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ring it to the fact of the discharge taking place at a great altitude, and 

 consequently in comparatively rarefied air, as in the case of the co- 

 lour exhibited by the spark through a vessel partially exhausted. 



The storm of the evening of the 14th of July, was said to be more 

 severe than any which had visited Princeton for twenty years before. 

 It commenced between 7 and 8 o'clock, and lasted about three hours ; 

 the thunder was almost continuous, but, except in two or three cases, 

 it was not very near. Several buildings and other objects were 

 struck in the vicinity of Princeton, and also Mrs. Hamilton's house, 

 which is situated in the village, about 20 rods west of the college, on 

 the opposite side of the way. It seemed a little surprising that this 

 house should be singled out, since the buildings on either side are 

 considerably higher, although at a few rods distance ; and in front of 

 the one to the west is a number of tall trees. The house is also fur- 

 nished with a lightning rod; but this, like most of the rods erected in 

 the country, is not formed in accordance with the most scientific prin- 

 ciples. The front of Mrs. Hamilton's house is parallel with the main 

 street, and is nearly in an east and west direction. The building is 

 of brick, with a shingle roof, and two stories high : it has on the front 

 three upper windows, and two windows and a door below; the latter 

 being immediately under the western upper window. The chimney 

 is on the eastern end, and the lightning conductor is supported 

 against this. The rod is formed of round iron, three-eighths of an 

 inch thick, and the several parts of it are imperfectly connected by 

 hooks and eyes. It appears to be merely thrust into the ground to 

 the depth of about two feet, and is terminated above by three prongs 

 instead of one ; the points of which are blunted by long exposure, but 

 do not exhibit any appearance of fusion. The top of the rod is not 

 more than six feet above the ridge of the roof; and since the house is 

 about thirty feet long, the farther end of the ridge is unprotected. A 

 point, according to the experiments of Mr. Charles, can only protect 

 a circular space, the radius of which is not greater than twice the 

 height of the point above the plane to be protected. 



The lightning, according to the accounts of several persons, came 

 from a cloud situated to the south-west, and the discharge did not 

 strike the most elevated part of the building, but the western end of 

 the horizontal wooden gutter which extends along the front of the 

 house under the eaves. This point is at the greatest possible distance 

 from the extremity of the lightning rod, and perhaps as near to the 

 cloud as any other part of the building. The discharge immediately 

 divided itself into two parts : one of these, and probably the larger, 



