'The Dolphin' is a multiple rewrite by the hacks of a song written by Capt Phil Sumarez in 1745 re his own part in a skirmish his ship HMS Nottingham was involved in. 'Sam Hall' is a supper room piece sung by W G Ross in the early 19thc but based on a broadside song 'Jack Hall' a true story from about 1706.

As for those in the PBEFS I'm sure Steve would have given notes on their probable origins.