NavList:

Here is what Cotter had to say about longitude by the eclipses of Jupiter's moons. They were obviously used successfully by Cassini - on land. Using them at sea was almost impssible due to the motion of the ship. As is well known there were multiple attempts to get over that by special chairs (Mr. Irwin's was even tried on the voyage to the West Indies aboard the ship used by Maskelyne to test H4 - see my article in 'mare' which I attach).

Best
Wolfgang