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New Zealand Graphic, Volume XLI, Issue 9, 26 August 1908, Page 36

The formation of hail through electrical action, according to the new theory of scientists attached l to the Weather Bureau at Washington, is an interesting and even wonderful process. The wind draws out a cloud into a long, narrow strip. In that form, owing to the great amount of surface, the cloud evaporates rapidly, and the rapid evaporation pro-

duces intense cold. Dry particles of snow are then formed, and these, by friction with the water drops, quickly become charged with negative electricity. But the water drops themselves carry positive electricity, and since negative attracts positive, a film of water is formed! upon each snow particle, and is instantly frozen into a layer of ice. At this thickness its outer surface remains moist, the water not freezing there so rapidly, whereupon the electrical charge changes from negative to positive, and the particle is repelled by the water drops and driven to the outer parts of the cloud. Here the increased cold! covers it with snow again, and the friction charges it anew with negative electricity. Repulsion is now once more changed for attraction, and the particles rush back into the cloud, receiving upon their surfaces another film of water, which is turned into second ice layers. Thus the growing hailstone darts zigzag through the clouds, piling up its alternate layers of snow and ice until gravitation gains control, and sends it. with a jingling crowd of its fellows, spin ring to the ground.—“ Science Siftings.’