Spherical Hyperbaric Chamber ID: 3508 | This file appears in: Cunningham Sanitarium The five-story, sixty-five foot, 900-ton sphere was constructed out of half-inch steel plates. Many likened the tank experience to that of a ship. With three tanks in total, light was allowed into the hospital through 350 ten inch portholes. Image Courtesy of Cleveland State University. Michael Schwartz Library. Special Collections. Download Original File "Spherical Hyperbaric Chamber" appears in: Cunningham Sanitarium