I found this in a link on a post on Scuttlebutt and thought it may be of interest here. see this.
The rest of the site is very interesting to.
With thanks to brendanS.
Some interesting and curious definitions, and also omissions.
"Leak" as in fill with water I think we can guess.
But curiously, no mention of a wind backing, or veering, as now commonly used in shipping forecasts. Is this a modern useage?