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The National Geographic Magazine 



at last break and let them fall with a 

 musical crash into countless disappearing 

 fragments. 



For many days the ice runs. The up- 

 stream branches are cleared first, and 

 steamboats and smaller craft follow 

 closely the retreating ice. Some daring 

 travelers have tied their boats to large 

 chunks of ice in order to take advantage 

 of the greater speed of the under current. 



It is usually past the middle of June 

 before the mouth of the Yukon is free 

 from ice, and the termination of the 

 annual break-up is announced by the 

 "chug," "chug," of the welcome upcoming 

 steamboat, laboring against the current. 



A most beneficent phenomenon ac- 

 companies the spring "break-up," with its 

 outrushing flood of more than three mil- 

 lion tons of water per minute. During the 

 extreme high stage of water, which lasts 



for perhaps two or three weeks, great 

 sections of the heavily wooded bank are 

 undermined and swept away. The ma- 

 jestic spruce trees and tamaracks and 

 birches which covered them topple over 

 and are swept down by the current, 

 along with immense quantities of drift- 

 wood from the forest beds. The entire 

 accumulation, amounting to thousands of 

 cords of wood, is discharged into Bering 

 Sea, whose restless waves and shifting 

 winds scatter this fuel and pile it up on 

 barren shores hundreds of miles distant. 



The prospect presented by these arctic 

 shores is as bleak and desolate as can be 

 imagined. The landscape is destitute of 

 timber as far as the eye can see, and the 

 inhabitants of that inhospitable region 

 have had occasion to be very grateful for 

 these peculiarly valuable contributions 

 from the distant valley of the Yukon. 



MOUNT VESUVIUS 



VESUVIUS has been violent many 

 times since the notable eruption 

 of 70 A. D., when Pompeii and 

 Herculaneum were buried, but the erup- 

 tion of 1906 will rank among the most 

 destructive. Many villages were over- 

 whelmed by streams of lava and falling 

 ashes, so that years will elapse before the 

 country recovers from the devastation. 

 The mountain is reported to have lost 

 about 800 feet in height, but it does not 

 take the volcano long to rebuild. Vesu- 

 vius has now been watched for about two 

 thousand years, and we are better ac- 

 quainted with it than with any other vol- 

 cano, but its actions are so mysterious 

 that practically nothing is known of the 

 causes which make it break out at inter- 

 vals with such violence. 



No five years in history have been so 

 noted for volcanic disturbances as the 

 years 1902-1906. The explosion of 

 Mont Pelee, which destroyed 30,000 

 people; the eruption of Santa Maria in 

 Guatemala a few months later, which 

 likewise swept away thousands of people 



and wrecked many miles of fertile plan- 

 tations ; the activity of Colima in Mexico, 

 and of Mauna Loa in Hawaii, and now 

 this latest eruption of Vesuvius, form an 

 unprecedented series of disasters. They 

 serve to emphasize our ignorance of vol- 

 canic action ; and yet this ignorance is not 

 to be wondered at, for no systematic 

 study of volcanic action has ever been 

 made. Commissions have been sent to 

 study individual volcanoes — Vesuvius, 

 Mauna Loa, Krakatoa, Mont Pelee, etc. — 

 but no prolonged comparative investiga- 

 tion has been made of all of them. Prob- 

 ably no field of scientific inquiry would 

 yield such valuable results as a careful 

 study of the volcanoes of the world. 



Near the shore west of Naples is 

 Monte Nuovo, or new mountain, a hill 

 440 feet high, cast up by volcanic action 

 during a few days in September, 1538. 

 All about it are volcanic hills of earlier 

 origin, and two islands bordering the bay 

 are also volcanic. 



About 150 miles south of Vesuvius is 

 Stromboli, which is always active and is 



