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The Case of Atwood's Machine

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The Case of Atwood's Machine Advances in Historical Studies 2014. Vol.3, No.1, 68-81 Published Online February 2014 in SciRes (http://www.scirp.org/journal/ahs) http://dx.doi.org/10.4236/ahs.2014.31007 Spreading Newtonian Philosophy with Instruments: The Case of Atwood’s Machine Salvatore Esposito1, Edvige Schettino2 1I.N.F.N., Naples Unit, Naples, Italy 2Department of Physics, University of Naples “Federico II”, Naples, Italy Email: [email protected], [email protected] Received June 13th, 2013; revised July 20th, 2013; accepted July 29th, 2013 Copyright © 2014 Salvatore Esposito, Edvige Schettino. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. In accordance of the Creative Commons Attribution Li- cense all Copyrights © 2014 are reserved for SCIRP and the owner of the intellectual property Salvatore Esposito, Edvige Schettino. All Copyright © 2014 are guarded by law and by SCIRP as a guardian. We study how the paradigm of Newton’s science, based on the organization of scientific knowledge as a series of mathematical laws, was definitively accepted in science courses—in the last decades of the XVIII century, in England as well as in the Continent—by means of the “universal” dynamical machine invented by George Atwood in late 1770s just for this purpose. The spreading of such machine, occurring well before the appearance of Atwood’s treatise where he described the novel machine and the experi- ments to be performed with it, is a quite interesting historical case, which we consider in some detail. In particular, we focus on the “improvement” introduced by the Italian Giuseppe Saverio Poli and the sub- sequent “simplifications” of the machine, underlying the ongoing change of perspective after the defini- tive success of Newtonianism. The case studied here allows recognizing the relevant role played by a properly devised instrument in the acceptance of a new paradigm by non-erudite scholars, in addition to the traditional ways involving erudite scientists, and thus the complementary role of machine philosophy with respect to mathematical, philosophical or even physical reasoning. Keywords: Atwood’s Machine; Giuseppe Saverio Poli; Newtonianism Introduction semination extended well beyond his lectures and publications. Indeed, for example, in 1715 Desaguliers also performed ex- The XVIII century was characterized by a widespread inter- periments on colors before members of the French Académie est for natural philosophy, driven by public lecture courses and Royale des Sciences, thus paving the way to a wider recogni- the publication of popular texts in addition to the traditional tion of the validity of Newtons theories in France, and much the forms of transmission of knowledge. The scientific societies same took place before diplomatic audiences from Spain, Sicily, and academies created during the scientific revolution played Venice and Russia (Stewart, 1992). The Dutch Willem Jacob’s an increasingly larger role than universities, thus becoming the Gravesande was present to the demonstration of 1715, and later cornerstone of organized science (McClellan, 2003; Gillispie, became a decisive spokesman of Newtonian science in the 1980). In England, the presidency of Sir Isaac Newton to the Netherlands, a country which already played in the XVII cen- Royal Society from 1703 to his death in 1727 obviously led tury a significant role in the advancement of the sciences, in- British science to be dominated by Newtonian ideas and ex- cluding Isaac Beeckman’s mechanical philosophy and Chris- periments, and the structure itself of Newtonian physics, that is tiaan Huygens’ work on the calculus and in astronomy (Jacob, scientific knowledge organized as a series of mathematical laws, 1988). The Netherlands became the first Continental country to became the model for all sciences. However, due to this use of adopt Newtonianism, with Amsterdam becoming the center of mathematics, very few people—in England and abroad—were European publishing, thanks, again, to French exiles, while in able to understand Newton’s ideas, so that an army of popular- France the struggle against Cartesianism lasted for some time, izers, lecturers and textbook writers was required in order to the Newtonianism attracting mainly people dissatisfied with widespread Newtonianism: this occurred precisely in the early French society and the Catholic Church, like Voltaire. A similar, XVIII century, continuing for about half a century. or even deeper struggle, was fought in the Germanic world, The rapid dissemination of Newton’s science came first via where Newton’s science contended against the prestige of the members of the Royal Society, both British and Continental Leibniz’s philosophy, this resulting in the long-lasting Newto- (Feingold, 2004), and an important role was played by Hugue- nian-Wolffian controversy (Calinger, 1969): in the XVIII cen- nots (Baillon, 2004; see also Gibbs, 1986), i.e. French Protes- tury, Germany was always hesitant about the mechanization of tants who had been expelled from France as early as 1685. In nature, and eventually Newton’s mechanics was incorporated this respect, a key contributor to the success of Newtonian sci- into the dominant German academic philosophy. Instead, New- ence was John Theophilus Desaguliers, whose work of dis- ton’s science filtered quite early into different parts of Italy, 68 Open Access S. ESPOSITO, E. SCHETTINO notwithstanding the Inquisition looked with suspicion on these tions” underlying the ongoing change of perspective are pointed ideas, not least because they came from a Protestant country. out as well. Finally, in the concluding section, we summarize The traditional way to disseminate Newtonian natural phi- what discussed in order to provide a rapid overview of the his- losophy was, of course, through academic courses: before the torical case studied. XVIII century, indeed, science courses were taught almost ex- clusively through formal lectures. Thus, in the first instance, Newtonian Textbooks of Natural Philosophy in scientists, mathematicians and philosophers of Holland, France, the Post-Newtonian Age Germany and Italy read Newton’s books and taught the ideas to their students. The structure of courses, however, began to Newtonian doctrines spread in the first quarter of the XVIII change in the first decades of the XVIII century, when physical century thanks to elementary or complex textbooks by English demonstrations were added to academic lectures, and popular authors such as J. T. Desaguliers, or the Dutch ones W. J. ‘s lectures were introduced in response to the growing demand for Gravesande and Pieter van Musschenbroek, and the Frenchman science. For example, Pierre Polinière was among the first indi- Jean Antoine Nollet. The complexity of Newtonian thought viduals to provide demonstrations of physical principles in the expressed itself in several different ways, and in the following classroom: he presented experimental demonstrations of his we will give a glimpse of such diversity. own devising before students at the University of Paris (Hanna, 1972), his lectures proving so popular that in 1722 he presented Newton’s Experimenter Successor a series of experiments before Louis XV, King of France. In The first English disciples of Newton tried to give an expe- particular, in physics, such a change coincided with the institu- rimental basis especially to ideas that he had not sufficiently tionalization of the course in Experimental Physics (Schettino, formalized (such as that of ether and that of interparticle forces), 2001). so that the results obtained by Newton by means of a complex Now, still in the XVIII century, what we now could call “re- relationship between inductive and deductive reasoning became search centres” of the newborn physics, were not necessarily truths demonstrable directly with experiments. distinct from the places devoted to the transmission of knowl- The Newtonian method underwent a profound remodeling edge, i.e. schools, colleges, etc. The success of a theory also with Desaguliers, a member of the Christ Church College who passed through its acceptance by “students”, i.e. scholars not held popular Newtonian lectures at Oxford, where he had much yet acquainted with it, who then contributed actively in the success in his activity (Hall, 1972). After moving to London in dissemination of novel ideas. In other words, if the first accep- 1710, he was welcomed into Newtonian circles of the capital tance of a given doctrine was disputed at a rather “high” level and was then (1714) elected fellow of the Royal Society, later between leading scientists and philosophers (as a reminiscence becoming the curator of the Royal Society, a position that was of the philosophical disputations of earlier centuries), the de- earlier held by Francis Hauksbee. Desaguliers published many finitive one was played in lecture halls before non-experts. An works on the Philosophical Transactions about experiments on illuminating example of this mechanism is just the general heat, mechanics and electricity. In particular, he correctly real- achievement of Newton’s mechanics, expressed in his Principia ized that the physical quantities then used for describing the (Newton, 1726). While its acknowledgement by leading school- motion of a body, i.e. the momentum for the Newtonians and ars is well documented in the literature [see, for example the vis
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