I think this post is right that Franklin would've been impressed by GPS. The author doesn't call it out, but the Longitude Problem was a significant area of scientific and engineering inquiry in Franklin's lifetime, with special focus on the difficulty of doing so at sea. I haven't looked into it, but given his research mapping the Gulf Stream it seems likely he spent time on the problem himself.
this reminds me of that site linked here last year that explained and diagrammed the inner workings of a wristwatch. I used singlefile to save the page, as i do with any page that impresses me (or is noteworthy or newsworthy or needs to be saved as proof, etc)
https://en.wikipedia.org/wiki/History_of_longitude