Xlg Diving Helmet 0
Modern Mechanix 1933 – “First, select a big tin can about 10 inches in diameter and 13 or 14 inches deep. Ask your grocer for a cookie can. Cut a hole in one side about 5 inches square and by means of tin channels soldered around this opening, set in a plate glass window, making it watertight by shifting around it with cotton dipped in thick shellac.”Link.