with reference to the Views of Mr. Redfield. 429 



sumes the existence, have a property which he alleges to be ob- 

 servable in " all narrow and violent vortices, viz. a spirally 

 involute motion quickened in its gyrations as it approaches 

 towards the centre of the axis or whirl." 



32. But is it not evident, that if any mass of matter be made 

 to revolve by unequal and opposing forces, or by any other 

 than those resulting from the centripetal force, caused, as al- 

 ready described, by an ascending current, the gyration will not 

 quicken in proportion as the gyrating matter may be nearer 

 the centre, but on the contrary 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 from the confluence caused by an ascending or de- 

 scending concentric current. So far therefore as Mr. Red- 

 field'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 to refute those which he 

 upholds. 



33. To conclude whether or not the efforts which I have 

 made, to show that the phaenomena of tornadoes and hurri- 

 canes arise from an electrical discharge by convection, be justi- 

 fiable, I think it will be conceded that any theory of storms 

 which overlooks the part performed by electricity must be 

 extremely defective. 



34. Both by Messrs. Espy and Redfield the influence of 

 this agent in the phaenomena of nature is entirely disregarded, 

 although with the storms, which have been especially the sub- 

 ject of their lucubrations, thunder, lightning, and convective 

 discharge are most strikingly associated. 



35. I will conclude with subjoining the following proposi- 

 tions, inferences, or allegations; which are so evident to my 

 mind, that I am at a loss to understand that they have not 

 had a similar influence upon the minds of all who are con- 

 versant with the science of electricity. 



36. Our experiments make us familiar with two processes 

 of electrical discharge. In one of these electricity passes in 

 the form of sparks or flashes; in the other it may be con- 

 veyed without any perceptible evolution of light, by the alter- 

 nate or successive contact of intervening bodies with the ex- 

 cited surfaces, as, for instance, by means of pith-balls, pen- 

 dula, or a blast of air. The former process has been desig- 

 nated by Faraday as disruptive, the latter as convective dis- 

 charge. 



37. The disruptive process being exemplified by lightning, 



