Finding longitude at sea was a problem well before 1714, firmly established as a subject of scholarly discussion and debate among European philosophers by the 17th century. It was also a matter of practical interest to seamen and to political leaders of the major seafaring nations.

By the 1660s, active attempts were being made to develop marine timekeepers in England, the Netherlands, France and elsewhere. By looking at some of the surviving evidence of this work, including some of the timekeepers tested at sea at this time, this paper will explore the relationships between individuals, academic societies and states in the attempts to develop working machines for finding longitude.