1926?
Blancpain went against the flow and took a lot of these innovations and built the first automatic wrist watch? They were sort of the Microsoft of the swiss watch industry? They took Harwood's patents (an Englishman?) and combined them into a wrist watch.
As always, I'm sure I'm a little off with my data.
I can't find the first use of a screwed in caseback, but that's something near and dear to my heart as well. Same with a screwed in crown, and a case made from one piece of metal. Although I'm guessing Rolex had a part in both of those.
Keep em coming Yves!
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