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 nails, and other metallic substances to have been melted, and parts of them, while hot, bedding themselves in wood, by a thunder storm. Of this we had some instances here in a thunder storm, which happened in July 1759, of which the effects were communicated to the public in the Philosophical Transactions. 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 mifchief? This requires particular attention.

VII. I was of opinion, that iron bars to support weather cocks, if they were placed upon 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 account you mention, except in very particular and extraordinary cases; as these substances, when not much heated, conduct the electric matter in a very considerable degree. But what lately happened to St. Bride's Steeple, as well as the mischief to South-Weald church on the same day, evinces, to me at least, that the apparatus, usually applied to weather cocks, should never be trusted in any building, without 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 Monday, June 18, about ten minutes before three 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 scaffolding, it

LIV.