The 500 pound World War Two device was picked up during dredging work.
Swan Secrets Sought With Cyber Egg!
Scientists are hoping that a silicon-filled computerised egg will crack open the secrets of how cygnets hatch in Dorset.
The hi-tech device has been developed by Oxford University and is being used among the swans at Abbotsbury Swannery.
A swan lays four to 10 eggs at two-day intervals and incubation only begins when the last egg is laid. It means that the cygnets hatch together and can therefore be better cared for by their mother.
Scientists hope to use the technology to study the temperature of the eggs and the incubation process.
The cyber egg uses mobile phone-style accelerometers to measure movements up and down, left and right, and backwards and forwards.
It can record these movements and changes in temperature eight times a second, or more, and then transmits the data to a nearby base station.
Professor Chris Perrins, of the Edward Grey Institute of Field Ornithology at the University of Oxford, said:
''It's something that's puzzled us for a long time. Birds don't normally waste energy and yet some preliminary observations during the laying period indicate that a female swan does keep her eggs at least partly warm some of the time.
''But since the eggs hatch together, they are not apparently kept warm enough for development to take place. So why use up energy doing it at all? It seems odd.
''We want to understand in greater detail the amount of heat that a female puts into her eggs during laying and incubation, and why and how it's done.''
Abbotsbury has been home to a colony of mute swans for nearly 1,000 years, which are used to interacting with swannery staff and visitors. Benedictine monks established the swannery to supply swans for lavish banquets at the nearby monastery.
640 men were killed when the South African troop carrier was hit by a cargo ship in 1917.
The 79-year-old man suffered a serious head injury in the Cranmer Road car park in Winton.
Two Girls Indecently Assaulted Last Sunday
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