SummaryThe present paper deals with the determination of the size and charge of a single submicroscopic particle, measured in a small horizontal condenser of a diameter of approximately 8 mm., using the author's method first stated April 1910. To obtain the highest sensitivity, author used solid particles of an order of magnitude under 3 × 10–5 cm. and found charges less than that of the electron. Various objections were raised against his findings, namely that the particles investigated were not spheres, (...) and that their density was not that of the macroscopic substance, so that his findings of charges less than the electronic charge were merely imaginary. The author has succeeded in precipitating and measuring a particle after having observed it in the condenser under normal and also very high gas pressures. The particles were shown to be perfect spheres. A new method is indicated whereby it is possible to determine the size of sub-microscopic spheres by pushing together two equal spheres with a micromanipulator; the two diffraction disks overlap and render it very easy to determine the actual size. It is also possible to show that the density of each individual sphere is that of the macroscopic substance, since it can be computed easily from the velocity of fall at high gas pressures. These two data being accurately determined, the author still found charges considerably less than the electronic charge, and the deviations are too great to be accounted for by errors of observation. The reason that the author has used a solid substance and not oil, which is a liquid, was in the first place, that liquids evaporate, and therefore do not yield correct results, and secondly, because liquid spheres are not certain to preserve their sphericity when precipitated. Thus charges less than that of the electron are to be considered as actually existing. (shrink)

According to generally accepted views every material body has always just as much North as South magnetism, meaning that the total value of the North and South magnetism is always zero. One says therefore that there is no “true magnetism”. A body directs itself in the direction of the magnetic lines of force like a compass needle but it does not move from its place. On the other hand, it is known that there are electrically charged bodies which move in (...) homogeneous electric fields along the lines of force. There is thus a preponderance of positive or negative electricity on ions. One says also that there exists “true electricity”. A movement of charged matter in a homogeneous field is called a current. Consequently until now electric currents were known to exist, but no magnetic currents. (shrink)

This paper introduces and reproduces a document from Feyerabend’s Nachlass including: (i) Feyerabend’s 1967 tentative translation into English of an original German typescript reporting the lecture notes of an academic course on magnetic monopoles delivered by physicist Felix Ehrenhaft (1879-1952) at the University of Vienna in the 1947 summer semester; and (ii) Feyerabend’s memoir focusing on Ehrenhaft in postwar Vienna.In addition to making available to a larger audience Ehrenhaft’s lectures on a highly controversial topic, the publication of (...) Feyerabend’s typescript offers the opportunity to reconsider, delve deeper into and cast a brighter light on a rather neglected aspect in the growing literature on Feyerabend’s thought: the significance of Ehrenhaft for the development of Feyerabend’s intellectual biography. (shrink)

No study in the philosophy of science created such controversy in the seventies as Paul Feyerabend's Against Method. In this work, Feyerabend reviews that controversy, and extends his critique beyond the problem of scientific rules and methods, to the social function and direction of science today. In the first part of the book, he launches a sustained and irreverent attack on the prestige of science in the West. The lofty authority of the "expert" claimed by scientists is, he argues, incompatible (...) with any genuine democracy, and often merely serves to conceal entrenched prejudices and divided opinions with the scientific community itself. Feyerabend insists that these can and should be subjected to the arbitration of the lay population, whose closes interests they constantly affect—as struggles over atomic energy programs so powerfully attest. Calling for far greater diversity in the content of education to facilitate democratic decisions over such issues, Feyerabend recounts the origin and development of his own ideas—successively engaged by Brecht, Ehrenhaft, Popper, Mill and Lakatos—in a spirited intellectual self-portrait. Science in a Free Society is a striking intervention into one of the most topical debates in contemporary culture and politics. (shrink)

Acceptance of the quantization of the elementary electrical charge was preceded by a bitter dispute between Robert Millikan and Felix Ehrenhaft, which lasted for many years. Both Millikan and Ehrenhaft obtained very similar experimental results and yet Millikan was led to formulate the elementary electrical charge and Ehrenhaft to fractional charges. There have been four major attempts to reconstruct the historical events that led to the controversy: Holton ; Franklin ; Barnes et al. ; Goodstein. So we (...) have the controversy not only among the original protagonists but also among those who have interpreted the experiment. The objective of this study is a critical appraisal of the four interpretations and an attempt to provide closure to the controversy. It is plausible to suggest that Ehrenhaft's methodology approximated the traditional scientific method, which did not allow him to discard anomalous data. Millikan, on the other hand, in his publications espoused the scientific method but in private was fully aware of the dilemma faced and was forced to select data to uphold his presuppositions. A closure to the controversy is possible if we recognize that Millikan's data selection procedure depended primarily on his commitment to his presuppositions. Franklin's finding that the selection of the drops did not change the value of e but only its statistical error carries little weight as Millikan did not perform Franklin-style analyses that could have justified the exclusion of drops. It is plausible to suggest that had Millikan performed such analyses, he would have included them in his publication in order to provide support for his data selection procedures. In the absence of his presuppositions, Millikan could not tell which was the ‘expected correct’ value of e and the degree of statistical error. Finally, if we try to understand Millikan's handling of data with no reference to his presuppositions, then some degree of ‘misconduct’ can be perceived. Introduction An appraisal of Holton's interpretation An appraisal of Franklin's interpretation An appraisal of Barnes, Bloor and Henry's interpretation An appraisal of Goodstein's interpretation A crucial test: the second drop of 15 March 1912 Conclusion: Is closure possible? (shrink)