THEORY CONFIRMED BY PHENOMENA. 39 



we consider that the vortex moved with a velocity of fifty 

 miles an hour from the south west to the north east, we will 

 readily perceive that, as it would require perhaps twenty or 

 thirty minutes for the drops of rain to be carried up to their 

 greatest elevation, and to fall down to the earth, during 

 which time the up-moving column would move forward 

 twenty or twenty-five miles, neither hail nor rain could ap- 

 pear in front of the vortex, and as it could not fall in the 

 middle of the spout, being prevented by the force of the 

 ascending air, whatever fell between the two bands of hail 

 must have descended in the hinder part of the ascending 

 column, where it would not be likely to descend, on account 

 of its upper part leaning forwards. 



70. The correctness of this explanation acquires addi- 

 tional probability from the fact that, in hail storms, the hail 

 almost always precedes the rain, as appears from the facts 

 collected by Pouillet. After mentioning the facts connected 

 with this remarkable storm, this highly enlightened philoso- 

 pher says : " In explaining the meteor hail, there are but 

 two difficulties; but these are great, and we may say, in 

 advance, they remain above all the efforts which have been 

 made to resolve them. 



" First. To explain how the cold is produced which con- 

 geals the water, and then to show how a hailstone which 

 has acquired sufficient volume to fall by its own weight, 

 remains yet suspended in the air during all the time neces- 

 sary to acquire a volume fourteen or fifteen inches in cir- 

 cumference." 



These two difficulties have already been fully explained. 

 But the power of the theory does not stop here. It explains 

 all the showers of dust, and rains of blood, (which are only 

 water holding clay in solution) of which we have a great 

 many well authenticated accounts. For, when the vortex 

 reaches down to the surface of the earth, it is able to carry 

 up large quantities of earth, as will appear from the follow- 



