Luftelektrizität

Abstract

THIS is one of a long series of cheap, instructive books published by the firm of G. J. Göschen. The principal contents are the earth's potential gradient, forty-four pages; the electric conductivity of the atmosphere, thirty-five pages; electric currents in the air (including the ordinary fair-weather vertical current, electricity brought down by rain and snow, and lightning), twenty-nine pages; and the radio-active phenomena of the atmosphere, twenty-eight pages. Two other shorter sections deal respectively with the electric effects of sunshine and theories as to the source of atmospheric electricity. There are eighteen figures in the text, including some interesting Potsdam records of potential gradient during calm and disturbed weather. The author is a member of the staff of the Royal Meteorological-Magnetic Observatory at Potsdam, and is a recognised expert on the subject of which he treats. Considering its size, the book gives an excellent account, clear as well as concise, of the whole subject. German results loom somewhat more largely than they probably would in a text-book written in France or England, but there are a good many references to non-German writers, including Chauveau, Simpson, and C. T. R. Wilson.