GEAR A. 447 



is very sickly. Yellow-fever is prevalent, and there have 

 been a good many deaths from it recently, though it is 

 said not to have assumed the character of an epidemic 

 as yet. Still more fatal is the malignant dysentery, which 

 has been raging both in town and country for the last 

 two months. 



We are trying to hasten the arrangements for our inland 

 journey, but do not find it very easy. Mr. Agassiz's object 

 in stopping here is to satisfy himself by direct investigation 

 of the former existence of glaciers in the serras of this 

 province, and, if possible, to find some traces of the south- 

 ern lateral moraine, marking the limit of the mass of ice 

 which he supposes to have filled the Amazonian basin in 

 the glacial period. In the Amazonian Yalley itself he has 

 seen that all the geological phenomena are connected with 

 the close of the glacial period, with the melting of the 

 ice and the immense freshets consequent upon its disap- 

 pearance. On leaving the Amazons, the next step in the 

 investigation was to seek the masses of loose materials 

 left by the glacier itself. On arriving here he at once 

 made inquiries to this effect, from a number of persons 

 who have travelled a great deal in the province, and are 

 therefore familiar with its features. The most valuable 

 information he has obtained, valuable from the fact, 

 that the precision with which it is given shows that it 

 may be relied upon, is from Dr. Felice. His occupa- 

 tion as land-surveyor has led him to travel a great deal 

 in the region of the Serra Grande. He has made a valu- 

 able map of this portion of the province, and he tells Mr. 

 Agassiz that there is a wall of loose materials, boulders, 

 stones, &c., running from east to west for a distance of 

 some sixty leagues from the Rio Aracaty-Assu to Bom Jesu, 



