Movement looks clean! Nice.

 

does Longines not mark their chronometer movements in any way?

 

Nice. I've often wondered what "chronometre" means on some of these oldies. Does it indicate a certain standard, or are they just letting us know it is a time piece.

Interesting pattern beneath the second hand. Has there been some rubbing?

 

Depends on the movement.

Depends on the watch in question. In this case, it indicates a certain standard. More info here: http://longines30l.com/wordpress/?page_id=189

 

That makes it more special than just a nice old watch. Thanks for the link.