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WHIRLWINDS. 



Whirlwinds are common about Cabul, commencing as soon as the 

 sun has attained a certain degree of power. 



In all cases they assume the shape of a cone, the point of which being 

 a tangent on the earth's surface : the cone varies in shape, is generally 

 of a good diameter, occasionally much pulled out, some being 2,300 

 feet in height, the currents are most violent at the apex. 



They come and go in all directions, even after starting, not always 

 preserving the original direction. They are less common on days in 

 which winds prevail from any given direction, and vary much in inten- 

 sity from a mere breeze, lightly laden with dust and with no tortuo- 

 sity, to a violent cone of wind, capable of throwing down a soldari. 



Northerly winds are prevalent here from 1 or 2 p. m. untill 8 or 9 

 p. m., occasionally they only commence in the evening, when they are 

 obviously due to the rarefaction of the air of the vallies by the great 

 heat of the sun, amounting now to 100° at 3 p. m., and the vacuum 

 being supplied by gusts from the high mountains to the north and 

 north-east. 



