Pay off slip - and how to keep your money. The official title was Account of Wages. We used to get a small advance, called Channel Money, to tide us over when we arrived at our paying off port. Then we paid off at the shipping office the next day and collected the balance of our pay. This could sometimes be a significant amount, especially for someone who had no dependants. It was paid out in rather conspicuous, large, white fivers and must have been a sore temptation to some of the less honest denizens of the dockside, both male and female. So the Ministry of Transport printed it's advice on the back of the slip.
The document was the peculiar size of six and five/eighths inches wide by eight and one eighth inches long. In later years it was larger.