340 Observations on the New Haven Tornado. 



Art, XXIL — Observations on the New Haven Tornado of July 

 31, 1839 ; by Denison Olmsted, Professor of Natural Philoso- 

 phy and Astronomy in Yale College. 



On the 31st of July, 1839, there occurred, on the western 

 skirts of the city of New Haven, a tornado of the most violent 

 class. The preceding morning had been cloudy and sultry, and 

 immediately previous to the tornado, a thunder storm seemed 

 approaching from the west, attended by some appearances of 

 high wind. I was, at the time, about a mile eastward of the 

 track of the storm, observing the phenomena from my chamber 

 window. The clouds betrayed that singular agitation, which 

 usually forebodes a hurricane, and the vane of a neighboring 

 steeple was constantly shifting its position. A short time before 

 the tornado commenced, the wind blew fresh from the southeast, 

 having been in this quarter during the preceding morning ; it 

 changed suddenly to the south, and in a moment more it was 

 west, where it continued fixed. Accompanying these changes a 

 heavy rumbling noise was heard, not unlike the passing of a long 

 train of railway cars, which was audible in every part of the city. 



Such were the only facts of importance which I had an oppor- 

 tunity of observing at the time ; but the circumstances have 

 proved unusually favorable for investigating the laws of the storm, 

 occurring as it did at mid-day, and so near to us that we have 

 been able to repeat our examinations of the grounds a number of 

 times. Among those included within the limits of the tornado, 

 were several accurate and intelligent observers, who remarked 

 the phenomena with much attention ; and even those who were 

 buried beneath the ruins of their houses, have all survived to tell 

 their story. In addition to these peculiar opportunities for ascer- 

 taining the facts respecting the storm, I have had the still greater 

 advantage of comparing my owu observations with those of my 

 friends, Professor Stanley, Mr. A. B. Haile, and Mr. E. C. Herrick, 

 all of whom have taken the greatest pains to investigate the phe- 

 nomena and laws of the tornado. Hence the facts which I have 

 to state, are, I think-, the result of better opportunities for obser- 

 vation, and of a more elaborate and careful examination, than 

 has been usual in storms of this class. 



