PASSAGES. 



53 



titles. As far as my inquiries went, I satisfied myself that when met 

 with on the edge of soundings it will be found to interrupt the navi- 

 gation more seriously to the eastward than along the coast. 



Our run towards the Rio Negro was attended with fine weather, 

 and after reaching the parallel on which the Ariel Rocks were be- 

 lieved to exist, and to the eastward of the longitude, we sailed two 

 degrees to the west, but saw nothing of them ; and from our search 

 and that of others we feel satisfied that they have no existence. The 

 position in which they were supposed to lie was in latitude 40° south, 

 longitude 57° 33' west. 



As We approached the coast, we found the soundings extremely 

 regular, varying about a fathom for every three miles. The coast 

 at the mouth of the Rio Negro presents a low line of sand-hills. To 

 the south of the river is a bluff 100 feet in height, of tertiary lime- 

 stone, regularly stratified ; to the north of Point de Maine, there is a 

 remarkable sand-hill, called the Barrancas ; and beyond are seen 

 others, which terminate in extensive pampas. 



We dropped anchor off the Rio Negro on the eighteenth day from 

 Rio de Janeiro. 



The Rio Negro is barred, and from the examinations we made and 

 the reports of the pilots, it proved to be a shifting bar. In endeavor- 

 ing to enter the former channel, without pilots, with the tenders, we 

 grounded on the sand-bar that had recently formed, rendering it no 

 longer practicable for the entrance of vessels. A vessel drawing more 

 than 10 feet water cannot safely enter the Rio Negro. The best 

 position to anchor in the roadstead is with the flag-staff on Point de 

 Maine north 65° west, in about 9 or 10 fathoms water, within a mile 

 and a half of the breakers, which extend in a northeast and southwest 

 direction. 



Pilots are usually found here, but in case they should not come off 

 immediately, it is better to wait for them than to attempt to follow 

 the directions for entering, which, from the shifting of the sands, are 

 not to be relied upon after a flood or freshet. At the time of our visit, 

 two poles were placed on Point de Maine, one on the hill and another 

 near the beach; the first had several pieces nailed across it, that 

 served for the purpose of ascending, for a look-out ; these poles, kept 

 in range, were intended as guides to lead a vessel in the deepest water 

 over the bar, and until within half a cable's length of the point, which 

 must then be turned short round to pass into the river. The course 



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