278 REACTION OF THE INTERIOR OP THE EARTH 



our present information, the maximum elevation of 

 all the mountains of the new continent. The mean 

 height of the Sahama group is 22,008 feet, or 586 higher 

 than Chimborazo. Then follow in rapidly diminishing 

 elevation Cotopaxi, Arequipa (?), and Tolima, between 

 18,877 and 18,129 feet. ' I give unaltered, in what look 

 like very exact numbers, the results of measurements 

 which, unfortunately, are necessarily compounded of 

 trigonometric and barometric determinations ; but I do 

 so with the view of inciting others to repetition and 

 correction. Of the Chilian group of volcanoes a few 

 only, out of the number of 24 mentioned in the table, 

 have had their elevations determined; and these are 

 mostly only the southernmost, or those between the 

 parallels of 37 20' and 43 40', from Antuco to Yantales, 

 and which are also the lowest, having only the inconsi- 

 derable elevation of from 6000 to a little more than 

 8000 feet. In Tierra del Fuego the summit of Sar- 

 miento, covered with perpetual snow, rises only (ac- 

 cording to Fitz Roy) to the height of 6821 feet. From 

 the volcano of Coquimbo to the volcano of San Clemente, 

 the distance is 968 miles. 



For the continual activity of several of the Chilian vol- 

 canoes we have the important testimony of Darwin ( 404 ), 

 who regards Osorno, Corcovado, and Acongagua as 

 decidedly still active, and the evidence of Meyen, 

 Poppig, and Gray, who ascended Maipu, Antuco, and 

 Peteroa ; of Domeyko, the astronomer Grilliss, and Major 

 Philippi. The number of still-burning craters may be 

 taken at thirteen only five less than in the Central 

 American group. 



We now turn from these American continental 



