Electrical and Other Properties of Sand ¹

Abstract

THIS material, which flows so freely through my fingers and may be poured in the manner of a liquid Irom one vessel to another, is common sand. Specimens from various parts of the world are here exhibited; there are sands from the Sahara Desert, from New Zealand, France, Scotland, and several parts of England. There are also bottles of the coloured sands from Alum Bay, in the Isle of Wight, and Redhill. It may be pointed out at once. that this coloration is merely due to the presence of an adherent layer of oxides or hydroxide of iron, for even varieties which appear under the microscope to contain little or no coloured particles generally have a trace of iron clinging to the grains.