372 AMAZONIA AND LA PLATA. 



between Tucumau and Salta, and farther down Juraraento, or " Oath," in memory 

 of the solemn vow taken by Bflgrano's army on its march to Peru to achieve the 

 independence of the American natives. 



On issuing from the mountains the Juramento traverses Gran Cbaco first 

 in a southerly direction, and then from north-west to south-east. But here it 

 flows with a scarcely perceptible current, and under the latitude of Tucuman, 

 expands into bcuiadas, half-tlooded morasses and fluvial channels, with uncertain 

 flow and half choked b}' aquatic plants. Beyond Santiago del Estero where 

 the sluggish waters conveige in a single channel, it again spreads out in 

 shnllow basins, which daring the inundations overflow far and wide along both 

 banks. 



At this period the water is fresh ; but during the dry season it becomes slightly 

 saline, so that the lower course takes the name of Rio Salado, " S:dt River." The 

 surveys made by Page with the Water Witch in 1855, and since then by many 

 others, clearlv show that the Juramento is navigible whei'ever it flows in a single 

 continuous stream, and that it would be easy to cut a canal through the bafiadas. 

 Hut the settlers prefer forwarding their produce by the railway crossing the plain 

 from Rosario direcitlv to Tucuman. 



Thi<: Rio Duixe. — Mar Chiquita. 



With one exceptional! the pampas rivers south of the Rio Juramento fail to 

 reach the Parana, although the direction of their valleys shows that they belong 

 to that basin, and were, in fact, formerly perennial affluents of that watercourse. 

 Such is the Rio Dulce, which flows from the Salta uplands in a southerly direction, 

 and after receiving on its right bank numerous torrents from the Sierra d'Acon- 

 quija, describes a great hend south-eastwiirds round the Sierra de Guazayan, 

 parallel with the Juramento. But north of the northern spurs of the Cordoba 

 >.Iountains the Rio Dulce, already brackish, despite its name, begins to ramify and 

 wander aimlessly over the almost uninhabited plains, where at least six channels 

 have been traced, which are still flooded during the inundations. Before 1825, 

 the eastern or main branch watered the plantations of Loreto, Atamisqui, and 

 Salavina ; but it was deflected by some obstruction westwards to the chain of 

 Saladillo lagoons, which are so saturated with salt that the water is as buoyant as 

 that of the Dead Sea, or of Lake TJrmiah. 



There can be no doubt that the vast saline depressions stretching south-west- 

 wards between the Sierras de Cordoba and de los Llanos formerly jeceived the 

 waters of the Rio Dulce ; but at present the Saladillo is rejected eastwards to the 

 channel occupied before 1825, beyond which it gradually runs out in the Porongos 

 marsh or lagoon. This basin terminates southwards in a real lake, the Mar 

 Chiquita, " Little Sea," which shifts its contour lines according to the quantity of 

 water discharged by its affluent. Its bed, formed of a hard clay, is flooded in 

 some places to a depth of 110 feet. 



