The 500 pound World War Two device was picked up during dredging work.
Rower Rescued In High Winds
A man had to be rescued after he got into difficulties as he rowed in his dinghy to reach his yacht in "appalling weather conditions''.
Winds were gusting up to 66 knots as a member of a local sailing club spotted the man in trouble in Portsmouth Harbour at 11.26am on Tuesday January 3rd.
A Coastguard rescue helicopter was scrambled along with a MoD police launch and a police rigid inflatable boat (Rib).
The man was found suffering from hypothermia on a mud flat next to his upturned dinghy.
David Williams, watch manager at Solent Coastguard, said: ''We were very concerned for the welfare of this rower - the weather conditions on scene were appalling with wind speeds up to 66 knots (which is Violent Storm Force 11 gusting to Hurricane Force 12 on the Beaufort wind scale) and driving rain.
''The rower was located on the mud by the police Rib, his overturned dinghy nearby.
''He was then taken by Coastguard rescue helicopter to Queen Alexandra Hospital, suffering from hypothermia. We believe he is now stable.
''We now know that this rower was in transit to or from his yacht in his dinghy.
''This is often a hazardous task and not something that we would recommend in such harsh weather conditions.
His lifejacket will have contributed to saving his life by allowing him to get to the sandbank where he was then found.''
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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