104 RIO NEGRO. 



The current is mostly downward, although the tide is felt about ten 

 miles above its mouth. The ebb sets off shore some three or four 

 miles, and may be known by the discoloration of the water, which 

 just without the bar is comparatively fresh. The depth at high water 

 on the bar is two and a half fathoms, and the bar is a changing one. 



No springs were observed in the vicinity, or any trace of running 

 water, except in the river. The water from the rains collects in the 

 depressions, and forms large ponds, covering acres of ground, but only 

 a few inches in depth. 



The time of our visit corresponded in season to our midsummer 

 months, and the mean temperature was found to be 73°. The winters 

 are represented as very mild ; snow does fall, but it disappears in a 

 few hours. Ice is seldom seen, though frosts appear to be frequent in 

 the winter. January, February, March, and April, are the least tem- 

 pestuous months. 



The vegetation of the upland bears the marks of long-continued 

 droughts, in an absence of trees, and the roots of plants penetrating 

 vertically. The stunted appearance of the shrubs, branching from 

 their base, their branches dense, rigid, and impenetrable, usually 

 growing into spines ; the smallness of the leaves, and their texture 

 which is dry, coriaceous, and hardly deciduous ; together with the 

 general brown aspect of the landscape, all denote a vegetation adapted 

 to endure or escape drought. 



There was formerly some trade here with Boston and New York, in 

 hides, horns, bones, and tallow, in exchange for cotton and woollen 

 goods of a warm fabric, hardware, crockery, boots and shoes, a few 

 articles of furniture, spirits, and tobacco, all of which are bartered at 

 an enormous profit. Considerable quantities of salt are shipped round to 

 Buenos Ayres. Vessels discharging or taking in a cargo here, pay 

 twelve and a half cents per ton. Vessels stopping without discharging 

 pay half duty ; vessels for refreshments are permitted to remain twenty- 

 five days free of duty, after that time they pay half duty. This duty 

 includes pilotage and all other charges ; but the governor seems to have 

 the power to exact the full duty whenever he thinks proper. 



Sarsaparilla abounds in this section of the country. 



As the bar is a shifting one, no permanent directions can be given, 

 nor can any survey be relied on. The annual freshets and gales of 

 wind that take place from May to October, often change the position 

 of the bar. According to the pilots, it had recently undergone a 

 change, and the depth of water was three feet less on it than had been 

 before. Even the direction had been altered from southeast-by-south, 

 to southeast, by compass. 



