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XLI. An Account of some Thunder-storms and extraordinary 

 Electrical Phenomena that occurred in the neighbourhood of 

 Manchester on Tuesday the 16th of July 1850. By Peter 

 Clare, F.R.A.S., Vice-President of the Literary and Phi- 

 losophical Society of Manchester*. 



[With a Plate.] 



ON the 16th of July in the present year several severe 

 storms of thunder, lightning, hail and rain, attended 

 with fatal results, occurred in the southern part of Lancashire 

 and northern part of Cheshire, which were succeeded by some 

 very extraordinary electrical appearances, such as I do not 

 remember to have previously noticed, although I have been 

 an attentive observer of electrical discharges in the atmosphere 

 for more than half a century. 



These storms, with one exception (which occurred in Der- 

 byshire), appear to have originated in different localities, 

 within a range of fifty miles from north to south, and forty 

 miles from east to west; extending from the river Ribble 

 below Preston in the north to the neighbourhood of Nantwich 

 in the south, and from the course of the river Irwell near 

 Bury in the east, to North Meols in the west. 



For several days previous to that on which the storms oc- 

 curred, the weather had been generally very fine, the barometer 

 varying only from 30*15 inches to 30 inches, giving a mean 

 for the three preceding days of 30*07 inches. The thermo- 

 meter for the same period, at eight o'clock in the morning, 

 varied from 65 to 67 degrees of Fahrenheit; at two o'clock p.m., 

 from 77 to 79 degrees ; and at ten o'clock in the evening, 

 from 65 to 69 degrees, giving a mean for the four days of 

 70*33 degrees ; whilst during the same period the wind near 

 the earth blew from the north, or north-north-east, and the 

 clouds during the whole time moved from east to west. 



On the morning of the 16th, previous to the commencement 

 of the storms, the weather was very fine at Manchester, with 

 some thin clouds floating in the atmosphere ; but as the day 

 advanced the clouds became more dense, although the pressure 

 of the air did not vary more than the one-hundredth part of 

 an inch from eight o'clock in the morning until ten o'clock in 

 the evening. About two o'clock in the afternoon some dark 

 clouds had formed in the north and east, and afterwards ex- 

 tended towards the west; at four o'clock those in the north- 

 west had become much more dense and dark, and one or two 

 distant peals of thunder were heard in that direction, but with- 



* Communicated by the Author; having been read to the Literary and 

 Philosophical Society, October 1, 1850. 



