Hi Anneradband. How interesting! I have periods where I try and find out what happened to my Great Uncle, Silas. He disappeared around the middle of the year 1923 and was never seen again by his family. A pile of clothes were found on the beach in Southsea, Portsmouth and it was assumed he had committed suicide. No body ever found and there was rumoured sightings of him. It was only a couple of years ago that I found the listings of him on the Orbita. Him jumping ship on 1st December 1923 fits in with his permanent disappearance from this country and all records.
Goodness, it may be likely he knew your grandad! I wonder what they got up to!! I guess we'll never know!