150 PATAGONIA AND SHEEP-REARING 



had hollowed it.^ The Argentine village dates from 

 1890. At first it lived by supplying fodder to the 

 convoys of wagons which carried the wool. The 

 railway has suppressed this traffic, and the only outlet 

 of the oasis to-day is the small port of San Antonio, 

 where the wool is shipped, and where the district is 

 unsuitable for any kind of cultivation. 



Like the coast region, the Valcheta district seems 

 marked out by its moderate altitude to serve as winter 

 pasture. In point of fact, it is used during the whole 

 year. The springs do not dry up in summer. The 

 streams which flow from the south toward the Bajo 

 de Valcheta are permanent. In addition, a few wells 

 have been bored in the Tertiary strata. Contrary to 

 experience on the coast, therefore, cattle can be kept 

 here during the summer. There is less chance for 

 the grasses to reproduce, and the pasture tends to 

 become impoverished. 



The third zone, 130 miles from the coast, is that of 

 the tableland of the Cerros Colorados, where low 

 masses of red granite rise like an archipelago amongst 

 the Tertiary formations deposited in the intervening 

 depressions. In the west its altitude rises from 650 to 

 1,300 feet. It is one of the poorest parts of the table- 

 land, and the size of the flock is reduced to 600 head 

 to the square league. The naked rock crops up, not 

 covered, as it is further east, by a bed of gravel. In 

 the valleys there is little water, and it lies very deep. 

 There are no periodical removals of the animals. 

 Winter and summer they remain within range of a 

 few poor springs, which are caused by various outcrops 

 of lava of limited extent ; and they leave these, and 

 wander over the tableland, only in the rainy season. 

 Beyond the Cerros Colorados the line rises rapidly, 

 and at Maquinchao it reaches the basin of Lake Carilauf- 



• Pedro Ezcurra, " Camino indio entre los rios Negro y Chubut : 

 la travesia de Valcheta," BoL Instil. Geog Argent., xix. 1898, pp. 

 134-38. 



