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SCIENGK 



[N. S. Vol. XII. No. 307. 



ern physics. From Steno onward the spirit 

 of geology was catastrophic; from Hutton 

 onward it grew increasingly uniformitarian ; 

 from the time of Darwin and Kelvin it has 

 become evolutional. The ambiguity of the 

 word ' uniformitarian ' has led to a good 

 deal of fruitless logomachy, against which 

 it may be as well at once to guard by indi- 

 cating the sense in which it is used here. 

 In one way we are all uniformitarians, i. e., 

 we accept the doctrine of the ' uniform ac- 

 tion of natural causes/ but, as applied to 

 geology, uniformity means more than this. 

 Defined in the briefest fashion it is the 

 geology of Lyell. Hutton had given ns a 

 ' Theory of the Earth,' in its main outlines 

 still faithful and true; and this Lyell spent 

 his life in illustrating and advocating; but 

 as so commonly happens the zeal of the 

 disciple outran the wisdom of the master, 

 and mere opinions were insisted on as 

 necessary dogma. What did it matter if 

 Hutton as a result of his inquiries into ter- 

 restrial history had declared that he found 

 no vestige of a beginning, no prospect of 

 an end? It would have been marvellous 

 if he had ! Consider that when Hutton's 

 ' Theory ' was published William Smith's 

 famous discovery had not been made, and 

 that nothing was then known of the orderly 

 succession of forms of life, which it is one 

 of the triumphs of geology to have revealed; 

 consider, too, the existing state of physics 

 at the time, and that the modern theories 

 of energy had still to be formulated ; con- 

 sider also that spectroscopy had not yet 

 lent its aid to astronomy and the consequent 

 ignorance of the nature of nebulae; and 

 then, if you will, cast a stone at Hutton. 

 With Lyell, however, the case was differ- 

 ent: in pressing his uniformitarian creed 

 upon geology he omitted to take into ac- 

 count the great advances made by its sister 

 sciences, although he had knowledge of 

 them, and thus sinned against the light. 

 In the last edition of the famous ' Princi- 



ples ' we read : " It is a favorite dogma of 

 some physicists that not only the earth, but 

 the sun itself, is continually losing a por- 

 tion of its heat, and that as there is no 

 known source by which it can be restored 

 we can foresee the time when all life will 

 cease to exist on this planet, and on the 

 other hand we can look back to a period 

 when the heat was so intense as to be in- 

 compatible with the existence of any or- 

 ganic beings such as are known to us in the 

 living or fossil world. * * * A geologist 

 in search of some renovating power by 

 which the amount of heat may be made to 

 continue unimpaired for millions of years, 

 past and future, in the solid parts of the 

 earth * * * has been compared by an 

 eminent physicist to one who dreams he 

 can discover a source of perpetual motion 

 and invent a clock with a self-winding ap- 

 paratus. But ivhy should ive despair of detect- 

 ing proofs of such generating and self-sustaining 

 power in the works of a Divine Artificer f ' ' Here 

 we catch the true spirit of uniformity ; it 

 admittedly regards the universe as a self- 

 winding clock, and barely conceals a con- 

 viction that the clock was warranted to 

 keep true Greenwich time. The law of the 

 dissipation of energy is not a dogma, but a 

 doctrine drawn from observation, while the 

 uniformity of Lyell is in no sense an induc- 

 tion ; it is a dogma in the narrowest sense 

 of the word, unproved, incapable of proof, 

 hence pei'haps its power upon the human 

 mind; hence also the transitoriness of that 

 power. Again, it is only by restricting its 

 inquiries to the stratified rocks of our planet 

 that the dogma of uniformity can be main- 

 tained with any pretence of argument. 

 Directly we begin to search the heavens the 

 possibility, nay even the likelihood, of the 

 nebular origin of our system, with all that 

 it involves, is borne in upon us. Lyell 

 therefore consistently refused to extend his 

 gaze beyond the rocks beneath his feet, and 

 was thus lead to do a serious injury to our 



