INTRODUCTION. XXXI 



and as Col. Reid had distinctly stated in his letter to Sir David, 

 already referred to, that he had actually seen, from the government 

 house at Bermuda, by means of a telescope, the water-spout re- 

 volving like the hands on the dial plate of a watch, there could be 

 no doubt that we were at variance about facts. This explicit and 

 distinct observation of a rotatory motion by so able and accurate 

 an observer as Col. Reid, was worth a thousand inferences. As 

 to Sir David Brewster's objection, Mr. Espy thought his paper it- 

 self contained an answer to it, where he showed that bodies taken 

 up on one side of the tornado, would whirl one way, and bodies 

 taken up on the other side, would whirl the other. And it was wor- 

 thy of notice, that all Col. Reid's spouts whirl from left to right, 

 and all Mr. Redfield's from right to left, on this side of the equa- 

 tor. Mr. Espy had examined a great many witnesses of the 

 Brunswick tornado, and some saw the materials which went up, 

 whirl one way, and some another, though they were standing to- 

 gether ; and Professor Strong and Professor Beck of New Bruns- 

 wick, saw the materials whirl as the hands of a watch, contrary 

 to the manner Mr. Redfield says this and all other spouts in this 

 latitude, whirl. Professor Phillips must say that he thought the 

 statements of fact connected with tornadoes, as slated in the 

 American journals, were more consistent with Mr. Espy's than 

 with Mr. Redfield's theory ; and Col. Reid thinking he saw rota- 

 tion in a water-spout could not invalidate the abiding evidence 

 from uprooted forests. 



Report of the Academy of Sciences, (Paris), on the labors of 

 J. P. ESPY, concerning Tornadoes, fyc. 



Committee, Messrs. Arago, Pouillet, Babinet reporter. 



Messrs. Arago, Pouillet, and myself, have been appointed by 

 the Academy to make a report to it upon the observations and 

 theory of Mr. Espy, which have for their object the aerial meteors 

 known by the names of storms, water-spouts and tornadoes, which 

 cause so much destruction on land and sea in the vicinity of the 

 Gulf of Mexico. These storms are produced in the same manner 

 in every part of the globe, when a few given circumstances con- 

 cur in one place. 



The labors of Mr. Espy have already considerably occupied the 

 attention of the learned world, and may be considered under three 

 different points of view. First, the facts which he has recognised 

 and substantiated, and the proofs which support them ; second, 

 the physical theory, by which he explains them and the conclu- 

 sions which he deduces from that theory ; third, the observations 

 which are yet to be made according to this theory, based upon 

 facts, and the practical rules which the mariner, the farmer, and 



