Lippincott's Magazine, Vol. 26, August, 1880, page 189 by Various Authors
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ist. An ox stood in one corner, a cow in another and a heifer at a third, and each received a fatal stroke. On examination it was found that the rods entered the ground to the depth of only about one foot, and the soil, being dry, perfectly insulated them. Consequently, on the way to damp earth the currents jumped to the nearest conductors, which happened to be these unfortunate animals. In placing conductors it must not be forgotten that dry earth in general is not a conductor. Neither will any small quantity of surface water serve to check the rage of the electric stroke, unless there is a connection of moisture with the mass of moisture below the soil.
The depth to which lightning may penetrate before it is so dissipated as to lose its dangerous character is shown by the fulgurites, or "lightning-tubes," sometimes found in sandy soils. Their formation has been conclusively traced to disruptive electrical discharges from the clouds, which have melted the sand by the intense heat generated in passing through to a moist earth. These tubes generally divide into prongs, like a parsnip, as they descend. The inner surface is smooth and very bright. It scratches glass and strikes fire as a flint. They are sometimes found three inches in external diameter, and extending to a depth of thirty feet. In one instance five of these tubes were found in a single hill.
This tendency of certain localities to receive the electrical discharge is further illustrated by the number of times certain buildings in every considerable town have been struck. As before stated, the elevation of the structure does not seem to be the determining influence in directing the stroke, for the unfortunate edifice often stands much lower than some others in the vicinity which have always been struck. Numerous illustrations of this can be found in the records of European countries. Hollis Street Church in Boston has been struck several times, though the ground on which it stands is but little above the level of the sea, while the State-H