A few more parties that helped on 'Waterproofing' our Watches
After reading a huge book about diving watches (I had to do it) here below is the list in order of those watch companies that from the first military requests worked in developing and bettering watch-cases resistancy and use of chronometers underwater.
1870's - Breguet, Leroy, Vissičre (pocket-watches)
1890's - Nardin, Girard Perrgaux, Vacheron Constantin, Eberhard, Longines, Elgin (modified pocket-watches)
1920-30's - Omega, Officine Panerai (wristwatches)
40's - Hamilton, Ulysse Nardin (wristwatches)
50's Siegerin, Berg, Alpina, Jaeger LeCoultre, Seiko, Rolex, Blancpain (wristwatches)
60's Yema, Aquastar, Dodane, Tag Heuer, Auricoste (wristwatches)
All the above brands, officially supplied Marine forces in the world.
From Breguet to Auricoste, all companies worked closely (With great reinforcement of rewards) with military personals or sea professionals to ensure; water-resistance and underwater usage.
In the book I read (1991) it is claimed that the most reliable under-water readability was achieved by Officine Panerai ‘finally a reliable luminescent wristwatch thanks to the use of a radium painting’ ;-) and later it is said that in the early 1950's due to law changes Officine Panerai patented a new process known as 'Luminor' a tritium based paint'...
Yves
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