NOTES. Ixxxiii 



ment by a French naval officer, M. Dolley, kindly communicated to me in Paris 

 by Capitaine Alphonse de Moges, in 1826. Dolley found the summit of Are- 

 quipa 10,928 feet, and that of Charcani 11,857 feet above the high plain in 

 which the town of Arequipa is situated. Taking the height of the town at 

 7850 feet, from the barometric measurements of Pentland and Eivero (Pentland 

 gives 7852 feet in his table of heights, in the third edition of Mary Somerville's 

 Physical Geography, 3rd. ed. vol. ii. p. 454 ; and see Eivero, in the Memorial de 

 Ciencias naturales, t. ii. Lima, 1828, p. 65; Meyen, Eeise um die Erde, Th. II. 

 1 835, S. 5), we obtain, from Dolley's trigonometric operation, for the volcano of 

 Arequipa 18,876 feet, and for that of the volcano of Charcani 19,708 feet. 

 But the above-cited table of altitudes of Pentland gives for the volcano of Are- 

 quipa 20,320 feet (19,065 Paris feet), which is more than 2000 feet above 

 Pentland's estimate in 1830, and only too identical with Hanke's result in 1796, 

 which was 19,080 Paris feet.l On the other hand, in the Anales de la Uni- 

 versidad de Chile, 1852, p. 221, the same volcano is given so low as 18,373 

 feet ! A melancholy state of hypsometrical information ! 



( 37 ) p. 248. Boussingault, accompanied by a highly informed companion, 

 Colonel Hall, almost reached the summit of Cotopaxi. They arrived, according 

 to barometric measurement, at a height of 18,862 feet. There remained only a 

 short distance to the margin of the crater, but the exceeding looseness of the snow 

 forbade further progress. Perhaps Bouguer's result may have been rather too 

 small, as his complicated trigonometric computation is dependent on the height 

 of Jhe town of Quito. 



( 371 ) p. 248. Sahama, which Pentland (Annuaire du Bureau des Longi- 

 tudes pour 1830, p. 321) distinctly affirms to be a still active volcano, is situ- 

 ated, according to his new map of the valley of Titicaca (1848), east of Arica, 

 in the western Cordillera. It is 928 feet higher than Chimborazo; and the 

 proportion of its height to that of the lowest Japanese volcano Kosima, is as 

 30 to 1. I have abstained from placing in the fifth group the Chilian Acon- 

 gagua, which, according to its latest measurement, by Captain Kellett in the 

 Herald in 1845, is 23,004 feet high, because from the opposite opinions of 

 Miers (Voyage in Chili, vol. i. p. 283) and Charles Darwin (Journal of Ee- 

 searches into the Geology and Natural History of the different Countries visited 

 by the Beagle, 2nd ed. p. 291) it remains somewhat doubtful whether this 

 colossal mountain is a still active volcano. Mary Somerville, Pentland, and 

 Gillies (Naval Astron. Exped. vol. i. p. 127) deny its being so. Darwin says': 

 " I was surprised at hearing that Acongagua was in action the same night 

 (15th Jan. 1835), because this mountain most rarely shows any signs of 

 action." 



