Tornado in N. E. part of Ohio, Feb. 4, 1842: 297 



contrary to the sun's motion ; moved towards the northeast. 

 Aug. 3, 1839, several sand whirls formed in the road, moved but 

 a short distance, yet all revolved in the same direction with the 

 sun's motion. Aug. 4, 1839, another revolved in the same direc- 

 tion. May 8, 1840, a whirl revolved in the opposite direction. 

 Having satisfied myself that these small whirls revolve indiffer- 

 ently with or against the sun, I took no further pains to record 

 particular dates, but have since often observed them revolve in 

 each direction. 



In all the preceding cases, including those of Stow and May- 

 field, there are two distinct motions — first the progiessive motion 

 of the meteor, and secondly its own peculiar motion ; and this 

 last may be resolved into three others, viz. a vertical motion, and 

 two horizontal, one in the direction of a radius, and the other at 

 right angles to it. These four motions appear to bear a variable 

 ratio to each other. The upward and centripetal motions no 

 where disappear, yet they are seen in very unequal strength at 

 Mayfield and Painesville ; while the motion at right angles to a 

 radius is strongly marked at Mayfield, but barely distinguishable at 

 Stow. By pursuing the method of investigation exemplified in 

 this article, it is believed that the peculiarities of a well marked 

 tornado can hardly escape detection. May we not then indulge 

 the hope that the much ve'xed question, whether tornadoes are 

 whirlwinds, will soon be settled ? That some tornadoes are whirl- 

 winds certainly cannot be denied. That the motion at right an- 

 gles to a radius is sometimes quite small compared with the cen- 

 tripetal motion, seems equally clear. That this motion in a tor- 

 nado should ever become mathematically nothing, appears infin- 

 itely improbable. 



I have collected below, in a tabular form, all the tornadoes in 

 this country with respect to which I have been able to obtain 

 any important information, and have introduced some of which 

 I could only furnish the dates. It is hoped that those who have 

 the means will contribute to filling these blanks. 



Vol. xLin, No. 2.— July-Sept. 1842. 38 



