chronometer

He would set his pocket chronometer first thing, before tripping off in his buggy to clients who paid a fee to look at it and set their own timepieces.

Worsley’s navigational equipment was down to one compass, his sextant, and his tables—and of the twenty-four chronometers he had taken with him from London, he had only one remaining.

Plenty of interactive exhibits brings the voyage to life, including hands-on experimentation with a chronometer and Fresnel lens, outtakes from the duo’s journal, and short films.

But such was Worsley's genius with a sextant and a chronometer - maritime navigation instruments - there's high confidence in his calculated coordinates.

This could have been the forerunner of the kind of chronometer that would have been accurate and dependable enough to determine longitude at sea, and Hooke claimed to have worked out how to achieve this.