> and more to do with the fact that the British were the first people on Earth to invent a way of measuring longitude at sea accurately

...OTH if Britain wouldn't have been a globe-spanning empire, they wouldn't have needed a more precise way to measure longitude, and probably wouldn't have invented it ;)

E.g. the Brits had built a whole government body around the task, which then resulted in a competition, with Harrison's chronometer coming out as winner:

https://en.wikipedia.org/wiki/Board_of_Longitude

> Of course these are ultimately related facts - the same package of technology that allowed the British to produce people like John Harrison who were capable of innovating a marine chronometer also allowed them to produce ocean-going ships that could conquer a global maritime colonial empire (and that had a use for marine chronometers).

The causality you gloss over seems to be more important than the causality you'd like us to focus on. The ships came first.

Empire -> need for chronometers -> chronometers.