The Galvanic Connections of the Airy Transit Circle and the Airy Chronograph

摘要

Electrifying the Observatory. The Royal Observatory at Greenwich was the centre of British time and space during the middle of the nineteenth century. The Observatory distributed Greenwich Time through telegraphic connections to sites in London and to other locations around Britain. Meanwhile, establishing the Greenwich Meridian helped in the construction of maps, nautical charts, and on the projects of the Ordnance Survey. Combining the two applications aided navigation at sea. Previous studies in the history of astronomy have focused on the national dissemination of time. For example, James Nye and David Rooney highlighted the interactions between the Observatory and the companies disseminating its time, while more recently Yuto Ishibashi called attention to the installation of a new ensemble of instruments and clocks that served as the basis for time distribution. Yet, the way in which time was actually produced by astronomical instruments and transmitted between the various instruments and clocks inside the Observatory have received relatively little attention within such works. Focusing on the 'electrification' of this internal production process of time during the middle of the nineteenth century showcases how the different instruments were connected to each other in the long chain of time production.