Diving for sponges

It is speculated that diving for sponges is the oldest profession on the Greek island of Kalymnos. It brought development to the island on both economic and social levels.

There, a crew would set out in a small boat. A cylindrical tool with a transparent bottom was used to examine the floor of the ocean for sponges. When one was located, a diver would jump out with a skandalopetra. This was a heavy stone which was used to aid the swimmer in reaching the appropriate depths. At the bottom of the floor, he cut the sponge and returned to the surface.

found on livingheritage.com