The 500 pound World War Two device was picked up during dredging work.
Southampton Entrepreneur Could Buy Comet
Staff at stricken electricals chain Comet have been dealt a pre-Christmas blow after administrators announced a further 125 stores will close.
Deloitte said it would only keep the remaining 70 stores open until all remaining stock was sold.
It confirmed it was still in talks with a ''small number'' of interested buyers, but said it was necessary to begin shutting shops in the absence of a firm offer for the whole business.
Deloitte also plans to close the company's distribution centre in Harlow, Essex this Friday and will cut back office functions at Rickmansworth, Hull and Clevedon.
The announcement comes after hopes had been raised of a rescue deal after it emerged Southampton-based entrepreneur Clive Coombes was considering making a bid.
Chris Farrington, joint administrator at Deloitte, said store closures are likely to start next month, but added that the process will be delayed if they receive any ''acceptable offers'' for stores.
Around 5,000 employees work across the 195 Comet stores, with more than 3,000 jobs expected to be affected by the decision to shut 125 shops.
Comet employees are to be paid salary, accrued holiday pay, overtime and bonuses for the period covered by the administration.
Deloitte added that it has contacted more than 35 prospective employers who are ''keen'' to offer roles to ex-Comet employees.
The collapse of Comet marks one of the biggest high street casualties since the demise of Woolworths in 2008 and came a month after the failure of JJB Sports.
The group was hit by weak high street trading conditions, competition from online rivals and being unable to secure the trade credit insurance needed to safeguard suppliers.
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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