EE VIEWS. 



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they may have sained in passing through previous formed rocks. Had it not been for 

 the outburst of such igneous rocks, our ' old and craggy earth,' as Cowper calls it, would 

 have been full of yawning chasms, and its solid crust would have presented an appearance 

 something similar to a clay-bank that has been exposed to a July sun. But the fluid molten 

 matter has been squirted from beneath into all the fissures which had been formed from tbe 

 contraction of the masses after their formation, and has bound and cemented them together. 

 Nay, were it not for the existence of such outlets to t he fieri/ reservoir below these volcanic 

 vents, our world could not have lived out half its days. These have been, in all stages of 

 its history, the safety-valves to let off the superfluous potency, instead of beiug pent up 

 and exploding the thin shell formed, by the stratified rocks, or causing the earth to 

 come to an untimely end by its disjointed continents wandering in several orbits through 

 space, in a manner similar to that hypothetical planet Pluto." 



Mr. Taylor has said here nothing new which, others have not said before, 

 but the passages we have set in italics will show the incongruity of the 

 items of which this igneous theory is compounded ; for how that which 

 has cemented together the fractures of the shell of our earth can be a means 

 of outlet for the liquid matter beneath, is not clearer than is the source of 

 the heat that made and maintains a molten core attributed to our planet. 

 As to the origin of these so-called igneous rocks, just let us put again t these 

 old parrot-repeated dicta what Sterry-Hunt, one of the best of modern 

 geologists, has recently written in his " Contributions to Lithology," in 

 Silliman's Journal. 



" I have already, in other places, expressed the opinion that the various eruptive 

 rocks have had no other origin than the softening and displacement of sedimentary de- 

 posits ; and have thus their sources within the lower portions of the earth's stratified 

 covering, and not beneath it. The theory which conceives them to have been derived 

 from a portion of the interior of the earth still retaining its supposed primitive condition 

 of igneous fluidity, is, in my opinion, untenable. It is not here the place to discuss the 

 more or less ingenious speculations of Phillips, Durocher, andBuusen as to tbe constitu- 

 tion of this supposed fluid centre, nor the more elaborate hypothesis of Sartorius von 

 Walterhausen as to the composition and arrangement of the matters in this imaginary 

 reservoir of Plutonic rocks. The immense variety presented in the composition of 

 eruptive masses, presents a strong argument against the notion that they are derived, as 

 these writers have supposed, from two or more zones of molten matter, differing in com- 

 position and density, and lying everywhere beneath the solid crust of the earth* which, 

 in opposition to the views of many modern mathematicians and physicists, the school of 

 geologists just referred to regard as a shell of very limited thickness. The view which I 

 adopt is one, the merit of which belongs, I believe, to Christian Keferstein, who, in his 

 ' Naturgeschichte des Erdkorpers,' published in 1834, maintained that all the unstrati- 

 fied rocks from granite to lava are products of the transformation of sedimentary strata, 

 in part very recent ; and that there is no vjell-defined line to be drawn between Neptu- 

 nian and Volcanic rocks, since they pass into each other." 



The general tenor of Mr. Taylor's Essays however is very good, and 

 his book is a very readable and useful one, especially in all that he has to 

 say on the local geology of those districts in which he has resided. Thus 

 the accounts of the Lancashire coal-field and of the strata in the vicinity 

 of Manchester, are exceedingly interesting, while the illustrations of fossil 

 plants and shells are very appropriately selected. 



Flora of Surrey. By J. A. Brewer. London : Van Voorst. 1863. 



This is a full and comprehensive catalogue of the flowering plants and 

 ferns found in the county, with the localities of the rarer species, from the 

 manuscripts of the late J. D. Salmon, F.L.S., and from other sources, 



