224 CLASSICS OF MODERN SCIENCE 

 ing the enigmas presented to him in the earth's structure — instead of 

 being prompted to undertake laborious inquiries into the natural 

 history of the organic world, and the complicated effects of the igneous 

 and aqueous causes now in operation — was taught to despond from 

 the first. Geology, it was affirmed, could never rise to the rank of 

 an exact science ; the greater number of phenomena must forever re- 

 main inexplicable, or only be partially elucidated by ingenious conjec- 

 tures. Even the mystery which invested the subject was said to 

 constitute one of its principal charms, affording, as it did, full scope 

 to the fancy to indulge in a boundless field of speculation. 



The course directly opposed to this method of philosophizing con- 

 sists in an earnest and patient inquiry, how far geological appearances 

 are reconcilable with the effect of changes now in progress, or which 

 may be in progress in regions inaccessible to us, but of which the 

 reality is attested by volcanoes and subterranean movements. It also 

 endeavours to estimate the aggregate result of ordinary operations 

 multiplied by time, and cherishes a sanguine hope that the resources 

 to be derived from observation and experiment, or from the study of 

 Nature such as she now is, are very far from being exhausted. For 

 this reason all theories are rejected which involve the assumption of 

 sudden and violent catastrophes and revolutions of the whole earth, 

 and its inhabitants — theories which are restrained by no reference 

 to existing analogies, and in which a desire is manifested to cut, 

 rather than patiently to untie, the Gordian knot. 



We have now, at least, the advantage of knowing, from experi- 

 ence, that an opposite method has always put geologists on the road 

 that leads to truth — suggesting views which, although imperfect at 

 first, have been found capable of improvement, until at last adopted 

 by universal consent; while the method of speculating on a former 

 distinct state of things and causes has led invariably to a multitude of 

 contradictory systems, which have been overthrown one after the 

 other — have been found incapable of modification — and which have 

 often required to be precisely reversed. 



The remainder of this work will be devoted to an investigation of 

 the changes now going on in the crust of the earth and its inhabitants. 

 The importance which the student will attach to such researches will 

 mainly depend on the degree of confidence which he feels in the prin- 

 ciples above expounded. If he firmly believes in the resemblance or 



