EL GRAN SECO IN LA PLATA. 41 



in such localities square miles of country may be seen 

 whitened by an incrustation of salt, as if by a fall of 

 snow. Even in their brackish state, these waters are 

 apt to create diarrhoeas, and bowel complaints of 

 various kinds, which are always troublesome, and at 

 times exceedingly injurious to the health of persons 

 obliged to drink them. 



The late Mr. Charles Darwin has given an inter- 

 esting account of his visit to one of these salt districts, 

 near the Rio Negro, which forms the north eastern 

 boundary of Patagonia, and mentions the existence of 

 salt lakes near El Carmen, at the mouth of that river ; 

 where in summer time, when their beds were dry, a 

 floor of salt was exposed, two or three feet thick, 

 remarkable for its purity. The export of this salt in 

 fact formed the main staple of trade from that river. * 

 He also mentions, that at the time of the disastrous 

 droughts which took place in the provinces of Buenos 

 Ayres and Santa Fe, between the years 1827 and 1830, 

 known among the gauchos as "El gran Seco, " "all 

 the small rivers became highly saline, and this caused 

 the deaths of vast numbers of horses, cattle, etc., in 

 particular spots; for when an animal drinks of such 

 water " (he tells us) " it does not recover. * The loss 

 of stock indeed, in the province of Buenos Ayres alone, 

 was reckoned at " a million head " : one unfortunate 

 proprietor at San Pedro, we are told, " had previously 

 to these years, 20,000 head, and at the end not one 

 remained." f 



* See Journal of Researches on Natural History and Geology 

 during the Voyage of H.M.S. Beagle, by Chas. Darwin, edition of 

 1878, pp. 65 6. 



f Ibid., pp. 1334- 



