9

The emergence of chronometry in the Age of Enlightenment has been the subject of historiographical revisions in recent years. These have highlighted the importance of looking at the history of timepieces and their diffusion at sea and on land beyond the technological determinism and hagiographic readings that still characterise the history of horology. This paper shows the complexity of the processes involved in understanding how these instruments worked for the scientific communities for whom they were intended. From a user-oriented perspective, it examines the case of the pocket chronometers produced at the end of the 18th century by Josiah Emery’s London workshop. The study of the sources relating to these artefacts and the reconstruction of their biographies highlight the various parameters involved in the physical manipulation of a precision timepiece. From language to the gestures of craftsmanship, from the user’s body to his emotions, the chronometer is at the crossroads of social, economic, political, intellectual and material dynamics, each of which contributed to the making of science.