Page:Philosophical Transactions - Volume 054.pdf/288

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fully the necesity of preventing the danger, that such buildings are exposed to.

The construction of the spire is somewhat similar to that of an apparatus purposely contrived to draw the lightning from the clouds, as it runs up towards a point, and ends in a metal vane and cross, the figure of which, as well as the materials that they consist of, seem calculated to admit the lightning with the least resistance.

At this place the first marks of it are seen: at H the top of the copper cross, which is the highest part of the building, the gilding is by the explosion partly torn off and partly discoloured, so as to differ remarkably from the rest of the cross where the gilding is very well preserved. Some small pieces of solder are melted; and all this part appears as if it had been exposed to the fire.

The lightning seems to have entered here, and to have been conducted as low as the hole at A, by an iron spindle twenty feet in length, and two inches in diameter; of which ten feet were surrounded by the copper ball, vane and cross; and the lower half was inclosed in a groove cut through the middle of the solid stones which composed the upper part of the spire, and rested at A on the bottom of that groove, which was sunk five inches deep into the lowest of those solid stones: this last mentioned stone being three feet broad and one deep. The interval between the sides of the spindle and the groove made to receive it was filled up by melted lead poured in between them.

The lightning accumulated in the metal, having it’s passage towards the earth strongly resisted at this place, has in expanding itself formed the hole A, by

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