OK, so I'm not quite sure why I didn't think of this before, but if I orient the spoon so the crown and letters are upright (bowl pointing up), they appear to begin with "EM" and end with "SS". After a little research, I discovered that Mappin & Webb made serve-ware for the RMS Empress, a ship that was owned by the Canadian Pacific Steamship Company and built in Ireland. The ship was ultimately sunk by the German submarine U-32 on October 28, 1940. The Empress was actually in the process of being towed back to Ireland after being attacked two days earlier by a German Condor long range bomber, so there were very few casualties.
Any thoughts?
Thanks,
Dave

