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REVIEW. 



A Guide to Geology, by John Phillips, F.R.S., G.S., Professor 0/ Geology 

 in King's College, London, Sfc. Second edition, 1835. \2r,w. pp. 108. 

 London, Longman & Co. 



AVe liave mncli satisfaction in reconi mending to our readers tliis very 

 convenient elementary work, on n science tlie daily increasing popularity 

 of wliicli lias long rendered desirable a compendious introduction, wliicli 

 should sufficiently place its great princi])les before the general reader, 

 without encumbering him with voluminous details. The present treatise 

 is indeed far less copious than the excellent manual of M. De la Beche (a 

 work of perpetual reference, absolutely indispensable to every one who 

 would enter into the whole field of Oeology) ; but is on that very account 

 so mucii better suited to the purposes of the more general student, on 

 whose attention it imposes only a small duodecimo of one hundred and 

 sixty-eight pages ; while it fully acquaints him with the nature and evidence 

 of those extraordinary facts as to the structure and history of our planet, 

 which this most interesting science has brought to light. It is divided 

 into four parts; in the first or introductory, we find a general statement of 

 the disposition and arrangement, in successive formations, of the strati- 

 fied rocks, forming nine-tenths of the crust of our globe, together with a 

 notice of the nnstratified rocks, by which the former arc occasionally 

 interrupted, and a recapitulation of the evidence which leads us to con- 

 sider the former as suliaqueous deposits, and the latter as igneous pro- 

 ducts. We have then an able sketch of the connection between Physical 

 Geography and Geology, and the manner in which " the surface of the 

 earth derives all its diversity of form and products, from the originally 

 different nature of its constituent rocks, the variety of dispositions into 

 which these have been thrown, and the consequent inequality of effect pro- 

 duced upon them by atmospherical and other modifying agencies," p. 31. 

 The second part is devoted to a more careful examination of the generali- 

 sations, to which we were introduced in the former : the proofs of the 

 subaqueous production of the land, and of the elevation of the present 

 continents by the agency of the volcanic eruptions which produced the 

 nnstratified rocks beforfi mentioned ; the evidence that these elevating 

 convulsions have affected different mountain chains at different periods, of 

 which the relative geological ages can be determined, by observing how 

 many of the successive formations have been affected by them, and which 

 (as having escaped these disturbing forces in every instance) appear to 

 have been subsequently deposited : a very masterly sketch of the general 

 phaenomena of the distribution of the various classes of organic remains 

 in the various strata, with the proofs that successive races of varying plants 

 and animals have occupied our planet at various periods, being preserved 



