Two French brothers, Alphonse and Théodore Carmagnolle patented, in 1882, the first design of an atmospheric diving suit or ADS. The helmet featured 25 small glass viewing ports of 51mm/2-inch. The body was articulated with the help of 22 rolling convoluted joints were never completely waterproof. The whole suit weighted 380kg/840lbs. It was build but never put in service.
