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The majority of the manufacturers increase the size of the conductors for high buildings—one making the limit 120 feet, another 150 feet, while a third “varies the sectional area with the length.” One firm does not consider any difference necessary, while another takes it that the sectional area should be the same irrespective of length, for “lightning does not vary in intensity while passing through a conductor of greater or less length.”

Now, the laws of electricity clearly show that to maintain equal efficiency we must vary the sectional area as we increase the length of the conductor; but it is a question for the Conference to decide whether we should not recommend a rope of uniform dimensions that would be equally applicable for high and low buildings. Within ordinary limits the necessity for increased thickness for increased height is scarcely evident, but the remedy of an increased sectional area, with the number of separate points erected, is very clear. Indeed, each point should be the terminal of a conductor, whose sectional area should be uniform to the earth. For if it be not so, and each conductor be fully charged with electricity, then when the sectional area diminishes there will be congestion, resulting in heat and discharge to the building. Hence the thickness of the main conductor must increase with the number of separate points erected.