TRUE VOLCANOES. 271 



According to these data the total number of volcanoes in 

 the live American groups is 91, of which 5G belong to the 



and Dr. Weddel (1847), have ascended the summit. In August, 

 1831, Meyen saw large columns of smoke rising ; a year previous- 

 ly the volcano had thrown out scoria?, but never lava streams 

 (Meyen's licise um die Krde, th. ii., s. 33). 



Yolcan de Omato, lat. 16° 50'; it had a violent eruption in the year 



1GG7. 

 Volcan de Uvillas or Uvinas, to the south of Apo ; its last eruptions 



were in the lGth century. 

 Volcan de Pichu-Pichu, 1G miles to the east of the town of Arequipa 



(lat. 16° 25'), not far from the Pass of Cangallo, 9673 feet above 



the sea. 



Volcan Viejo, lat. 16° 55', an enormous crater, with lava streams and 

 much pumice-stone. 



The six volcanoes just mentioned constitute the group of Arequipa. 



Volcan de Tacora or Chipicani, according to Pentland's fine map of 

 the lake of Titicaca, lat. 17° 45', height 19,738 feet. 



Volcan de Sahqma,* 22,354 feet in height, lat. 18° 7'; a truncated 

 cone of the most regular form; see p. 241. The volcano of Sa- 

 hama is (according to Pentland) 927 feet higher than the Chim- 

 borazo, but GG50 feet lower than Mount Everest, in the Himalaya, 

 which is now regarded as the highest peak of Asia. According 

 to the last official report of Colonel Waugh, of the 1 st March, 1 856, 

 the four highest mountains of the Himalayan chain are ; Mount 

 Everest (Gaurischanka), to the northeast of Katmandu, 29,000 feet; 

 the Kuntschinjinga, to the north of Darjiling, 28,154 feet; the 

 Dhaulaqiri (Dhavalagirir), 2G,825 feet; and Tschumalari (Cham- 

 alari), 23,946 feet. 



Volcano of Pomarape, 21,609 feet, lat. 18° 8', almost a twin mount- 

 ain with the following volcano. 



Volcano of Parinacota, 22,029 feet, lat. 18° 12'. 



The group of the four trachytic cones Sahama, Pomarape, Parina- 

 cota, and Gualatieri, lying between the parallels of 18° 7' and 18° 

 25', is, according to Pentland's trigonometric measurement, higher 

 than Chimborazo, or more than 21,422 feet. 



Volcano of Gwlatieri* 21,962 feet, lat. 18° 25', in the Bolivian 

 province Carangas ; very active, according to Pentland (Ilertha, 

 bd. xiii., 1829, s. 21). 



Not far from the Sahama grovp, 18° 7' to 18° 25', the series of vol- 

 canoes and the entire chain of the Andes, which lies to the westward 

 of it, suddenly change their strike, and pass from the direction S.E. 

 — TST.W. into that from north to south, which becomes general as far 

 as the Straits of Magellan. I have treated of this important turning- 

 point, the notch in the shore near Arica (18° 28'), which has an an- 

 alogue on the west coast of Africa, in the Gulf of Biafra, in the first 

 volume of Cosmos, p. 292. 



Volcano of Isl/.ga, lat. 19° 20', in the province of Tarapaca, to the 

 west of Carangas. 



