Thanks for that, Catlady. It must have made keeping appointments pretty interesting.
And it adds a new dimension to the potential confusion in traversing the globe in that era.
The other option for adjusting watches while they were on the move might have been using the map and converting back and forth from GMT. If you know where you were when you set it last, you can go back to GMT, then add on what you need for where you are now. I had it in mind that this might be what Fogg was doing.
Judging from the snippet of journal we see when they reached Suez (at 11am), Fogg was using local time in his journal, so it seems he had to be adjusting his watch or asking someone (other than Passepartout).
Side Note: There is also a way to
tell time with stars. There's something similar down here in the south, too, but I've never bothered to learn it.