The Panerai Crown Lock Patent
Thanks to Alessandro Gentilini, I was alerted to the presence of the original patent documents for the Panerai "tight seal device" in the US Patent Office's web site.
The first option for viewing these is to go directly to the page here. However this URL is 341 characters long, and causes some browsers to blow up.
Alternatively you can go here, and search for patent number 2954665.
You might get somewhere with this, however once you're there the data (so another Paneristi tells me) has been mangled by Lotus Notes / IBM Domino, and doesn't show up in most browsers.
What they're trying to show are two TIFF images.
At the end of the day I've mangled this into manageable GIFs for everyone to view!