H. S. Whitfield on Tornadoes in the Southern States. 105 
above. The descending stream, fed by oblique tributaries from 
all points of the compass, begins to gyrate. From centrifugal 
force result rarefaction, cooling, and further condensation. The 
center of the vortex is a partial vacuum, and from below a 
e two columns meeting, vas mi 
thrown off by centrifugal force in all directions, and the cloud 
this is the termination of all these storms. They are of varia- 
ble duration and extent, continuing until the equilibrium of 
the atmosphere is restore 
Loomis has explained, but not to entire satisfaction, the 
cause of the northward inclination of tornadoes. He nightly 
ascribes it, however, to the decreasing diameters of the succes- 
Sive parallels of latitude. If a tornado should form on a par- 
lel of 45 degrees, its vertical axis would make an angle of 45 
degrees with the earth’s axis of rotation. It follows, then, as 
Would readily appear from adiagram, that the currents descend- 
Ing obliquely to the vortex on the south side, would approach 
: axis 
be greater than that of the latter, and, consequently, velocities 
_ Corresponding, there would result a greater centrifugal tendency 
bag northeast than on the southwest of the vortex; and the 
: = lect Increases with the latitude. 
