John TyndaFs Researches on Magnetism

Abstract

The author demonstrates the following three theses in this paper. 1.In his works in 1850s John Tyndall tried to explain the deportments of magnetic and diamagnetic substances in magnetic fields from the viewpoint of action-at-a-distance theories, which were then prevalent on the Continent and had established their own tradition as different from that of field theories. It was, however, in an attempt to provide an alternative theory to Plticker's which was itself an action-at-a-distance theory, rather than to oppose the field theories, that Tyndall carried out his experimental investigations, at first in collaboration with Knoblauch. 2. Tyndall's researches on magnetism were guided by his conception of matter which conceived magnetic and diamagnetic substances, and eventually all substances, as consisted of minute particles. 3. Tyndall's approach to magnetic phenomena as well as his particulate conception of matter were established under the influence of the works by Knoblauch and de Senarmont on the anisotropic features of various substances.