398 A JOURNEY IN BRAZIL. 



of a separate chapter. The reader will find occasional 

 repetitions of facts already stated in the earlier part of 

 the narrative ; but they are retained for the sake of giv 

 ing a complete and consistent review of the subject at 

 this point of our journey, where it became possible to 

 compare the geological structure of the Amazonian Val 

 ley with that of the southern provinces of Brazil and of 

 those bordering on the Atlantic coast. 



THE existence of a glacial_rjeripd, however much derided 

 when first announced, is now a recognized fact. The 

 divergence of opinion respecting it is limited to a ques 

 tion of extent ; and after my recent journey in the Ama 

 zons, I am led. to add a new chapter to the strange history 

 of glacial phenomena, taken from the southern hemisphere, 

 and even from the tropics themselves. 



I am prepared to find that the statement of this new 

 phase of the glacial period will awaken among my scien 

 tific colleagues an opposition even more violent than 

 that -by which the first announcement of my views on 

 this subject was met. I am, however, willing to bide my 

 time ; feeling sure that, as the theory of the ancient ex 

 tension of glaciers in Europe has gradually come to be 

 accepted by geologists, so will the existence of like phe 

 nomena, both in North and South America, during the 

 same epoch, be recognized sooner or later as part of a 

 great series of physical events extending over the whole 

 globe. Indeed, when the ice-period is fully understood, 

 it will be seen that the absurdity lies in supposing that 

 climatic conditions so different could be limited to a small 

 portion of the world s surface. If the geological winter 



