LAKES AND EIVERS OP PATAGONIA. 383 



far more extensive than tliat o£ the Colorado. All the running waters of the 

 eastern slopes of the Andes between 36° and 41° south latitude are collected by 

 the Neuquen and the Liraay, its two main headstreams which enclose a vast 

 triangular space about the foothills and the pampas. 



The Neuquen, which rises near the Chilian volcano in the little lake Malbarco, 

 7,000 feet above sea level, is joined by numerous torrents before plunging into a 

 wild gorge in the range of foothills below Piedra Lisa. It follows the eastern 

 base of this range as far as its confluence with its largest tributary, the Rio 

 Agrio, which issues from a longitudinal valley between two parallel Cordilleras. 

 A short distance below the confluence nearly all the mountain tracks from the 

 passes between Mounts Antuco and Quetrupillan, converge at the Paso de- los 

 Indios, that is, the chief ford, now guarded by a fort. Below this point the 

 Neuquen sweeps round the plateau to its junction with the Liruay ; but in this 

 part of its course it is joined by no other affluents. 



The Rio Limay. — Lake Nahuel-Huapi. 



The Liraay, second main headstream of the Rio Negro, is formed by the 

 confluence of numerous torrents which descend from the Argentino-Chihan, 

 water-parting in a space of about 185 miles north and south. Several lakes 

 flooding old glacial valleys send their overflow to the impetuous Limay, which 

 itself escapes from the famous Lake Nahuel-Huapi, " Tiger Island," so named 

 from a long sedgy island occupying the centre of the basin. 



Nahuel-Huapi, which occupies a depression of "great importance on the line of 

 a future trans continental highway between Bahia Blanca and Yaldivia, has been 

 known for over two centuries. Here the Jesuit missionaries had already estab- 

 lished themselves in the midst of the Araucanian Indians so early as 1670, and at 

 the beginning of the eighteenth century they founded a settlement near the head 

 of the Rio Limay. But this station was destroyed by an incursion of hostile 

 natives, and although it was again visited by other missionaries, Nahuel-Huapi 

 was not S3'stematically explored till the year 1855. 



Since that time numerous travellers have found their way to the shores of this 

 lovely lake, and about 1878 it was formally occupied by the Argentine Govern- 

 ment. Nevertheless, its contour lines are not yet accurately determined, and its 

 form is differently represented by different observers. According to Siemiradzki 

 this Alpine sea is much smaller than is usually supposed, being only 28 instead of 

 Ô0 miles long, as stated by previous travellers, with an extreme breadth of not 

 more than 9 or 10 miles. 



But whatever be its size, all are unanimous in praise of this beautiful lake, in 

 whose crystal waters are mirrored the surrounding heights, in one place bare 

 trachyte cliffs, in another steep granite escarpments clothed with beech and pine 

 groves, and dominated in the background by snow}^ pyramids. Its altitude above 

 the sea is variously estimated at from 1,760 to over 2,000 feet. 



Immediately after issuing from Nahuel-Huapi, the Limay trends round 



