227 



and constant, than at present, were the temperature uniform all over 

 the globe, and yet denies that he represents the agency of heat as 

 unnecessary to the existence of winds. 



As if affording support to his hypothesis, he continues his effort to 

 show that there has been gyration during certain tornadoes, after it 

 has been demonstrated that such gyration, being attended, as he has 

 admitted, by an upward current about the axis, and an acceleration 

 of velocity towards the centre of motion, is irreconcilable with whirl- 

 winds arising from the causes to which he has referred, and which 

 have been inconsistently admitted by him to be productive of a cen- 

 trifugal force, determining the air towards the circumference. 



Founding an accusation of error, upon a mistake of his own, in 

 alleging that, when a storm travels from south-west to north-east, 

 whirling to the left, the progressive motion will not conspire with 

 that of the whirl on the south-eastern limb, so as to be productive of 

 a south-wester of pre-eminent fury : whence this inference, that Mr. 

 Redfield cannot perceive one of the most palpable and inevitable con- 

 sequences of his own doctrine, even after it has been pointed out to 

 him.* 



Subsequently to the preparation of his second essay respecting the 

 errors of Redfield, Dr. Hare had found, in Dove's essay on the law 

 of storms, other errors, of which he would now give a sketch. 



Treating it as sufficient to show a cause of gyration in a wind blow- 

 ing towards the equator, without assigning any cause for the pecu- 

 liar violence of the wind, which, being thus made to whirl, is converted 

 from a moderate trade wind into a furious hurricane. 



Not perceiving that whatever bends the wind from a straight course, 

 must cause a loss of some portion of its velocity ; so that gyration 

 must have the inverse effect of contributing to the unexplained acces- 

 sion of violence which accompanies the transformation alluded to : 

 and further, that a travelling storm, as every whirlwind is represented 

 to be, cannot be sustained unless the causes of violence travel with it ; 

 since any momentum, locally acquired, must soon be expended ; and 



* Agreeably to the observations collected by Loorais, the storms, in which 

 the well known sudden change from south-west to north-west occurs, travel 

 from north-west to south-east. But a change from the latter to the former di- 

 rection can only take place in a whirlwind in travelling from south-west to 

 north-east. Besides, as such storms have to cross the Alleghany mountains, 

 is it not inconceivable that they should whirl? See Transactions, A. P. S. 

 Vol. VII. 



Can any mass of air be imagined to rotate, while a range of mountains is so 

 situated as to cut it nearly in twain? 



