My grandfather was a tug boat captain. He had his own boat & worked for the Pennsylvania Railroad. He remained a civilian during WWII. I imagine the Merchant Marine pass showed security clearance, which is why it was issued. He had throat cancer and was hospitalized at the US Naval Hospital in Baltimore. I never understood how he wound up in that hospital as opposed to King's County, but it's now beginning to make sense. The US Naval Hospital is now part of Johns Hopkins - whom I contacted regarding old records. They don't have any. I thought maybe I could get this 'z number' from the hospital records, but no such luck. My grandfather died in 1946, so I don't believe the VA came into the picture. I obtained a schedule of pension payments from the Railroad Retirement Board, but that was all they could give me. Is there any chance the RRB would have the 'z number' somewhere in their records? I know that's a long shot. Take care, Tracy