Never DID understand the day/night feature ... stick your stupid head out the window !
That works fine until you travel longitudinally and want to know what time it is ‘back home.’
If you are in a cave or basement—the day-night feature would be handy. But, admittedly, its a limited feature. I wish more of our technolical elements were made with more decoration. This watch was for a rich man and was state of the art for the time. I guess I am more a Captain Nemo type and would like our world to look a bit more like the 19th Century.