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 taken down several feet of its length, and properly repaired. This ought to be a caution to succeeding builders, that if, in ediﬁces of this kind, they ﬁnd it expedient to employ cramps, they should be either of copper, which is not liable to swell by moisture; or, if iron be used, so much space should be left in the under bed of the stones, which immediately cover the cramps, that they may have room to extend themselves without danger to the building. This remark, though not immediately relating to our present purpose, will not, I hope, be thought impertinent in this place.

But to return: this thunder storm had been preceded by several very warm days. The nights had scarce furnished any dew: the air was quite dry, and in a state perfectly unfit to part with its highly-accumulated electricity without violent efforts. This great dryness made the stones of St. Bride's steeple, and all other buildings under the like circumstances, far less fit than if they had been in a moist state, to conduct the lightning, and prevent the mischief. For though this thunder storm ended in a heavy shower of rain, none except a few very large drops fell till after the church was struck; and I have no doubt, but that the succeeding rain prevented many accidents of a similar kind, by bringing down with every drop of it part of the electric matter; and thereby restoring the equilibrium between the earth and clouds. It is frequently taken notice of, in attending to the apparatus for observing the electricity of the clouds, that tho' the sky is much darkened, and there have been several claps of thunder at no great distance, yet the apparatus will be scarce affected by it; but as soon