Archaeologists studying the wreck of a mid-second century Roman trading vessel found six miles off the coast of north eastern Italy believe they may have solved the mystery of a strange and unique feature found on board.
The ship's hull was pierced by a long length of lead piping near its keel. Marine archaeologist Carlo Beltrame, who works at the Ca' Foscari University in Venice and his colleagues have now put forward the idea that the pipework was there to supply fresh seawater to an onboard aquarium used to hold live fish in transit to market.
The archaeologists speculate that the pipe was connected to a hand operated piston pump (which the Roman's had elsewhere) and that this supplied water to a holding tank behind the mast which could have held up to 7 cubic metres of water.
They estimate such a tank could house around 200kg of live fish if sufficient water was circulated.
The wreck of the small trading ship measuring 16.5m, was first discovered in 1986 and recovered to a museum in 1999. Its remaining cargo consisted of around 600 large amphoras filled with salted mackerel and sardines alongside other fish products and this fishy freight helped lead the team to their new hypothesis.
Previous interpretations of the pipework have included on board fire fighting equipment or deck washing and bilge pumps, but Beltrame and his team believe the ship to be too small to warrant such devices.
They also site the writings of first-century Roman author and naturalist Pliny the elder who mentions the transport of live Parrot fish by sea, however no clear evidence of the tank itself has been found as yet.