a storm commencing at E.N.E. passes off at S.S.W. after the wind has
veered E., E.S.E., S.E., S.S.E., and S., being in the order of the
letters in the upper line and contrary to their order in the lower. One
commencing at E.S.E. passes off at S.S.E. right-hand semicircle. In the
higher latitudes a ship taking the storm at E.N.E. will be in the
left-hand semicircle, and the hurricane will pass off at N.N.E. These
changes are rendered very apparent by moving the hurricane circle in the
direction in which the storm is expected to proceed.

Fig. 2 represents the whirl and hurricane winds in the south.

[Illustration: Fig. 2]




CHAPTER II.

PHÆNOMENA OF ATMOSPHERIC WAVES.


Professor Dove of Berlin has suggested that in the temperate zones the
compensating currents of the atmosphere necessary to preserve its
equilibrium may be arranged as parallel currents on the _surface_, and
not superposed as in or near the torrid zone. His views may be thus
enunciated:--That in the parallels of central Europe the N.E. current
flowing towards the equator to feed the ascending column of heated air
is not compensated by a current in the upper regions of the atmosphere
flowing from the S.W. as in the border of the torrid zone, but there are
also S.W. currents on each side the N.E., which to the various countries