TRUE VOLCANOES. 



remarkable in those places where it depends upon the situa- 

 tion and extension of fissures, which, usually parallel to each 

 other, pass through great tracts of country in a linear direc- 

 tion (like Cordilleras). Thus, to mention only the most im- 

 portant series of closely-approximated volcanoes, we find in 

 the new continent those of Central America, with their ap- 

 pendages in Mexico ; those of New Granada and Quito, of 

 Peru, Bolivia, and Chili; in the old continent the Sunda Isl- 

 ands (the Indian Archipelago, especially Java), the peninsu- 

 la of Kamtschatka and its continuation in the Kurile Islands, 

 and the Aleutian Islands, which bound the nearly-closed Beh- 

 ring's Sea on the south. We shall dwell upon some of the 

 principal groups ; individual details, by being brought to- 

 gether, lead us to the causes of phenomena. 



The linear volcanoes of Central America, according to the 

 older denominations the volcanoes of Costa Rica, Nicaragua, 

 San Salvador, and Guatemala, extend from the volcano Tur- 

 rialva, near Cartago, to the volcano of Soconusco, over six 

 degrees of latitude, between 10 9' and 16 2 7 , in a line the 

 general direction of which is from S.E. to N.W., and which, 

 with the few curvatures which it undergoes, has a length of 

 540 geographical miles. This length is about equal to the 

 distance from Vesuvius to Prague. The most closely-ap- 

 proximated of them, as if they had broken out upon one and 

 the same fissure only 64 miles in length, are the eight volca- 

 noes situated between the Laguna de Managua and the Bay 

 of Fonseca, between the volcano of Momotombo and that of 

 Conseguina, the subterranean noise of which was heard in 

 Jamaica and on the highlands of Bogota in the year 1835, 

 like the fire of artillery. In Central America and the whole 

 southern part of the new continent, and generally from the 

 Chonos Archipelago, in Chili, to the most northern volcanoes 

 of Mount Edgecombe, on the small island near Sitka,* and 

 Mount Elias, on Prince William's Sound, for a length of 

 6400 geographical miles, the volcanic fissures have every 

 where broken out in the western part, or that nearest to the 



* Mount Edgecombe, or the St. Lazarus mountain, upon the small 

 island (Croze's Island, near Lisiansky) which is situated to the west- 

 ward, near the northern half of the larger island Sitka or Baranow, in 

 Norfolk Sound, was seen by Cook, and is a hill partly composed of 

 basalt abounding in olivin, and partly of feldspathic trachyte. Its 

 height is only 2770 feet. Its last great eruption, which produced 

 much pumice-stone, was in the year 179G. (Lutke', Voyage autour du 

 Monde, 1836, t. iii., p. 15.) Eight years afterward Captain Lisiansky 

 reached the summit, which contains a crater-lake. He found at that 

 time no signs of activity any where on the mountain. 



