The Pyramids in the Sea

The building of the bar across the Bay of Cherbourg, France, enclosing a safe naval harbor, is one of the "Seven Wonders of the Modern World."

The project of making such a harbor on the north coast of France, opposite England, was first advanced and attempted by Louis XIV., but was soon abandoned. It was Napoleon I. who said: "I will erect the Pyramids of Egypt in the Sea." England was ever his most persistent foe; what mattered to him the cost of erecting a whole chain of pyramids in the sea, if they protected France from England! And so the prodigious work of building a stone wall in the sea, two and a half miles from the shore, was begun by Napoleon I., and completed by Napoleon III., after fifty years of labor, at a cost, with the docks, of five hundred million dollars. This great sea-wall is nearly three miles long, and over one hundred feet broad at the top. Queen Victoria witnessed the ceremony of dedication in 1858, just one hundred years after the English had taken Cherbourg, in 1758, and had destroyed its forts and shipping.

Owing to the great force of the water rushing through the English Channel, a mole, or stone wall, jutting out from the land was impossible. The plan adopted successfully by Napoleon was a chain of thirty-three cones constructed of oak, each cone one hundred and forty feet in diameter at the base; sixty feet in diameter at the top; sixty feet in vertical height; sunk in the sea thirty to thirty-four feet at low water. These enormous cones of oak, made water-proof by coatings of bitumen, were filled with stone to the weight of one thousand tons. To float them to the desired spot, sixty casks, made buoyant by being filled with compressed air, were attached to each cone. The cones were towed, in the presence of innumerable spectators, to the spot where they were to rest for all time. At a given signal the casks were cut loose, and the weighted cones instantly sank; each cone was then filled with stone from vessels in attendance, and each cone, when capped with solid masonry, became literally a "Pyramid in the Sea." The rest of the wall was simple and easy of construction. Between the cones, which touched at the base, stone was pounded down, and then, as on the Pyramids, large granite casings were fastened up the sides, secured with hydraulic cement. A broad esplanade crowns all, upon which strong forts are built, and machinery for the manufacture of all modern weapons of defensive warfare, for the heating of cannon balls, the manufacture of destructive bombs, etc.; so that France no longer fears an invasion from her English neighbors, just eighty miles distant across the Channel at Cherbourg.