28 On the prevailing Storms of the Atlantic Coast. 
3. The regular and obvious proportion which.the several diame- 
ters of the storm and whirlwind, and their rate of progression, bear 
to their duration, at each point over which they pass. 
4. The different and opposite, or nearly opposite directions in 
which the wind is found to blow upon the opposite sides of the track, 
and also upon the opposite marginal portions, of both the storm and 
the whirlwind. 
The last consideration, if established, hardly falls short of demon- 
strative evidence of the supposed identity mn the mode of action in 
these different masses of moving atmosphere. Every person, on ex- 
-amining the track of a destructive whirlwind, where it has passed 
through a forest, will, in crossing that track, often find the trees pros- 
trated in exactly opposite directions, and it is obvious that this effect — 
must necessarily follow, as the result of the acknowledged cause, a 
circular, or rotative force in the whirlwind. The same effect was 
equally apparent, only on a larger line of observation, after the storm 
or hurricane of 1821, as already described. ‘The same general evi- 
dence of a sudden or a progressive change in the direction of the 
wind, runs through all the accounts which we have given, or which it 
is in our power to submit, in relation to other storms. 
In relation to whirlwinds of the smaller class, we may here take 
occasion to remark, that it is not conceived to be essential to the 
character of a whirlwind, that its axis of rotation should occupy a ver- 
tical position, or one but slightly inclined to the plane of the horizon. 
On the contrary, the axis, or center of gyration, in whirlwinds of a 
limited character, may, and probably often does, occupy a horizontal 
position at a considerable height in the atmosphere. This variety of 
whirlwind is presumed to enter largely into the formation of thunder- 
storms and squalls, and particularly hail-storms. 
Having attempted to establish the circumrotative character of the 
south-east storm which has been described, we are led to inquire 
whether other south-easterly storms possess the like character ; and 
whether this be also an attribute of the north-eastern storms of our 
coast, and also what constitutes the specific difference of character 
in these storms. 
If the foregoing views be sufficiently established, it must follow, 
that the direction of the wind at a particular place, forms no part of 
the essential character of a storm, but is only incidental to that par- 
ticular portion or parallel, of the rout or track of the storm which 
may chance to become the point of observation. We have seen that 
