Ascent of Cotopaxi. 579 



Wliile standing on the rim of the crater, holding to his 

 Indian servant with one hand, and with the other examin- 

 ing the deposits of a fumarole, a gust of air filled both 

 eyes with sand impregnated with sulphuric acid, causing 

 violent inflammation. This put an end to observation, 

 and made it the part of wisdom to descend as soon as pos- 

 sible. He left the crater at 1.45 p.m., and reached his en- 

 campment at the head of the ridge in three hours and a 

 half, just as a heavy snow-storm began. 



" If the scientific results of ray ascent," says M. Reiss, 

 " do not meet the expectation of savans, I console myself 

 with the reflection that I have pointed out the road, and 

 that other travelers may make the ascent without being 

 hindered by the general notion that it is impossible to 

 reach the crater." He says it is possible to ascend from 

 the snow-limit to the summit in four or five hours. But 

 as the ascent is steep and laborious, it is better to sleep the 

 first night at the limit, and the second night on the arenal, 

 the sand of which is warm. This will give a long third 

 day to the crater, and enable the traveler to explore the 

 whole circumference. He says he felt no inconvenience 

 from the rarefaction of the air. This difiiculty in ascend- 

 ing high altitudes begins at the height of 12,000 or 13,000 

 feet, but does not appear to augment with the altitude. 

 In 1867, the writer of these lines ran a race with a fellow- 

 traveler on the side of Antisana at the bracing altitude of 

 lt),000 feet. All the peons with Dr. Reiss complained 

 of sickness, and one stout fellow bled at the nose. The 

 mules also suifered much above the altitude of 13,000 feet; 

 but his dog, although evidently troubled for breath, fol- 

 lowed him to the crater.* 



* For observations by the author on the Ecuadorian volcanoes, the reader 

 is referred to The Am. Jour, of Science for March, 1869, p. 242, and Septem- 

 ber, 1868, p. 203. 



