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 II. This method, wherever it has been employed, has hitherto perfectly answered the intention; no house in Philadelphia, or in any other place I have heard of, having suffered from the effects of lightning, where this apparatus has been erected. The improvements I should recommend would be, first; that, as iron wire soon becomes rusty, and when rusty to the center is unfit for the present purpose; and as brass wire is, when long exposed to the weather, exceedingly brittle and liable to snap asunder, the wire should be of copper; and of a size not less than that of a large goose quill. Secondly, I prefer it's being conducted, from the rod at the top to the water below, on the outside of the building, and thereby prevent the lightning from coming within the building. On houses, where there are gutters and spouts of lead to carry off the rain, the wire need only be conducted to the lead of the gutters; and attention be had that the gutters and the spouts coming from them are in their whole length in contact, or very nearly so, one with the other. If the leaden spouts do not reach to the bottom of the building, a slip of lead, such as is employed for the gutters, and about an inch wide, should be fastened to the bottom of one or two of the spouts, and conducted to the water. If a slip of lead, such a one as has just been mentioned, was to be conducted from the rod at top to the gutters, it might with equal advantage be substituted for the copper wire: or further, a slip of lead of this kind may be connected with the rod at the top of the house; and, where there are no leaden gutters or spouts, may be conducted on the outside of the house down to the water, as I before