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diving bell

An early diving bell used by 16th Century divers during salvage operations. The book this came from is a text on ship salvage and includes diving information.

Oath of Silence Protects Amazing 500-Year-Old Diving Bell Used to Visit Sunken Roman Vessels

A vow of silence has protected the mystery behind an ingenious invention for nearly 500 years. The secrets behind Guglielmo de Lorena’s amazing diving bell, a technical marvel, would have remained an...