Season 1 Episode 2 of Cambridge PhDcasts with PhDcaster Katy Barrett. Katy Barrett is a final year PhD student in the Department of History and Philosophy of Science at the University of Cambridge working on the cultural history of the longitude problem in the eighteenth century. For more details, including links to additional materials, please see www.crassh.cam.ac.uk/page/1188/katy-barrett.htm To find out more about Cambridge PhDcasts, go to www.crassh.cam.ac.uk/phdcasts Cambridge PhDcasts are presented by John Gallagher and produced by Richard Blakemore and Ruth Rushworth with thanks to CRASSH.