104 British Association for the Advancement of Science. 
uary, 1838, which committed such dreadful ravages in England. 
A careful analysis of the information I have collected, leads me, 
(said Mr. O.) to the opinion that this was a small, but violent rota- 
- tory storm, moving forward at the rate of 30 or 35 miles per hour. 
The diameter of the rotating portion, I am not prepared to give, 
nor do I consider it at all certain that it could be ascertained, as 
it seems likely that the revolutions were not in contact with the 
earth. The tendency of this eddy, or violent whirling of the air, 
would of course, be to produce a vacuum in the centre. The air 
that forms the eddy being constantly thrown off in a slight de- 
gree spirally upwards, and dispersed on the upper portion of the 
atmosphere, the effect of this would be, to produce a strong cur- 
rent upwards. Now, supposing this large eddy to be perfectly 
stationary, there would be a rapid rush of air towards it from all 
sides, which would be drawn up and thrown off through this ro- 
tating circle, and dispersed with amazing rapidity above; but as 
it is moving on with great velocity, the air that is in the advance 
of the storm is not sensibly affected until the whirl is close upon 
it, while in the rear the motion of the air is greatly increased ; 
first, by the tendency of the air to rush into the great vortex of 
the storm; and secondly, by the motion onward of the vortex 
itself. This vortex or revolving column would increase in size 
upwards, so as somewhat to resemble a funnel ; it would, in fact, 
be similar in its shape and action to an immense water-spout; 
whether it was vertical or not is entirely a matter of conjecture, 
but I should consider it probable that it would incline in the direc- 
tion that the storm was moving, namely, to the N. E., and that 
it was an upper current that carried it in that dinedtione The 
greatest intensity of the storm in England was evidently across 
Lancashire and Yorkshire. I therefore conceive that the nucleus 
of the hurricane passed in a N. E. direction over these two coun- 
ties. ‘Towards the sides, however, a little current set in a S.and 
even slightly in a S. E. direction, on the S. side of the vortex; 
and in a N. W. and W. direction on the N. side, as before stated; 
but the main rush is behind. Our anemometer shows that we first 
felt a fresh S. wind with a slight bearing of E. in it, which very 
tly became more mg eee donddieinsia: in vio- 
lence, It then move nd e S. W. and became quite a 
hurricane, and contint ee a at first, but decreasing 
in <n during the remainder of the day. At Plymouth it : 
> = Peg aa 
. te 
. ' + 
+ 
aeingurennn)-<iligignnacennpnimnnnntictnlamesareaaaan 
