CHAPTER XIII.

THE BREAKWATER. Breakwaters, Ancient and Modern—Origin and History of that at 188 Cherbourg—Stones Sunk in Wooden Cones—Partial Failure of the Plan—Millions of Tons dropped to the Bottom—The Breakwater temporarily abandoned—Completed by Napoleon III.—A Port Bristling with Guns—Rennie’s Plymouth Breakwater—Ingenious Mode of Depositing the Stones—Lessons of the Sea—The Waves the best Workmen—Completion of the Work—Grand Double Breakwater at Portland—The English Cherbourg—A Magnificent Piece of Engineering—Utilisation of Otherwise worthless Stone—900 Convicts at Work—The Great Fortifications—The Verne—Gibraltar at Home—A Gigantic Fosse—Portland almost Impregnable—Breakwaters Elsewhere