Paul Weindling's paper, ‘Science and Sedition,’ which covers the period 1795–1819, appears to be a critical response to my own short note on ‘London science and the Seditious Meetings Act of 1817’. As several misconceptions are fairly formally iterated in Mr Weindling's treatment, I would like to take the opportunity of clarifying the issues, adding some further detail, and answering the one or two points of substance which have been raised with respect to my initial note. In an effort to save the valuable space of the Journal and avoid undue repetition, my reply takes the form of distinct but hopefully cumulative points, and remains centred upon the legislation of 1817, although I do permit myself some comments on the years 1817–20 as a coherent period.

In 1879 G. H. Lewes described the state of current British mental science. There were, he maintained, three main ‘schools’ of psychology. The first of these Lewes called the ‘ontological’ school; its members traced their lineage to Thomas Reid and to the common sense philosophers of the early nineteenth century, especially Dugald Stewart and William Hamilton. The second school was the ‘empirical’, which stood in the tradition of Locke, Berkeley, Hume, Condillac, Hartley, and James Mill. The ontologists and the empiricists differed in their theories of knowledge: the former held that certain beliefs were native to the mind; the latter that all ideas originated, mediately or immediately, from experience. However, both schools agreed on the object of psychological enquiry. They ‘quietly ignore the complex conditions of the living organism, and treat mental facts simply as the manifestations of a Psychical Principle’. Further, the ontological and empiricist schools concurred on the means by which this principle should be studied; both made introspection the ‘exclusive method of research’.

A recently published book, James Prescott Joule and the concept of energy, by H. J. Steffens, includes a chapter entitled ‘Conjectures on J. R. Mayer and J. P. Joule’. In it the author raises an intriguing possibility.

Joseph Glanvill is well known for his enthusiastic support of the early Royal Society. Even before Thomas Sprat's History of the Royal Society of London (1667) appeared in full, Glanvill had set a philosophic background for the new science in his Vanity of dogmatizing (1661), had attacked the outdatedness of contemporary Aristotelians in a revised edition of Vanity called Scepsis scientifica (1665), had praised the Society at length in a flowery address in Scepsis, and had defended the programme of the Society in his private correspondence. If propaganda and enthusiastic support were needed for the growth of science in Restoration England, no one seems to have done more to supply these ingredients during the early years of the Royal Society's existence than the colourful rector of Bath and Frome.

In the history of thermodynamics, two dates stand out as especially important: 1824, when Sadi Carnot's brilliant memoir Réflexions sur la puissance motrice du feu appeared in print; and 1850, when Rudolf Clausius published his similarly titled paper ‘Ueber die bewegende Kraft der Wärme’. In this paper Clausius narrowly beat the Scottish physicist William Thomson to the solution of a puzzle which had been highlighted in the latter's recent publications: how could Carnot's theory, with all its intellectual attractions, be reconciled with the newly discovered principle of the inter-convertibility of heat and work? Clausius's solution (as is well known) was to replace Carnot's axiom of heat conservation, with the axiom now known as the second law of thermodynamics.

In 1858, August Kekulé and Archibald Scott Couper independently published similar ideas regarding the tetravalence and self-linking ability of carbon atoms; three years later, the Russian chemist Aleksandr Mikhailovich Butlerov read a paper at the German Naturforscherversammlung in Speyer, which restated, clarified, and enlarged upon the ideas of Kekulé and Couper. In 1958, the centenary of the structure theory was celebrated in Chicago, London, Heidelberg, and Ghent; the celebrations in Moscow, Frunze, and Kazan took place three years later. For over a century chemists and chemical historians have disputed the origins of structure theory. Sometimes this activity has been confined to occasional sniping, but at other times determined battles have been fought. The polemic has never been characterized by cool and dispassionate discourse. Western historians have in general been unwilling or unable to master the extensive Russian literature on the question; the arguments of Soviet historians have often been clothed in Marxist rhetoric or otherwise influenced by political considerations.