GRISCOM ON METEOROLOGICAL OBSERVATIONS. 3f>3 



„&s the circumstances of the observer will admit. It would likewise be 

 proper to remark the first or earliest visits of the swallow, martin, and 

 other birds, and likewise those of some of the aquatic tribes, as the 

 mackerel, shad, &c. 



Information of this kind would probably afford, to persons at a dis- 

 tance, more correct data, from which they might draw conclusions with 

 respect to the nature of our climate, than the best register of the 

 weather, and of the instruments which denote its temperature and its 

 changes. 



Extract of a letter dated Cincinnati, November 9, 1 81 4, from Dr. N. 

 Crookshank to Dr. Peter Wilson, Columbia College. 



" On the 4th of June last, about meridian, a dark cloud appeared in 

 or near the southwest point of the horizon, having the usual appear- 

 ances of electricity, as was known, by the hemispherical or convex 

 appearances of various parts on the superior sides of the different 

 shelves composing it ; while the lower part appeared parallel to the 

 earth. Some light clouds were seen to move with great rapidity from 

 the northeast, and appeared to meet the former; when both seemed to 

 rise perpendicularly several degrees, so as to attain an extraordinary 

 height. I then predicted hail, which presently fell, of uncommon size. 

 Several were picked up after the shower, which ended in rain, too 

 large to put into a cup four inches in diameter. Others were picked 

 up in the time of the fall, thirteen, fourteen, and even fifteen, inches in 

 circumference : yet, strange to tell, no material damage was done, 

 though the width of the shower was five miles, and twenty or thirty in 

 length; the tract of the largest hail, in centre of the former, about a 

 mile. It appeared to consist of several clouds detached from each 



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