306 ^ Mr. Redfield's Reply to Dr. Bare. 



magnitudes and activity ; some of which, may opcasionally become 

 extended and spin on an upright and moving axis, with that vio- 

 lent and continued action which characterizes the tornado or water 

 spout. Indeed, it must be obvious, that uniformly direct lines of 

 motion, belong not to our atmosphere or system. But, as before 

 observed, I have here no special concern with the origin of these 

 or other vortices; the simple fact of their existence being all that 

 is necessary for me to maintain. 



Dr. Hare then proceeds to state, that in former papers on the 

 causes of tornadoes, he has adduced facts and arguments " tend- 

 ing to prove that the proximate cause of the phenomena of a tor- 

 nado is an ascending current of air, and the afflux of wind from 

 all points of the compass to supply the deficiency thus created." 

 He also states, that "in this mode of viewing the phenomena, no 

 difference of opinion exists between Espy and himself, hov/ever 

 they may differ respecting the cause of the diminution of atmos- 

 pheric pressure," (fcc. [19-20.] 



I have no desire to offer strictures upon the views of a respected 

 professor of science ; but it seems proper here to inquire how an 

 ascending current of air is thus obtained, and whether this effect, 

 which perhaps may be due only to an excess of lateral and sub- 

 jacent pressure, on the exterior of the tornado, be not here adduced 

 as the cause of the effect. 



Dr. Hare has been ^ed to consider gyration as a casual and 

 not an essential feature''' in tornadoes, and he adduces the dislo- 

 cation and partial turning of a chimney top on its base, in the 

 New Brunswick tornado, as being due to a local whirl within the 

 body of the tornado, and proving that in tornadoes and hurricanes 

 there are local whirls, p. 144. [21.] 



I have long since ascertained that local whirlwinds are not of 

 very rare occurrence in great whirlwind storms ; the New Bruns- 

 wick tornado itself having been one of several violent local whirl- 

 winds which occurred within the limits of a somewhat remarka- 

 ble storm of the above character. This tornado also sent off a 

 duplicate vortex or whirl not long after its passing the Raritan ; 

 the path and violent effects of both whirlwinds having been dis- 

 tinctly traced on a field of unripe grain ; the smaller one branch- 

 ing off to the right of the main track, where, after causing some 

 prostrations, it passed into the Raritan marshes, and was no more 

 seen. But the whirling motion so far from being only of " casual" 



