416 SOUTH AMERICA— THE ANDES EEGIONS. 



the name of Portezuelo San José, from the extinct San Jose volcano (20,020 feet),, 

 rising to the south, with an enormous breached crater facing west. In 1843 an 

 earthquake overthrew one of the neighbouring heights, filling the valley with a 

 chaos of rocks for a space of "over three leagues." 



Maipo (17,670 feet) seems, like San José, to be extinct, nor is there any record 

 or tradition of its disturbances. The crater, two miles round and filled with snow, 

 inclines eastwards at a height of 6,560 feet above Lake Diamante, one of the chief 

 sources of the Argentine river of like name. From the summit, scaled by 

 Glissfeldt in 1883, the gaze sweeps over a range of heights, grayish on the Chilian, 

 black on the Argentine side, flecked with snow and scored by short glaciers. 



OVERO — TiNGUIRAIRICA. 



Eastwards a cordillera disposed parallel with the dividing line of crests, but 

 4,900 feet lower, stretches north and south in Argentine territory. At the 

 southern foot of the cone the frontier is crossed by the Maipo Pass (11,400 feet) 

 at a scarcely perceptible incline, whereas farther south the more elevated Atravesio 

 de la Lena Pass, as it is called by Glissfeldt, forms a narrow ridge with steep 

 approaches on both sides. From this gap a view is commanded of the Overo 

 volcano (15,550 feet), in Argentine territory, a mass of black lavas and grey ashes, 

 with a glacier descending obliquely down its flanks. 



In these regions the snowfields present peculiar forms known by the name of 

 nieve pcnifente, " penitent snow," so called from the eccentric resemblance to 

 cowled " friars penitent " aflected by the frozen masses under the action of sun 

 and wind. The crystalline parts, which resist evaporation and the melting 

 process, ramify in the strangest fashion, in many places leaving the black 

 ground exposed between the fantastic blocks of ice which sometimes stand five or 

 six feet high. 



Under the same latitude as the Overo volcano, but far within the Chilian 

 frontier, Glissfeldt discovered a wonderful glacier descending in a lateral valley 

 parallel with the main range down to the zone of cultivated land and human 

 habitations. In 1882 the Los Cipreses torrent, to which it gives rise between the 

 Agua de la Vida and Agua de la Muerte sources, had its head at the level of 

 6,260 feet, and the natives show a block 5,840 feet high, which thirty years 

 previously was reached by the front of the glacier. 



Beyond Tinguirairica (14,700 feet), which has been quiescent throughout the 

 historic period, the main cordillera is continued southwards by Las Damas and 

 by Peteroa (11,925 feet), which is said to have ejected lavas or ashes in 1762, and 

 again in 1837. The Las Damas Pass has received its name from the astronomer 

 Souillac, who visited these districts in 1805^ and reported that the mountain 

 might be quite easily crossed even by " ladies " The Planch on Pass stands at 

 an elevation of 9,915 feet on the flanks of Peteroa, and was frequently followed 

 by the marauding Indians, who formerly carried off the cattle of the Argentine 

 farmers and sold them on the Chilian markets. Many engineers have proposed 



