272 PEOCEEDINGS OP THE GEOLOGICAL SOCIETY. [Feb. 5, 



fesses that this area was once, at some time or another, the sport of 

 forces compared with which the most furious volcanic outbursts of 

 our time are feeble indeed, — even of forces which tossed and crum- 

 pled its strata, like waves of the sea driven before a N.W. wind. 

 But, besides this, he insists upon it that the Highlands have been sub- 

 ject to a force not only much more stupendous than any we now see 

 in operation there (for this I fully admit), but far more stupendous 

 than any of the kind which can be proved to exist, or ever to have 

 existed, in any portion of the world. My objection, therefore, to Mr. 

 Geikie's theory is, that out of several causes of visible change he 

 gives an undue preference to some one or two, ascribing to them effects 

 Avhich they are not proved to be capable of producing, and refusing 

 to other causes of change, which are equally known and visible, 

 effects which are within their easy reach. It is significant of the 

 partial and erroneous view which he takes of the relation between 

 different known causes of change, that when he lays down the abs- 

 tract general principle which we should bear in mind when we are 

 speculating on these subjects, he states that principle in language 

 which is erroneous. " In all such attempts," says Mr. Geikie, 

 speaking of theories opposed to his own, " we make the fatal eiror of 

 forgetting that, in the geological history of our globe, ^ Time is 

 Power.' " Of course, in a loose popular sense, this is true ; but 

 speaking strictly and philosophically, it is altogether incorrect. 

 Time does nothing by itself, nothing except by the aid of its great 

 ally Porce : Eorce working in Time — this is one conception of aU 

 change, or rather of that which produces change. But then due 

 account must be taken of all the kinds of Porce which the records of 

 time reveal. Each special kind of force has its own special effects, 

 and very often these can be produced by none other. We know that 

 Force has been acting always, in all forms and in aU degrees. When 

 we have before us given ascertained mechanical effects, it is indeed 

 a rude philosophy which would ascribe them to any given kind of 

 force, merely on the ground that by this force they could be done in 

 the shortest time. But the philosophy is quite as rude which would 

 select as the cause of those effects some other favourite kind of force, 

 on no other ground whatever than that by this force the operation 

 would consume the longest possible amount of time. It becomes not 

 only rude, but perverse, when the force selected for this preference 

 is one which has never been proved to be capable of producing such 

 effects at all. 'No one appreciates more highly than I do the labours 

 of those older geologists who first taught an earlier generation to 

 estimate more truly the power and efGlciency of certain forces which 

 act very slowly but continuously during long periods of time. The 

 error in scientific speculation against which they fought was the 

 error of laying exclusive or exaggerated stress upon forces of a par- 

 ticular kind — forces the existence of which they did not deny, but 

 which had worked only at comparatively distant intervals, and in 

 alliance always with other forces, the operation of which is ceaseless. 

 It is precisely the same error in principle, though exhibited in a dif- 

 ferent form, which is now exhibited by those geologists who attribute 



