THE IMPENETRABLE SEA 



excess of that figure have been recorded. The maximum 

 wind velocity recorded in the British Isles was 125 miles 

 an hour at Costa Hill, Orkneys, on 31st January 1953. 

 But calculations from the enormous destruction caused 

 by tornadoes show that they can easily surpass 500 miles 

 an hour. 



A tornado which visited Mayfield, Ohio, U.S.A., on 

 the 4th of February 1842 struck with a fury that has 

 probably never been equalled in the history of modern 

 civilization. It was calculated by authorities of the time 

 to have a velocity of 682 miles an hour. Although the 

 figure has been disputed, there is no doubt that the wind 

 reached a velocity on that occasion many times greater 

 than that of ordinary tornadoes — if any tornado can 

 ever be described as "ordinary". 



Compared with such a wind, the Mistral — a cold, dry 

 wind which blows from the north-west in the Gulf of 

 Lyons, and which has often been described as a plague — 

 seems but a gentle zephyr. It blows for varying periods — 

 sometimes for as long as ninety days, is confined to the 

 coastal districts, and is announced by white ''cottony" 

 clouds which suddenly appear in a serene sky. 



The Bora is a wild, bleak wind that rushes down from 

 the Alps to the Adriatic and the Black Sea. It is a deafen- 

 ing, deadly wind, that has been known to overturn heavy 

 wagons and even carry horses and drivers great distances. 



Of the hot winds the dreaded Simoom of northern 

 Africa and Arabia is best known. Heralded by an evil- 

 looking yellow hue on the horizon, the Simoom raises 

 great clouds of dust and adds serious hardship to a desert 

 journey. The Sirocco of Sicily and Southern Italy is a 

 similar wind, but is less dry, being tempered by its 

 passage across the Mediterranean. Another hot wind is 

 the Harmattan, prevalent along the coast of Guinea and 

 below Cape Verde and Cape Lopez at certain times in 

 the year. 



Monsoons occur in the China Sea and the Indian 



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