VOL. LIV.] PHILOSOPHICAL TRANSACTIONS. 131 



were communicated to the public in the Phil, Trans, vol. li. (Abridgment, vol. 

 xi.) As metal has been made red hot, and melted, by artificial lightning, how 

 much greater must be presumed to be the effects of the natural; and how much 

 larger ought to be the metallic part of the apparatus, to avert its mischief? This 

 requires particular attention. 



7. I was of opinion, that iron bars to support weather cocks, if they were 

 placed on the tops of buildings made of brick or stone, and in contact with 

 either of these materials, were not dangerous to ordinary buildings on the ac- 

 count you mention, except in very particular and extraordinary cases; as these 

 substances, when not much heated, conduct the electric matter in a very consi- 

 derable degree. But what lately happened to St. Bride's steeple, as well as the 

 mischief to South-Weald church on the same day, evinces that the apparatus, 

 usually applied to weather cocks, should never be trusted in any building, with- 

 out a metallic communication from them to some water, or at least very moist 

 ground. St. Bride's steeple, one of the most beautiful in London, was on Mon- 

 'day, June 18, about 10 minutes before 3 in the afternoon, very greatly injured, 

 in one of the most severe thunder storms which ever happened here. From as 

 attentive an examination, as the steeple at the present will admit of without scaf- 

 folding, it appears to me, that the weather-cock and its apparatus had the prin- 

 cipal share in occasioning the great mischief done to the upper part of the steeple. 

 I am of opinion, that the lightning first took the weather-cock, and was con- 

 ducted, without injuring the metal or any thing else, as low as where the large 

 iron bar or spindle, which is inserted into the top of the steeple, and comes 

 down several feet of its length, terminates. There the metallic communication 

 ceasing, part of the lightning exploded, cracked and shattered the obelisk, which 

 terminates the spire of the steeple, in its whole diameter, and threw off^at this 

 place several large pieces of Portland stone, of which this steeple is built. Here 

 it likewise removed a stone from its place, but not far enough to be thrown 

 down. From hence the lightning seems to have rushed upon two horizontal 

 iron bars, which are placed within the building, cross each other, to give addi- 

 tional strength to the obelisk, almost at its base, and not much above the upper 

 story : here, on the north-east and east side, it exploded again at the end of the 

 iron bar, and threw off a considerable quantity of stone. And here, for the sake 

 of explanation, I must observe, that the spire of this steeple, where it rises above 

 the bell tower, is composed of 4 stories, besides the obelisk placed over them. 

 The lowest and 2d are of the Tuscan order; the 3d is Ionic; and the 4th or 

 uppermost composite or Roman. The stone piers of these stories are connected 

 together and strengthened by iron bars placed horizontally near the height of the 

 capitals of the pilasters, and each story has only one set of these bars. From 

 the cross bars near the base of the obelisk just mentioned, the lightning broke 



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