NATURE 



n 



THURSDAY, MAY 25, 1S82 



CHARLES DARWIN^ 

 II. 



NO man of his time has exercised upon the science of 

 Geology a profounder influence than Charles Darwin. 

 At an early period he took much interest in geological 

 studies, and all through life, while engaged in other pur- 

 suits, he kept himself acquainted with the progress that 

 was being made in this department of natural know- 

 ledge. His influence upon it has been twofold. It arises 

 partly from the importance and originality of some of his 

 own contributions to the literature of the science, but 

 chiefly from the bearing of his work on other branches of 

 natural history. 



When he began to direct his attention to geological 

 inquiry the sway of the Cataclysmal school of geology was 

 still paramount. But already the Uniformitarians were 

 gathering strength and, before many years were past, had 

 ranged themselves under the banner of their great cham- 

 pion Lyell. Darwin, who always recognised his indebted- 

 ness to Lyell's teaching, gave a powerful impulse to its 

 general reception by the way in which he gathered from 

 all parts of the world facts in its support. He continually 

 sought in the phenomena of the present time the explana- 

 tion of those of the past. Yet he was all the while laying 

 the foundation on which the later or Evolutional school 

 of geology has been built up. 



Darwin's specially geological memoirs are not numer- 

 ous, nor have they been of the same epoch-making kind 

 as his biological researches. But every one of them 

 bears the stamp of his marvellous acuteness in observa- 

 tion, his sagacity in grouping scattered facts, and his 

 unrivalled far-reaching vision that commanded all their 

 mutual bearings, as well as their place in the general 

 economy of things. His long travels in the Beagle 

 afforded him opportunities of making himself acquainted 

 with geological phenomena of the most varied kinds. 

 With the exception of one or two minor papers written 

 in later years, it may be said that all his direct contribu- 

 tions to geology arose out of the Beagle voyage. The 

 largest and most important part of his geological work 

 dealt with the hypogene forces of nature — those that are 

 concerned in volcanoes and earthquakes, in the elevation 

 of mountains and continents, in the subsidence of vast 

 areas of the sea-bottom, and in the crumpling, foliation, 

 and cleavage of the rocks of the earth's crust. His re- 

 searches in these subjects were mainly embodied in the 

 " Geology of the Voyage of the Beagle" — a work which, 

 in three successive parts, was published under the 

 auspices of the Lords of the Treasury. 



The order chosen by Darwin for the subjects of these 

 three parts probably indicates the relative importance 

 with which they were regarded by himself. The first 

 was entitled "The Structure and Distribution of Coral 

 Reefs" (1S42). This well-known treatise, the most 

 original of all its author's geological memoirs, has be- 

 come one of the recognised classics of geological literature. 

 The origin of those remarkable rings of coral-rock in 

 mid-ocean had given rise to much speculation, but no 



1 Continued from p. 51. 



Vol.. xxvi. — No. 656 



satisfactory solution of the problem had been proposed. 

 After visiting many of them, and examining also coral- 

 reefs fringing islands and continents, he offered a theory 

 which for simplicity and grandeur strikes every reader with 

 astonishment. It is pleasant after the lapse of many 

 years to recall the delight with which one first read the 

 "Coral Reefs," how one watched the facts being mar- 

 shalled into their places, nothing being ignored or passed 

 lightly over, and how step by step one was led up to the 

 grand conclusion of wide oceanic subsidence. No more 

 admirable example of scientific method was ever given to 

 the world, and even if he had written nothing else, this 

 treatise alone would have placed Darwin in the very front 

 of investigators of nature. 



The second part was entitled "Geological Observations 

 on the Volcanic Islands visited during the voyage of 

 H.M.S. Bc.igle. together with some brief notices on the 

 geology of Australia and the Cape of Good Hope " (1844). 

 Full of detailed observations, this work still remains the 

 best authority on the general structure of most of the 

 regions it describes. At the time it was written, the 

 "Crater of elevation theory," though opposed by Constant 

 Prevost, Scrope, and Lyell, was generally accepted, at 

 least on the Continent. Darwin, however, could not 

 receive it as a valid explanation of the facts, and though 

 he did not adopt the views of its chief opponents, but 

 ventured to propose a hypothesis of his own, the observa- 

 tions impartially made and described by him in this 

 volume must be regarded as having contributed towards 

 the final solution of the question. 



The third and concluding part bore the title of " Geo- 

 logical Observations on South America " (1S46). In thi 

 work the author embodied all the materials collected by 

 him for the illustration of South American geology save 

 some which had already been published elsewhere. One of 

 the most important features of the book was the evidence 

 which it brought forward to prove the slow, interrupted 

 elevation of the South American continent during a recent 

 geological period. On the western sea-board he showed 

 that beds of marine shells could be traced more or less 

 continuously for a distance of upwards of 2000 miles, that 

 the elevation had been unequal, reaching in some places 

 at least to as much as 1300 feet, that in one instance at a 

 height of S5 feet above the sea, undoubted traces of the 

 presence of man occurred in a raised-beach, and hence 

 that the land had there risen 85 feet since Indian man 

 had inhabited Peru. These proofs of recent elevation 

 may have influenced him in the conclusion which he drew 

 as to the marine origin of the great elevated plains of 

 Chili. But at that time, there was a general tendency 

 among British geologists to detect evidence of sea-action 

 everywhere and to ignore or minimise the action of running 

 water upon the land. An important chapter of the volume, 

 devoted to a discussion of the phenomena of cleavage and 

 foliation, is well known to every student of the literature 

 of metamorphism. 



The official records of the Beagle did not, however, 

 include all that Darwin wrote on the geology of the 

 voyage. He contributed to the Transactions of the Geo- 

 logical Society (vol. v. 1840) a paper on the connection 

 of volcanic phenomena. In the same publication (vi. 

 1842) appears another, on the erratic boulders of South 



