On Sun, 15 Jan 2012 19:07:50 -0500, Frank
wrote:

You don't lift ships. You put them in dry docks, where water is pumped
out to lower the ship onto the blocks. Guess you'd have to do it twice,
repositioning the ship.

Cruse ships dry dock every so often It may take many months to finish
the maintenance task if painting and repair of the hull. Pesky
barnacles and all.