In regard to export traffic the railways have not attempted to compete with the river anywhere where it is open to maritime navigation; they have merely been concerned to connect with it. On the other hand, the railway and the river are rivals for the home traffic and the traffic of the upper districts which sea-going boats do not reach. Before the time of the railways the river had taken all the goods traffic, but had tolerated on its left bank a post-road between Santa Fe, Corrientes and Asuncion. The railway still has the advantage over the river in regard to speed (in carrying passengers between Rosario and Buenos Aires, and live cattle from the Chaco and the Paraguay for Buenos Aires or the salting works of the lower Uruguay). Even in regard to certain kinds of heavy goods--_quebracho_ timber--the river has not secured a monopoly, and there is a good deal of transport by rail. CHAPTER VIII THE RIVER-ROUTES The use of the river before steam navigation--Floods--The river plain--The bed of the Parana and its changes--The estuary and its shoals--Maritime navigation--The boats on the Parana. The problem of the use of the river-routes of the Parana and the Paraguay is not of interest to Argentina alone. It affects the whole history of colonization in South America. The very name of the Rio de la Plata is a reminiscence of the anxieties of the early navigators who landed there, chiefly in search of a route to the mineral districts of the Andes [Plata = silver]. It is remarkable that the Amazon, which opens a more direct and better route to the Andes, was never used for reaching Peru. It was at the most, and only occasionally, used as a return-route, whereas expeditions to the Cordillera were organized on the banks of the Parana during the whole of the sixteenth century. The routes linking the Parana and the Paraguay with the tableland furrow the whole plain of the Pampa and the Chaco, from the latitude of the estuary to about 16 deg. S. lat. (expedition of Nuflo de Chavez in 1557). An especially close network starts from the river between 18 deg. and 22 deg. S. lat. and ends at Santa Cruz, the most northern centre established by the Spaniards on the plain, at the foot of the Andes, as a consequence of the use of the Parana.[118] [118] There is still a certain amount of goods traffic in this latitude between the river and the Santa Cruz district by the Puerto Suarez and Puerto Pacheco tracks. Spanish colonization, however, did not succeed in making permanent settlements on the Chaco. The Indians, who were masters of it, disputed their passage, and the only practicable route was the southernmost of the roads to the tableland, south of the Rio Salado, which ends at the estuary. From this time onward the prosperity of Buenos Aires eclipsed that of Asuncion. The river ceased to be a great continental route.