In Australia, Dr. Antonio "Tony" Colcino, ageless diving hunter but also photography lover, one day long ago he thought it was good to combine the speargun and the underwater camera into a single piece of equipment. Of course, amphibious cameras did not exist so, it was necessary to design a case suitable for the purpose and the system to attach it to his spring speargun. He immediately realized that all the equipment was weighting too much also underwater, and he studied a way to balance it.
After several designs and projects here is his final creation, visible in the picture showing the inventor with a spy mask of that age in his forehead. The case allowed to probably place a photo or film camera, while its cover was a rubber balloon with a hose to inflate it by mouth to insert enough air sufficient to give to the totality a neutral hydrostatic balance. Brilliant and infernal, given that it is not difficult to imagine the hindrance of such a device while diving and the difficulties to manage it correctly both when shooting a fish and when photo shooting the environment. Unless the good Tony did not intend to tune the two moments to immortalize the precise instant in which the harpoon pierced the prey.