In 1875 Francis Galton was the first to study twins as a test of the relative strength of heredity and environment. This paper examines Galton's work on twins, using his surviving working papers. It shows that his enquiry was larger and more systematic than previously realized. Galton issued several hundred questionnaires to parents of twins, with the aim of establishing how far the similarities and differences between twins were affected by their life experiences. The paper also discusses Galton's study in relation to his understanding of the physiology of twinning and his theory of heredity. The modern concept of monozygotic twins had not yet been established, and the similarity between Galton's work and modern twin studies should not be overstated. While Galton's work was important as a pioneering study, in some respects his conclusions went beyond his evidence. The paper finally examines whether Galton's twin studies influenced his position on the links between social class, heredity and social mobility, and surveys the evidence for his views on these issues.

This paper argues that Goethe's collections, in particular his mineralogical collections, had both public and private purposes. The public purposes were closely tied to the tradition of mineralogizing exemplified by the Freiberg Mining Academy. Abraham Gottlob Werner provided technologies for standardizing mineralogical terminology and identification, and Goethe hoped that these technologies would allow for a vast network of collectors and observers who would collate their observations and develop a model of the Earth's structure. His own cabinet, in particular his collection of rocks (Gebirgsarten), was to be a representative sample of rock formations in particular locations that could reveal features of the Earth's structure and history. Goethe was also responsible for the scientific collections of Jena University. He argued that if such collections were to be useful for teaching and research, a goal he strongly supported, they could no longer be treated as the private property of professors. He recognized that social relations within the University would have to be reordered if museums were to fulfil their epistemic functions. In this respect Goethe was on the side of the modern museum and opposed to the world of the private collection and all its idiosyncrasies. However, his own collections had very private and personal purposes. Using some of the ideas of Walter Benjamin as a foil, this paper tries to uncover some of the private passions that fuelled Goethe's almost insatiable collecting. Though these passions were peculiar to Goethe, I argue that historians of science should attend more to the passions and their place in the sciences.

This paper uses the work of John Richardson, an eighteenth-century brewing theorist, to explore the view that physical quantities, though they appear ‘natural’ or ‘given’, are actually contingent entities constructed to serve particular aims. It focuses on the pounds-per-barrel extract, a brewery-specific quantity which, in a reversal of the familiar position, seems self-evidently constructed to the general reader yet came to be accepted as ‘natural’ among its users. Central to Richardson's work in achieving this acceptance was an instrument, the saccharometer, which, by providing measurements of the quantity, legitimated it. Richardson presented both instrument and quantity as tailored to serving the particular needs of his fellow brewers, at the same time emphasizing their separateness from parallel work in distillery assessment, which had made Richardson's innovation possible but now threatened his projected consensus. Richardson's overall project encompassed the direct proportionation of material costs, retail prices and Excise duties to extract values as defined by the saccharometer, which he sought to monopolize. The scheme was not wholly successful, yet Richardson's quantity remained in brewery use into modern times. The end result, I contend, shows how a quantity, by becoming naturalized, may survive the loss of its initial theoretical underpinning.