Page:Philosophical Transactions - Volume 054.pdf/278

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as the rain begins, and falls upon so much of the apparatus, as is placed in the open air, the bells of the apparatus in the house ring, and the electrical snaps succeed each other in a very extraordinary manner. This demonstrates, that every drop of rain brings down part of the electric matter of a thunder cloud, and dissipates it in the earth and water; and prevents thereby the mischiefs of its violent and sudden explosion. Hence, when the heavens have a menacing appearance, a shower of rain is much to he wished for.

From these considerations, I have no doubt, but that the mischief done to St. Bride's steeple was owing to the efforts of the lightning, after it had possessed the apparatus of the weathercock, endeavouring to force itself a passage from thence to the iron work, employed in the steeple. As this must be done per saltum, there being no regular metallic communication, it is no wonder, when its force is vehement, that it rends every thing which is not metallic, that obstructs its easy passage; and in this particular instance, the ravages increased as the lightning to a certain distance came down the steeple. To procure this easy passage and avert the ravage occasioned by the want of it, in future, as much as our present knowledge in these matters will enable us to do, I cannot sufficiently recommend metallic communications between the metal at the top and water, either as has been before mentioned, or in any other convenient manner, taking care not to be too frugal of the metal employed. This was first suggested by that excellent Philosopher Dr. Franklin; and since much used in Philadelphia, and other parts of North America.

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