212 ROADS AND RAILWAYS 



have had to be partially reconstructed, and raised 

 higher, after a series of rainy years. ^ 



The colonization of that part of the plain which 

 actually constitutes the province of Buenos Aires 

 was late. It belongs to the era of the railways. There 

 is only one historic road crossing this area, which 

 remained until the last third of the nineteenth 

 century in the hands of the Indian tribes. This is 

 the salt road. We do not know exactly when it began 

 to be used. In the eighteenth century, in spite of 

 the competition of salt from Cadiz and Patagonia, 

 imported by sea, the Pampa salt was the main part 

 of the supply of Buenos Aires. The salt road was 

 not abandoned until after 1810. We still have the 

 diary of several journeys from Buenos Aires to the 

 salt-pits. They were military expeditions. Hundreds 

 of wagons, with a strong escort, collected at Lujan 

 and Chivilcoy, and they reached Atreuco, west of 

 the Guamini and Carbue lakes, after a fifteen to 

 twenty-five days' march. 



The itinerary was fixed in detail. In 1796 D'Azara 

 noticed the wells sunk by the salters, north of the 

 Palentelen lagoon (Bragado), when they found the 

 lagoon dry. From Palentelen south-westward the salt 

 road followed the track used by the Indians of the 

 south-west in their expeditions against the ranches 

 of the Buenos Aires frontier. Near Lake Epecuen, 

 north of Carbue, it was joined by another track which 

 came from Olavarria, the stages of which were marked 

 by the streams that came from the Sierra de Curu- 

 malan. The Carbue district, the cross-roads of the 



" Certain duplications in the actual scheme of the railways are 

 due to this need to correct a line that had been planned hastily and 

 was useless. The line from Justo Daract to La Paz (1912), on the 

 Pacific railway, avoids the steep inclinations of the first line, which 

 followed the course of the wagon-road via San Luis. The inter- 

 pretation of the relief is particularly difficult in a country which has 

 not been shaped by normal erosion. Blunders detected by later 

 topographical inquiries were similarly committed in constructing the 

 Patagonian railways. 



