228 A RAINLESS REGION. 



only a dry coarse grass. In the interior a few beeches and cacti are 

 met with, and then broad swamps, fringed with reeds and rushes. 

 In the spring a mantle of clover spreads over the earth, but only to 

 be withered up by the first heats of summer. 



Along the banks of the Rio Negro the Pampas of Buenos Ayres 

 stretch from the coast of the Atlantic to the foot of the Andes. On 

 a considerable portion of this vast area marshes of salt water encroach 

 a phenomenon all the more curious because the salt lies only on 

 the surface, and all the wells artificially excavated yield fresh water. 

 During the rains the low grounds are flooded ; but as soon as the sun 

 has dried up the plain, it is clothed in rich pasturage, while the 

 elevated table-lands are dry and withered. There, too, the dryness 

 is often attended with disastrous results. From 1827 to 1830, as 

 Mr. Darwin records, not a drop of water fell ; all traces of vegetation 

 disappeared ; the rivers ran dry, and the herds perished in incalculable 

 numbers ; in the single province of Buenos Ayres, the loss was 

 estimated at more than a million head of cattle. 



To the north of -the Rio Salado, at the portals of the Andes, the 

 country assumes a look of implacable desolation ; no winds ever 

 agitate the lower strata of the atmosphere. The water-courses which 

 descend from the mountains lose themselves in the sand ; salt marshes, 

 whence the very birds hold aloof, alone alternate with a soil every- 

 where intersected by crevices. The district of the Pampas which 

 stretches northward to the spurs of the Andes consists of a sandy soil, 

 free from salt, but wholly unproductive. These solitudes, however, 

 are ploughed by running streams, none of which communicate with 

 the sea. They descend from the Andes, traverse the Pampas from 

 east to west, and empty themselves into the saline lakes. Somewhat 

 further to the north, and nearer the Equator, lies an almost unknown 

 region of salt a region of indescribable gloom, where neither tree, nor 

 bush, nor blade of emerald grass, delights the eye. Eighteen months 

 frequently elapse in this land of desolation, worthy of being one of 

 the circles in Dante's " Inferno," without the cheering sound of a 

 shower of rain, and when at length it arrives, it splits the rocks of 



