1834.] TRACES OF INDIANS. 13$ 



surface of its body on the atmosphere may counter-balance its gravity. 

 The force to keep up the momentum of a body moving in a horizontal 

 plane in the air (in which there is so little friction) cannot be great, and 

 this force is all that is wanted. The movement of the neck and body 

 of the condor, we must suppose, is sufficient for this. However this 

 may be, it is truly wonderful and beautiful to see so great a bird, hour 

 after hour, without any apparent exertion, wheeling and gliding over 

 mountain and river. 



April 2gtk. From some high land we hailed with joy the white 

 summits of the Cordillera, as they were seen occasionally peeping 

 through their dusky envelope of clonds. During the few succeeding 

 days we continued to get on slowly, for we found the river-course very 

 tortuous, and strewed with immense fragments of various ancient slaty 

 rocks, and of granite. The plain bordering the valley had here attained 

 an elevation of about eleven hundred feet above the river, and its character 

 was much altered. The well-rounded pebbles of porphyry were mingled 

 with many immense angular fragments of basalt and of primary rocks. 

 The first of these erratic boulders which I noticed was sixty-seven 

 miles distant from the nearest mountain ; another which I measured 

 was five yards square, and projected five feet above the gravel. Its 

 edges were so angular, and its size so great, that I at first mistook it 

 for a rock in situ, and took out my compass to observe the direction 

 of its cleavage. The plain here was not quite so level as that nearer 

 the coast, but yet it betrayed no signs of any great violence. Under 

 these circumstances it is, I believe, quite impossible to explain the 

 transportal of these gigantic masses of rock so many miles from their 

 parent-source, on any theory except by that of floating icebergs. 



During the two last days we met with signs of horses, and with 

 several small articles which had belonged to the Indians such as 

 parts of a mantle and a bunch of ostrich feathers but they appeared 

 to have been lying long on the ground. Between the place where the 

 Indians had so lately crossed the river and this neighbourhood, though 

 so many miles apart, the country appears to be quite unfrequented. 

 At first, considering the abundance of the guanacos, I was surprised 

 at this ; but it is explained by the stony nature of the plains, which 

 would soon disable an unshod horse from taking part in the chase. 

 Nevertheless, in two places in this very central region, I found small 

 heaps of stones, which I do not think could have been accidentally 

 thrown together. They were placed on points, projecting over the 

 edge of the highest lava cliff, and they resembled, but on a small scale, 

 those near Port Desire. 



May tfh. Captain Fitz Roy determined to take the boats no higher. 

 The river had a winding course, and was very rapid ; and the appear- 

 ance of the country offered no temptation to proceed any further. 

 Everywhere we met with the same productions and the same dreary 

 landscape. We were now one hundred and forty miles distant from 

 the Atlantic, and about sixty from the nearest arm of the Pacific. The 

 valley in this upper part expanded into a wide basin, bounded on the 



