of very small area, from a few feet to a mile or two in diameter, 

 but of great intensity. Such storms are properly called torna- 

 does and occur most commonly in inland regions. 



Hurricanes or typhoons are cyclonic storms a few hundred 

 miles in diameter and of great intensity originating over the ocean 

 in the tropics and passing, in the northern hemisphere, a little 

 north of west to about latitude 30°, where they commonly re- 

 curve to the northeast. Such storms are known as hurricanes in 

 the West Indies and as typhoons in the East Indies. They de- 

 crease in area and increase in intensity until they recurve, when 

 they spread out and become less violent. Hurricanes are the 

 most destructive storms that visit the United States and while 

 their effects are most severe on the Gulf and South Atlantic Coasts 

 they sometimes have a maximum effect much farther north, as in 

 the hurricane of September, 1877, which did general damage 

 throughout northeastern United States and Canada. Ninety 

 per cent of the West Indian hurricanes occur in August, September, 

 and October. The most serious damage at Charleston has been 

 in late August or early September. Some four hundred of these 

 storms have been recorded in the past four hundred years, but 

 the same place in the West Indies or United States is visited only 

 about once in ten or fifteen years. 



Unfortunately, some of the most dangerous hurricanes touch 

 land for the first time on the South Atlantic Coast, as was the 

 case this year, while a large proportion of those reported in the 

 West Indies recurve before reaching the coast of the United States. 

 These circumstances explain the inability of the Weather Bureau 

 to forecast the coming of storms hke that of August, 1911, until 

 regular wireless reports are received from ships in the area north 

 of the West Indies. Occasionally the point of recurving is 

 carried much farther west into the Gulf of Mexico, and it was a 

 hurricane of this type that destroyed Galveston on September 8, 

 1900. The motion of the hurricane center is so slow that the 

 heavy sea which it causes passes far ahead of the storm and may 

 give warning of its approach two or three days in advance. 



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