THE LAWS OF GEOLOGICAL ACTION. 9 



very remote, it is true, and perhaps unrecorded in the history 

 of the earth in which the known physical forces may have 

 acted with an intensity much greater than direct observation 

 would lead us to imagine. And this may be believed, alto- 

 gether irrespective of those great secular changes by which hot 

 or cold epochs are produced, and which can hardly be called 

 " catastrophistic," as they are produced gradually, and are 

 liable to recur at definite intervals. 



Admitting, then, that there is a truth at the bottom of the 

 once current doctrines of catastrophism, still it remains certain 

 that the history of the earth has been one of law in all past 

 time, as it is now. Nor need we shrink back affrighted at the 

 vastness of the conception the vaster for its very vagueness 

 that we are thus compelled to form as to the duration of 

 geological time. As we grope our way backward through the 

 dark labyrinth of the ages, epoch succeeds to epoch, and 

 period to period, each looming more gigantic in its outlines 

 and more shadowy in its features, as it rises, dimly revealed, 

 from the mist and vapour of an older and ever-older past. It 

 is useless to add century to century or millennium to millen- 

 nium. When we pass a certain boundary-line, which, after all, 

 is reached very soon, figures cease to convey to our finite 

 faculties any real notion of the periods with which we have 

 to deal. The astronomer can employ material illustrations 

 to give form and substance to our conceptions of celestial 

 space; but such a resource is unavailable to the geologist. 

 The few thousand years of which we have historical evidence 

 sink into absolute insignificance beside the unnumbered aeons 

 which unroll themselves one by one as we penetrate the dim 

 recesses of the past, and decipher with feeble vision the pon- 

 derous volumes in which the record of the earth is written. 

 Vainly does the strained intellect seek to overtake an ever- 

 receding commencement, and toil to gain some adequate grasp 

 of an apparently endless succession. A beginning there must 

 have been, though we can never hope to fix its point. Even 

 speculation droops her wings in the attenuated atmosphere of 

 a past so remote, and the light of imagination is quenched in 

 the darkness of a history so ancient. In time, as in space, the 

 confines of the universe must ever remain concealed from us -, 

 and of the end we know no more than of the beginning. In- 

 conceivable as is to us the lapse of " geological time," it is no 

 more than "a mere moment of the past, a mere infinitesimal 

 portion of eternity." Well may " the human heart, that weeps 

 and trembles," say, with Richter's pilgrim through celestial 

 space, " I will go no farther; for the spirit of man acheth with 



