Adventures of a Sea Hunter_ In Search of Famous Shipwrecks - James P. Delgado [95]
Work on the submarine began in early 1864. On June 14, Kroehl wrote to the Navy’s Chief of the Bureau of Yards and Docks to press his case: “I sent you last week a pamphlet issued by the Pacific Pearl Company, for whom I am now building a submarine boat… In the operations against some of the rebel forts and harbors I have no doubt the Navy Department will require submarine boats, and I think it would be advisable to bring this to the attention of the Honorable Gideon Wells, and have the plans examined by a proper board.” The following day, he received a reply. The plans were interesting, and he should send them to the Secretary of the Navy. Kroehl did so, and on June 18, just four days later, was told by Secretary Welles to present his plans to W.W. Wood, the Chief Engineer of the United States Navy.
Sitting in a folder in the National Archives is Wood’s meticulous eighteen-page report on Kroehl’s submarine, written after he toured the vessel as it was being built in New York. Wood also drew up a large plan of the submarine—a sheet of paper that rolls out 3 feet—fully one-twelfth of the length of the actual craft. Reading the report and perusing the plan, it is obvious that the submarine on the beach at Isla San Telmo is the same vessel. The chamber on the top, according to Wood, was the “compressed air chamber… it has a semi-elliptic form and is built of two shells of best boiler iron % inch thick, the different pieces lapping 4 inches are double riveted with % inch countersink rivets, and braced with ribs of 3½” × 3” × ½” angle iron and 1 inch braces.” That kind of intricate detail is invaluable to an archeologist.
Wood’s report goes on to explain how a compressor inside the submarine was used to build up sufficient pressure to not only clear the upper ballast chamber to enable the submarine to rise but also to pressurize the hull to allow the unbolting of bottom plates so that the crew could reach into the water and harvest pearls—or to serve the purposes of war. This self-propelled “lock out” dive chamber—which many historians think is an innovation of the twentieth century—was designed and built in 1865. Wood’s report concluded by enthusing that “the uses to which a boat… in Naval Warfare, would be the removal of submerged obstructions in the channels of rivers and harbors. Approaching hostile fleets at anchor and destroying them by attaching torpedoes to their bottoms and exploding such localities as are commanded and covered by the guns of an enemy. The importance of a successful application of the principles involved in such a vessel for such purposes are of much importance and can not be too highly estimated.” Julius Kroehl couldn’t have said it better himself. It is a glowing endorsement, and I wonder what happened. Why didn’t the Navy buy the sub?
A section drawing of Sub Marine Explorer from the Journal of the American Society of Naval Engineers, 1902. James P. Delgado.
Part of the answer is that the submarine was not yet finished. Another is that the war was winding down. Most of the major ports of the South had fallen, the Mississippi was secured and the collapse of the Confederacy was just a few months away. With the end of the war imminent, the Navy Department probably viewed Kroehl’s submarine, brilliant though it was, as coming a bit too late. A genius, yes, an engineering breakthrough, yes. But the time for such an invention to help “win the war” had passed.
And so the Union Navy, which had already invested much in the unfortunate sub Alligator, declined Kroehl’s offer. But there were still pearls to harvest in Panama, and the Pacific Pearl Company used Wood’s letter as an endorsement, publishing