Roman Mars

Crucially, though, the money was only a thank you.

It was not the Longitude Prize, which the board maintained he had not earned.

Harrison died in 1776, just a few years later.

And it did take a minute or more like a few decades for manufacturers to even come close to replicating the near perfection of H4.

But by the early 19th century, variations of Harrison's sea watch were everywhere.

These instruments became generically known as marine chronometers.

By the time marine chronometers were widespread, Britain had abolished slavery and left the transatlantic slave trade.

But it was colonizing faster than ever, spreading beyond North America and the Caribbean and into Africa, Asia, and the Pacific.

And since any tool that helped navigation helped imperialism, the marine chronometer was a key part of the evildoings.

James Cook used his Harrison-style chronometer on his second voyage.

He took it south of the Antarctic Circle, where he surveyed parts of the world never before represented on European maps.

And the logbooks on his ship, the HMS Resolution, called the chronometer our trusty friend, the watch.

Greenwich, England was chosen as longitude zero, the prime meridian.

And with that, England, with the help of John Harrison, became, cartographically speaking, the center of the world.

After the break, we talk about a method for long-distance sea travel that existed millennia before Europeans cracked longitude.

So I'm back with Kelly Prime.

I hear you have some more for me.

Totally.

That's totally true.

I mean, to me, there is nothing simple about navigating thousands of miles between tiny islands in the middle of the Pacific Ocean.