NEAR NEW nARMONT, INDIANA. O 



While the tornado was raging here, so little inconvenience was experienced five 

 miles to the north, from either wind or rain, that persons were able to continue 

 ploughing during the whole passage of the storm. This was also the case at 

 Mount Vernon, which is about the same distance, nine miles south of the axis of 

 the track. The case was similar nine miles from the axis at Golconda; little of 

 either wind or rain was experienced. 



Considering these facts, and observing, as represented in Fig. 2, that on a square 

 mile only of the track, thousands of trees, many of them having a stem at least 

 fifteen feet in circumference, lie pi^ostrated by a force operating simultaneously in 

 opposite directions; considering, also, that the time of passage of the meteor from 

 New Harmony to Leavenworth could not exceed IJ hours, and that the velocity 

 must therefore have been at least sixty miles in an hour, or one mile per minute, 

 we may form some conception of the enormous and astonishing power with which 

 this tornado, of whose presence at ten miles' distance there is not an indication, 

 passed through the atmosphere, leaving behind a desolated track of one mile in 

 breadth, on which trees, and among them the monarchs of the forest, were laid 

 low at the rate of 7,000 a minute. 



" In this vast country, where," as the Committee of the French Academy of 

 Sciences say, " enlightened men are not wanting to science, and which is, besides, 

 the home of these fearful meteors," it is surprising that a power like this should 

 not have earlier attracted the attention of scientific men ; for, according to Dr. Hare, 

 it was not until 1835, that " the immediate mechanical causes of the devastation 

 produced by tornadoes were well ascertained, by Professors Bache and Espy, from 

 observations made by means of a compass at New Brunswick." Since then, the 

 question of tornadoes has been much agitated, and it still remains a vexed one, and 

 notwithstanding the hope indulged in by several investigators of this class of phe- 

 nomena that their researches would solve the 'problem, the ultimate solution of the 

 question is as much involved in difficulty as ever. 



Before we can arrive at a satisfactory conclusion on this subject, we must first 

 ascertain if the general phenomena in tornadoes be uniform, or dissimilar. For 

 this purpose I will refer to the accounts of various tornadoes published in Silliman's 

 Journal. I shall pass by the Providence tornado, in 1838, because the observations 

 are too few in number. 



The New Haven tornado, in 1839, was examined by Professor Olmstead, who 

 considers his observations the result of better opportunities, and of more elaborate 

 and careful investigation than is usual in storms of this class; he says: "With very 

 few exceptions, the prostrations of all the trees are inwards, on both sides, to the 

 centre of the track; near the centre they coincide with the direction of the storm." 

 Out of forty prostrations which he represents on the north side of the axis, there 

 are twelve exceptions of trees lying outward from the centre ; and he says : " In a 

 few instances, in very limited spots, the prostrated bodies lie in all directions." 



The tornado at Mayfield, in Ohio, in 1842, had its track surveyed by Professor 

 Loomis, who observes that tornadoes, in addition to their progressive motion, have 

 a vertical, and two horizontal motions, one in the direction of, and the other at right 

 angles to, a radius. These four motions have a variable ratio to each other ; the 



