1 – What was the problem with longitude?

Why make a joke out of a niche and complex scientific problem? That is the question at the heart of this lecture series, which unearths the rich and surprising history of trying to find longitude at sea in the eighteenth century. Not simply a history on water, this is the story of longitude on paper, of the discussions, satires, diagrams, engravings, novels, plays, poems and social anxieties that shaped how people understood longitude. We start from a figure in one of Hogarth’s prints – a lunatic incarcerated in the madhouse of A Rake’s Progress in 1735 – to unpick the visual, mental and social concerns which entwined around a national concern: to find a solution to longitude.

2 – The Visual Problem

We consider the images and definitions employed directly by participants attempting to understand and find longitude. This sees us delve minutely into words, illustrations and maps. How was longitude defined as a word in the dictionaries that proliferated in the eighteenth century?  Why did interpreting the wording of the Act that launched the longitude problem in 1714 matter so much to its most famous respondent John Harrison?  And why did the way that longitude lines were drawn on a map, or that instruments for a possible solution were illustrated on the page, cause so much heated controversy?

3 – The Mental Problem – Proposing or Projecting

Lecture 3 looks beyond the direct concerns of definition and diagram to consider how language affected the credibility of different figures discussing longitude. Analogous to infamous projects like the South Sea Scheme, longitude spoke to fundamental contemporary concerns in the spheres of finance, politics, literature, religion and medicine. We find in plays, poems, novels and prints how crucial the language used to discuss longitude was to the ultimate solving of the problem.

1 – The Mental Problem continued – Madness or Genius?

The credibility of longitude ideas balanced on a fine line between madness and genius. The mathematical ideas that engrossed many longitude projectors could make them both mad and visionary, unable to communicate to the wider public. Yet a solution to the problem would, nonetheless, require a new association of ideas. Was this genius or madness? From plays to medical tracts, we find the longitude problem shaping eighteenth century ideas of mental capacity and see how longitude could be seen to drive you mad.

2 – The Social Problem

Moving from language to action, this lecture looks at how longitude was discussed in social contexts, and what interpretations might be put on different actors in scientific spaces. We analyse illustrations of science in wider society, alongside instruments, novels and paintings. ‘Science’ was an emerging discipline in the eighteenth century, and we consider how different spaces and technologies helped it find social capital: how longitude thus became both a polite, and a very impolite, science.

3 – Longitude in London

Hogarth’s Rake’s Progress print allows us a window into the eighteenth  century moment in which the longitude problem held intense public interest. As the story of longitude moved from paper in London to instruments at sea, so too Hogarth’s heirs in graphic satire took the elements of his print in different directions. The final lecture looks at how Hogarth’s image sits among a group of works that made the longitude problem visible in London and rooted it in this metropolitan context.