The years immediately after the final downfall of Napoleon Bonaparte could easily have been years of anti-climax in French science. In 1815, after two decades of undoubted greatness, the time, I feel, was ripe for decline. And decline might well have occurred if the traditions and the style of science as practised in France in the period of Napoleon's rule had been carried on unchanged by the disciples of the two great men who had dominated work in the physical sciences for so many years. These men, of course, were the chemist Claude Louis Berthollet and the mathematician and physicist Pierre Simon Laplace.

“Whatever difficulty we might experience in the middle of the nineteenth century in choosing a king of science”, read the obituary notice in The Morning Post of Monday, 2 December 1872, “there could be no question whatever as to the queen of science.”1 And in a full-length column the death in Naples on the preceding Friday of Mary Somerville was announced. The Times of the same date, in a notice 2 of equal length and somewhat more scientific detail, spoke of the high regard in which her services to science were held both by men of science and by the nation. She had been for almost half a century the most famous of English scientific ladies and in achieving that role had become the first scientific lady of the world.

The publication of L. Pearce Williams's definitive biography of Faraday has led to lively discussion of the influence of Naturphilosophie on Davy and Faraday, and of the role played by Bosco vichean atomism in their scientific development. In a recent article J. Brookes Spencer argued that Boscovich's force law, involving interaction between point atoms independent of surrounding particles, was only compatible with Faraday's view of gravity and not with his views on other forces. This would of course contradict the notion of unity which is absolutely fundamental to Boscovich's Theoria.

It was in the closing year of the nineteenth century that Paul Tannery organized at an international historical congress the first international meeting devoted to the history of science. If antiquity would make a scholarly subject respectable, scholarship in the history of science must be beyond reproach; still earlier than Tannery and his colleagues in many European countries were the German historian of chemistry Kopp, and William Whewell, Master of Trinity; the eighteenth century had produced substantial works like those on mathematics and astronomy of Montucla and Delambre; Isaac Vossius and others virtually take these studies back to the Renaissance and Polydore Vergil. Just as in our day such classical scholars as Heiberg, Bailey, Housman, Drachman or Peck have chosen scientific texts as their subjects, so in the past, too, learning and science have met on this common ground. Few creative mathematicians of the seventeenth century thought that attention to the writings of Euclid or Archimedes was a waste of time.

The aim of this paper is to report some little-known aspects of sixteenth-century physics as these relate to the development of mechanics in the seventeenth century. The research herein reported grew out of a study on the mechanics of Domingo de Soto, a sixteenth-century Spanish scholastic,1 which has been concerned, in part, with examining critically Pierre Duhem's thesis that the English “Calculatores” of the fourteenth century were a primary source for Galileo's science.2 The conclusion to which this has come, thus far, is that Duhem had important insights into the late medieval preparation for the modern science of mechanics, but that he left out many of the steps. And the steps are important, whether one holds for a continuity theory or a discontinuity theory vis-à-vis the connection between late medieval and early modern science.

Attempts in antiquity and the Middle Ages to determine the mathematical law of refraction are well known. In view of the movement toward the mathematization of physical laws, which has made great gains since the beginning of the seventeenth century, and of the efforts of Hariot, Kepler, Snell, and Descartes to determine the true mathematical ratio between the angles of incidence and refraction, it is understandable that historians of pre-seventeenth-century science should concentrate on the quantitative aspects of refraction. But to do so is to gain a distorted picture of early optical thought, for as much effort was actually devoted to understanding the cause of refraction as to finding the mathematical law of refraction.

At the end of the last century Paul Tannery published an article on geometry in eleventh-century Europe, which he began with the following statement:

“This is not a chapter in the history of science; it is a study of ignorance, in a period immediately before the introduction into the West of Arab mathematics.”

The first attempted derivation by Galileo of the law relating space and time in free fall that has survived is preserved on an otherwise unidentified sheet bound among his manuscripts preserved at Florence. It is undoubtedly closely associated with a letter from Galileo to Paolo Sarpi, dated 16 October 1604, which somehow found its way into the Seminary of Pisa, where it is still preserved. Those two documents, together with the letter from Sarpi to Galileo which seems to have inspired them, are translated in full below. Sarpi's letter, dated 9 October 1604, suggests that recent oral discussions of problems of motion had recently taken place between the two men. It reads as follows:

“In sending you the enclosure, it occurs to me to propose to you a problem to resolve, and another that seems to me paradoxical.

From the time of the publication of Henry More's first work, the collection of poems, ΨγΧΩΔΙΑ Platonica (1642), Platonism provided the dominant theme in his philosophy. At Cambridge, More, his colleague, Ralph Cudworth, and their disciples, were responsible for a considerable revival of English Platonism, which became an important factor in late seventeenth-century natural philosophy. This movement is noted for its active and influential opposition to the mechanical world view, characterized in the writings of Hobbes and Descartes.

The list of Antoine-Laurent Lavoisier's opponents is a long and distinguished one, ranging from Joseph Priestley and Henry Cavendish to Jean-Paul Marat. Among the less distinguished members of this company is Antoine Monnet, a minor chemist and mineralogist whose fame rests in large part on the very fact that he and Lavoisier became enemies. Unlike his better-known contemporaries, Monnet remains almost wholly neglected, and no attempt has yet been made to sort out the issues in his controversy with Lavoisier; instead, Lavoisier's biographers have been content to accept Lavoisier's own version of at least a part of the affair, with the result that Monnet has emerged as the villain of the piece and Lavoisier as the injured victim. The two men probably first came into close contact in 1776 or 1777, the nature of their relationship has remained obscure for the period 1777–1780, and the situation after 1780 has been summarized by biographers in a manner resembling that of Edouard Grimaux:

“ayant en main tous les documents réunis par Guettard et Lavoisier, il [Monnet] ajouta de nouvelles cartes à celles qui étaient déjà gravées, et publia, en 1780, un altas minéralogique incomplet, qu'il signa avec Guettard, tout en s'attribuant la plus grande part du travail. Il cita, il est vrai, Lavoisier comme l'auteur des seize premières cartes, mais il utilisa sans son aveu et sans le nommer les matériaux préparés pour le reste du travail, et négligea d'indiquer que les coupes placées en marge de chaque carte étaient le résultat des nivellements faits au baromètre par Lavoisier. Celui-ci en fut vivement froissé … Il trouva toujours en Monnet un adversaire obstiné qui, en 1798, attaquait encore les doctrines nouvelles en publiant une soi-disant Démonstration de la fausseté des principes des nouveaux chimistes.”

Newton wrote in the Principia that all bodies are to be regarded as subject to the principle of gravitation. Every body, however great or small, is related to every other body in the universe by a mutual attraction. It was this postulated universality of the force of gravity which contributed so greatly to the order and unity of the Newtonian world. This unity was, for its followers, an untested article of faith for nearly a century after the Principia. During this time the evidence of gravitational attraction continued to be drawn from the motions of the earth, moon, planets, comets, and falling bodies—phenomena which span an intermediate range of masses, sizes, and distances. In three domains of experience, involving the extreme upper and lower limits of masses and dimensions, the action of gravity had not yet been observed: the gravity of the “fixed” stars; the mutual attraction of terrestrial bodies; and the gravitation of light. The task of deducing observable consequences from each of these supposed instances of universal gravitation fell to the Reverend John Michell (1724–1793), a teacher at Cambridge (1749–1763) and afterwards Rector of Thornhill, Yorkshire. His renowned London friend Henry Cavendish (1731–1810) encouraged him in these researches and became involved in the resulting observational and experimental questions. The immersion of Michell and Cavendish in gravitational studies was an essential feature of their commitment to a unified Newtonian world. Their commitment had yet a broader significance: Newton's theory of gravitation inspired their image of physical reality, and it served as their model of an exact science. This paper is an attempt to relate the personal friendship of Michell and Cavendish, their scientific collaboration, and their common Newtonian philosophy. Its chief focus is on Michell's 1784 plan for weighing the stars by the gravitational retardation of their light; his project of weighing the world by means of a torsion balance is treated by way of an epilogue.

Most modern analysts of Newton's laws of motion, whether they have approached the subject from a historical or from a philosophical viewpoint, have tended to concentrate on the status of the first two laws; the third law has largely been overlooked, or else it has been dismissed as somehow less interesting. My purpose in this paper is to reverse this approach—I intend to investigate some of the historical aspects of the third law, particularly the empirical background to Newton's statement of it, and in so doing, I intend to skirt most of the questions which have been raised concerning the status of the other two laws. In concentrating on the historical aspects of the third law, I shall also by-pass Mach's controversial re-interpretation of its role in mechanics, for while Mach saw the law as the basis for an operational definition of “mass”, it is quite clear that Newton did not so regard it. On the contrary, Newton seems to have regarded all three of his laws as straightforward statements of fact about the world, so that a knowledge of the factual background to the laws is a fundamental pre-requisite to an understanding of Newton's thought.

In 364 the German Schoolman, Henry Hembuche of Langenstein, or as he is more frequently called, Henry of Hesse, wrote an extremely odd treatise entitled On the Reprobation of Eccentrics and Epicycles (De reprobatione ecentricorum et epiciclorum) in which he attempted to refute Ptolemaic astronomy. We can be confident of the date, 1364, since Henry himself tells us that he is writing in that year. At that time Langenstein had been an M.A. at Paris for about a year, and was teaching in the arts faculty while pursuing the studies which were ultimately to bring him a doctorate in theology.

Thomas Thomson (177–1852) is primarily remembered as the author of the textbook A System of Chemistry which dominated the British field for about 30 years. In his chosen subject of chemistry his enthusiastic support of Daltonian chemical atomism and his zealous support of Prout's hypothesis have been recently recognized. Yet his activities were not as restricted as received opinion suggests. When Thomson assumed in 1818 the newly created Regius Chair of Chemistry at the University of Glasgow, the prospects for him as teacher and researcher were apparently encouraging. But he met difficulties in his attempts to elevate the status of the Regius Professors at Glasgow and in his concurrent endeavours to develop chemistry as an autonomous science. The ensuing controversy, first private and then public, spanned more than 20 rancorous years. Only one of Thomson's obituarists, however, even briefly mentions this debate; and recent writers on Thomson either ignore it completely or skim over it lightly. The main purpose of this paper is therefore to redress the balance of previous work on Thomson by outlining the chief features of his professorial period, paying particular attention to his style of teaching and attitude to his subject. For Thomson the development of his discipline was inseparable from the question of his status as a Regius Professor. Accordingly I also try to show that he played an important role in the movement for reform of the Scottish Universities and I discuss the structure of power at the University of Glasgow. Such analysis is necessary for understanding Thomson's appraisal of his situation as Regius Professor of Chemistry. In order to put his professorial period into the context of his earlier work I introduce the main body of the article with a short reconsideration of the form and significance of his career before 1817, when he moved to Glasgow.

Shortly before his death in 1934, the British historian of chemistry, A. N. Meldrum, published two lengthy articles on Lavoisier's early career in science. After a careful investigation of the collection of manuscripts at the Académie des Sciences in Paris and in light of a detailed and penetrating analysis of Lavoisier's published work, Meldrum concluded that as a youth, Lavoisier was concerned with chemistry only to the extent that he found it useful for his mineralogical and geological researches. Lavoisier began his career as a mineralogist; he became a chemist only in 1772, the “crucial year” when he turned his attention to chemical theory for its own sake and started his famous course of experiments on the nature of combustion and fixed air. Although some details—notably concerning Lavoisier's early education and geological work—have been added to this account since Meldrum's time, the broad conclusions of Meldrum's study are still generally accepted by historians of the chemical revolution.

Charles Babbage's Reflections on the Decline of Science in England … is very well known to historians of science who are aware of its role in the movement to found the British Association for the Advancement of Science and to reform the Royal Society. The work is probably responsible, in large measure, for the assumption that science in Great Britain was in a marked decline in the early decades of the last century, an assumption rarely subject to exact analysis although fairly widely held. Not as widely known is a reply to Babbage written by Gerard Moll of Utrecht and presented to the English reading public by Faraday, one of the men attacked in Babbage's volume. To the best of my knowledge, Babbage's only published rejoinder to Moll appeared in 1851, dismissing Moll and other critics as not having challenged his facts.

So great has been the impact of Darwinian evolution upon contemporary thought that even the tiniest aspect of Darwin's own history assumes importance as a datum in the history of those ideas which provide the ideological base of the contemporary world. In all of the accounts of the intellectual journey which led to the formulation of that theory, a great deal of stress is placed upon the Beagle voyage, that prolonged period of initiation from which the young Darwin returned, the sober—and too often in later accounts, sombre—naturalist, scientifically seasoned by his experiences with a world observed but still unexplained and hardly known. The traditional outlines of the story have been repeated over and over again: the outfitting of the Beagle for its surveying responsibilities; Fitzroy's proposal that “some well-educated and scientific person should be sought for who would willingly share such accommodations as I had to offer, in order to profit by the opportunity of visiting distant countries yet little known”; Henslow's recommendation of his friend and student Darwin; the parental refusal; and, finally, the permission granted. In the retelling, in the almost mystical affect attached to the Beagle voyage and to Darwin's participation, the association of the inexperienced youth with the Beagle has become a fixed point in intellectual history.