Early in 1826, at the age of 28, Charles Lyell began writing the first of a series of articles for J. G. Lockhart, the new editor of the Quarterly review. These articles gave him his first opportunity to express to the educated public his views on the state of science in general, and of geology in particular, in English society. According to the convention of the Quarterly, each article was nominally a review of one or more recently published works, but like other reviewers Lyell clearly chose them as ‘pegs’ on which to hang his own arguments. In content, the articles form a kind of ‘gradualistic’ series, rather like his own later interpretations of geological phenomena. At one end of the series (though published third) was an essay on the place of science in general in English university education. Another article (the first to appear in print) focused on some of the English institutions specifically devoted to science. Here there was a hint that the need for reform in the place of science in English society was not unrelated to a similar need for reform in Lyell's chosen branch of science. The next article enlarged on this hint by examining the publications of the Geological Society of London, on which Lyell had recently served as Secretary. This essay expressed for the first time in a general context Lyell's characteristic emphasis on the need for actualistic comparison between present and past. Finally, what he needed to complete the series was an article in which he could show in detail the positive explanatory advantages of following this method in geology. The ‘peg’ which he chose for this purpose was a single work, George Poulett Scrope's Memoir on the geology of central France.

There can be little doubt that 1973 will remain notable as a year in which knowledge of Galileo's mechanics increased dramatically. Professor Stillman Drake's publication, in May, of some of Galileo's early work on the law of free fall was followed in the autumn by the publication of a number of important manuscripts clearly indicating Galileo's use of precise measurement. From a discussion of these manuscripts and Thomas Settle's performance of Galileo's inclined plane experiment, Drake implies that a clear view of Galileo's use of experiment is now emerging. Added emphasis was given to Drake's thesis that doubts concerning Galileo's use of experiment were largely unfounded, by James MacLachlan's realization of a Galilean experiment which was previously described as ‘imaginary’ by Koyré. The purpose of this paper is to suggest that, while it cannot be doubted that Galileo used experiment and precise measurement, his attitude to observation may well have been far more complex than Drake has supposed. My point of departure is James MacLachlan's remark that continuing disagreement over Galileo's use of experiment should lead to further examination of Galileo's experimental claims. I shall indicate that more than one view of Galileo's use of experiment may prove capable of explaining our present knowledge—a corollary of this being that alternative explanations may be proposed for the manuscripts recently published by Drake.

The institutionalization of natural knowledge in the form of a scientific society may be interpreted in several ways. If we wish to view science as something apart, unchanging in its intellectual nature, we may regard the scientific enterprise as presenting to the sustaining social system a number of absolute and necessary organizational demands: for example, scientific activity requires acceptance as an important social activity valued for its own sake, that is, it requires autonomy; it is separate from other forms of enquiry and requires distinct institutional modes; it is public knowledge and requires a public, universalistic forum; it is productive of constant change and requires of the sustaining social system a flexibility in adapting to change. Support for such an interpretation may be found in the rise of modern science in seventeenth-century England, France, and Italy and in the accompanying rise of specifically scientific societies. Thus, the founding of the Royal Society of London may be interpreted as the organizational embodiment of immanent demands arising from scientific activity—the cashing of a blank cheque payable to science written on society's current account.

For the historian of thermodynamics, the outstanding events of the eighteenth century were the invention of the Newcomen atmospheric steam engine (1712), the patent of James Watt for a condenser separate from the engine's cylinder (1769), and Watt's further patent for the expansive use of steam (1782). These inventions, along with others concerned with hydraulic machinery, provided Sadi Carnot with the foundation on which he built, in 1824, the first fully general concept of a heat engine.

In two recent articles by Russell and Whiteside, the reception of those particular conclusions of Kepler that have come to be called his laws of planetary motion has been subjected to the first research beyond the pioneering efforts of Delambre at the beginning of the nineteenth century. Independently conceived, and directed towards quite different ends, these two investigations overlapped in only one substantial area—their survey of citations of Kepler's second law by English astronomers between 1650 and 1670. Not surprisingly, they reached essentially identical conclusions about the situation in 1670. Finding ‘equant’ theories instead of the law of areas, wherever he looked, Russell qualified his general claim ‘that the importance of Kepler's ideas during the period [up to 1666] has been greatly underestimated’, to the extent of describing the history of the second law as ‘chequered’ and ‘complicated’. And Whiteside simply reported that Kepler's scheme for reckoning motion in the elliptical orbit ‘was seemingly firmly accepted by no one, and even its formal enunciation but rarely stated in the period’.

One of the most dramatic advances in the physical sciences during the nineteenth century was the emergence of spectroscopy. It rapidly became an invaluable experimental technique for chemists and astronomers, while for physicists it opened a window upon the world of sub-atomic phenomena. Sir John Herschel played an important part, the value of which has sometimes been underestimated, in the early development of spectroscopy. This paper examines his contribution to the subject during the period 1819–61 in the light of his publications and of certain manuscript material preserved in the Royal Society's Library. Herschel corresponded with most of the scientists who did important work in spectroscopy during his lifetime, and he expressed definite opinions on most of the practical and theoretical problems that arose in it; however, the present study cannot pretend to offer a complete discussion of all aspects of the early history of spectroscopy.

In 1875 T. H. Huxley discovered that a secretion from the mould penicillium glaucum had an ability, unconnected with oxygen deprivation, to inhibit bacterial growth. He recorded his observations in his notebooks and in a single letter to John Tyndall, who at that time was a friend of Lister and a correspondent of Pasteur. Neither Huxley nor Tyndall looked for an explanation of this phenomenon, and neither told anyone else about it.

In the first half of the nineteenth century the largest and wealthiest ‘popular’ scientific establishment in London was the London Institution, founded by a group of prominent City men in 1805. During most of its early years this Institution had over 900 members; within a year of its foundation it had accumulated funds of £76,000, which dwarfed those possessed by any similar body in this period; by 1819 it had erected an imposing building in Finsbury Circus, a structure with a splendid library, a lecture theatre, and provision for laboratories, as well as meeting rooms. In that theatre eminent men of science and literature delivered lectures; by the 1840s William Robert Grove, then in the midst of his scientific career, was installed as ‘Professor of Experimental Philosophy in the London Institution’.

During the first half of the nineteenth century the Stirling brothers and John Ericsson made significant attempts to design hot air engines which could provide an economical alternative to high-pressure steam. They believed that it would be possible to gain fuel efficiencies superior to those obtained with steam by employing a heat exchanger within the air engine cycle, erroneously supposing that such a heat exchanger could eliminate the large loss of heat incurred in the condenser of the steam engine. The Stirling brothers called their heat exchanger an economizer because it prevented the waste of heat, but Ericsson coined the term regenerator because he imagined that the power of the heat (caloric) could actually be regenerated, i.e. re-used in the engine to generate mechanical work. Ericsson's term became commonly accepted, so that Stirling's economizer is now also referred to as a generator. These attempts to attain high horsepower outputs with hot air engines were abandoned after the dramatic failure of Ericsson's notorious paddle steamer in the early 1850s. Further ventures were aimed at the more limited goal of low horsepowers and generally ignored the regenerator principle.