146 Objections to Mr. Redfield’s Theory of Storms. 
produced, not by a deficit of pressure about the axis, but by un- 
equal and opposing forces acting externally, in any competent 
way whatever, is it not evident that any deficit of pressure about 
the axis, consequent to the resulting centrifugal force, could only 
cause in the atmosphere a descending current, while it could not 
tend in the slightest degree to carry solids or liquids aloft? It must 
be obvious, that the stratum of air on the earth’s surface, partak- 
ing of the circular motion, must also partake of the centrifugal 
momentum, and of course would have the inverse of any dispo- 
sition to rush towards the axis so as to be productive of a vertical 
blast. Meanwhile the air being rendered rarer by the centrifugal 
momentum imparted as above alleged, ponderable bodies envel- 
oped by it would have their gravity less counteracted than usual, 
and consequently far from acquiring any tendency to rise, would 
be unusually difficult to elevate. 
28. Icannot help thinking that as respects the application of his 
“rotary theory” to account for the upward movement which ap- 
to be essential to ence these arguments will amount 
to a “reductio ad absurdum 
29. Mr. Redfield infers that the whirlwinds of which he assumes 
the existence, have a property which he alleges to be observable 
in “all narrow and violent vortices,” viz. “a spiral involute motion 
quickened in its gyrations, as it approaches towards the centre of 
the axis or whirl.”* But is it not evident, that if any fluid mass 
be made to revolve by unequal and opposing forces, or by any other 
than those resulting from the centripetal force, caused, as already 
ee; by suction at the axis, the gyration will not quicken, in 
as the gyrating matter may be nearer the centre ; but on 
Giitiebiesey, will be slower as the distance from the axis may be 
less? It appears to me that the only case in which gyration is 
found to quicken in proportion as the matter involved approaches 
“the vortex, is that which results froma confluence caused by an 
ascending or descending current at the axis of the whirl. 
30. So far therefore as Mr. Redfield’s observations confirm the 
idea that the whirling motion in tornadoes quickens towards the 
- centre, it tends to confirm the opinions which he combats, and t0 
refute those which he upholds. 
31. Although the efforts which I have made to show that the 
eR. tornadoes and hurricanes arise from electrical reac- 
~ * See this Journal, Vol. xxx1, p. 130. 
ot 
Ae 38 Soo 
