@ Paul Burke
I sing this song. Re. the ship changing names - I believe this comes from a mixing and changing of the words over generations of oral transference, which is a pretty common occurrence lets face it and the Copper collection has plenty of examples of it. I sing:

We had not been many leagues at sea before a ship we spied
she being some lofty Frenchman come bearing down so wide
We hail-ed her in French boys we axed from where she came
her answer was "from Liverpool and London is our name"

The point being that the Frenchman was sailing under a false flag and was caught out by replying in English with a false name and home-port after being hailed in French.

This explains the line in the next verse when Somerville says to the Frenchman:

"come strike your English standard and then you must heave-to".

Hope this makes sense.

Regards , Kev.