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 being melted or otherwise injured by it; and that, great as the quantity was in this instance, and which utterly destroyed the small wire, no damage was done to the building, as far as the small wire, and the pendulum of the clock extended: and in the remarkable instance, mentioned by Mr. Kinnersley in his letter to Dr. Franklin, where a brass wire of about two lines thick, ten inches long, and terminating in a very acute point, was inserted into the iron rod, about two inches and half only of its top were melted by the lightning; the remaining part of it transmitting the lightning without being fused by it.

You will observe in this disquisition, that I have no where mentioned the apparatus attracting the lightning. l have avoided introducing the term attraction here, operating as an active principle; as I consider the apparatus purely passive, and only affording, from the aptness of its parts to that purpose, an easy and uninterrupted passage to the lightning, and thereby preventing its violent efforts.

You will pardon, Sir, this long digression in relation to St. Bride's church; as it gives so positive and explicit an answer to part of your seventh question; such a one as could not, without the late thunderstorm, have been furnished, at least from hence: To wit, that, without a proper apparatus, weather-cocks placed at the tops of any buildings are dangerous to them in thunder storms; but more especially to powder magazines.

The accidents, which have lately happened to St. Bride's and South Weald churches, if considered as great electrical experiments, furnish very important, and, I flatter myself, useful conclusions. They are too hazardous