Measuring Gravity more exactly or the Significance of Experimental Research on the Density of the Earth and Big G, 1798-1898: Changing Pursuits and Long-term Methodological Continuity

This paper seeks to provide a historically well-informed analysis of an important postNewtonian area of research in experimental physics between 1798 and 1898, namely the
determination of the mean density of the earth and, by the end of the nineteenth century, the
gravitational constant. Traditionally, research on these matters is seen as a case of 'puzzle solving.'
In this paper, I show that such focus does not do justice to the evidential significance of
eighteenth- and nineteenth-century experimental research on the mean density of the earth and the
gravitational constant. As Newton's theory of universal gravitation was mainly based on
astronomical observation, it remained to be shown that Newton's law of universal gravitation did
not break down at terrestrial distances. In this context, Cavendish' experiment and related
nineteenth-century experiments played a decisive role, for they provided converging and
increasingly stronger evidence for the universality of Newton's theory of gravitation. More
precisely, I shall argue that, as the accuracy and precision of the experimental apparatuses and the
procedures to eliminate external disturbances involved increasingly improved, the empirical
support for the universality of Newton's theory of gravitation improved correspondingly