Lyr Req: Nine Days Out

Subject: Lyr Req: Nine Days Out - Chantey
From: Allan C.
Date: 10 Apr 16 - 11:04 AM

In the old Yul Brenner film, "Morituri" his character refers to the Tokyo blockade runners (presumably transporting supplies useful to the Germans during WWII)and quotes their chantey as, "Nine days out, all will be fair; ten days out, sailor beware." My sense is that this was invented out of whole cloth for the purpose of the story. But I thought I would ask if anyone may have heard of this in reality?