THE VOYAGE OF THE BEAGLE 



89 



obliged to bivouac on the plain. In the morning we had 

 caught an armadillo, which,, although a most excellent dish 

 when roasted in its shell, did not make a very substantial 

 breakfast and dinner for two hungry men. The ground at 

 the place where we stopped for the night, was incrusted with 

 a layer of sulphate of soda, and hence, of course, was with- 

 out water. Yet many of the smaller rodents managed to 

 exist even here, and the tucutuco was making its odd little 

 grunt beneath my head, during half the night. Our horses 

 were very poor ones, and in the morning they were soon 

 exhausted from not having had anything to drink, so that 

 we were obliged to walk. About noon the dogs killed a kid, 

 which we roasted. I ate some of it, but it made me intoler- 

 ably thirsty. This was the more distressing as the road, 

 from some recent rain, was full of little puddles of clear 

 water, yet not a drop was drinkable. I had scarcely been 

 twenty hours without water, and only part of the time under 

 a hot sun, yet the thirst rendered me very weak. How people 

 survive two or three days under such circumstances, I cannot 

 imagine : at the same time, I must confess that my guide did 

 not suffer at all, and was astonished that one day's depriva- 

 tion should be so troublesome to me. 



I have several times alluded to the surface of the ground 

 being incrusted with salt. This phenomenon is quite differ- 

 ent from that of the salinas, and more extraordinary. In 

 many parts of South America, wherever the climate is mod- 

 erately dry, these incrustations occur; but I have nowhere 

 seen them so abundant as near Bahia Blanca. The salt here, 

 and in other parts of Patagonia, consists chiefly of sulphate' 

 of soda with some common salt. As long as the ground 

 remains moist in the salitrales (as the Spaniards improperly 

 'call them, mistaking this substance for saltpetre), nothing is 

 to be seen but an extensive plain composed of a black, muddy 

 soil, supporting scattered tufts of succulent plants. On return- 

 ing through one of these tracts, after a week's hot weather, 

 one is surprised to see square miles of the plain white, as if 

 from a slight fall of snow, here and there heaped up by the 

 wind into little drifts. This latter appearance is chiefly 

 caused by the salts being drawn up, during the slow evapora- 

 tion of the moisture, round blades of dead grass, stumps of 



