Ampere, the Etherians, and the Oersted Connexion

IN 1826 Andre-Marie Ampere published the 'Mathematical theory of electrodynamic phenomena, uniquely derived from experiment', in which he showed how the mathematical law for the force between current elements could be derived from four ingenious equilibrium experiments. He made a great show of following a Newtonian inductivist methodology, and his law, like Newton's for gravitation, was presented as a purely descriptive mathematical expression for a certain class of phenomena, one for which its author did not provide any causal or ontological justification. Ampere's electrodynamics would accordingly seem to have been a solid contribution to the Laplacian-Newtonian approach to physics so actively pursued in France during the first quarter of the nineteenth century. It does not surprise us to read that his electrodynamic force law and his molecular-currents theory of magnetism were immediately and widely accepted by his French contemporaries. Ampere was, in this view, just another of the many great French mathematical physicists of the period

Review of Klaus Bonik et al., Materialistische Wissenschaftsgeschichte: Naturtheorie und Entwicklungsdenken, ed. Helmut Bien et al.

A book review of Klaus Bonik et al., Materialistische Wissenschaftsgeschichte: Naturtheorie und Entwicklungsdenken, ed. Helmut Bien et al. ("Argument-Sonderband," AS 54; Berlin: Argument-Verlag, 1981

Review of Enrico Bellone, A World on Paper: Studies on the Second Scientific Revolution,

A book review of Enrico Bellone, A World on Paper: Studies on the Second Scientific Revolution, translated by Mirella and Riccardo Giacconi (Cambridge: The MIT Press, 1980

Colding, Ørsted, and the Meanings of Force

THE DANISH PHYSICIST and engineer Ludvig August Colding (1815-1888) is known to historians of nineteenth-century physics as the author of one of several formulations, during the 1840s, of the concept that eventually gained currency as the principle of the conservation of energy. Thanks largely to the work of Per Dahl, the substance of Colding's work and a rough idea of the route he followed has been known for several decades.1 In brief, Colding sought experimental corroboration, in terms of the frictional heat produced via the expenditure of a measured amount of mechanical work, of a rough notion of the general imperishability of the forces of nature that he derived from an originally metaphysical conviction concerning the imperishability of the human spirit regarded as a species of force. Nor has the importance gone unnoticed of (Holding's relationship to Hans Christian Ørsted (1777-1851), to whom Colding was attached for many years as student and protégé Ørsted had disclosed the interactive relationship between electricity and magnetism in 1820 and was a highly visible proponent of the notion of the unity of nature, as showcased in particular in the collection of essays he entitled The spirit in nature? Yet some of the important details in this overall picture remain unclear. The quality of Colding's metaphysical beliefs has not been explored in appropriate depth, nor has the significance been established of his brief reference to the role played in the development of his ideas by the antimateri alistic pronouncements of zoologist and physiologist Daniel Frederik Eschricht (1798-1863).3 Nor have we been adequately enlightened as to the significance of what he referred to as d'Alembert's principle of lost forces, or to the status of such a principle in the mechanics of the period.4 And his relationship to Ørsted is problematic. Although there would appear to be some important con nection between Colding's and Ørsted's general views on nature and its forces, and Ørsted occasionally asserted some kind of unity among the forces of nature, he failed signally to appreciate the significance of Colding's work when it was given him to evaluate.5 The solution to this apparent paradox will be sought through an understanding of Ørsted's changing conception of force and its relationship to the "activities" of heat, light, electricity, magnetism, and chemical activity.6 Without paying proper attention to language, historians have tended to read back into Ørsted's usages meanings of "force" that came to it in large part as a result of the work of Colding and his generation.

Review of Stephen G. Brush, ed., History of Physics: Selected Reprints (College Park, Md.: American Association of Physics Teachers, 1988

A book review of Stephen G. Brush, ed., History of Physics: Selected Reprints (College Park, Md.: American Association of Physics Teachers, 198

From Galvanism to Electrodynamics: The Transformation of German Physics and Its Social Context

Historians have long been aware that German science underwent a profound qualitative and quantitative transformation during the first half of the nineteenth century. This paper investigates the qualitative aspects of that change in a single field of study, electricity and mag netism. Because this area of physical research was more actively pur sued, and pursued by a greater number of individuals, than any other, it may reasonably serve as a first approximation to the state of affairs in other areas of physics as well. Only future research will indicate whether certain generalizations based on this study depend upon factors peculiar to research in electricity and magnetism