INDEX 617 



W. 



Whirls in the atmosphere (Margules) 509-514 



Whirlwind, about a barometric minimum 157, 161 



barometric maximum 158, 162 



cause of 20 



progressive motion of 112 



velocity of 154-162 



Wind measurements 104 



Wind systems 181, 192, 212, 232 



Winds, ascending parallel, system of 182, 198 



influence of earth's surface on 232 



ocean and land, systems of 212 



relation to air pressure 58 



relation to vertical currents 122 



trade, causes of (Hadley) 5 



