I don't recall the exact number of wives Blackbeard had, but it was at least nine. However, I never read of Blackbeard's having a room (or was it a closet in Bluebeard's case?) locked away that was forbidden for each wife to take a peek into. I think Blackbeard's method for ridding himself of a wife was just to sail away.

Jolly Roger regards,
WordintheWind