The Sunday Telegraph recently ventured into the jungle of Trafalgar Square, and asked twelve children whose statue was on top of the column. Only one correctly identified Horatio Lord Nelson. Some thought it was Nelson Mandela, and one teenager knew it was an admiral but thought it was the man who invented Wellington boots.

How sad that we seem to be losing touch with our old heroes. I am in favour of heroes, and told the stories of more than 200 of them in my TV series Local Heroes. Sadly I did not include Nelson, because I generally visited the places where the heroes worked, and demonstrated what they did - which would not have been easy in Nelson’s case without a tall ship and a disposable fleet or two.

Horatio Nelson was born in 1758, went to sea at the age of 12, and rose rapidly through the ranks, carelessly losing an eye and an arm in skirmishes on the way. In 1801 he won the battle of Copenhagen after putting his telescope to his blind eye so that he could not see his admiral's signal to retreat. Hence the expression ‘turning a blind eye’. Nelson was such a mega-hero that his name has become part of the language: a Nelson eye means the same thing as a blind eye, a Nelson knife is a knife with prongs that allows a one-handed person to eat food, and Nelson's blood is navy rum.

We often use naval slang without realizing: ‘No room to swing a cat’ comes either from the fearsome whip used for floggings, the cat o’ nine tails, or from the coal ships known as Whitby Cats – in a crowded anchorage the captain might well complain there was no room to swing a cat. ‘Bilge’ was the foul water that collected in the gutters around the ship’s deck. ‘Cold enough to freeze the balls off a brass monkey’ was all about cannon balls, stacked on a brass frame called a monkey; in seriously cold weather the frame would shrink and the balls would fall off. And ‘spinning a yarn’ was what sailors did - telling stories while they repaired ropes. I was once driving through Bradford with a tv producer; pointing out a sign on an old woollen mill – Fancy Yarn Spinners – he said ‘That’s more or less what we are.’