 423 
 
 bring back each season a quantity of specimens for his 
 museum, and a multitude of notes from which he 
 regaled the Cambridge Philosophical Society with an 
 account of his doings. Eventually he joined the 
 Geological Society of London, and found there a wider 
 field of action. After a time, Murchison also became 
 a fellow of that Society, and he and Sedgwick soon 
 formed a close intimacy. This friendship proved to be 
 of signal service to the cause of geological progress. 
 The two associates were drawn towards the same 
 departments of investigation. They began their co- 
 operation in the year 1827 by a journey through the 
 west and north of Scotland, and from that time onward 
 for many years they were constantly working together 
 in Britain and on the Continent of Europe. 
 
 It would be interesting, but out of place here, to 
 linger over the various conjoint labours of these two 
 great pioneers in Palaeozoic geology. We are only 
 concerned with what they did, separately and in con- 
 junction, towards the enlargement of the geological 
 record and the definite establishment of the Palaeozoic 
 systems. Sedgwick began his work among the older 
 fossiliferous formations by attacking the rugged and 
 complicated region of Cumberland and Westmoreland, 
 commonly known as the Lake District, and in a series 
 of papers communicated to the Geological Society he 
 worked out the general structure of that difficult 
 tract of country. Though fossils had been found 
 in the rocks, he did not at first make use of them 
 for purposes of stratigraphical classification. He ascer- 
 tained the succession of the great groups of strata 
 by noting their lithological characters. One of the 
 
424 Sedgwick and Murchison 
 
 most remarkable features of his investigation has been 
 above referred to (p. 266) the recognition of volcanic 
 rocks intercalated among the ancient marine sediments 
 of the Lake District. These rocks, since so fully 
 worked out, and now known as the " Borrowdale 
 Volcanic Series," of Lower Silurian age, were first 
 assigned to their true origin by Sedgwick, who thus 
 made an important contribution to the progress of 
 volcanic geology. 
 
 By a curious coincidence, Sedgwick and Murchison 
 both broke ground in Wales during the summer of 
 1831. But while Murchison determined to work his 
 way downward, from the known horizons of the Old 
 Red Sandstone of South Wales into the greywacke 
 below, Sedgwick, with characteristic dash, made straight 
 for the highest, ruggedest and most complicated tract 
 of North Wales. Returning to the same ground the 
 following year, he plunged into the intricacies of the 
 older Palaeozoic rocks, and succeeded in disentangling 
 their structure, tracing out their flexures and disloca- 
 tions, and ascertaining the general sequence of their 
 principal subdivisions. It was a splendid achievement, 
 which probably no other man in England at that time 
 could have accomplished. 
 
 But valuable as this work was, as a contribution to 
 the elucidation of the tectonic geology of a part of 
 Britain, it had not yet acquired importance in general 
 stratigraphy. In the first place, Sedgwick's groups 
 of strata were mere lithological aggregates. They 
 possessed as yet no distinctive characters that would 
 allow of their being adopted in the interpretation of 
 other countries, or even in distant parts of Britain. 
 
Their respective work in Wales 425 
 
 They contained fossils, but these had not been made 
 use of in defining the subdivisions. There was thus 
 neither a basis for comparison with other regions, nor 
 for the ascertainment of the true position of the North 
 Welsh rocks in the great territory of Greywacke. In 
 the second place, there was no clue to the connection of 
 these rocks with any known formation, for they were 
 separated from everything younger than themselves 
 by a strong unconformability. The Carboniferous and 
 Old Red Sandstone strata were found to lie on the 
 upturned edges of the older masses, and it was im- 
 possible to say how many intervening formations were 
 missing. 
 
 Murchison's researches, on the other hand, brought 
 to light the actual transition from the base of the Old 
 Red Sandstone into an older series of fossiliferous 
 formations underneath. There could, therefore, be no 
 doubt that part at least of his Silurian system was 
 younger than Sedgwick's series in North Wales. And 
 as he found what appeared to be older strata emerging 
 from underneath his system, and seeming to stretch 
 indefinitely into the heart of Wales, he naturally 
 believed these strata to be part of his friend's domain, 
 and at first left them alone. Such, too, was Sedgwick's 
 original impression. The two fellow-workers had not 
 drawn a definite boundary between their respective 
 territories, but they agreed that the Silurian series was 
 less ancient than the rocks of North Wales. 
 
 As a distinct name had been given to what they 
 believed to be the younger series, Murchison urged 
 his associate to choose an appropriate designation for 
 what they regarded as the older, and in the 4 summer 
 
426 Cambrian and Silurian Controversy 
 
 of 1835 the term " Cambrian " was selected. 1 By this 
 time Murchison had learnt that no hard and fast line 
 was to be drawn between the bottom of the Silurian 
 and the top of the Cambrian series. " In South Wales 
 he had traced many distinct passages from the lowest 
 member of the ' Silurian system ' into the underlying 
 slaty rocks now named by Professor Sedgwick the 
 Upper Cambrian." Sedgwick, on the other hand, 
 confessed that neither in the Lake District nor in 
 North Wales was the stratigraphical succession unbroken, 
 and that in these regions it was impossible to tell " how 
 many terms are wanting to complete the series to the 
 Old Red Sandstone and Carboniferous Limestone." : 
 He adopted a threefold subdivision into Lower, Middle, 
 and Upper Cambrian, but this classification rested 
 merely on mineral characters, no attempt having yet 
 been made by him to determine how far each of his 
 subdivisions was defined by distinctive fossils. 
 
 Eventually it was ascertained that the organic remains 
 in the upper part of the Cambrian system were the 
 same as those found in the Lower Silurian formations 
 as defined by Murchison. It became obvious that the 
 one series was really the equivalent of the other, and 
 that they ought not to be classed under separate names. 
 The officers of the Geological Survey, working from 
 the clearly defined Silurian formations, could draw no 
 line between these and those of North Wales, which 
 Sedgwick had classed as Cambrian. Finding the same 
 
 1 From " Cambria," the old name of Wales. Brit. Assoc. August 
 i835,P/5*7. Mag. vol. vii. (December 1835), P- 4 8 3 "On the Silurian 
 and Cambrian Systems" by A. Sedgwick and R. I. Murchison. 
 
 2 Op. at. 
 
Joachim Barrande 427 
 
 fossils in both, they felt themselves constrained to 
 class them all under the same designation of Silurian. 
 Murchison, of course, had no objection to the indefinite 
 extension of his system. Sedgwick, however, after 
 some delay, protested against what he considered 
 to be an unjustifiable appropriation of territory which 
 he had himself conquered. And thus arose a mis- 
 understanding between these two old comrades, which 
 deepened ere long into a permanent estrangement. 
 
 It is not my intention to enter here into the details 
 of this unhappy controversy. 1 My only object in 
 referring to it is to point out how far we are indebted 
 to Sedgwick for the establishment of the Cambrian 
 system. He eventually traced through a part of the 
 Welsh border a marked unconform ability between the 
 Upper Silurian formations and everything below them, 
 and he proposed that his Cambrian system should 
 be carried up to that physical break, and should thus 
 include Murchison's Lower Silurian formations. But 
 as these formations had been defined stratigraphically 
 and palaeontologically before he had been able to get 
 his fossils from North Wales examined, they obviously 
 had the right of priority. And the general verdict 
 of geologists went in favour of Murchison. 
 
 While this dispute was in progress in Britain, a 
 remarkable series of investigations by Joachim 
 Barrande (1799-1883) had made known the extra- 
 ordinary abundance and variety of Silurian fossils in 
 Bohemia. This distinguished observer not only re- 
 cognised the equivalents of Murchison's Upper and 
 
 1 1 have already given a full and, I believe, impartial account of it 
 in my Life of Murchison. 
 
428 The Primordial Fauna 
 
 Lower Silurian series, but found below that series a 
 still older group of strata, characterized by a different 
 assemblage of fossils, which he termed the first or 
 Primordial fauna. It was ascertained that represen- 
 tatives of this fauna occur in Wales among some of 
 the divisions of Sedgwick's Cambrian system, far below 
 the Llandeilo group which formed the original base 
 of the Silurian series. Eventually, therefore, since 
 the death of the two great disputants, there has been 
 a general consensus of opinion that the top of the 
 Cambrian system should be drawn at the upper limit 
 of the Primordial fauna. 1 
 
 By this arrangement, Sedgwick's name is retained for 
 an enormously thick and varied succession of strata 
 which possess the deepest interest, because they con- 
 tain the earliest records yet discovered of organised 
 existence on the surface of our globe. It was Sedg- 
 wick who first arranged the successive groups of strata 
 in North Wales, from the Bala and Arenig rocks 
 down into the depths of the Harlech anticline. His 
 classification, though it has undergone some slight 
 modification, remains to this day essentially as he left 
 it. And thus the name which he selected for his 
 system, and which has become one of the household 
 words in geological literature, remains with us a 
 memorial of one of the most fearless, strenuous, gentle 
 
 1 It has been proposed by Professor Lapworth that the strata named 
 by Murchison Lower Silurian and claimed by Sedgwick as Upper 
 Cambrian, should be taken from both and be given a new name, 
 " Ordovician." But this proposal is fair to neither disputant. By 
 all the laws that regulate scientific priority, the strata which were 
 first separated by Murchison and distinguished by their fossils, should 
 retain the name of Lower Silurian which he gave them. 
 
The ancient Greywacke 429 
 
 and lovable of all the master minds who have shaped 
 geological science into its present form. 
 
 By the establishment of the Cambrian and Silurian 
 systems a vast stride was made in the process of 
 reducing the chaos of Greywacke into settled order. 
 But there still remained a series of rocks in that chaos 
 which could not be claimed as either Cambrian or 
 Silurian, and did not yield fossils which would show 
 them to be Carboniferous. Before any dispute arose 
 between Sedgwick and Murchison as to the respective 
 limits of their domains in Wales, they were led to 
 undertake a conjoint investigation which resulted in 
 the creation of the Devonian system. The story of 
 the addition of this third chapter to early Palaeozoic 
 history may be briefly told. 
 
 It had long been known that Greywacke or Transi- 
 tion rocks cover most of the counties of Devon and 
 Cornwall. Closer examination of that region had shown 
 that a considerable tract of Greywacke, now known 
 as Culm-measures, contains abundant carbonaceous 
 material, and even yields fossil plants that were recog- 
 nised as identical with some of those in the Carboni- 
 ferous system. It was at first supposed by De la Beche 
 that these plant-bearing rocks lie below the rest of the 
 Greywacke of that part of the country. Murchison, 
 however, from the evidence of his clear sections in the 
 Silurian territory, felt convinced that there must be 
 some mistake in regard to the supposed position of 
 these rocks, for he had traversed all the Upper Grey- 
 wacke along the Welsh border, and had found it to 
 contain no land-plants at all, but to be full of marine 
 shells. He induced Sedgwick to join him in an 
 
43 Sedgwick and Murchison in Devonshire 
 
 expedition into Devonshire. The two associates, in 
 the course of the year 1836, completely succeeded in 
 proving that the Culm-measures, or Carboniferous 
 series, lay not below but above the rest of the Grey- 
 wacke of the south-west of England. But what was 
 that Greywacke, and what relation did it bear to the 
 rocks which had been reduced to system in Wales ? 
 
 The structure of the ground in the south-west of 
 England is by no means simple, and, indeed, is not 
 completely understood even now. The rocks have 
 been much folded, cleaved, crushed, and thrust over 
 each other. But besides these subsequent changes, 
 they present a great contrast in their lithological 
 characters to the Old Red Sandstone on the opposite 
 side of the Bristol Channel. Neither Sedgwick nor 
 Murchison could find any analogy between the Devon- 
 shire Greywacke and the red sandstones, conglomerates 
 and marls which expand into the Old Red Sandstone 
 of South Wales, and lie so clearly between the Car- 
 boniferous Limestone above and the Upper Silurian 
 formations below. Nor could Murchison see a re- 
 semblance between that Greywacke, or its fossils, 
 and any of his Silurian rocks. With their twisted 
 and indurated aspect, the Devonshire rocks looked so 
 much older than the gently inclined Silurian groups 
 by the banks of the Wye, that both he and Sedgwick 
 thought they more resembled the crumpled and broken 
 rocks of North Wales, and they accordingly first 
 placed them in the upper and middle parts of the 
 Cambrian system. 1 
 
 This correlation, however, was made mainly on 
 l Prof. Geol. Soc. ii. (1837), p. 560. 
 
William Lonsdale 431 
 
 lithological grounds. The Devonshire rocks were not 
 without fossils, and considerable collections of these 
 had already been gathered by different residents in 
 the county, but no one had yet endeavoured to 
 make a comparison between them and those of 
 known stratigraphical horizons elsewhere. This task 
 was undertaken at last by William Lonsdale (1794- 
 1871), who towards the end of the year 1837 came 
 to the conclusion that the greywacke and limestone 
 of South Devonshire, judged by their fossil contents, 
 must be intermediate between the Silurian and the 
 Carboniferous formations, that is, on the parallel of 
 the Old Red Sandstone of other parts of Britain. 
 
 Such a decision from a skilled palaeontologist raised 
 up some serious difficulties, which completely non- 
 plussed the two able geologists who the year before 
 had gone so gaily down to the south-west of Eng- 
 land to set matters right there. It seemed to them 
 as if Lonsdale's opinion was opposed to what had 
 been regarded as definitely settled in the stratigraphy 
 of the older stratified rocks. For two years they 
 continued in complete uncertainty as to the solution 
 of the problem. But at last after the examination of 
 innumerable specimens, endless discussion, and inter- 
 minable correspondence, they came to adopt Lonsdale's 
 views. They saw that the abundantly fossiliferous 
 rocks of South Devon contained, in their lower 
 members, fossils that reminded them of Silurian types, 
 while in their upper members, they yielded species 
 that were common also to the Carboniferous Lime- 
 stone. The two geologists therefore recognised in 
 these rocks an intermediate series of strata, containing 
 
43 2 Establishment of the Devonian System 
 
 a marine fauna which must have flourished between 
 the Silurian and the Carboniferous periods. That fauna 
 was not represented in the Old Red Sandstone, which, 
 with its traces of land-plants and remains of ganoid 
 fishes, appeared to have been accumulated under other 
 geographical conditions. To distinguish the series of 
 rocks containing this well-marked facies of marine 
 organisms, they chose the name " Devonian," from 
 the county where these rocks were originally studied 
 and where their true position was first ascertained. 1 
 The authors claimed that the establishment of the 
 Devonian system was " undoubtedly the greatest 
 change which has ever been attempted at one time 
 in the classification of British rocks.' 1 But it was far 
 more than that. It was the determination of a new 
 geological series of world-wide significance, the un- 
 folding of a new chapter in the geological annals of 
 our globe. Soon after Sedgwick and Murchison had 
 finally announced to the Geological Society their 
 reform of the geology of Devonshire, they started 
 for Rhineland, the Harz and Fichtelgebirge, and 
 succeeded in demonstrating that the Devonian system 
 is more extensively and completely developed there 
 than in its original Devonshire home. 
 
 I have dwelt on those labours of Sedgwick and 
 Murchison which more especially place their names 
 among those of the founders of geology. But besides 
 these exploits they each accomplished a vast amount 
 of admirable work, and helped thereby to widen the 
 bounds and strengthen the foundations of the science 
 to which they devoted their lives. To enter upon 
 
 1 Trans. Geol. Soc., 2nd ser. vol. v. pp. 688, 701 (April 1839). 
 
Personal characteristics of Mure his on 433 
 
 the consideration of these further achievements, how- 
 ever, would lead me beyond the limits to which this 
 volume must be restricted. 
 
 Murchison, who had succeeded De la Beche in 
 1855 as Director-General of the Geological Survey 
 of Great Britain, held that office until his death in 
 1871. To the last, he retained the erect military 
 bearing of his youth, and even under the weight of 
 threescore years and ten could walk a dozen of miles 
 and keep a keen eye on all the topographical and 
 geological features of the surrounding hills. Tali 
 and dignified in manner, with much of the formal 
 courtesy of an older time, he might seem to those 
 who only casually met him to be proud or even 
 haughty. But under this outer crust, which soon 
 dropped away in friendly intercourse, there lay a 
 friendly and helpful nature. Indomitable in his 
 power of work, restless in his eager energy in the 
 pursuit of his favourite science, full of sympathies 
 for realms of knowledge outside of his own domain, 
 wielding wide influence from his wealth and social 
 position, he did what no other man of his time 
 could do so well for the advance of science in 
 England. And his death at the ripe age of seventy- 
 nine left a blank in that country which has never 
 since been quite filled. 
 
 Sedgwick was in many respects a contrast to 
 Murchison. His powerful frame reminded one of 
 the race of dalesmen from which he sprang. His 
 eagle eyes seemed as if they must instantly pierce 
 into the very heart of the stifFest geological problem. 
 In his prime, he always made straight for the roughest 
 
 2 E 
 
434 Personal characteristics of Sedgwick 
 
 ground, the steepest slopes, or the highest summits, 
 and his bodily strength bore him bravely through 
 incredible exertion. Unfortunately his health, always 
 uncertain, would react on his spirits, and times of 
 depression and lethargy would come to interrupt 
 and retard his work, whether with hammer or pen. 
 But even his gloomiest fits he could turn into 
 merriment, and he would laugh at them and at him- 
 self, as he described his condition to some friend. 
 His gaiety of spirit made him the centre and life 
 of every company of which he formed part. His 
 frank manliness, his kindliness of heart, his trans- 
 parent childlike simplicity, his unwearied helpfulness 
 and his gentle tenderness, combined to form a char- 
 acter altogether apart. He was admired for his 
 intellectual grasp, his versatility, and his eloquence, 
 and he was beloved, almost worshipped, for the 
 overflowing goodness of his character. 
 
 When in the early part of this century, one 
 discovery after another was made which showed 
 that Werner's so-called primitive rocks reappeared 
 among his Transition and Floetz formations, a doubt 
 began to arise whether there were any primitive 
 rocks at all. 1 We have traced how Murchison and 
 Sedgwick cleared up the confusion of the Transition 
 series and created the Devonian, Silurian and Cam- 
 brian systems. In W T ales certain schists had been 
 detected by Sedgwick below his Cambrian rocks, 
 but they did not greatly interest him, and he never 
 
 1 Thus D'Aubuisson wrote in 1819 "Geology no longer possesses 
 a single rock essentially primitive" (Traite de Geognosie, tome ii. p. 
 J97)- 
 
William Edmond Logan 435 
 
 tried to make out their structure and history. After- 
 wards A. C. Ramsay (1814-1891) and his associates 
 claimed these schists as metamorphosed parts of the 
 Cambrian system. To this day their true position 
 has not been settled further than that they are known 
 to be pre-Cambrian. 
 
 The vast and varied series of rocks, which have 
 now been ascertained to underlie the oldest Cambrian 
 strata, have undergone much scrutiny during the last 
 half century, and their true nature and sequence are 
 beginning to be understood. The first memorable 
 onward step in this investigation was taken in 
 North America by William Edmond Logan (1798- 
 1875). Many years before his time, the existence 
 of ancient gneisses and schists had been recognised 
 both in the United States and in Canada. At the 
 very beginning of the century, the wide extent of 
 these rocks had been noted by W. Maclure, whose 
 general geological sketch-map of a large part of the 
 United States will be referred to on a later page. In 
 1824 and afterwards, Dr. J. J. Bigsby (1792-1881) 
 spent much time among these rocks to the north of 
 Lake Superior. Subsequently the gneisses of the 
 Adirondack Hills were described by Amos Eaton. 
 At the very beginning of his connection with the 
 Geological Survey of Canada in 1843, Logan con- 
 firmed the observation that the oldest fossiliferous 
 formations of North America lie unconformably on 
 a vast series of gneisses and other crystalline rocks > 
 to which he continued at first to apply the old term 
 Primary. By degrees, as he saw more evidence 
 of parallel structures in these masses, he thought 
 
436 Alexander Murray, S terry Hunt 
 
 that they were probably altered sediments, and he 
 referred to them as Metamorphic. That portion of 
 the series which includes thick bands of limestone 
 he proposed to consider as a separate and overlying 
 group. In the course of years, working with his 
 associates Alexander Murray and T. Sterry Hunt, he 
 was able to show the enormous extent of these 
 primary rocks, covering as they do several hundred 
 thousand square miles of the North American con- 
 tinent, and stretching northwards to the borders of 
 the Arctic Ocean. He proposed for these most 
 ancient mineral masses the general appellation of 
 Laurentian, from their development among the 
 Laurentide mountains. Afterwards he thought it 
 possible to subdivide them into three separate 
 groups, which he designated Upper, Middle and 
 Lower. In the course of his progress, he came 
 upon a series of hard slates and conglomerates, 
 containing pebbles and boulders of the gneiss, 
 and evidently of more recent origin, yet nowhere, 
 so far as he could see, separable by an undoubted 
 unconformability. These rocks, being extensively 
 displayed along the northern shores of Lake Huron, 
 he named Huronian. He afterwards described a 
 second series of copper-bearing rocks lying uncon- 
 formably on the Huronian rocks of Lake Superior. 
 He thus recognised the existence of at least three 
 vast systems older than the oldest fossiliferous for- 
 mations. He may be said to have inaugurated the 
 detailed study of Pre-Cambrian rocks. Subsequent 
 investigation has shown the structure of the regions 
 which he explored to be even more complicated and 
 
Logans services to Geology 437 
 
 difficult than he believed it to be, and various im- 
 portant modifications have been proposed in his work 
 and terminology by the able geologists of Canada 
 and the United States who have continued his 
 labours. But he will ever stand forward as one of 
 the pioneers of geology, who in the face of incredible 
 difficulties, first opened the way towards a compre- 
 hension of the oldest rocks of the crust of the 
 earth. 
 
CHAPTER XIV 
 
 
 
 PROGRESS of Stratigraphical Geology continued. Influence of Charles 
 Darwin. Adoption of Zonal Stratigraphy of fossiliferous rocks. 
 Rise of Glacial Geology, Louis Agassiz. Development of Geo- 
 logical map-making in Europe and North America. 
 
 THE fundamental principles of Stratigraphy having 
 been well established before the middle of last cen- 
 tury, this branch of geological science has during 
 the last fifty years undergone a remarkable expansion 
 from four influences. Firstly, it has been profoundly 
 modified by the writings of Darwin ; secondly, it 
 has been greatly affected by the introduction of 
 zonal classification among the fossiliferous formations ; 
 thirdly, it has been augmented by the rise and extra- 
 ordinary development of Glacial Geology ; and lastly, 
 it has enormously gained by the multiplication of 
 detailed geological maps. 
 
 I. Charles Darwin (1809-1882) contributed several 
 valuable works to the literature of geology. But it is 
 not for these that I now cite his name. The two 
 geological chapters in his Origin of Species produced 
 the greatest revolution in geological thought which has 
 occurred in my time. Younger students, who are 
 familiar with the ideas there promulgated, can hardly 
 realise the effect of them on an older generation. 
 
Influence of Darwin on Stratigraphy 439 
 
 They seem now so obvious and so well-established, 
 that it may be difficult to conceive a philosophical 
 science without them. 
 
 To most of the geologists of his day, Darwin's con- 
 tention for the imperfection of the geological record, 
 and his demonstration of it, came as a kind of surprise 
 and awakening. They had never realised that the 
 history revealed by the long succession of fossiliferous 
 formations, which they had imagined to be so full, was 
 in reality so fragmentary. And yet when Darwin 
 pointed out this fact to them, they were compelled, 
 sometimes rather reluctantly, to admit that he was 
 right. Some of them at once adopted the idea, as 
 Ramsay did, and carried it further into detail. 1 
 
 Until Darwin took up the question, the necessity 
 for vast periods of time, in order to explain the char- 
 acters of the geological record, was very inadequately 
 comprehended. Of course, in a general sense, the great 
 antiquity of the crust of the earth was everywhere 
 admitted. But no one before his day had perceived 
 how enormous must have been the periods required 
 for the deposition of even some thin continuous groups 
 of strata. He supplied a criterion by which, to some 
 degree, the relative duration of formations might per- 
 haps be apportioned. When he declared that the 
 intervals which elapsed between consecutive formations 
 may sometimes have been of far longer duration than 
 the formations themselves, contemporary geologists 
 could only smile incredulously in their bewilderment, 
 
 1 See the two Presidential Addresses to the Geological Society, 
 by A. C. Ramsay, Quart. Journ. Geol. Soc. vols. xix. (1863), xx. 
 (1864). 
 
44 Zonal Classification in Stratigraphy 
 
 but in a few years Ramsay showed by a detailed exam- 
 ination of the distribution of fossils in the sedimentary 
 strata that Darwin's suggestion must be accepted as an 
 axiom in geological theory. Again, the great naturalist 
 surmised that, before the deposition of the oldest known 
 fossiliferous strata, there may have been antecedent 
 periods, collectively far longer than from the date of 
 these strata up to the present day, and that, during 
 these vast, yet quite unknown, periods, the world may 
 have swarmed with living creatures. But his contem- 
 poraries could only shrug their shoulders anew, and 
 wonder at the extravagant notions of a biologist. But 
 who nowadays is unwilling to grant the possibility, nay 
 probability, of Darwin's surmise ? Who can look upon 
 the earliest Cambrian fauna without the strongest con- 
 viction that life must have existed on this earth for 
 countless ages before that comparatively well-developed 
 fauna came into existence ? For this expansion of 
 our geological vision, and for the flood of light 
 which has been thrown upon geological history by 
 the theory of evolution, we stand mainly indebted 
 to Charles Darwin. 
 
 II. Although the value of organic remains as a 
 means of identifying strata had been amply proved 
 during the earlier half of last century, neither geologists 
 nor palaeontologists were then aware of the extent 
 to which this chronological and stratigraphical test 
 could be carried out in the practical classification of 
 fossiliferous formations. They were content with the 
 broad subdivisions, often to a large extent based on 
 variations of sedimentary material, into which they 
 arranged the geological record. Eventually, however, 
 
Its application in Europe 441 
 
 it was shown by Oppel 1 and Quenstedt 2 that the 
 Jurassic series of Western Europe is not only capable 
 of subdivision into the lithological groups which 
 William Smith found to be distinguished by their 
 peculiar fossils, but that in these groups it was often 
 possible to trace a succession of horizons or zones, 
 each characterised by the presence of one or more 
 species of organic remains, which are either confined 
 to it or are more particularly conspicuous in it ; that 
 these zones can be followed over Germany, France 
 and England, and that, though the lithological character 
 of the strata may vary locally, the same sequence of 
 genera and species of fossils is on the whole maintained. 
 These observers found that the Ammonites are especi- 
 ally serviceable in the identification of such zones, on 
 account of their comparatively limited vertical range. 
 Thus in the Lias no fewer than seventeen zones have 
 been distinguished, each of which is known by the 
 name of its characteristic Ammonite, as the zone of 
 Psiloceras planorbe^ which lies at the bottom, and that 
 of Lytoceras jurense y which forms the top of the series. 
 The same principle of arrangement was afterwards 
 found to hold good for the Cretaceous formations, 
 and it has since been extended through the lower 
 Palaeozoic rocks down even to the bottom of the 
 Cambrian system. In the Silurian formations the 
 most useful fossils for zonal purposes have been 
 shown by Professor Lapworth to be the Graptolites. 
 The lowest known fossiliferous platform among the 
 rocks of the Old and New Worlds is that of the 
 
 l Die Juraformation Englands, Frankreichs und Deutschlands, 1856-58. 
 2 Der Jura, "1858. 
 
44 2 Rise of Glacial Geology 
 
 O!ene/!us-zone, where this distinctive genus of trilobite 
 is found. 
 
 This extension of William Smith's doctrine of 
 " Strata identified by fossils " has greatly contributed 
 to the progress of stratigraphy, and has furnished a 
 fresh clue to the interpretation of the structure of dis- 
 tricts in which the fossiliferous rocks have been much 
 dislocated and plicated. The general succession of 
 zones appears to be always similar, even in widely 
 separated regions ; but the same zones are not every- 
 where present nor do the same genera and species 
 always range over the world, though where they do 
 reappear they are believed to keep the same relative 
 order of occurrence. 
 
 III. The rapid development of Glacial Geology forms 
 one of the most interesting chapters in the history 
 of modern science. It began within the memory of 
 men yet living, and many of the observers who have 
 most energetically contributed to its progress are still 
 actively at work. The literature devoted to glaciation 
 has grown into a huge bulk, and continues to increase 
 every year. Looking back to the beginning of the 
 investigation we may note that although, as has been 
 already alluded to (p. 314), Playfair, at the beginning 
 of last century, had pointed out the pre-eminent place 
 of glaciers as the agents of transport for large blocks of 
 stone, his acute observation seems to have passed out 
 of mind. 1 Venetz and Charpentier were the first to 
 take up anew this interesting department of geology, 
 to trace the dispersal of the crystalline rocks of the 
 Central Alps outward across the great Swiss plain 
 ^Illustrations of the Huttonian Theory, p. 348. Ante p. 314. 
 
J. L. R. Agassiz, his early career 443 
 
 to the flanks of the Jura mountains, 1 and thus to 
 demonstrate the former great extension of the Swiss 
 glaciers. It was reserved, however, for Agassiz to 
 perceive the wide significance of the facts observed, 
 and to start the investigations that culminated in the 
 recognition of an Ice Age which involved the whole 
 of the northern part of our hemisphere, and in the 
 voluminous literature which has recorded the rapid 
 progress of this department of geology. 
 
 Jean Louis Rodolphe Agassiz (1807-1873) was born 
 in Switzerland, and rose to distinction by his scien- 
 tific work in Europe, but he went to the United 
 States when he was still only forty-two years of age, 
 and spent the last twenty-seven years of his life as 
 an energetic and successful leader of science in his 
 adopted home. His fame is thus both European 
 and American, and the geologists of New England, 
 not less than those of Switzerland, may claim him as 
 one of their most distinguished worthies. 
 
 We must pass over the brilliant researches into the 
 history of fossil fishes, which placed the name of 
 Agassiz high among the palaeontologists of Europe 
 when he was still a young man. What we are more 
 particularly concerned with here is the share he had 
 in founding the modern school of glacial geology. As 
 far back as the summer of 1836 he was induced to 
 visit the glaciers of the Diablerets and Chamounix, 
 and the great moraines of the Rhone valley, under 
 the guidance of Charpentier, whose views as to the 
 former extension of the ice he was disposed to doubt 
 
 l Schzveizer. Gesell. VerhandL 1834, p. 23 ; Ann. des Mines, viii. 
 (1835) P- 2I 9 5 Leonhard und Bronn, Ne-ues Jahrb. 1837, p. 472. 
 
444 Agassiz 
 
 and reject. But the result of this tour was to convince 
 him that the phenomena were even more stupendous 
 than Charpentier had asserted. In spite of the claims 
 of his palaeontological and zoological undertakings, 
 Agassiz was so fascinated by the ice-problem of the 
 Alps that he must needs pursue the subject with all 
 the enthusiasm and industry of his character. He 
 took the earliest opportunity of again investigating the 
 evidence furnished by the slopes of the Jura moun- 
 tains, and became so firmly convinced of the truth 
 and wide importance of the conclusions at which he 
 had arrived that he determined to publish these to the 
 world. Accordingly in the summer of the following 
 year (1837), when only thirty-three years of age, he 
 took the opportunity, as President of the Helvetian 
 Society of Natural Science, to give an address in which 
 he struck, with the hand of a master, the keynote of all 
 his future research in glaciation. Tracing the distribu- 
 tion of the erratic blocks above the present level of the 
 glaciers, and far beyond their existing limits, he con- 
 nected these transported masses with the polished and 
 striated rock-surfaces which were known to extend 
 even to the summits of the southern slopes of the 
 Jura. He showed, from the nature of these smooth 
 surfaces, that they could not have been worn into their 
 characteristic forms by any current of water. The fine 
 striae, engraven on them as with a diamond-point, he 
 proved to be precisely similar to those now being 
 scratched on the rocky floors of the modern glaciers, 
 and he inferred that the polished and striated rocks 
 of the Jura, even though now many leagues from 
 the nearest glacier, must have acquired their peculiar 
 
His glacial studies in Switzerland 445 
 
 surface from the action of ice moving over them, as 
 modern glaciers slide upon their beds. He was thus 
 led to conclude that the Alpine ice, now restricted to 
 the higher valleys, once extended into the central plain, 
 crossed it, and even mounted to the southern summits 
 of the Jura chain. 
 
 Before Agassiz took up the question, there were two 
 prevalent opinions regarding the transport of the 
 erratics. One of these called in the action of power- 
 ful floods of water, the other invoked the assistance 
 of floating ice. Agassiz combated these views with 
 great skill. His reasoning ought to have convinced 
 his contemporaries that his explanation was the true 
 one. But the conclusions at which he arrived seemed 
 to most men of the day extravagant and incredible. 
 Even a cautious thinker like Lyell saw less difficulty 
 in sinking the whole of Central Europe under the sea, 
 and covering the waters with floating icebergs, than in 
 conceiving that the Swiss glaciers were once large 
 enough to reach to the Jura. Men shut their eyes 
 to the meaning of the unquestionable fact that, while 
 there was absolutely no evidence for a marine sub- 
 mergence, the former track of the glaciers could be 
 followed mile after mile, by the rocks they had scored 
 and the blocks they had dropped, all the way from 
 their present ends to the far-distant crests of the 
 Jura. 
 
 Agassiz felt that the question was connected with 
 large problems in geology. The former vast extension 
 of the Swiss glaciers could be no mere accidental or 
 local phenomenon, but must have resulted from some 
 general lowering of temperature. He coupled with 
 
446 Agassiz 
 
 this deduction certain theoretical statements regarding- 
 former climates and faunas, which have not been sup- 
 ported by subsequent research. 
 
 The main conclusions which the Swiss naturalist 
 drew, so greatly interested him that he spent part of 
 five successive summers investigating the vestiges of 
 the old glaciers, and the operations of those of the 
 present time. He convinced himself that the great 
 extension of the ice was connected with the last great 
 geological changes on the surface of the globe, and with 
 the extinction of the large pachyderms, whose remains 
 are so abundant in Siberia. He believed that the 
 glaciers did not advance from the Alps into the plains, 
 but rather that ice once covered all the lower grounds, 
 and finally retreated into the mountains. 
 
 Having arrived at these conclusions from studies in 
 his native country, Agassiz was naturally desirous to 
 see how far his views could be tested or confirmed in 
 a region far removed from any existing glaciers. 
 Accordingly, in the year 1840, three years after his 
 address at Neufchatel, he had an opportunity of 
 visiting Britain, and took advantage of it to examine 
 a considerable part of Scotland, the north of England, 
 and the north, centre, west, and south-west of Ireland. 
 The results of this investigation were of remarkable 
 influence in the progress of glacial geology. Agassiz 
 demonstrated the identity of the phenomena in Britain 
 with those in Switzerland, and claimed " that not 
 only glaciers once existed in the British Islands, 
 but that large sheets (nappes) of ice covered all the 
 surface." l 
 
 1 Proc. Geol. Soc. vol. iii. (1840) p. 331. 
 
Impetus given by him to Glacial Research 447 
 
 These and the subsequent researches and glacial 
 monographs of the great Swiss naturalist started the 
 study of ancient glaciation. At first his conclusions 
 had been regarded as rank heresy by the older and 
 more conservative geologists of the day. Von Buch 
 " could hardly contain his indignation, mingled with 
 contempt, for what seemed to him the view of a youth- 
 ful and inexperienced observer." x A. von Humboldt 
 also threw cold water upon the ardour of his young 
 friend. But by degrees the opposition waned, and 
 Agassiz had the satisfaction of seeing his most 
 doughty opponents come over one by one to his 
 side. Nowhere were his triumphs more signal than 
 in the British Isles. Buckland (1784-1856), who 
 enjoyed the advantage of being shown the evidence 
 in Switzerland by Agassiz himself, was the first con- 
 vert of distinction. He signalised his change of 
 opinion by publishing a paper to prove the former 
 presence of glaciers in Scotland and the north of 
 England, followed by another communication on " the 
 glacio-diluvial phenomena in Snowdonia and the adja- 
 cent parts of North Wales." 2 Lyell about the same 
 time was won over by Buckland, and likewise hastened 
 to announce his acceptance of the new views by pub- 
 lishing a paper on the former existence of glaciers in 
 Forfarshire. 3 A few years later James David Forbes 
 (1808-1868) gave an account of glaciers that nestled 
 
 1 Louis Agassiz, his Life and Correspondence, by E. Gary Agassiz,. 
 vol. i. p. 264. 
 
 ' 2 Proc. Geol. Soc. vol. iii. (1841) pp. 332, 345, 579. 
 *Proc. Geol. Soc. vol. iii. (1841) p. 337. 
 
448 J* D. Forbes; C. Maclaren; R. Chambers 
 
 among the Cuillin Hills of Skye, 1 and Charles 
 Maclaren found glacier moraines in the valleys of 
 Argyleshire. 2 
 
 At first, however, the existence of former glaciers in 
 the valleys of Britain was the main conclusion sought 
 to be established. British geologists, and indeed geolo- 
 gists generally, were still for many years unwilling to 
 admit that not only the mountain-valleys, but even the 
 lowlands of the northern hemisphere were, at a late 
 geological period, buried under sheets of land-ice. 
 They preferred to call in the action of floating ice, 
 without perceiving that in so doing they involved 
 themselves in far more serious physical difficulties 
 than those which they sought to avoid. 
 
 Important service towards the ultimate acceptance 
 of Agassiz's enlarged conception of the glaciation of 
 Europe was rendered by Robert Chambers (1802- 
 1871), in a series of suggestive papers on the superficial 
 deposits and striated rocks of Scotland, 3 and in another 
 contribution (Tracings of the North of Europe > 1851), 
 
 l Edin. New Phil. Journ. xl. (1845) p. 76. To Forbes glacial 
 geology stands deeply indebted. He contributed to the Edinburgh 
 New Philosophical Journal an important series of letters from 1842 
 to 1851. He was likewise the author of excellent papers in 
 the Proceedings and Transactions of the Royal Society of Edinburgh, 
 of three memorable contributions on the viscous theory of glacier- 
 motion in the Philosophical Transactions of the Royal Society of 
 London (1846) and of two now classic works, his Travels through the 
 Alps of Savoy, etc. (1843) and Norway and its Glaciers (1853). 
 
 *Edin. New Phil. Journ. xl. (1845) P- I2 5 xlv "- ( l8 49) P- I0 ^ ; 
 xlix. (1850) p. 334 ; Ib. new series i. (1855) p. 189. 
 
 3 Edin. New Phil. Journ. liv. (1852) p. 229 ; Ibid, new ser. i. (1855) 
 p. 103 ; ii. p. 184. 
 
Earliest Geological Maps 449 
 
 in which he detailed the results of a journey made by 
 him to the north of Norway. In later years, by the 
 labours of T. F. Jamieson, A. C. Ramsay and others, 
 the extension of land-ice over the British Isles, and the 
 direction taken by the chief ice-sheets in their move- 
 ment across the country, came to be regarded as well- 
 established facts in Post-Tertiary geology. 
 
 The literature of this branch of the science is now 
 extensive and is increasing every year at a rapid rate. 
 In Europe and in North America the glaciation of 
 almost every region has been studied in great detail. 
 A vast quantity of important fact has been accumu- 
 lated to fill in the broad outlines traced by Agassiz, 
 but his teaching in all its essential parts has long 
 been generally accepted, and his name is now enshrined 
 as the main founder of glacial geology. 
 
 IV. Geological Maps. As the progress of strati- 
 graphical geology has been so largely aided by the 
 production of maps on which the distribution and 
 order of succession of the various rocks can be made 
 visible to the eye, it may not be inappropriate to 
 close a sketch of the foundation and development 
 of this branch of the science with a short account 
 of the first beginnings and early history of geological 
 cartography. It will be remembered that, as far back 
 as the year 1683, Martin Lister suggested that it 
 would be possible to show the distribution of the 
 soils, rocks and minerals of a country upon the 
 basis of an ordinary topographical map. He brought 
 before the Royal Society, and published in the Philo- 
 sophical Transactions, what was called " An ingenious 
 proposal for a new sort of Maps of Country, together 
 
 2 F 
 
450 Martin Lister s project 
 
 with tables of sands and clays, such chiefly as are 
 found in the north parts of England, drawn up about 
 ten years since, and delivered to the Royal Society, 
 March 12, 1683, by the Learned Martin Lister, 
 M.D." 1 In this " soile or mineral map" it was 
 proposed that " the soile might either be coloured 
 or otherwise distinguished by variety of lines or 
 etchings, but the great care must be, very exactly 
 to note upon the map where such and such soiles 
 are bounded. " By the term c soil ' Lister meant not 
 only the vegetable soil at the surface, but the sub- 
 soil and rocks underneath. "For I am of opinion," 
 he remarks, " such upper soiles, if natural, infallibly 
 produce such under minerals, and, for the most part, 
 in such order." <c If the limits of each soile appeared 
 upon a map, something more might be comprehended 
 from the whole and from every part, than I can 
 possibly foresee ; but I leave this to the industry 
 of future times." 
 
 Lister's proposal, however, does not seem to have 
 been followed by any practical result for some two 
 generations. In the year 1743, there was published in 
 England what is believed to be the earliest specimen 
 of a geological map, under the title of "A new Philo- 
 sophico-Chorographical Chart of East Kent, invented 
 and delineated by Christopher Packe, M.D." The 
 author sent a letter on the subject to the Royal 
 Society, and accompanied his Chart with a tract 
 wherein he states that his undertaking c ' is no dream 
 or devise, the offspring of a sportive imagination, 
 conceived and produced for want of something else 
 iL Trans, vol. xiv. p. 739. 
 
Christopher Packers map of Kent 45 1 
 
 to do, at my leisure in my study, but it is a real 
 scheme, taken upon the spot with patience and dili- 
 gence, by frequent or rather continual observations, 
 in the course of my journeys of business through 
 almost every the minutest parcel of the country : 
 digested at home with much consideration, and com- 
 posed with as much accuracy as the observer was 
 capable of." The Chart, which he indignantly refused 
 to call a map, is on the scale of rather more than an 
 inch and a half to a mile, and comprises the country 
 around Canterbury. It shows the positions of the 
 valleys and distinguishes the hills by the nature of 
 their component materials, such as chalk, " stone- 
 hills" (Lower Greensand) and " clay-hills," lying over 
 the plain of the Weald. As many parts of the valley 
 system are now dry, Packe inferred that they were 
 not hollowed by streams, but by the retiring waters 
 of the Deluge and have remained without change 
 
 ever since. 1 
 
 The mineralogical maps of Guettard have already 
 been noticed (p. no). The earliest of these was 
 presented to the Academy of Sciences of Paris in 
 1746, and the series was continued by the same 
 industrious observer until he handed over the further 
 prosecution of the task to his successor Mounet. 
 The early map of Fuchsel (1762) has been referred 
 to in Chapter VII. (p. 198). The first map in which 
 the various geological formations were represented by 
 washes of colour appears to have been one by G. 
 Glaser published at Leipzig in the year 1775 in his 
 Versuch einer mineralogischen Beschreibung der gefursteten 
 1 See a paper by Fitton in Phil. Mag. vol. i. (1832) p. 447. 
 
45 2 Eany maps in Germany and France 
 
 Graftschaft Henneberg, Chursachsischen Antheih. Three 
 years later a more important map, also in colour, was 
 issued at Leipzig in 1778 by J. F. W. Charpentier, 
 Professor in the Mining Academy of Freiberg, to 
 accompany his excellent quarto monograph on the 
 Mineralogische Geographic der Chursachsischen Lande. 
 Eight tints are used to discriminate granite, gneiss, 
 schist, limestone, gypsum, sandstone, river-sand, clay 
 and loam ; and there are also symbols to point out 
 the localities for basalt, serpentine, etc. 
 
 Palassou, in his Essai sur la MMralogie des Monts 
 Pyrenees, Paris, 1781, gave a series of maps with 
 engraved lines and signs, and also a route-map of 
 the part of France between Paris and the Mediter- 
 ranean, with the general mineralogical characters of 
 each line of route indicated by strips of colour. He 
 thus distinguished by a green line the granite rocks, 
 by a yellow line the u schists," and by a red line the 
 calcareous rocks. He also indicated the presence of 
 these various formations by different symbols, among 
 which was one for extinct volcanoes, that figures in the 
 Clermont region and also to the west of Montpellier. 
 
 William Smith's map, the history of which has 
 been referred to in Chapter XII. appeared in the year 
 .1815 with the following title "A Geological Map 
 of England and Wales, with Part of Scotland ; exhibit- 
 ing the Collieries, Mines, and Canals, the Marshes 
 and Fen Lands originally overflowed by the Sea ; 
 and the Varieties of Soil, according to the Variations 
 of the Substrata ; illustrated by the most descriptive 
 Names of Places, and of Local Districts ; showing 
 also the Rivers, Sites of Parks, and Principal Seats of 
 
Maps of Smith and Greenough 45 3 
 
 the Nobility and Gentry ; and the opposite coast of 
 France. By William Smith, Mineral Surveyor." The 
 map consists of fifteen sheets on the scale of five miles 
 to an inch ( 33 ^soo)? and measures 8 feet 9 inches in 
 height by 6 feet 2 inches in width. It was accompanied 
 with a quarto memoir or explanation of 50 pages. 
 
 While Smith's map was in preparation another large 
 geological map of England and Wales was indepen- 
 dently constructed by George Bellas Greenough (1778- 
 1855), an able geologist and a caustic critic of his 
 contemporaries and predecessors. 1 This map was 
 published in 1819. In the memoir which accompanied 
 it the author states that though he knew, as early 
 as 1804, that Smith had begun a similar work, he 
 had been led to believe that the design was abandoned. 
 Accordingly he undertook the task in 1808, and 
 having been encouraged by the Geological Society, of 
 which he was President, to complete it on the scale 
 of eleven miles to an inch ( 696 1 960 ) ? he proceeded 
 with it, and the map as prepared by him had been 
 more than a year in the hands of the engraver when 
 Smith's map appeared in 1815. Greenough's is a 
 better piece of engraving, and in some respects is 
 more detailed, especially as regards the formations 
 older than the Coal. It shows how much information 
 as to English stratigraphy had become available, partly 
 
 1 His qualities are characteristically exhibited in the volume which 
 he published in 1819 entitled A Critical Examination of the First 
 Principles of Geology. Every school of writers comes in there for its 
 share of his pungent criticism, and he shows his wide acquaintance 
 with the literature of the science. He was one of the founders 
 of the Geological Society, and as long as he lived was one of its 
 most respected and influential members. 
 
454 Macculloch" s Map of Scotland 
 
 no doubt through Smith's labours, before 1815. 
 Greenough's map was published and taken over by 
 the Geological Society, whose property it became. 
 The second edition, much revised and improved, was 
 published in 1839 and since then the map has from 
 time to time been brought up to date, and is still on 
 sale. But in its present form it differs much from 
 its author's original version. The appearance of this 
 map under the auspices of the Geological Society no 
 doubt affected the sale of Smith's, which does not 
 appear to have reached a second edition, though a 
 much reduced version of it was published in 1820. 
 
 In the list of the cartographical achievements of 
 the earlier decades of last century, a place must be 
 found for the remarkable maps and descriptions of 
 Scotland for which geology is indebted to the genius 
 and strenuous labour of John Macculloch. As already 
 stated (p. 261), his account of the structure of the 
 Western Isles, and the excellent maps and sections 
 which accompanied it, had a powerful influence in 
 promoting the progress of the study of igneous rocks, 
 and have long since taken their place as geological 
 classics. The same indefatigable observer, after years 
 of toil prepared a geological map of the whole 
 of Scotland, on the scale of four miles to an inch 
 ^.^i-^.) a most remarkable achievement to have 
 been accomplished unaided by one observer, at a 
 time when means of locomotion were as yet unde- 
 veloped over wide tracts of the country. 1 
 
 1 A Description of the Western Isles of Scotland, 1819 ; A Geological 
 Map of Scotland, 1840 ; and Memoirs to His Majesty's Treasury respect- 
 ing the Geological Map of Scotland, by J. Macculloch, 1836, 
 
Griffith's Map of Ireland 455 
 
 What Macculloch did for Scotland was done even 
 more efficiently for Ireland by Richard Griffith (1784- 
 1878), who, born in Dublin in 1784, devoted his long 
 and active life to carrying out surveys and other 
 investigations for the development of the resources of 
 his native country. In the course of his innumerable 
 journeys into all parts of the island, he accumulated a 
 large body of notes regarding its geology, and from 
 time to time inserted the data upon a map of Ireland. 
 This map was at last ordered by the Government to 
 be reconstructed and engraved on the scale of four 
 miles to an inch, and it was published in the spring of 
 1839. He continued to make improvements on it as 
 his knowledge of the geology of the country increased, 
 and to embody these in successive editions. If regard 
 be had to its large scale and to the amount of detail 
 expressed upon it, this work must be admitted to be 
 the most remarkable map of a whole country ever 
 constructed by a single individual. Its singular accuracy 
 and breadth of treatment have been amply proved by 
 the subsequent work of the Geological Survey. 
 
 Allusion has already been made to some of the 
 pioneer geological cartographers by whom the distribu- 
 tion of the rocks on the European continent was first 
 delineated. The early map of Germany by Von Buch 
 was noticed in Chapter VIII. (p. 251). In France the 
 mineralogical charts of Guettard and Palassou were 
 followed in 1 8 1 1 by the fuller geological map of the 
 Paris basin by Cuvier and Brongniart (p. 366), and in 
 1813 by that of Omalius d'Halloy (p. 377), embracing 
 a large tract of the north of France. The first general 
 geological map of the whole of France was prepared 
 
456 Institution of Geological Surveys 
 
 as a national undertaking. In the year 1820 a copy of 
 Greenough's map of England and Wales having been 
 sent to the Ecole des Mines at Paris, the desire arose 
 to provide France with a similar compendium of its 
 geology. Accordingly two engineers of the Mines 
 Department, Elie de Beaumont (1798-1874) and 
 Dufrenoy, were, in 1822, sent to England, where they 
 spent six months studying the principles on which the 
 English map had been constructed, and other subjects 
 connected with the project. The map of France, begun 
 in 1825 and completed in 1840, consisted of six sheets 
 on the scale of about eight miles to an inch. This great 
 work, so rapidly carried out, remains as a remarkable 
 monument of the genius of the two geologists under 
 whose supervision it was constructed. 
 
 The most important impulse towards the complete 
 and methodical investigation of the geology of wide 
 regions of the earth's surface has been given by the 
 institution of State surveys for the express purpose of 
 constructing geological maps of entire countries, com- 
 bined with the determination of the character and 
 distribution of useful minerals, and with the formation 
 of large collections of rocks, minerals and fossils. Great 
 Britain led the way in this line of national effort, by 
 inaugurating in 1835, at tne instigation and under the 
 personal supervision of Henry Thomas de la Beche, a 
 Geological Survey of the British Isles, together with 
 a School of Mines and a Mining Record Office. The 
 objects of the Geological Survey were to ascertain and 
 depict on maps, as accurately and in as much detail as 
 possible, on the scale of one inch to an English mile 
 (or 6 33eo)> the geological structure of the country, 
 
Geological Survey of Great Britain 457 
 
 together with the position and distribution of the 
 useful minerals; to prepare horizontal sections on a 
 scale of six inches to a mile ( 10 iUo)> showing the true 
 form of the surface and the ascertained or inferred 
 arrangement of the rocks underneath ; to publish 
 various memoirs and monographs in which the geology, 
 palaeontology, useful minerals and mineral industries 
 of the country should be fully described, and to form 
 a museum in which the rocks, minerals and fossils of 
 the British Isles should be amply represented by collec- 
 tions of specimens. The first maps issued by the 
 English Survey at once attracted notice as the largest 
 and most detailed maps that had yet appeared of any 
 part of the surface of the earth. De la Beche with 
 much sagacity and energy secured an able staff of 
 professors for his School of Mines, who did much 
 to stimulate the study of geology, mineralogy, palaeon- 
 tology, and natural history. Among these men were 
 Andrew C. Ramsay (1814-1891), Edward Forbes 
 (1815-1854), Warington Smyth (1817-1890), Lyon 
 Playfair (1818-1898), and John Percy (1817-1889). 
 De la Beche was succeeded in 1855 by Murchison, 
 under whom the staff of the Survey was much aug- 
 mented. The example set by the mother country has 
 been followed among the Colonies and Dependencies 
 of Britain, nearly all of which now have their inde- 
 pendent geological surveys. Most civilized countries 
 have also adopted similar organisations, so that now 
 detailed geological maps have been published for a 
 large part of Europe and North America. Even 
 Japan, in adopting the methods of the West, has not 
 omitted to include among them well-equipped geological 
 
45 8 Early American Surveys 
 
 and seismological surveys. By the detailed style of 
 mapping now in general use the geological structure 
 of the earth is becoming every year more accurately 
 known. International co-operation has likewise been 
 called into requisition. And we are now in possession 
 of a geological map of the greater part of the European 
 continent, prepared mainly by the collaboration of the 
 national surveys of the different countries, under the 
 auspices of the International Geological Congress. 
 
 While geology, as shown by the production of Maps 
 and Memoirs, has made such steady progress in the 
 Old World, its advance has been in many respects 
 even more rapid and striking in the New. When we 
 look back upon the history of the science on the other 
 side of the Atlantic the first name that prominently 
 comes before us is that of William Maclure (1763- 
 1 840), who has been called the " Father of American 
 Geology." He was born at Ayr in Scotland, and after 
 acquiring a fortune in business in London, he went 
 in 1796 to the United States and finally settled there. 
 Having developed a taste for geology in Europe, he 
 was soon attracted by the comparative simplicity and 
 the imposing scale of the geological structure of his 
 adopted country, and in the course of some years 
 made many journeys across the Eastern States. He 
 recorded on a map his observations of the distribution 
 of the rocks, and in 1809 made a communication on the 
 subject to the American Philosophical Society at Phila- 
 delphia. In 1817, having extended his knowledge 
 during the intervening eight years, he presented his 
 map to that Society, and it was then published. This 
 map is of special interest, as the first sketch of the 
 
Maclure, Eaton 459 
 
 geological structure of a large part of the United States. 
 It is on a small scale only 120 miles to an inch 
 (7603200) b ut it gi yes a broad delineation of the 
 general distribution of the larger formations. Maclure 
 was an open-minded adherent of the Freiberg system 
 of classification, for he frankly states that " although 
 subject to all the errors inseparable from systems 
 founded upon a speculative theory of origin, the 
 system of Werner is still the best and most compre- 
 hensive that has yet been formed." 
 
 The area depicted on this map extends from the 
 Canadian frontier to the Gulf of Mexico and from the 
 Atlantic Coast westward to about the 94th meridian. 
 The formations represented by colour are " Primitive 
 Rock, Transition Rock, Secondary Rock, Old Red 
 Sandstone, Alluvial Rock," and a green line is traced 
 from the north-east of New York State southwards 
 into Tennessee, " to the westward of which has been 
 found the greatest part of the salt and gypsum." 
 
 Among the errors of this sketch-map, hardly avoid- 
 able at the time, is the inclusion of various important 
 members of the Tertiary series among the alluvial 
 deposits. Further, among the Secondary formations 
 there is classed the horizontal westward extension of 
 the same rocks which, where highly inclined further 
 east, were regarded as Transition. But even with 
 these mistakes, the map must be admitted to be a 
 meritorious first outline of the geology of a vast 
 extent of territory. 
 
 In the year 1828 Amos Eaton (1776-1842) gave a 
 fuller synopsis than Maclure had done of the rocks of 
 North America, but misplaced some of the subdivisions. 
 
460 Early geological maps of United States 
 
 G. W. Featherstonhaugh (1780-1866), who was ap- 
 pointed " United States Geologist," was employed in 
 making various surveys for the Government, and 
 collected a large amount of material towards the 
 construction of a better geological map of the whole 
 country. Born in France and well acquainted with 
 the rocks of Europe, he was able to institute a closer 
 and more correct parallel between these rocks and 
 their American equivalents than had previously been 
 attempted. Another early pioneer in the geology of 
 the United States was Lardner Vanuxem (1792-1848) 
 whose work on the geological survey of the State of 
 New York deserves special recognition. As one of 
 his important services he corrected the error of taking 
 an inclined position as any reliable indication of the 
 relative age of rocks, and insisted on the paramount 
 importance of identifying strata by the organic remains 
 contained in them. Following this principle, he was 
 able to declare that the Transition rocks of Ohio, 
 Kentucky and Tennessee were shown by their fossils 
 to be of the same age as those at Trenton Falls in 
 New York, and all of them equivalents of some of the 
 Transition rocks of Europe wherein the same fossils 
 had been found. 
 
 Later than these early leaders came the group of 
 distinguished men who, by their researches and surveys 
 in Pennsylvania, not only added a series of admirable 
 maps to geological literature, but enriched the science 
 with suggestive memoirs on mountain structure 
 William Barton Rogers (1804-1882), Henry Darwin 
 Rogers (1808-1866), and J. P. Lesley (1819-1903). 
 Most of the other States of the American Union have 
 
Geological Surveys in United States 461 
 
 also instituted State Geological Surveys, and have pro- 
 duced excellent maps and descriptive memoirs, besides 
 amassing valuable collections of the minerals, rocks 
 and fossils of their respective domains. The central 
 government organised various surveys of the western 
 territories, which did admirable work of a pioneering 
 and prospective kind under such leaders as J. D. Powell 
 (1834-1902), J. S. Newberry (1822-1892), Clarence 
 King (1842-1898) and F. V. Hayden (1829-1887). 
 When it was found in 1879 tnat some of these explora- 
 tions were traversing the same ground, a consolidation 
 of the whole geological effort was made, and the Geo- 
 logical Survey of the United States was established. 
 The magnitude and excellence of the work already 
 accomplished by this organisation place it in the fore- 
 front of all national geological enterprises. 
 
CHAPTER XV 
 
 THE Rise of Petrographical Geology William Nicol, Henry 
 Clifton Sorby. Conclusion. 
 
 I TURN now to the Petrographical department of 
 geological inquiry, as exhibiting the last great forward 
 stride which the science has taken. We have seen 
 how greatly geology and mineralogy were indebted to 
 Werner for his careful and precise definitions. The 
 impulse which he gave to the study of Petrography 
 continued to show its effects long after his time, more 
 particularly in Germany. Methods of examination were 
 improved, chemical analysis was more resorted to, and 
 the rocks of the earth's crust, so far as related to their 
 ultimate chemical constitution, were fairly well known 
 and classified. Their internal structure, however, was 
 very imperfectly understood. Where they were coarsely 
 crystalline, their component minerals might be readily 
 determined ; but where they became fine-grained, little 
 more could be said about the nature and association 
 of their constituents than might be painfully deciphered 
 with the help of a hand-lens, or could be inferred from 
 the results of chemical analysis. Hence though not 
 actually at a standstill, petrography continued to make 
 but slow progress. In some countries indeed, notably 
 
IV. Nicolinvents a new petrological method 46 3 
 
 in Britain, it was almost entirely neglected in favour 
 of the superior attractions of fossils and stratigraphy. 
 But at last there came a time of awakening and rapid 
 advance. 
 
 In order to trace the history of this petrographical 
 resuscitation, we must in imagination transport our- 
 selves to the workshop of an ingenious and inventive 
 mechanician, William Nicol, who was a lecturer on 
 Natural Philosophy at Edinburgh in the early part of 
 last century. Among his inventions was the famous 
 prism of Iceland spar that bears his name. 1 Every 
 petrographer will acknowledge how indispensable this 
 little piece of apparatus is in his microscopic investi- 
 gations. He may not be aware, however, that it was 
 the same skilful hands that devised the process of 
 making thin slices of minerals and rocks, whereby 
 the microscopic examination of these substances has 
 become possible. 
 
 In the course of his experiments, Nicol hit upon 
 the plan of cutting sections of fossil wood, so as to 
 reveal its minutest vegetable structures. He took a 
 slice from the specimen to be studied, ground it 
 perfectly fiat, polished it, and cemented it by means 
 of Canada balsam to a piece of plate-glass. The 
 exposed surface of the slice was then ground down, 
 until the piece of stone was reduced to a thin pellicle 
 adhering to the glass, and the requisite degree of 
 transparency was obtained. Nicol himself prepared a 
 large number of slices of fossil and recent woods. 
 Many of these were described by Henry Witham in his 
 
 1 See Nicol's original account of his prism in Edln. New PhiL Journ. 
 vol. vi. (1829), p. 83. 
 
464 W. Nicol's services to Petrography 
 
 Observations on Fossil Vegetables (1831), to which Nicol 
 supplied the first published account of his process. 
 
 Here then geologists were provided with a method 
 of investigating the minutest structures of rocks and 
 minerals. As it was now made possible to subject 
 any part of the earth's crust to investigation with the 
 microscope, it might have been thought that those 
 who devoted themselves to the study of that crust, 
 especially those who were more particularly interested 
 in the structure, composition and history of rocks, 
 would have hastened to avail themselves of the new 
 facilities for research thus offered to them. 
 
 It must be confessed, I am afraid, that geologists are 
 about as difficult to move as their own erratic blocks. 
 They took no notice of the possibilities put in their 
 way by William Nicol. And so for a quarter of a 
 century the matter went to sleep. When Nicol 
 died, his instruments and preparations passed into the 
 hands of the late Mr. Alexander Bryson of Edinburgh 
 who, having considerable dexterity as a manipulator, 
 and being much interested in the process, made many 
 additions to the collections which he had acquired. 
 In particular, he made numerous thin slices of 
 minerals and rocks for the purpose of exhibiting the 
 cavities containing fluid, which had been described 
 long before by Brewster 1 and by William Nicol. 2 In 
 my boyhood I had frequent opportunities of seeing 
 these and the other specimens in Mr. Bryson's 
 cabinet, as well as the fine series of fossil woods 
 sliced so long before by Nicol. 
 
 1 Trans. Roy. Soc. Edin. vol. x. (1824), p. I. 
 
 2 Edin. New. Phil. Jour. vol. v. (1828), p. 94. 
 
H, C. Sorby 465 
 
 At last Mr. Henry Clifton Sorby came to Edin- 
 burgh, and had an opportunity of looking over the 
 Bryson collection. He was particularly struck with 
 the series of slices illustrating " fluid-cavities," and at 
 once saw that the subject was one of which the 
 further prosecution could not fail to " lead to 
 important conclusions in geological theory." 1 He 
 soon began to put the method of preparing thin 
 slices into practice, made sections of mica-schist, 2 
 and found so much that was new and important, 
 with a promise of such a further rich harvest of 
 results, that he threw his whole energy into the 
 investigation for several years, and produced at last 
 in 1858 the well-known memoir, On the Micro- 
 scopical Structure of Crystals^ which marks one of 
 the most prominent epochs of modern geology. I 
 have always felt a peculiar satisfaction in the re- 
 flection that though the work of William Nicol 
 was never adequately recognised in his lifetime, 
 nor for many years afterwards, it was his thin 
 slices, prepared by his own hands, that eventually 
 started Mr. Sorby on his successful and distinguished 
 career, and thus opened out a new and vast field for 
 petrographical investigation. 
 
 It is not necessary here to recapitulate the achieve- 
 ments which have placed Mr. Sorby's name at the 
 head of modern petrographers. He, for the first 
 time, showed how, by means of the microscope, it 
 was possible to discover the minute structure and 
 
 1 Quart. Journ. Geol. Soc. vol. xiv. (1858), p. 454. 
 
 2 Brit. Assoc. Reports, 1856, sections, p. 78. 
 
 3 Quart. Journ. Geol. Soc. vol. xiv. (1858), p. 453. 
 
 2 G 
 
466 H. C. Sorby 
 
 composition of rocks, and to learn much regarding 
 their mode of origin. He took us, as it were, 
 into the depths of a volcanic focus, and revealed 
 the manner in which lavas acquire their characters. 
 He carried us still deeper into the terrestrial crust, 
 and laid open the secrets of those profound abysses 
 in which granitic rocks have been prepared. His 
 methods were so simple, and his deductions so start- 
 ling, that they did not instantly carry conviction to 
 the minds of geologists, more particularly to those of 
 his own countrymen. The reproach that it was 
 impossible to look at a mountain through a micro- 
 scope was brought forward in opposition to the new 
 departure which he advocated. Well did he reply 
 by anticipation to this objection. " Some geologists, 
 only accustomed to examine large masses in the 
 field, may perhaps be disposed to question the 
 value of the facts I have described, and to think 
 the objects so minute as to be quite beneath their 
 notice, and that all attempts at accurate calculations 
 from such small data are quite inadmissible. What 
 other science, however, has prospered by adopting 
 such a creed ? What physiologist would think of 
 ignoring all the invaluable discoveries that have been 
 made in his science with the microscope, merely 
 because the objects are minute ? . . . With such 
 striking examples before us, shall we physical geo- 
 logists maintain that only rough and imperfect 
 methods of research are applicable to our own 
 science ? Against such an opinion I certainly must 
 protest ; and I argue that there is no necessary 
 connection between the size of an object and the 
 
Zirkel, Rosenbusch, Fouquk, Lkvy 467 
 
 value of a fact, and that, though the objects I 
 have described are minute, the conclusions to be 
 derived from the facts are great." 1 
 
 Professor Zirkel was the first geologist of note 
 who took up with zeal the method of investigation 
 so auspiciously inaugurated by Mr. Sorby. But some 
 five years had elapsed before he made his com- 
 munication on the subject to the Academy of Sciences 
 of Vienna. 2 From that date (1863) he devoted himself 
 with much zeal and success to the investigation, and 
 produced a series of papers and volumes which gave 
 a powerful impetus to the study of petrography. 
 This department of geology was indeed entirely re- 
 constituted. The most exact methods of optical 
 research were introduced into it by Professor Rosen- 
 busch. Professor Fouque, M. Michel Levy and others, 
 and the study of rocks once more competed with that 
 of fossils in attractiveness. We have only to look at 
 the voluminous literature which, within the last fifty 
 years has sprung up around the investigation of rocks, 
 to see how great a revolution has been effected by 
 the introduction of the microscope into the equipment 
 of the geologist. For this transformation we are, in 
 
 1 Quart. Journ. Geol. Soc. xiv. (1858), p. 497. See also Mr. 
 Sorby's Presidential Addresses to the Geological Society for 1879 
 and 1880. 
 
 2 Sitzungsber. Math. Naturzviss. vol. xlvii. ist part (1863), p. 226. 
 In this paper the author refers to previous occasional use of the micro- 
 scope for determining the mineralogical composition of rocks by Gustav 
 Rose, G. vom Rath, G. Jenzsch, M. Deiters and others. In England 
 the first geologist who published the results of his microscopical 
 examination of rocks was David Forbes, Popular Science Review (October 
 1867), vol. vi. p. 355. 
 
468 Varied avocations of Geologists 
 
 the first instance, indebted to William Nicol and 
 Henry Clifton Sorby. 
 
 In the account which has been presented in this 
 volume of the work of some of the more notable men 
 who have created the science of geology, one or two 
 leading facts stand out prominently before us. In the 
 first place, even in the list of selected names which 
 we have considered, it is remarkable how varied have 
 been the ordinary avocations of these pioneers. The 
 majority have been men engaged in other pursuits, 
 who have devoted their leisure to the cultivation of 
 geological studies. Steno, Guettard, Pallas, Fachsel, 
 and many more were physicians, either led by their 
 medical training to interest themselves in natural 
 history, or not seldom, even from boyhood, so fond 
 of natural history as to choose medicine as their 
 profession because of its affinities with that branch of 
 science. Giraud-Soulavie and Michell were clergymen. 
 Murchison was a retired soldier. Alexandre Brongniart 
 was at first engaged in superintending the porcelain 
 manufactory of Sevres. Desmarest was a hard-worked 
 civil servant who snatched his intervals for geology 
 from the toils of incessant official occupation. William 
 Smith found time for his researches in the midst of all 
 the cares and anxieties of his profession as an engineer 
 and surveyor. Hutton, Hall, De Saussure, Von Buch, 
 Lyell and Darwin were men of means, who scorned 
 a life of slothful ease, and dedicated themselves and 
 their fortune to the study of the history of the earth. 
 Playfair and Cuvier were both teachers of other 
 branches of science, irresistibly drawn into the sphere 
 
Slow growth of some parts of Geology 469 
 
 of geological inquiry and speculation. Of the whole 
 gallery of worthies that have passed before us, a 
 comparatively small proportion could be classed as in 
 the strictest sense professional geologists, such as 
 Werner, Sedgwick and Logan. Were we to step 
 outside of that gallery, and include the names of all 
 who have helped to lay the foundations of the science 
 we should find the proportion to be still less. 
 
 From the beginning of its career, geology has owed 
 its foundation and its advance to no select and privi- 
 leged class. It has been open to all who cared to 
 undergo the trials which its successful prosecution 
 demands. And what it has been in the past, it re- 
 mains to-day. No branch of natural knowledge lies 
 more invitingly open to every student who, loving the 
 fresh face of Nature, is willing to train his faculty of 
 observation in the field, and to discipline his mind by 
 the patient correlation of facts and the fearless dissec- 
 tion of theories. To such an inquirer no limit can be 
 set. He may be enabled to rebuild parts of the temple 
 of science, or to add new towers and pinnacles to its 
 superstructure. But even if he should never venture 
 into such ambitious undertakings, he will gain, in the 
 cultivation of geological pursuits, a solace and enjoy- 
 ment amid the cares of life, which will become to him 
 a source of the purest joy. 
 
 In the second place, the history of geological science 
 presents some conspicuous examples of the length of 
 time that may elapse before a fecund idea comes to 
 germinate and bear fruit. Consider for a moment 
 how many years passed before the stratigraphical con- 
 ceptions of Fttchsel, Lehmann, and Giraud-Soulavie 
 
47 Tardy reception of new doctrines 
 
 took more definite shape in the detailed investigations 
 of Cuvier, Brongniart and Smith, and how many more 
 years were needed before the Secondary and Tertiary 
 formations were definitely arranged and subdivided as 
 they now stand in our tables. Remember too that 
 even after the principles of stratigraphy had been settled, 
 a quarter of a century had slipped away before they 
 were successfully applied to the Transition rocks, and 
 a still longer time before the system of zonal classifi- 
 cation was elaborated. Note how long the controversy 
 lasted over the origin of basalt, and how slowly 
 came the recognition of volcanic action as a normal 
 part of terrestrial energy, which has been in operation 
 from the earliest geological times and has left its 
 memorials even in the oldest known parts of the crust 
 of the earth. Mark also, in the history of physio- 
 graphical geology, that though the principles of this 
 branch of science were in large measure grasped by 
 Desmarest, De Saussure and Hutton in the eighteenth 
 century, their work was neglected and forgotten until 
 the whole subject has been revived and marvellously 
 extended in our own day. Again, let me recall how 
 slowly the key that now unlocks the innermost mysteries 
 of rock-structure was made use of. Five-and-twenty 
 years elapsed after William Nicol had shown how 
 stony substances could be investigated by means of the 
 microscope, before Mr. Sorby called the attention of 
 geologists to the enormous value of the method thus 
 put into their hands. Other five years had to pass 
 before the method began to be taken up in Germany, 
 and a still longer time before it came into general use 
 all over the world. 
 
Tendency to specialisation 471 
 
 Such instances as these lead to two reflections. On 
 the one hand, they assure us of the permanent vitality 
 of truth. The seed may be long in showing signs of 
 life, but these signs come at last. On the other hand, 
 we are warned to be on the outlook for unrecognised 
 meanings and applications in the work of our own day 
 and in that of older date. We are taught the necessity 
 not only of keeping ourselves abreast of the progress 
 of science at the present time, but also of making our- 
 selves acquainted as far as we possibly can with the 
 labours of our predecessors. It is not enough to toil 
 in our little corner of the field. We must keep our- 
 selves in touch both with what is going on now, and 
 with what has been done during the past in that and 
 surrounding parts of the domain of science. Many a 
 time we may find that the results obtained by some 
 fellow-labourer, though they may have had but little 
 significance for him, flash a flood of light on what 
 we have been doing ourselves. 
 
 I am only too painfully aware how increasingly 
 difficult it is to find time for a careful study of the 
 work of our predecessors, and also to keep pace with 
 the ever-rising tide of modern geological literature. 
 The science itself has so widened, and the avenues 
 to publication have so prodigiously multiplied, that 
 one is almost driven in despair to become a specialist, 
 and confine one's reading to that portion of the litera- 
 ture which deals with one's own more particular branch 
 of the science. But this narrowing of the range of our 
 interests and acquirement has a markedly prejudicial 
 effect on the character of our work. There is but 
 slender consolation to be derived from the conviction, 
 
472 Avoidance of Dogmatism 
 
 borne in upon us by ample and painful experience, that 
 in the case of geological literature, a large mass of the 
 writing of the present time is of little or no value for 
 any of the higher purposes of the science, and that it 
 may quite safely and profitably, both as regards time 
 and temper, be left unread. If geologists, and especi- 
 ally young geologists, could only be brought to realise 
 that the addition of another paper to the swollen flood 
 of our scientific literature involves a serious responsi- 
 bility ; that no man should publish what is not of real 
 consequence, and that his statements when published 
 should be as clear and condensed as he can make them, 
 what a blessed change would come over the faces of 
 their readers, and how greatly would they conduce 
 to the real advance of the science which they wish to 
 serve ! 
 
 In the third and last place, it seems to me that one 
 important lesson to be learnt from a review of the 
 successive stages in the foundation and development 
 of geology is the absolute necessity of avoiding dog- 
 matism. Let us remember how often geological theory 
 has altered. The Catastrophists had it all their own 
 way until the Uniformitarians got the upper hand, only 
 to be in turn displaced by the Evolutionists. The 
 Wernerians were as certain of the origin and sequence 
 of rocks as if they had been present at the formation 
 of the earth's crust. Yet in a few years their notions 
 and overweening confidence became a laughing-stock. 
 From the very nature of its subject, as I have already 
 remarked, geology does not generally admit of the 
 mathematical demonstration of its conclusions. They 
 rest upon a balance of probabilities. But this balance 
 
Conclusion 473 
 
 is liable to alteration, as facts accumulate or are better 
 understood. Hence what seems to be a well-established 
 deduction in one age may be seen to be more or 
 less erroneous in the next. Every year, however, 
 the data on which these inferences are based are more 
 thoroughly comprehended and more rigidly tested. 
 Geology now possesses a large and ever-growing 
 body of well-ascertained fact, which will be destroyed 
 by no discovery of the future, though it will doubt- 
 less be vastly augmented, while new light may be cast 
 on many parts of it now supposed to be thoroughly 
 known. 
 
 Each of us has it in his power to add to this 
 accumulation of knowledge. Careful and accurate 
 observation is always welcome, and may eventually 
 prove of signal importance. While availing ourselves 
 freely of the use of hypothesis as an aid in ascertaining 
 the connection and significance of facts, we must be 
 ever on our guard against premature speculation and 
 theory, clearly distinguishing between what is fact and 
 what may be our own gloss or interpretation of it. 
 Above all, let us preserve the modesty of the true 
 student, face to face with the mysteries of Nature 
 Proving all things and holding fast that which we 
 believe to be true, let us look back with gratitude 
 and pride to what has been achieved by our forerunners 
 in the race, and while we labour to emulate their 
 devotion, let us hold high the torch of science, and 
 pass it on bright and burning to those who shall 
 receive it from our hands. 
 
INDEX. 
 
 Achelous, River, n, 35. 
 Aeolian Isles, 15, 20. 
 Agassiz, J. L. R., 443. 
 Agricola, 146, 147, 221. 
 "Alluvial Rocks" of Werner, 
 
 215. 
 Alps, glaciers of, in the history of 
 
 Glacial Geology, 443, 444. 
 America, progress of geology in 
 
 North, 458. 
 Ammonites, value of, in zonal 
 
 stratigraphy, 441. 
 Anaxagoras on earthquakes, 13. 
 Anaximenes on earthquakes, 13, 
 
 23- 
 
 Ancients, growth of naturalistic 
 views among, 7, 40 ; geological 
 conceptions of, 13, 28, 33 ; 
 liberty of speculation among, 
 40. 
 
 Animals and plants, Lamarck on 
 geological action of, 360. 
 
 Arabs, science among the, during 
 the Dark Ages, 42. 
 
 Archiac, Comte d', 108, 115, 
 181. 
 
 Arduino, G., 180, 195. 
 
 Aristotle on cosmical position of 
 the earth, 1 2 ; on earthquakes, 
 14 ; connected earthquakes 
 with volcanoes, 15 ; on origin 
 of minerals, 1 6 ; on rivers, 
 28 ; on former changes of 
 earth's surface, 34 ; on a 
 Universal Flood, 52. 
 
 Auvergne, volcanic geology of, 
 127-135, 141, 150, 158, 243, 
 246, 247 ; first topographical 
 map of, 154, 1 60, 169. 
 
 Avicenna on geological changes, 
 43- 
 
 Banks, Sir Joseph, 148, 391. 
 
 Barrande, J., 427. 
 
 Barrois, C., 271. 
 
 Basalt, controversy as to the origin 
 of, 135, 146, 149, 152, 1 60, 
 202, 221, 223, 242, 244,246, 
 327 ; supposed fossils in, 328. 
 
 Beringer, J. B., 102. 
 
 Bi g sb 7> J- JU435- 
 
 Black, Dr. Joseph, 285, 288, 316. 
 
 Black Sea, gain of land on shores 
 of, 29. 
 
 Blode, K. A., 263. 
 
 Boate's Ireland's Natural! His- 
 toric, 113. 
 
 Bohemia, Silurian fauna of, 427. 
 
 Bosphorus, gain of land in, 29. 
 
 Bottiger, C. A., 207. 
 
 Boue, Ami, 241, 247, 263, 421. 
 
 Boule, M., 271. 
 
 Breislak, S., 256, 402. 
 
 Brewster, D., 464. 
 
 Britain, Agassiz finds traces of 
 old glaciers in, 446 ; Buckland, 
 Lyell, and J. D. Forbes on 
 glaciers in, 447. 
 
 British Association for the Ad- 
 vancement of Science, 416. 
 
Index 
 
 475 
 
 Brocchi, G., 51. 
 
 Brongniart, Alexandra, 365. 
 
 Bryson, A., 464. 
 
 Buckland, W., 413, 415, 447. 
 
 Buch, L. von, 242 ; lineage and 
 education, 245 ; his first geo- 
 logical work, 246 ; visits 
 Auvergne and abandons Wer- 
 nerian doctrine of the aqueous 
 origin of basalt, 246 ; his 
 account of Auvergne, 247 ; his 
 investigations in Scandinavia, 
 250 ; on recent uprise of 
 Scandinavia, 251 ; his geo- 
 logical map of Germany, 251 ; 
 his extensive travels, 252 ; his 
 personal appearance and habits, 
 253 ; opposes glacial geology, 
 
 447- 
 
 Buffalo, fossil, of Siberia, 179. 
 
 Buffon, G. L. Leclerc de, 88 ; 
 his Theory of the Earth, 89 ; 
 his Epoques de la Nature, 90, 
 140, 193 ; on "days" of 
 Creation, 91 ; on earliest 
 mountains and valleys, 92, 94 ; 
 on first beginnings of life, 92 ; 
 on origin of volcanoes, 93 ; on 
 age of the earth, 95, 96 ; on 
 denudation, 94, 95 ; on 'final 
 extinction of the earth by cold, 
 95 ; his literary skill, 96. 
 
 Burnet, Thomas, his Sacred Theory, 
 66, 90. 
 
 Cambrian system, established by 
 Sedgwick, 426 ; zonal strati- 
 graphy applied to, 441. 
 
 Cardano on fossil shells, 51. 
 
 Cartography, history of geological, 
 
 ^ 77> I"; "5- 
 
 Cataclysmists or Catastrophists, 
 
 .: 374.472- 
 
 Catherine II., Empress of Russia, 
 
 ,'7 6 : 
 
 Cesalpino on fossils, 53. 
 
 Chalk, fusion experiments on, 
 324 ; Cuvier and Brongniart 
 on the, 368 ; zonal stratigraphy 
 applied to, 441. 
 
 Chambers, R., 448. 
 
 Charpentier, T. von, 442, 443. 
 
 Charpentier, J. F. W., 452. 
 
 Childrey's Britannia Baconica, 113. 
 
 Chronology, geological, deter- 
 mined by fossils, 336. 
 
 Church, influence of the, on 
 geological speculation, 44, 64, 
 
 65> 73, 97- 
 
 Clerk, John, of Eldin, 285, 288, 
 316. 
 
 Condorcet on Guettard, 105, 
 107, 109, 137. 
 
 Conybeare and Phillips' Geology 
 of England, 108, 265, 399, 402. 
 
 Cook, voyages of Captain, 172,176. 
 
 Cosmogonies, origin of popular, 
 6, 65. 
 
 Cosmogonists, rise of the English 
 65 ; French Descartes, 79 ; 
 Leibnitz, 81 ; De Maillet, 84; 
 Buffon, 88. 
 
 Coupe, 344. 
 
 Cretaceous system, zonal strati- 
 graphy applied to, 441. 
 
 "Crystallite"ofSirJames Hall, 3 20. 
 
 Cunningham, R. Hay, 331. 
 
 Cuvier, on Scheuchzer's supposed 
 fossil man, I oo ; on Guettard, 
 107 ; on Desmarest, 142, 143, 
 145, 171 ; on De Saussure, 
 183, 308 ; on Werner, 207, 
 2 34 2 35> 2 37 ; on granite, 
 308 ; birth and early career 
 of, 363 ; becomes Professor of 
 Comparative Anatomy, 364 ; 
 on extinct vertebrates, 364 ; 
 his services to geology, 372, 
 401 ; his doctrine of catas- 
 trophes, 3/3 ; becomes Per- 
 petual Secretary of the Institute 
 of France, 376. 
 
47 6 
 
 Index 
 
 D'Alembert and Desmarest, 143. 
 
 Danube, River, n, 32. 
 
 Darwin, C., influence of, on 
 modern geology, 438. 
 
 Daubeny, C., 109, 264. 
 
 Daubree, A., 325. 
 
 D'Aubuisson, J. F., 218, 231, 
 241, 391, 402, 434. 
 
 Davy, Sir Humphry, 413. 
 
 De la Beche, H. T., 265, 402, 
 411, 429, 456. 
 
 De Luc, J. A., 1 86, 296, 330. 
 
 De Verneuil, 6. P., 421. 
 
 Deiters, M., 467. 
 
 Deltas, Strabo on, 30. 
 
 Deluge of Noah, invoked to 
 account for fossil organic re- 
 mains, 46, 48, 51, 60, 61, 67, 
 98, 100, 102 ; local and 
 transitory nature of, recog- 
 nised, 52, 61, 71 ; invoked as 
 one of the great geological 
 events in the history of the 
 earth, 66, 67, 90. 
 
 Democritus on earthquakes, 13. 
 
 Denudation, Steno on, 57 ; Ray 
 on, 74, 126; Buffon on, 94, 
 95 ; Guettard on, 121, 139; 
 Desmarest on, 158, 161 ; De 
 Saussure on, 188 ; Hutton on, 
 311. 
 
 Descartes, R., cosmogony of, 79. 
 
 Deshayes, 404. 
 
 Desmarest, N., on Guettard, 107, 
 129, 132, 134; biographical 
 sketch of, 141 ; earliest geo- 
 logical essay of, 143 ; begins 
 the study of Basalt and the 
 volcanic region of Auvergne, 
 147 ; discovers the volcanic 
 origin of Basalt, 152, 223 ; 
 his demonstration of volcanic 
 history and denudation in 
 Auvergne, 160 ; his caution in 
 the publication of his obser- 
 vations, 153, 154, 155, 161 ; 
 
 his avoidance of controversy,. 
 162, 167, 169, 175 ; on 
 Physical Geography, 168 ; 
 sketch of, by Cuvier, 171 ; not 
 cited by L. von Buch, 247 ; 
 on Hutton, 295 ; his account 
 of geological progress in the 
 Paris Basin, 342, 343, 344. 
 
 Deucalion, flood of, 35 [mis- 
 printed " Decalion " in text]. 
 
 Deville, Ch. Sainte-Claire, 108. 
 
 Devonian system, established by 
 Sedgwick and Murchison, 429. 
 
 Diderot and D'Alembert, En- 
 cyclopedic Methodlque of, 107, 
 168, 169. 
 
 Diluvialists, rise of the, 47. 
 
 Dolomieu, G. de, 174, 254, 260, 
 321. 
 
 Dover Strait, Desmarest on 
 cutting through of, 143. 
 
 Dufrenoy, P. A., 421, 456. 
 
 Dykes, 306 ; Hall's discovery of 
 origin of, 321 ; chilled margins 
 of, noted by him, 321. 
 
 Earth, varied history of the, 5 \ 
 speculation as to early history 
 of, 59-61, 65,79, 8l > 8 4 8 9> 
 90 ; evidence for evolution of, 
 192. 
 
 Earthquakes, frequent in Medi- 
 terranean basin, 9 ; ancient 
 Greek explanations of, 13, 14; 
 Roman poets and philosophers 
 on, 1 6 ; nature of motion of, 
 discussed by Seneca, 23 ; ideas 
 of the ancients concerning, 
 27; Hooke on, 69, 71 ; Ray 
 on, 75 ; Descartes on, 80 ; 
 Leibnitz on, 82 ; Fuchsel on, 
 199 ; of Lisbon, 273, 275 ; 
 Michell's work on, 273 ; 
 modern research regarding, 
 279. 
 
 Eaton, A., 435, 459. 
 
Index 
 
 477 
 
 Edinburgh in the latter half of 
 the eighteenth century, 285 ; 
 geological environment of, 287, 
 328 ; Royal Society of, 288, 
 316 ; convivial clubs of, 288 ; 
 School of Geology established 
 at, 325. 
 
 Egypt, geological changes ob- 
 served by the Ancients in, 28, 
 
 29>.33> 3". 
 Electricity invoked to account for 
 
 volcanoes and earthquakes, 257, 
 
 272. 
 
 Elephants, fossil, of Siberia, 178. 
 lilie de Beaumont, 417, 421,456. 
 Empedocles, a martyr to science, 
 
 27. 
 Encyclopedic Methodique, 107, 168, 
 
 169. 
 
 Eocene, 404. 
 Eratosthenes, 33. 
 Erzgebirge, geology of the, 196. 
 Ethiopia, 32. 
 Etna, 10, 17, 18, 19,25, 27,39,' 
 
 323- 
 
 Europe, International Geological 
 Map of, 458. 
 
 Evolution, as displayed in his- 
 tory of the earth, 5, 192 ; 
 of organic types, 84, 87 ; 
 Lamarck on, 350; opposition 
 of Cuvier to doctrines of, 374. 
 
 Evolutionists, 472. 
 
 Experiment in Geology, 1 90, 317. 
 
 Falloppio on Fossils, 52. 
 
 Faujas de St. Fond, 174, 255,327. 
 
 Featherstonhaugh, G. W., 421, 
 
 460. 
 
 Ferguson, Adam, 285. 
 " Figured " or " Formed " Stones, 
 
 45 6 9> 74 77> 8 3 97> IOO > 
 102, 119. 
 Fitton, W. H., 239, 328, 331, 
 
 394> 397- 
 Fleming, Rev. John, 330. 
 
 Floetz rocks, 196, 214, 218, 220, 
 
 222, 225, 231, 232,408, 409. 
 
 Flood. See Deluge. 
 
 Forbes, D., 467. 
 
 Forbes, E., 457. 
 
 Forbes, J. D., 447. 
 
 Forchhammer, G., 421. 
 
 " Formations " in Geology, 
 Fiichsel on, 199 ; Werner on, 
 212, 230, 370 ; Cuvier and 
 Brongniart on, 370. 
 
 Fortis, J. B. A., 174. 
 
 Fossil, original application of the 
 term, 215, 355 ; modern signi- 
 fication of, first assigned by 
 Lamarck, 355; and afterwards 
 universally adopted, 400. 
 
 Fossils, deductions of the 
 Ancients from, 33 ; arouse 
 attention in the Middle Ages, 
 43 ; controversy as to nature 
 of, 45, 48, 69, 97 ; regarded 
 as "sports of Nature," 45, 53, 
 74, 83, 98 ; claimed to be 
 really of organic origin, 5 
 51, 52, 54, 55, 60,61,67, 69, 
 83, 100, 1 1 8, 1 20, 200 ; early 
 illustrated works on, 67, 69, 
 76, 77, 98, 100, 102 ; include 
 extinct types, 84, 364 ; show 
 a succession of species, 84, 92, 
 l8 9 J 93 374; growth of 
 study of, 98, 100, 101, 102, 
 104, 117, 1 1 8, 119, 196, 200, 
 336, 338, 34 2 > 349>355> 3^4, 
 369, 3 86 > 396, 4 01 5 littoral 
 and pelagic, 344, 355, 358; 
 chronological significance of, at 
 last recognised, 406. 
 
 Fouque, F., 39, 271, 467. 
 
 Fracastoro on Fossils, 5 I . 
 
 France, rise of geology in, 104 ; 
 discovery of old volcanoes in, 
 127, 141, 146; leading position 
 in geology early acquired by, 
 140, 157. 
 
47 8 
 
 Index 
 
 Freiberg, Mining School of, 204, 
 
 206, 208, 237, 239. 
 Fiichsel, G. C., 197-201, 233, 
 
 336, 4 01 - 
 Fusion, Hall's experiments on, 
 
 3I9 322. 
 
 Generelli, expositor of Moro, 65, 
 126. 
 
 Geognosy of Werner, 211. 
 
 Geological changes in the past, 
 views of the Ancients regard- 
 ing, 33- 
 
 Geological Maps, history of, 449. 
 
 Geological nomenclature, un- 
 systematic growth of, 407. 
 
 Geological Record, imperfection 
 of the, 439. 
 
 Geological Sections, 185, 193, 
 196, 198. 
 
 Geological Society of London, 
 
 2 97>.39 8 > 4 I 3>.4 I 7>423 ; 
 
 Geological succession, doctrine of, 
 59, 192, 201, 232, 250, 333. 
 
 Geological Survey of Great Bri- 
 tain, volcanic researches of, 
 270 ; work of, among Cambrian 
 and Silurian formations, 426 ; 
 foundation and objects of, 456. 
 
 Geological time, Buffon on, 91 ; 
 Lamarck on, 356 ; Darwin on, 
 
 439-. 
 Geologists, varied avocations of, 
 
 468. 
 
 Geology, historical method in, 
 2, 59, 90, 162, 192 ; and 
 speculation, 3, 6 ; and super- 
 stitions, 6 ; earliest pioneers 
 of, 7 ; Palasontological, first be- 
 ginnings of, 107, 117,118, 119, 
 1 39 ; modern development of, 
 
 349.. 355, 358, 364, 4oi ; 
 Physiographical, early observa- 
 tions in, 121, 1 60, 162 ; Vol- 
 canic, 127, 133, 140, 147, 162 
 [see also Volcanoes] ; first use 
 
 of term, 186 ; experimental 
 research in, 190, 317; Strati- 
 graphical, rise of in France, 
 333; in England, 378 ; re- 
 markable advance of, 400,438 ; 
 rise and development of Gla- 
 cial, 442 ; rise of Petrograph- 
 ical, 462 ; lies open to all 
 observers, 469. 
 
 Germany, basalts of, 147, I57 r 
 160, 221, 242, 249; ancient 
 volcanic rocks of, 271. 
 
 Gesner, Conrad, 45. 
 
 Giant's Causeway, 146, 147, 150. 
 
 Giraud-Soulavie, 338-341, 401. 
 
 Glacier action, Playfair on, 314, 
 442 ; in Britain, 446, 447. 
 
 Glaser, G., 451. 
 
 Glass, Hall's observations on slow 
 cooling of, 319. 
 
 Gneisses, Pre-Cambrian, 435. 
 
 Granite, De Saussure on, 188; 
 Werner on, 214, 230, 232; 
 Von Buch on, 251 ; Hutton 
 on, 290, 307 ; Lamarck on, 
 362. 
 
 Greece, earliest geological ideas 
 in, 7, 28, 33 ; subject to earth- 
 quakes, 13. 
 
 Greenough, G. B., 336, 453, 
 456. 
 
 Greywacke, 409, 410, 429. 
 
 Griffith, R., 455. 
 
 Guettard, J. E., early career of, 
 105 ; drawn to Geology 
 through Botany, 106 ; neglect 
 of work of, 1 08 ; early min- 
 eralogical surveys of, 1 1 o ; on 
 geology of Paris basin, 1 1 6 ; 
 palaeontological work of, 1 1 7, 
 1 1 8, 119, 140; on physio- 
 graphy, 121; on effects of rain 
 and springs, 121 ; on work of 
 the sea, 122 ; on rivers, 123 ; 
 on the sea-bottom, 1 24 ; on 
 limit of wave-erosion, 125 ;. 
 
Index 
 
 479 
 
 on denudation, 126, 139, 159; 
 volcanic discovery made by, 
 127, 1 40; on Basalt, 135,149, 
 223 ; his character as drawn 
 by Condorcet, 137; his service 
 in regard to palaeontological 
 geology, 401. 
 
 Haidinger, W., 252. 
 
 Hall, Sir James, 292, 298, 302, 
 313, 317-325, 328. 
 
 Harz, geology of the, 196. 
 
 Hauer, Franz Ritter von, 254. 
 
 Hay-Cunningham, R. J., 269. 
 
 Hayden, F.V., 4 6i. 
 
 Heat, effects of, influenced by 
 pressure, 301, 323. 
 
 Hercules in geological myths, 7. 
 
 Herodotus, geological conceptions 
 of, 7 ; on the Nile, 28, 32, 36; 
 on fossil shells, 33. 
 
 Hooke, Robert, on methods of 
 research in natural science, 49 
 note ; his contributions to geo- 
 logy, 68; on change of the 
 earth's centre of gravity, 70 ; 
 on the former length of a day 
 and of a year, 70 note; on 
 fossils as geological records, 71; 
 on volcanoes, 72. 
 
 Homer, Leonard, 297. 
 
 Homes, M., 254. 
 
 Humboldt, A. von, 245, 246, 
 
 447- 
 
 Hunt, T. S., 436. 
 
 Huronian rocks, 436. 
 
 Hutton, J., 188, 191, 218, 258; 
 birth and early training of, 28 1 ; 
 takes to farming, 282, 284 ; 
 led to take interest in geology, 
 283 ; goes to Flanders, 283 ; 
 settles in Edinburgh, 284 ; his 
 scientific acquirements, 286 ; 
 his experiment on the eating 
 of snails, 288; his Theory of the 
 Earth, published, 289, 294; on 
 
 igneous rocks, 259, 290 ; his 
 geological excursions, 291 ; on 
 the significance of an uncon- 
 formability among rocks, 291; 
 his personal characteristics, 293 ; 
 attacked by De Luc and Kir- 
 wan, 296, 329; account of his 
 system, 298 ; on composition 
 of the land, 300; on action of 
 subterranean heat, 301 ; on 
 supposed igneous origin of 
 flint, 301, 361 ; on influence of 
 pressure on rocks in modifying 
 effects of heat, 301, 323; on 
 disturbance of strata, 302 ; on 
 the cause of these disturb- 
 ances, 303; on origin of vol- 
 canoes, 304 ; on whinstone, 
 305; on granite, 307; on min- 
 eral veins, 309; on metamor- 
 phism, 310; on the degradation 
 of the land, 311; his reliance 
 on observation, 315; his circle 
 of friends, 315 ; his relation 
 to the doctrine of geological 
 succession, 334. 
 
 Ice, disputed action of, in Post- 
 Tertiary Geology, 445, 448. 
 
 Infiltration in the consolidation 
 of rocks, Lamarck on, 361. 
 
 Ireland, Griffith's Map of, 453. 
 
 Ischia, 20. 
 
 Islands, Strabo on origin of, 20 ; 
 Ovid on, 38. 
 
 Jameson, R., 211, 213, 218, 219, 
 226, 227, 239, 264, 265, 326, 
 402. 
 
 {amieson, T. F., 449. 
 apan, geological and seismolog- 
 ical surveys of, 457. 
 
 {enzsch, G., 467. 
 ukes, J. B., 313. 
 
 Jurassic formations, 381, 392, 
 441. 
 
480 
 
 Index 
 
 Jussieu, the Brothers, 106. 
 
 Keferstein, C., 197, 201, 222, 
 244, 408. 
 
 Kennedy, Robert, 322. 
 
 King, Clarence, 461. 
 
 Kirwan, R., 296, 316, 329. 
 
 Knorr, G. W., his plates of fos- 
 sils, etc., 101. 
 
 Lake District, ancient volcanic 
 rocks of, 266. 
 
 Lake Superior, pre - Cambrian 
 rocks of, 435. 
 
 Lamanon, 343, 371. 
 
 Lamarck, early career of, 345 ; 
 devotes himself to botany, 347; 
 publishes his Flore Franfaisc, 
 347 ; becomes Professor of 
 Zoology, 348 ; his contribu- 
 tions to geology, 349; founder 
 of invertebrate Palaeontology, 
 349 ; publishes his Hydrogeo- 
 k&*> 35 5 contributions to 
 evolution, 350; on origin of 
 mountains and valleys, 351 ; 
 on action of terrestrial waters, 
 353; on origin of the ocean- 
 basin, 353 ; on the use of 
 organic remains in the rocks, 
 355? 358 ; on the order and 
 antiquity of Nature, 356 ; on 
 antiquity of the earth, 356 ; 
 on interchange of land and sea, 
 3 5 7 ; on origin of the calcareous 
 material in the earth's crust, 
 358; on origin of limestone, 
 359 ; on the condition and 
 thickness of the earth's crust, 
 359; on the Pouvoir de la 
 Vie, 360 ; on consolidation of 
 rocks, 361; on granite, 362; 
 fate of his Hydrogeologte, 374; 
 his services to palaeontology, 
 401. 
 
 Land, submergence and elevation 
 of, 20, 34, 37; gain of, by 
 river deposits, 28, 29. 
 
 Landslips, Guettard on, 122. 
 
 Lang, K. N., his Historia Lapl- 
 dum, 98. 
 
 Lapworth, Prof. C., 441. 
 
 Laurentian rocks, 436. 
 
 Lava, Hutton on " unerupted," 
 
 35; 
 Lavoisier, 1 15, 343. 
 
 Legends, geological origin of 
 
 some, 6. 
 Lehmann, J. G., 180, 195, 233, 
 
 33<5> 401- 
 
 Leibnitz, cosmology of, 8i; re- 
 cognized the co-operation of 
 hypogene and epigene forces in 
 geological history, 82 ; on 
 earthquakes and volcanoes, 82; 
 on fossils, 83. 
 
 Leonhard, K. C. von, 262. 
 
 Lesley, J. P., 460. 
 
 Lhuyd, Edward, on Fossils, 77, 
 117. 
 
 Lias, outcrop of, traced by Strange, 
 337; zonal stratigraphy of, 
 
 .441. 
 Life, speculations on evolution of, 
 
 ^87. 
 
 Linnaeus, 189. 
 Lipari Isles, 15, 20. 
 Lister, Martin, on fossils, 76, 
 336 ; on mineralogical maps, 
 
 449- 
 
 Littoral fossils, 344, 355, 358. 
 
 Logan, W. E., 435. 
 
 Lonsdale, W., 431. 
 
 Lucretius, cited, 13 ; on earth- 
 quakes, 1 6. 
 
 Lyell, C., 159, 311, 313, 403, 
 411, 414. 
 
 Macculloch, J., 261, 454. 
 Maclaren, C., 269. 
 Maclure, W., 435, 458. 
 
Index 
 
 i 
 
 Maillet, Benoit de, his Telliamed, 
 
 84. 
 
 Majoli on Fossils, 53, 64. 
 Malesherbes, C. G. de L., 128, 
 
 145. 
 
 Mallet, R., 277. 
 Man, speculations as to origin of, 
 
 88. 
 Maps, earliest geological, 77, III, 
 
 112, 115, 139, 198, 449. 
 
 Mattioli, on the materia pinguis, 
 
 5 2 : 
 
 Mediterranean basin, favourable 
 for the study of geological 
 features, 9, 10, 1 1. 
 
 Mercati on Fossils, 52. 
 
 Metamorphic rocks, 436. 
 
 Metamorphism, Hutton on, 310. 
 
 Michell, J., 273, 277, 378. 
 
 Michel-Levy, A., 271, 467. 
 
 Milne, J., 279. 
 
 Mineral and Fossil collections, 
 early examples of, 52, 68, 78, 
 
 98, 101, 102. 
 
 Mineralogy, early cultivation of, 
 140 ; Werner's services to, 
 
 2IO. 
 
 Mines, foundation of British 
 School of, 456, 457. 
 
 Miocene, 404. 
 
 Monte Nuovo, 47, 61. 
 
 Montlosier, Comte de, 159, 174, 
 248, 257. 
 
 Moro, Anton-Lazzaro, his geo- 
 logical theories, 61. 
 
 Mountains, geological influence 
 of, 10; origin of, 57, 90; dif- 
 ferent ages of, 57; Pallas on 
 formation of, 180; scenery of, 
 formerly considered repulsive, 
 182; de Saussure's success in 
 kindling a love of, 182 ; La- 
 marck on origin of, 351. 
 
 Murchison, R. I., 159; early re- 
 searches of, on ancient volcanic 
 rocks, 268, 420; his birth and 
 
 early career, 412 ; becomes a 
 geologist, 41 3 ; begins an attack 
 on the " interminable Grey- 
 wacke," 414 ; establishes the 
 "Silurian system," 418; associ- 
 ated with Sedgwick in found- 
 ing the Devonian system, 429; 
 personal characteristics of, 433 ; 
 appointed Director-General of 
 Geological Survey, 457. 
 
 Murray, Alexander, 436. 
 
 Myths, geological origin of, 6, 7. 
 
 Naumann, C. F., 402. 
 Neptunists, 218, 246, 247, 257, 
 
 259, 262, 269, 328, 331. 
 Newberry, J. S., 461. 
 Nicol, W., 463, 465. 
 Nile, River, u, 28, 29, 32, 36. 
 
 Ocean, theory of a former uni- 
 versal, 60, 62, 90, 214, 217, 
 220, 230. 
 
 Old Red Sandstone, 408, 430, 
 
 432. 
 
 O/<?<?//#.r-zone, 442. 
 
 Omalius d'Halloy, J. B., 377, 402. 
 
 Olivi on Fossils, 53. 
 
 Oolitic formations, 381, 392,441. 
 
 Oppel, Dr. A., 441. 
 
 Organic remains in relation to 
 the doctrine of geological suc- 
 cession, 335; as guides in stra- 
 tigraphy, 440 [See Fossils]. 
 
 Ovid on the Pythagorean philo- 
 sophy, 37; on islands, 38. 
 
 Packe, C, 450. 
 
 Palaeontology. See Geology, 
 Palasontological. 
 
 Palaeozoic rocks, elaboration of 
 stratigraphy of, 410-432 ; vol- 
 canic series, 264, 266, 267. 
 
 Palassou, 452. 
 
 Palissy, Bernard, 104, 1 1 8. 
 
 Pallas, P. S., 178. 
 
 2H 
 
482 
 
 Index 
 
 Paris, Academy of Sciences of, 
 107, 114, 137, 155, 173,234.; 
 influence of Tertiary Basin of, 
 on geological progress, 1 1 6, 
 341-345, 363-372- 
 
 Pelagic fossils, 344, 355, 358. 
 
 Peneius, River, n. 
 
 Percy, J., 457. 
 
 Perry, A., 277. 
 
 Petrography, earliest essay in, 1 6 ; 
 de Saussure's experimental 
 work in, 189 ; Werner's con- 
 tributions to, 213, 230, 238 ; 
 modern development of, 462. 
 
 Phillips, John, 381. 
 
 Phlegraean Fields, 19. 
 
 Physical Geography, Desmarest 
 on, 168. 
 
 Physiography. See Geology, 
 Physiographical. 
 
 Plants and Animals, Lamarck on 
 geological action of, 260. 
 
 Plastic force in Nature, supposed 
 to imitate organic bodies, 16, 
 
 45 So, 5 2 > 77. 
 
 Plato on source of rivers, 28. 
 
 Playfair, J., 259, 261, 281, 287, 
 290, 291, 292,295, 296, 297, 
 310, 312, 314,316, 325, 351, 
 361, 442. 
 
 Playfair, Lyon, 457. 
 
 Plication, Hall's experimental 
 illustration of, 325. 
 
 Pliny, the Elder, 26 ; on earth- 
 quakes and volcanoes, 27. 
 
 Pliocene, 404. 
 
 Plot, Robert, on Fossils, 77. 
 
 Plutonists, 218, 259, 262, 269, 
 328, 331. 
 
 Po, River, 1 1 . 
 
 Pompeii, earthquake at, 22, 23, 
 27. 
 
 Porphyry, Werner on, 214; 
 Hutton on, 305. 
 
 Poseidon, in geological myths, 7. 
 
 Powell,]. D., 461. 
 
 Pre-Cambrian rocks, 435. 
 
 Present, as a Key to the Past, 
 298. 
 
 Pressure, influence of, in modify- 
 ing effects of heat, 301, 323. 
 
 Primitive rocks, 180, 195, 214, 
 222, 230,232, 310,409,435; 
 Lamarck's rejection of the term, 
 359> 362. 
 
 Primordial Fauna, 428. 
 
 Puy de Dome, 1 30. 
 
 Pyritous strata, spontaneous com- 
 bustion of, 76, 94, 274. 
 
 Pythagoras on the system of 
 Nature, 37. 
 
 Quenstedt, F. A. von, 441. 
 
 Ramsay, A. C., 313, 435, 439, 
 
 449> 457- 
 
 Raspe, R. E., 173. 
 
 Rath, G. vom, 467. 
 
 Ray, John, influence of orthodoxy 
 on, 73 ; his views on denuda- 
 tion, 74, 126; his opinions 
 on fossils, 74 ; on earthquakes 
 and volcanoes, 75 ; cited, 78. 
 
 Reuss, F. A., 402. 
 
 Rhineland, Basalt of, 147, 148, 
 1 60. 
 
 Rhinoceros, fossil, of Siberia, 1 79. 
 
 Rhone, River, 1 1. 
 
 Richardson, Dr. (Portrush), 328. 
 
 Richardson, Rev. B., 388. 
 
 Rivers, views of the Ancients 
 on geological action of, 28 ; 
 Guettard on, 123 ; Hutton 
 and Playfair on, 312; Lamarck 
 on, 351. 
 
 Rochefoucault, Due de la, 144, 
 145. 
 
 Rocks, threefold classification of, 
 180, 195, 196, 214; chrono- 
 logical sequence of, 194, 198 ; 
 geological succession of, 192, 
 201, 232, 250, 333 ; Lamarck 
 
Index 
 
 483 
 
 on consolidation of, 361 ; 
 
 method of making thin slices 
 
 of, for microscopical examina- 
 
 tion, 463. 
 
 Rogers, H. D., 460. 
 Rogers, W. B., 421, 460. 
 Rome, earliest geological ideas 
 
 in, 7. 
 
 Rose, G., 467. 
 Rosenbusch, H., 467. 
 Rouelle, G. F., 342. 
 Royal Society, Curatorship of 
 
 Experiments in, 68 ; foreign 
 
 member of, 99, 100 ; collects 
 
 earthquake records, 272, 274; 
 
 assists Mallet's investigation 
 
 of earthquakes, 278. 
 Russia, early scientific survey of, 
 
 Sand, experiment in consolidation 
 of, 324. 
 
 Santorin, volcanic action at, 24. 
 
 Saussure, H. B. de, on valleys, 
 159 ; on the Alps, 181 ; in- 
 fluence of, in removing the 
 popular dislike of mountain 
 scenery, 182 ; on granite, 185, 
 307 ; on disturbed strata, 187, 
 302 ; on erosion of valleys, 
 1 88 ; experimental researches 
 of, on rocks, 190. 
 
 Saxony, Basalt of, 147, 157, 160, 
 221, 242, 249. 
 
 Sea, early observations on former 
 presence of, n, 33, 34, 36, 
 
 37> 38, 43, So, 5 1 , 5 2 53 
 55, 59, 60, 62, 70, 71, 84, 
 85, 90, 104, 118; supposed 
 to have subsided into earth's 
 interior, 66, 90, 93 ; origin 
 of salinity of, 62, 82, 124; 
 absence of erosion much below 
 surface of, 125. 
 
 Secondary rocks, 180, 195, 378, 
 38i, 397, 399,408,470. 
 
 Sedgwick, A., researches of, on 
 ancient volcanic rocks, 266 ; 
 on W. Smith, 395 ; associated 
 with Murchison, 412, 423 ; 
 birth and career of, 421 ; be- 
 comes Woodwardian Professor 
 of Geology, 42 1 ; in the Lake 
 District, 423 ; in Wales, 424 ; 
 establishes the Cambrian system, 
 426 ; associated with Murchi- 
 son in forming the Devonian 
 system, 429 ; personal charac- 
 teristics of, 433. 
 
 Seismology, rise of, as a branch 
 of science, 277. 
 
 Seneca, his Natural Questions, 
 21 ; on the system of Nature, 
 21 ; on earthquakes, 22 ; on 
 volcanoes, 24. 
 
 Severinus, Peter, cited, 49. 
 
 Scheuchzer, J. J., geological writ- 
 ings of, 98-100. 
 
 Scotland, volcanic geology of 
 Western Isles of, 148, 256, 
 264 ; volcanic rocks of central, 
 264, 269, 287'; granite of, 
 291 ; unconformable rocks in, 
 292, 303 ; eruptive rocks in, 
 305 ; Macculloch's Geological 
 Map of, 454. 
 
 Scrope, G. P., 109, 128. 
 
 Siberia, fossil pachyderms in 
 frozen soil of, 178. 
 
 Silesia, Basalt of, 147, 160. 
 
 Silica, Lamarck's view of relative 
 importance of, 361. 
 
 Silurian fossils, first published 
 illustrations of, 1 17. 
 
 Silurian system, established by 
 Murchison, 418 ; his mono- 
 graph on, 420 ; application of 
 zonal stratigraphy to, 441. 
 
 Smith, William, birth and early 
 career of, 381; becomes land- 
 surveyor, 382; his first geolog- 
 ical expedition, 383 ; acquires 
 
4 8 4 
 
 Index 
 
 a detailed knowledge of the 
 Secondary formations, 386, 
 388; his "Table of Strata," 
 
 388 ; collects materials for a 
 geological map of England, 
 
 389 ; settles in London, 390 ; 
 publishes his Map, 391; value 
 of his work among the Jurassic 
 formations, 392 ; involved in 
 financial difficulties, 393 ; re- 
 ceives the Wollaston medal, 
 395; his personal appearance, 
 395 ; his publications, 396 ; 
 his services to Stratigraphy, 
 401 ; limits of his stratigraph- 
 ical knowledge, 409 ; descrip- 
 tion of his Map, 452. 
 
 Smyth, Warington W., 457. 
 
 Soland, Aime" de, 108. 
 
 Somma, dykes of, 321. 
 
 Sorby, H. C., 465. 
 
 Spallanzani, 256. 
 
 Springs, early conceptions of 
 origin of, 28, 31, 6 1, 74. 
 
 Staffa, 148. 
 
 Stars, supposed influence of, in 
 the production of "figured 
 stones," 45, 50, 52. 
 
 Steno, Nicholas, career of, 53; 
 on fossil sharks' teeth, 54; his 
 geological treatise, 5 5 ; on stra- 
 tified formations, 55 ; on dis- 
 turbances of strata, 56, 57, 
 302, 303; on erosion of strata, 
 57; on Fossils, 58; on geolog- 
 ical history, 59. 
 
 Strabo on Vale of Tempe, 8 ; on 
 River Alpheus, 8 ; on statues 
 said to have been brought from 
 Troy, 8; on the Memnonium, 
 9; on the exodus of the Cim- 
 bri, 9 ; character of his Geo- 
 graphy, 1 8 ; on volcanoes and 
 earthquakes, 1 8, 19, 304; on 
 origin of islands, 20; on hydro- 
 graphy of Mediterranean basin, 
 
 29 ; on deltas, 30 ; on rivers, 
 31; on displacing action of 
 vegetable roots, 31; on the 
 final destruction of the human 
 race, 32 ; on fossils, 34 ; on 
 former geological changes, 36. 
 
 Strachey, John, 194, 378. 
 
 Strange, John, 336. 
 
 Strata, inferences from vertical, 
 185, 188, 199, 221. 
 
 Stratification, Steno on, 55; dis- 
 turbances of 57; de Maillet 
 on, 86 ; de Saussure on, 185, 
 1 88; Strachey on, 194; 
 Fuchsel on, 198. 
 
 Stratigraphy, early progress of, 
 56, 194, 198, 333. 
 
 Strato on geological changes in 
 
 Egypt, 33- 
 
 Stukeley, W., 272. 
 
 Supernatural, decay of the, in in- 
 terpretations of topographical 
 features, 8. 
 
 Surveys, national geological, 456. 
 
 Tempe, explanations of origin of 
 
 Vale of, 7. 
 Tertiary Rocks, 180, 195, 341, 
 
 345, 363, 397, 399> 44, 4 8 , 
 
 470. 
 
 Text books of Geology, 401. 
 Theophrastus on stones, 1 6 ; on 
 
 a plastic virtue in Nature, 16, 
 
 , 45 * 
 Thessaly, draining of lake in, 7. 
 
 Thuringer Wald, geology of the, 
 197. 
 
 Tiber, River, 1 1. 
 
 Transition Rocks of Werner, 214, 
 220, 231, 409, 470 ; early re- 
 searches in, 410; Murchison's 
 researches among, 414, 417, 
 419, 429; of America, 459, 
 460. 
 
 Trappean Rocks, 264, 265, 267. 
 
 Travel, rise of Geological, 176. 
 
Index 
 
 Trilobites, first recognition of, 
 117. 
 
 Uniformitarianism in Geology, 
 
 i.99 43> 47 2 - 
 United States, volcanic geology 
 
 of, 271; geologists of, on river 
 
 erosion, 313 ; early geological 
 
 maps of, 458. 
 Universal formations of Werner, 
 
 212, 214, 215, 230. 
 
 Vallisneri, Antonio, 60. 
 
 Valleys, origin of, 57, 94, 159, 
 188, 312, 351. 
 
 Vanuxem, L., 460. 
 
 Venetz, J., 442. 
 
 Vesuvius, 10 ; recognised by 
 Strabo to be a volcano, 1 8 ; 
 eruption of in A.D. 79, 23, 27; 
 experiments in fusion of lavas 
 of, 322. 
 
 Vinci, Leonardo da, 50. 
 
 Vivarais, geology of the, 338. 
 
 Voigt,J. K. W., 223. 
 
 Volcanic geology, 127, 133, 140, 
 162. 
 
 Volcanic rocks, 195 ; interca- 
 lated among ancient geological 
 formations, 259, 339 ; ascer- 
 tained to be of all geological 
 periods, 263 ; Tertiary, 260 ; 
 Carboniferous, 264, 271 ; Old 
 Red Sandstone and Devonian, 
 264, 266, 270, 271 ; Silurian, 
 266, 267 ; Cambrian, 267 ; 
 Permian, 271. 
 
 Volcanoes, in Mediterranean 
 basin, 10; Aristotle's explana- 
 tion of, 15 ; Lucretius on, 17; 
 as safety-valves, antiquity of the 
 doctrine of, 19 ; Seneca on, 24; 
 appealed to in the Middle Ages 
 as agents in the accumulation 
 of the fossiliferous formations, 
 47, 53, 62, 64 ; supposed to 
 
 be due to combustion of in- 
 flammable substances, 25, 56, 
 57> 60, 73, 75, 80, 82, 93, 
 133, 156, 225; attributed to 
 spontaneous decomposition of 
 iron-pyrites, 76, 94, 274; sup- 
 posed modern origin of, 82, 
 93, 224, 225, 258 ; first dis- 
 covery of extinct, in France, 
 127-135, 339 ; connected with 
 internal heat of the globe, 255 ; 
 supposed connection of with 
 electricity, 258. 
 
 Vulcanists, 133, 136, 218, 224, 
 246, 247, 252, 257,262, 327, 
 33*. 
 
 Walch, J. E. I., his Das SteinreicA, 
 101 ; continued G. W. Knorr's 
 work on Fossils, 102. 
 
 Wales, volcanic geology of, 267, 
 268, 270. 
 
 Wallerius, 189. 
 
 Weather, influence of on earth- 
 quakes and volcanoes, 14, 19, 
 27. 
 
 Webster, T., 396. 
 
 Werner, A. G., forestalled by 
 Guettard in his explanation of 
 origin of Basalt, 136, 156,226; 
 opposed volcanic theories, 175, 
 222, 225; on aqueous origin 
 of granite, 185, 290, 307 ; 
 wide influence of, 201 ; popu- 
 larity of, 202; childhood and 
 education of, 203; training of, 
 in mining, 204; at Leipzig 
 University, 205; first published 
 essay of, 225 ; appointed to 
 Freiberg Academy, 206 ; per- 
 sonal appearance and charm of, 
 207; style of lecturing of, 208, 
 233, 235 ; character of his 
 teaching, 209, 238 ; method- 
 ical characteristics of, 209, 230, 
 231; mineralogical nomencla- 
 
4 86 
 
 Index 
 
 ture of, 210; "universal for- 
 mations" of, 212, 213, 214, 
 215, 230; his classification and 
 chronological arrangement of 
 rocks, 213, 230, 333 ; his ex- 
 planation of the origin of rocks, 
 215; his theory of a universal 
 ocean and of chemical precipi- 
 tates, 214, 217, 220; on dis- 
 turbance in the earth's crust, 
 221, 228, 302 ; his contro- 
 versy about Basalt, 223, 226 ; 
 on nature of volcanoes, 224, 
 226; on veins, 229, 308, 309; 
 his dislike of writing, 233 ; 
 source of his influence, 236; 
 his services to science, 237, 
 462 ; loyalty of his followers 
 to, 240. 
 
 Wernerian School of Geology, 
 237, 239 ; decline of, 241, 
 244, 246, 250, 251,252,254, 
 330. 
 
 Wernerian Society, foundation 
 
 of, 327, 33- 
 
 Wind, important part assigned 
 to, by the ancients in subter- 
 ranean phenomena, 14, 16, 19, 
 23, 25, 26, 27, 38, 271. 
 
 Whinstone, Hutton on, 305 ; 
 Hall's experiments with, 320 ; 
 resembles lava, 321. 
 
 Whiston, W., his New Theory of 
 the Earth, 67. 
 
 Whitehurst, John, 380. 
 
 Widenmann, J. F. W., 224. 
 
 Witham, H., 463. 
 
 Woodward, John, his geological 
 views, 67. 
 
 Xanthus the Lydian, 33. 
 Xenophanes of Colophon, 33. 
 
 Zirkel, F., 467. 
 
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