SEALAB

SEALAB I, II, and III were experimental underwater habitats developed by the United States Navy in the 1960s to prove the viability of saturation diving and humans living in isolation for extended periods of time. The knowledge gained from the SEALAB expeditions helped advance the science of deep sea diving and rescue, and contributed to the understanding of the psychological and physiological strains humans can endure.

SEALAB I was lowered off the coast of Bermuda on July 20, 1964 to a depth of 58 m (192 feet of seawater (fsw)) below the sea's surface. It was constructed from two converted floats and held in place with axles from railroad cars. The experiment involved four divers (LCDR Robert Thompson, MC; Gunners Mate First Class Lester Anderson, Chief Quartermaster Robert A. Barth, and Chief Hospital Corpsman Sanders Manning), who were to stay submerged for three weeks. The experiment was halted after 11 days due to an approaching tropical storm.

Before the SEALAB habitat could be emplaced, a number of rifle grenades had to be found and removed from the bottom around Argus Island. The grenades had been fired up into the air with the object of targeting their explosions when they returned to the water. With enough impacts the position of Argus Island could be determined to within a few feet. Unfortunately, many grenades did not detonate upon impact with the sea surface, and divers had to locate and remove them. This was a job for divers from the Navy SOFAR Station (Columbia University Geophysical Field Station), and both U.S. Navy and Air Force civilians and enlisted SCUBA divers. A platform which had been built to lower the Remote Underwater Manipulator (RUM) from a garage on Argus Island to the sea floor was also removed. SEALAB I was then placed on the nearly flat bottom on a layer of algal balls and some corals.

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