Written by the Naval Staff, Anti-Submarine Division of Great Britiain and dated 1918.
http://www.archive.org/details/notesonsubmarine00grea

A note on the history of submarine war
by Sir Henry John Newbolt and dated 1918.
http://www.archive.org/details/noteonhistoryofs00newbuoft

Bewdie Joe!

Thanks again.

HMAS ARMIDALE was a WW2 Minesweeper, but like so many of her class was employed as a Jill of all trades.

Thanks Armidale.
Joe