1890. | VEEDER—FORCES IN DEVELOPMENT OF STORMS. 61 
atmosphere as exists over enormous areas in Asia during winter, without 
strong winds, in spite of the steep barometric gradient, is a phenomenon 
that demands adequate explanation. 
It remains to discuss the mechanism of storm-action and inquire 
whether it is consistent with the views here presented. An inspection 
of any weather map shows that the air flows outward in every direction 
from centers of high barometer, and that in the northern hemisphere it 
has a rotary movement from left to right about such centers. It is 
probable, although not beyond question, that this deflection toward 
the right is due to the fact that air particles, moving upon each 
other with very little friction, when advancing toward the equator 
tend to be left behind, and moving in the opposite direction are 
projected forward, thus creating a whirl. The effect of the lateral 
interference of two such rotating anti-cyclones is an antagonism of 
air currents from opposite directions producing a series of smaller 
eddyings and whirls from right to left along their line of contact, 
and likewise producing cloud formation and precipitation. These 
local whirls derive their energy from the upper currents whose 
velocity has not been checked by friction with the earth’s surface. The 
direction in which these whirls advance is also determined by the upper 
currents. Thus tornadoes and waterspouts first appear at an elevation 
above the surface of the earth and extend downward, whirling about, 
and at the same time moving forward in a direction determined by 
the anti-cyclonic circulation. Instead of being due to an uprush 
of warm air they are in some instances certainly attended by a 
projection downward of cold air, which has a boring motion, pene- 
trating the lower strata. Thus a waterspout which came aboard of 
a ship was found to have snow at its center. At the instant a 
thunder storm bursts forth over any locality there is an immediate 
fall in temperature and rise of barometric pressure, showing a very 
decided projection downward of cold air rather than an uprush of warm 
air. Observations in balloons and on mountain tops have brought to 
light the fact that the air above storm centers is very cold, and above 
centers of high barometer very warm. With such a distribution of 
temperature if the circulation of the atmosphere is due to convection 
currents it would seem that the direction of the movement ought to be 
exactly opposite to that which appears on the weather maps. 
But according to the hypothesis here outlined temperature and 
convection currents are of secondary importance. The bringing of 
warm air from the tropics, or the bringing of cold air from the polar 
regions, is the effect and not the cause of the re-distribution of pressure. 
