1836.] BAHIA, LPiAZIL. 495 



From tlie absence of all carbonaceous matter, Professor Ehren- 

 berg- believes that these organic bodies have passed through the 

 volcanic fire, and have been erupted in the state in which Me 

 now see them. The appearance of the layers induced me to 

 believe that they had been deposited under water, though from 

 the extreme dryness of the climate I was forced to imagine, that 

 torrents of rain had probably fallen during- some great eruption, 

 and that thus a temporaiy laive had been formed, into which the 

 ashes fell. But it may now be suspected that the lake was not a 

 temporary one. Anyhow, we may feel sure, that at some former 

 epoch, the climate and productions of Ascension were very dif- 

 ferent from what they now are. AYhere on the face of the earth 

 can we find a spot, on Avhich close investigation will not discover 

 signs of that endless cycle of change, to which this earth has 

 been, is, and will be subjected ? 



On leaving" Ascension we sailed for Bahia, on the coast of 

 Brazil, in order to complete the chronometrical measurement of 

 the world. "We arrived there on August 1st, and stayed four 

 days, during- which I took several long walks. I was glad to 

 find my enjoyment in tropical scenery had not decreased from the 

 want of novelty, even in the slightest degree. The elements of 

 the scenery are so simple, that they are worth mentioning, as a 

 proof on what trifling circumstances exquisite natural beauty 

 depends. 



The country may be described as a level plain of about three 

 hundred feet in elevation, which in all parts has been worn into 

 flat-bottomed valleys. This structure is remarkable in a granitic 

 land, but is nearly universal in all those softer formations of 

 wliich plains are usually composed. The whole surface is covered 

 by various kinds of stately trees, interspersed with patches of 

 cultivated ground, out of which houses, convents, and chapels 

 arise. It must be remembered that within the tropics, the wild 

 luxuriance of nature is not lost even in the vicinity of large 

 cities ; for the natural vegetation of the hedges and hill-s-ides 

 overpowers in picturesque effect the artificial labour of man. 

 Hence, there are only a few spots where the bright red soil 

 affords a strong- contrast with the universal clothing of green. 

 From the edges of the plain there are distant views either of 

 the ocean, or of the great Bay ^ith its low-wooded shorts, and 



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