The story of "Project Azorian" and the Hughes Glomar Explorer (the ship this crane was first used to construct) is a Wikipedia hole perfectly sized for a Saturday and some coffee. Well worth reading if you haven't before:
Fun anecdote that Gen-X Baltimoreans may recall from youth - "chessy" was also the name of a myth about yet another prehistoric-esque aquatic beast that swam in the Chesapeake Bay waters (1). Silly Baltimore:)