W. Ferrel—Oyclones, Tornadoes and Waterspouts. 41 
the cyclone exists. It depends also very much upon the direc- 
tion in which the greatest humidity of the air lies. The pro- 
gressive motion of the cyclone is generally greater than that of 
the air, even in the upper regions, and consists rather in the 
continual formation of new cyclones a little in advance of the 
ones, the latter gradually subsiding,.and this new formation 
is mostly likely to occur in the direction of greatest moisture. 
Areas of High Barometer.—These arise from the intersecting 
and overlapping of the circular belts of high barometer of dif- 
ferent cyclones both fixed and progressive. In consequence of 
the gradients arising from the general motions of the atmo- 
sphere combined with those of the fixed cyclones and all the 
other irregularities, the gradients and isobars become very 
irregular. When to these are added the irregularities of pro- 
gressive cyclones following and impinging upon one another 
this irregularity becomes still much greater, so that it must 
frequently happen that there are areas in which the barometer 
stands higher than at any of the surrounding places, just as on 
a rough sea where numerous broad waves interfere and cross 
one another, the surface of the sea has elevations and depres- 
sions, not in the form of waves and troughs, but rather of ele- 
vated and depressed areas approximating more nearly to a 
circular form. The isobars of these areas are generally some- 
what irregular, but still as they enclose an area, and the winds, 
according to a well-established law, must blow with a certain 
to run out. If the water is entirely at rest when the flow 
commences, there will be only a radial and very gentle motion 
of the water from all sides toward the center, without any 
gyratory motion, but if it has the least gyratory motion in its 
initial state, even entirely imperceptible, it will run into very 
rapid gyrations before reaching the center. 
