1832.] Progress of Geological Science. 521 



Mr. Lyell has engaged the latter to co-operate with him in classing the terti- 

 ary formations chronologically, according to the relative number of existing species 

 in each group. Their joint labours will form a most valuable " Manual of Fossil 

 Conchology," which is announced as forthcoming in the third volume of Mr. Lyell's 

 " Principles of Geology." It was subsequent to these studies that the latter author 

 was prompted to continue his examination of the various causes still in operation on 

 the surface of the globe, which form the subject of his second volume. In tli3 former, 

 we were presented with the effects of inorganic forces ; in the second, we find an 

 abundance of facts connected with the fluctuations in the organic world. So ample 

 are the data in natural history, upon which the author has established his conclu- 

 sions, that they cannot fail to relieve him from the charge of visionary speculation*. 



Prof. Sedgwick felt alarmed, lest the gradual course of nature, upheld in the first 

 volume, should favor the doctrine of spontaneous generation and transmutation of 

 species, with all their train of monstrous consequences; but nothing can be fairer or 

 more impartial than the manner in which the untenable parts of Lamarck's dogmas 

 are refuted in the second volume, and the recent appearance of man upon our 

 planet, satisfactorily confirmed. 



Turning now from the view of gradual changes, upon which we have impartially 

 quoted the opinions of an opponent and of an advocate, we come to the hypothesis 

 of mundane convulsions, where, as might be expected, the late and the actual Presi- 

 dents change sides. In the words of the former, the theory of M. Elie de Beaumont 

 si thus describedf: 



"M. Elie de Beaumont, by an incredible number of well conducted observations 

 of his own, combined with the best attested facts recorded by other observers, 

 has proved, that whole mountain chains have been elevated at one geological pe- 

 riod — that great physical regions have partaken of the same movement at the 

 same time — and that these paroxysms of elevatory force have come into action at 

 many successive periods. Distinguished as are his merits, he so far claims not an 

 undivided honour. But in the next great step of generalization, he reaches a posi- 

 tion where he stands entirely by himself. 



" Step by step, we had been advancing towards the conclusion — that different 

 mountain chains had been elevated at several distinct geological periods ; and by 

 a long series of independent observations, Humboldt, Von Buch, and other great 

 physical geographers, had proved — that the mountain chains of Europe might be 

 separated into three or four distinct systems ; distinguished from each other, if I 

 may so express myself, by a particular physiognomy, and, above all, by the differ- 

 ent angles made by the bearings of their component formations with any assumed 

 meridian. All the subordinate parts of any one system were shown to be parallel; 

 while the different systems were inclined at various angles to each other. 



" By an unlooked-for and most felicitous generalization, M. Elie de Beaumont 

 has now proved, that these two great classes of facts are commensurate to each 

 other ; and that each of these great systems of mountain chains, marked on the 

 map of Europe, by given parallel lines of direction, has also a given period of eleva- 

 tion, limited and defined by direct geological observations. The steps by which he 

 reaches this noble generalization are so clear and convincing, as to be little short 

 of physical demonstration. It forms an epoch in the history of our science ; and 

 I am using no terms of exaggeration when I say, that in reading the admirable 

 researches of M. de Beaumont, I appeared to myself, page after page, to be ac* 



* Phil. Mag. 377. f Anniversary Address, 1831, 



2 u 2 



