“No vessel has hatches that will admit a mass sixty-nine feet in length. [The obelisk] could not have been carried on deck in safety without strengthening the vessel at great expense. In the hold, below the water-line, was the only place where it could be securely stowed and safely transported, and how to get it there was the one thing on which the whole operation of removing it successfully turned. The plan devised and successfully executed consisted simply in embarking and disembarking the obelisk [by sliding it on cannonballs in and out of the hold] while the bow of the vessel was out of water, through an aperture opened expressly for the purpose and subsequently closed for the voyage.”