LAKES AND EIVERS OF PATAGONIA. 385 



The Chubut and SexXguer Rivers. 



A mucli smaller volume is sent down by the Chubut, a river whose very exis- 

 tence was still unknown in 1833, unless it is to be identified with the Rio 

 Camerones of the old maps. Its farthest headwaters descend from the Cordillera 

 south of Nahuel-Huapi, and once formed, the river flows without many windings 

 through an "accursed land" of rocks and shingle, where afiluents are rare on the 

 south, and altogether absent on the north side. 



The Senguer (Singerr, Senguel), chief tributary of the Chubut, rises on the 

 Andes near the sources of the Aysen, and, according to a native report mentioned 

 by Moreno, the Senguer (Chubut) forms with the Aysen a continuous waterway 

 across the Continent from the Atlantic to the Pacific. It first traverses a sjalendid 

 region of pastures and woodlands, a veritable Patagonian oasis ; then, being 

 deflected to the north-east by a barrier of rocks and other obstacles, its turbid 

 current expands in a vast shallow basin Avhich rises and falls with the seasons, 

 and which, according to Fontana, stands about 1,000 feet above sea-level. 



This basin, composed of the lakes Colhué and Musters, which are almost com- 

 pletely separated by a meridional chain of volcanic crests, is fringed on the south 

 side by marshy tracts flooded by its overflow. Bej^ond this morass, where it 

 loses a third of its volume, the Senger continues its course to the Chubut, 

 without, however, contributing sufiicient to make it navigable at all times. Boats 

 can ascend with the flow, but they find only five or six feet of water in its bed 

 except during the melting of the snows. 



The Rio Deseado. 



The Rio Deseado, " Desire," discovered by Cavendish in 1586, falls into the 

 estuary of the same name south of the Gulf of St. George. It is even less copious 

 than the Chubut, although it also traverses nearly the whole breadth of the 

 Patagonian peninsula. Lake Buenos Ayres, which probably at one time fed the 

 Deseado, has no longer any outlet, and now sleeps in its circular basin like a 

 flooded crater. 



In these Patagonian regions, which were formerly far more humid than at 

 present, travellers have observed several other basins, which are now dry, but 

 which were at one time filled with Avater, as is evident from the alluvial deposits 

 on their beds. 



At its mouth the Deseado is usually a mere rivulet, with a volume reduced at 

 times to a few cubic feet per second, but after the rains it is swollen to tbe 

 proportions of a considerable river It reaches the coast at the head of an 

 elongated inlet of cxtremel}' picturesque aspect, which extends for a distance of 

 some 24 miles in the direction from west to east. The coast line is greatly 

 diversified with numerous islands and islets, reefs and headhinds, bays, ravines, 

 and glens. All the eminences are extinct volcanoes, which were probably still 



