HAVING for years been able to say "I Saw It" - the 1981 Test Match climaxed by the legendary heroics of Ian Botham and Bob Willis - I can now also say: "I Heard It". Not that same event, but one that stands equally as a towering landmark - Alistair Cooke's final Letter From America.

The last of 2,869. It's possible that, back in 1946, my indifferent eight-year-old ears heard the first Letter too, for my late father was a regular Letter listener. It became a fixed point in a changing world, though its endurance owed nothing to nostalgia, but everything to its unfailingly-engaging content and the supreme craftsmanship with which Cooke put it together.

Typically, he began at a tangent to his main theme. Diverse aspects and digressions were linked seamlessly. The art hid the art, and the listener was always eagerly awaiting Cooke's next sentence. Strangely, print dispels the magnetism. The padding shows and the key points emerge too slowly. Since the Letter was designed to be heard, this does not devalue it.

Unaware that I was hearing Cooke's adieu, I don't remember how he opened his final Letter. But I remember its end. Cooke got round to the Iraq war and the President's attempts to explain the absence of weapons of mass destruction. He recalled how, in the film Casablanca, the Humphrey Bogart character, Rick, is asked to explain his presence in the town. "I came for the waters," he says. Told there are no waters, he replies: "I was misinformed."

That quote, the last words of Cooke's last Letter, is a genuine quote. Cooke - of course one of the most distinguished journalists of his age - once said: "I think all journalists make up all quotations. I'm always saying 'Somebody once said, and wisely', and then I quote something I just made up. Nobody ever changes it if it's in quotes, you see." He added that he left The Guardian "because they're so ethical they would have looked it his invented quote up and changed it."

Among Letters that I particularly remember with gratitude was one about the bus boycott in Montgomery. But only a week or two before Cooke decided to pull his own plug, he delivered a fascinating Letter chiefly about the building, and subsequent destruction, of New York's Pennsylvania Station. But time had caught up with 95-year-old Cooke in more ways than the frailty of old age. Broadcast the week after he retired, a 1996 Letter told how a rocking chair was covertly taken everywhere with President Kennedy, to allow him to relieve severe back pain.

Cooke thought it admirable that the media kept the chair's existence secret and, earlier, colluded in ensuring that images of President Roosevelt never showed the wheelchair in which he was confined. He considered that the likely exposure of disability in similar circumstances today would reflect a harsher world. It hadn't occurred to Cooke that disabled people no longer want their disability to be covered up, as though it is something to be ashamed of. But it is a measure of the Letter's quality that we could take such social slippage yet go on listening. Right to that final Casablanca quote, Letter From America was a glorious adornment of British broadcasting.