Funny you should say the Cap'n.
I know it is a question asked of me often as I roam the streets of Emu Park. People stop me and say is it called a Barque or a Bark when referring to Cooks Vessel.
I just tell them straight.
The B stands for Bark. In the 18th century, ships were classified by their hull shape. A ship with a flat bow and square stern was called a bark. If the ship didn't fit any category and its captain's rank was lieutenant, this ship was also classified a bark. Cook himself mostly referred to the original ship as "His Britannick Majesty's Bark".
They ask a lot of me in The Park.