Aye, astronomical was what I was vaguely supposing, but I found it a bit weird to measure anything astronomical within 60 seconds
Relating to the time 12.5, etc, again this scale is limited to 60 seconds
Thanks for your reply, the fact that no one else comes up with a clear answer leads me more and more to think how strange this is. May be simply those contractors had that model already for industrial purposes and handed it by hundreds to the Kriegsmarine...and there's no special nautical reason for the scale.