TRUE VOLCANOES. 371 



great volcano of Tanaga, already delineated by Sauer; 

 the Rat Islands, and the somewhat distant islands of B'ynia, 

 among which, as has been already observed, Attu forms the 

 connecting link to the Commander group (Copper and 

 Behring's Isles) near Asia. There seems no ground for the 

 often-repeated conjecture that the range of continental vol- 

 canoes in the direction of NN.E. and SS.W. on the penin- 

 sula of Kamtschatka first commences where the volcanic 

 fissure of upheaval in the Aleutian Islands intersects the 

 peninsula beneath the ocean, the Aleutian-fissure thus form- 

 ing, as it were, a channel of conduction. According to 

 Admiral Liitke's chart of the Kamtschatkan Sea (Behring's- 

 Sea) the island of Attu, the western extremity of the Aleu- 

 tian range, lies in lat. 52 46', and the non-volcanic Cop- 

 per and Behring's Islands in lat. 54 30' to 55 20', while the 

 volcanic range of Kamtschatka commences under the paral- 

 lel of 56 40' with the great volcano of Schiwelutsch, to the 

 west of Cape Stolbowoy. Besides, the direction of the 

 fissures of eruption is very different, indeed, almost opposite. 

 The highest of the Aleutian volcanoes, on Unimak, is 8076 

 feet, according to Liitke. Near the northern extremity of 

 Umnak, in the month of May, 1796, there arose from the 

 sea. under very remarkable circumstances, which have been 

 admirably described in Otto von Kotzebue's " Entdeckungs- 

 reise" (Bd. ii, s. 106), the island of Agaschagokh (or St. 

 Johannes Theologus) which continued burning for nearly 

 eight years. According to a report published by Krusen- 

 stern, this island was, in the year 1819, nearly sixteen 

 geographical miles in circumference, and was nearly 2240 feet 

 high. On the island of Unalaschka the proportions of the 

 trachyte, containing much hornblende, of the volcano of 

 Matuschkin (5474 feet) to the black porphyry (?) and the 

 neighbouring g anite, as given by Chamisso, would deserve 

 to be investigated by some scientific observer acquainted 

 with the conditions of modern geology, and able to examine 

 carefully the mineralogical character of the different kinds 

 of rocks. Of the two contiguous islands of the Pribytow 

 group, which lie isolated in the Kamtschafckan sea, that of 

 St. Paul is entirely volcanic, abounding in lava and pumice, 

 while St. George's Island, on the contrary, contains only 

 granite and gneiss. 



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