Jacques Cousteau developed the Shark Cage in the late 50s. A sturdy single cage designed to prevent sharks from approaching divers, and used for scientific observations & underwater cinematography. Today's 'Great White Shark' cages are built for tourism. The much larger tour cage can hold up to 8 divers. Presently, the U.S. Navy is using these larger cages for construction of undersea nightclubs, reserved for those servicemen who want to swim & party with the sharks.