142 Objections to Mr. Redfield’s Theory of Storms. 
mainly the cause of atmospheric currents. But in the absence of 
calorific and electrical reaction, what other effect could gravita- 
tion have unless that of producing a state of inert quiescence. 
The part which it performs in the mechanism of nature is well 
illustrated by that which it performs through the medium of a 
clock weight, which is of no use without being wound up. . 
8. It is remarkable that the author after ascribing the trade 
winds to momentum, as the antagonist of gravitation, loses sight 
of it in this summing up of the causes of atmospheric currents. 
9. If, as Mr. Redfield alleges, the minuteness of the altitude of 
the atmosphere in.comparison with its horizontal extent, be an ob- 
jection to any available currents, being induced by calorific rarefac- 
tion, wherefore should not momentum, or any other cause dimin- 
ishing or counteracting the influence of his favorite agent, gravity, 
_ be on the same account equally inefficient ? 
10. Assuming that the motion of the air in hurricanes, is always 
eiralergs Mr. Redfield considers gyration as a cause of these ter- 
rible meteors. How far his language on this. subject is reasona- 
ble or consistent, may be seen from the following paragraph, 
which I quote from one of his essays. See ie een, 
Vol. xxv, p. 125. 
11. “ Notwithstanding these general and selatceinaie hortade 
tal movements, the equal distribution of the atmosphere over the 
surface of the globe, which resulis from gravitation, tends to pre- 
vent any very rapid or violent motion in any specific direction, and 
consequently to prevent violent and destructive winds. But owing 
ie the tenilancy 4 all fluid matter to run into whirls or cirecutts, 
to the infl of unequal or opposing forces, a rota- 
tive ‘movement of suninessured:,violence.is sometimes produced. 
This peculiar movement, which in its most active state is some- 
times distinguished by the name of tornado or hurricane, assumes 
every possible variety of position, appearance, velocity and extent, 
ond 4 as the only known cause of violent and destructive winds or 
3,7? a 
old. Agreeably to this paragraph, gravitation in lian of being, as 
ithe main basis of winds.and-storms,.tends te 
produe that e f the at over the sce 
of the 1obe dnsi 
13. But if it ry ie expansion,: nor less 
city, be the cause of are they produced? 
