246 VOLCANIC ACTION. SECT. XXVI. 



enough to melt the snow at the poles, though so much 

 nearer to the center than any other part of the globe. 



The immense extent of active volcanic fire is one of 

 the causes of heat which must not be overlooked. 



The range of the Andes from Chili to the north of 

 Mexico, probably from Cape Horn to California, or even 

 to New Madrid in the United States, is one vast district 

 of igneous action, including the Caribbean Sea and the 

 West Indian Islands on one hand ; and stretching quite 

 across the Pacific Ocean, through the Polynesian Archi- 

 pelago, the New Hebrides, the Georgian and Friendly 

 Islands, on the other. Another chain begins with the 

 Aleutian Islands, extends to Kamtschatka, and from 

 thence passes through the Kurile, Japanese, and Phil- 

 ippine Islands, to the Moluccas, whence it spreads with 

 terrific violence through the Indian Archipelago, even 

 to the Bay of Bengal. Volcanic action may again be 

 followed from the entrance of the Persian Gulf to Mad- 

 agascar, Bourbon, the Canaries, and Azores. Thence 

 a continuous igneous region extends through about 1000 

 geographical miles to the Caspian Sea, including the 

 Mediterranean, and extending north and south between 

 the 35th and 40th parallels of latitude ; and in central 

 Asia a volcanic region occupies 2500 square geographical 

 miles. The volcanic fires are developed in Iceland in 

 tremendous force ; and the antarctic land recently dis- 

 covered by Sir James Ross is an igneous formation of 

 the boldest structure, from whence a volcano in high 

 activity rises 12,000 feet above the perpetual ice of 

 these polar deserts, and within 19 of the south pole. 

 Throughout this vast portion of the world the subterra- 

 neous fire is often intensely active, producing such vio- 

 lent earthquakes and eruptions that their effects, accu- 

 mulated during millions of years, may account for many 

 of the great geological changes of igneous origin that 

 have already taken place in the earth, and may occasion 

 others not less remarkable, should time that essential 

 element in the vicissitudes of the globe be granted, and 

 their energy last. 



Mr. Lyell, who has shown the power of existing causes 

 with great ingenuity, estimates that on an average twenty 

 eruptions take place annually in different parts of tho 



