^ 



114 THE RIO SAUCE. [chap, 



without a single bush or tree to break the monotono" 

 uniformity. The weather was fine, but the atmosphere 

 remarkably hazy ; I thought the appearance foreboded a 

 gale, but the Gauchos said it was owing to the plain, at 

 some great distance in the interior, being on fire. After 

 a long gallop, having changed horses twice, we reached 

 the Rio Sauce : it is a deep, rapid, little stream, not above 

 twenty-five feet wide. The second posta on the road to 

 Buenos Ayres stands on its banks ; a little above there 

 is a ford for horses, where the water does not reach to 

 the horses' belly ; but from that point, in its course to the 

 sea, it is quite impassable, and hence makes a most useful 

 barrier against the Indians. 



Insignificant as this stream is, the Jesuit Falconer, whose 

 information is generally so very correct, figures it as a 

 considerable river, rising at the foot of the Cordillera. With 

 respect to its source, I do not doubt that this is the case ; 

 for the Gauchos assured me, that in the middle of the dry 

 summer, this stream, at the same time with the Colorado, 

 has periodical floods ; which can only originate in the snow 

 melting on the Andes. It is extremely improbable that a 

 stream so small as the Sauce then was, should traverse 

 the entire width of the continent ; and indeed, if it were 

 the residue of a large river, its waters, as in other ascer- 

 tained cases, would be saline. During the winter we must 

 look to the springs round the Sierra Ventana as the source 

 of its pure and limpid stream. I suspect the plains of 

 Patagonia, like those of Australia, are traversed by many 

 water-courses, which only perform their proper parts at 

 certain periods. Probably this is the case with the water 

 which flows into the head of Port Desire, and likewise 

 with the Rio Chupat, on the banks of which masses of 

 highly cellular scoriae were found by the officers employed 

 in the survey. 



As it was early in the afternoon when we arrived, we 

 took fresh horses, and a soldier for a guide, and started 

 for the Sierra de la Ventana. This mountain is visible 

 from the anchorage at Bahia Blanca ; and Captain Fitz 

 Roy calculates its height to be 3340 feet — an altitude ver}^ 

 remarkable on this eastern side of the continent. I am 

 not aware that any foreigner, previous to my visit, had 

 ascended this mountain ; and indeed very few of the soldiers 

 at Bahia Blanca knew anything about it. Hence we heard 

 of beds of coal, of gold and silver, of caves, and of forests, 



