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school of geologists that eminent rank which has hitherto been 

 accorded to it. 



A quarter of a century has now just elapsed since the Royal 

 Medal was awarded to Sir Charles Lyell for his ' Principles of 

 Geology.' 



It was his good fortune to be associated in his earliest years with 

 those from whom he imbibed a love of Natural History, and who 

 fostered those habits of accurate observation, the successful appli- 

 cation of which to geological problems is one of the prominent 

 features of his scientific writings. This it was that gave so much 

 value and promise to his first labours on the geology of the marls 

 and freshwater formations of Angus, his native district ; that enabled 

 him to appreciate to the full, the bearings, not only of palaeontology 

 (the importance of which had been already recognized), but also of 

 a large class of facts, of almost equal value in relation to the philo- 

 sophy of geology, conducting him through a series of researches, 

 the merit of originating which is wholly his own : I allude to 

 the permanence or mutability of animal and vegetable forms, to 

 their reciprocal action, and to the laws which govern their repro- 

 duction and dispersion ; and we hence owe to him both the enun- 

 ciation and the demonstration of the doctrine, that the history of 

 many ancient geographical changes and geological phenomena is only 

 to be arrived at after a careful study of the present distribution of 

 organic beings. 



The same line of research led Sir C. Lyell, in conjunction with 

 M. Deshayes, to that method of classifying strata, and hence of 

 comparing formations, by the relative proportions of living organisms 

 they contain, a method which has proved of such eminent service to 

 geologists. By its aid, and after untiring diligence in collecting, and 

 equal perseverance and sagacity in comparing the results of his own 

 and other collections, with those in the various museums of Europe 

 and America, he has not only largely contributed to classify the 

 tertiary rocks of both continents, but has further given us the first 

 clear idea of the relations of modern strata separated by the great 

 valley of the Atlantic Ocean. 



In immediate connexion with these inquiries, and no doubt 

 directly originating in his mind from that principle to which he 

 has steadfastly adhered, of endeavouring to account for past changes 



