I Fenomeni Magnetici Nelle Varie Teorie Elettro-Magnetiche

Abstract

THE scope of this interesting little volume, by an Italian author, is novel to English readers; at least, the present writer cannot recollect any other book devoted entirely to the history of the theory of magnetism. Oersted's fundamental discovery that an electric current gives rise to a magnetic field in surrounding space was important, not only as the starting point of electro-magnetism, but also because, in the hands of Ampere, it became the basis of a theory designed to explain the physical nature of magnetism. Beginning at this point, the author passes in review the work of Poisson; Faraday's conception of lines of force, with its necessary recognition of the part played by the medium; the successful development of this idea in mathematical form by Maxwell; the theories of Weber and Ewing; the experimental work of Curie on diamagnetic and feebly magnetic substances; and finally, the modern electronic theory of magnetism as extended by Langevin, Weiss, Gans, and others. The various stages in the historical development are clearly displayed, and, although more elementary in its treatment, the book is a worthy companion of Whittaker's well-known “History of the Theories of Elasticity and the Ether.” An English volume of similar scope would be a very desirable addition to current text-books.

I Fenomeni Magnetici Nelle Varie Teorie Elettro-Magnetiche.

Note Storico-Critiche. By Silvio Magrini. Pp. 165. (Bologna: Nicola Zanichelli, 1912.)