LECTURE XI. 



30^ 



troyed every living being, a new creation took place with more 

 perfect forms, according to a premeditated plan by the inter- 

 ference of a personal creator. I confess that the simpHcity, 

 clearness, and, so to speak, mathematical precision with which 

 this theory was propounded by the highest authorities greatly 

 captivated me in my younger years — excepting, perhaps, the 

 idea of the interference of a personal creator, which I found at 

 all times difficult to reconcile with the laws of sound reasoning. 

 If this creator, as EoUe alleges, is the keystone of the whole 

 system, my disbelief in his interference has probably contri- 

 buted to my speedy rejection of the whole theory. A con- 

 tinued examination of these questions from every point of 

 view, and a thorough investigation of the facts upon which any 

 part of the theory rests, led me and the majority of my contem- 

 poraries to the conviction that there were no such independent 

 periods in the history of the earth, but only a gradual develop- 

 ment. Here and there, temporary and local convulsions may 

 have occurred, but these were confined to comparatively small 

 regions of the surface of the earth, and nowise extending their 

 destructive effects over the whole globe. The various species 

 of living beings, plants, and animals, did not become extinct at 

 once, hke fire at the approach of the Fohn (a moist south wind 

 on the lakes of Switzerland), and rekindled after its passage. 

 Species are constantly disappearing from the list of living 

 beings ; but new ones arise, and the aspect of the remains of 

 extinct life in the strata changes as gradually as that of the 

 species at the present time. Instead of sudden revolutions, I, 

 on the contrary, merely behold infinitely long periods of time, 

 during -svTiich the effects of apparently small forces, acting in 

 the smallest visible proportions, gradually accumulate until, sud- 

 denly as it were, they reveal their might. It would lead us 

 too far to enter upon this subject more fully ; but I felt bound 

 to touch upon it, to prevent misapprehension of what follows. 



The end of the tertiary period, which we do not separate 

 from the present by a sharply defined hne, but by a broad trans- 

 itional margin, was, doubtless, distinguished by a somewhat 

 warmer climate, from that which at present obtains in central 

 Europe, and which is, by the way, rather exceptional when com- 



