Silt CHARLES LYELL. 233 



candor and sincerity, in abandoning old ground and embracing new- 

 views, that is afforded in the whole history of science. In the earlier 

 editions of his works he accepted the current opinions in regard to 

 organic species and the past course of life upon earth, but, after a half- 

 century's study of the question, he became satisfied that these views 

 are untenable, and in the tenth edition of his " Principles of Geology," 

 published in 1867, he gave them up, and adopted the general view rep- 

 resented by Mr. Darwin. This great work he has again revised, and 

 th% eleventh edition has just made its appearance. All the later ques- 

 tions of this most interesting subject will there be found most ably and 

 fully discussed. We subjoin the notice of the work just published by 

 the Saturday Review : 



The great work of Sir Charles Lyell has too long and too authori- 

 tatively held its place as a classic in the literature of science to call for, 

 or even to admit, the expression of any estimate of its value. The 

 number of editions it has gone through may be taken as sufficiently at- 

 testing the concurrence of public taste and conviction with the appre- 

 ciative opinion of the more critical class of readers at home and abroad. 

 It may be hoped that the wide and increasing circulation of so valuable 

 a work has had, and is long destined to have, the effect of leavening the 

 mass of educated thought with its sound, careful, and conscientious 

 views of physical truth. While congratulating both the writer and 

 reader upon the issue of the eleventh edition of the ' Principles of 

 Geology,' we feel that our notice of its contents is almost of necessity 

 restricted to those portions of the work in which the author has seen 

 reason to amplify, to remodel, or to correct, what he had advanced in 

 former impressions. 



Within the last five years special attention lias been drawn to the 

 geological proofs of strongly-marked changes in the terrestrial climate 

 during long periods of time. In face of the additional facts and 

 corresponding theories which have thus divided the minds of geological 

 inquirers, Sir Charles Lyell has seen fit to recast those chapters of his 

 work which treated of the meteorology and climatic history of the 

 earth's surface, with a view especially to insist upon the paramount in- 

 fluence exerted in this direction by the relative distribution and height 

 of the land at successive periods. The balance of argument and re- 

 search has been such in the mean while as to confirm him more and 

 more in his conviction of the agreement and continuity of the forces at 

 work through all the vicissitudes of the earth's surface, from the earli- 

 est to the most recent geological ages. It is hardly necessary, perhaps, 

 to go further back, for the pedigree of the organic forms which for the 

 most part chronicle and attest the laws of succession, than to that Mio- 

 cene period in whose organic deposits the flora and fauna of all subse- 

 quent ages seem to have their ground and root. A superficial view of 

 the local changes of climate which are proved to have taken place 

 might have, and indeed has, induced the belief that causes no longer 



