Tim and Pru’s touching voyage on their boat is balm to the soul

Every morning in Factory House, a grand temple to historic commerce with chandeliers and sweeping stairways in Porto, Portugal, a copy of a newspaper exactly 100 years old is ceremoniously laid out.

It’s a homage to the past and a reminder that we should never be in too much of a hurry to rush into the future — let’s face it, by the year 2117, 100-year-old webpages won’t have that same romance.

In the same way, the love affair of Prunella Scales and her husband Timothy West, Britain’s favourite waterway voyagers, is growing richer with age.

They repeatedly paid affectionate tribute to each other in Great Canal Journeys (C4) as they explored the Douro river from the vineyards to Porto warehouses on the coast.

This occasional series has never hidden Pru’s increasing frailty. Now 85, she suffers from dementia, and Tim, 83, sadly revealed that her day- to- day memory has evaporated completely.

‘ everything has to have an immediate impression,’ he said, ‘because she doesn’t remember anything. But that’s par for the course — she enjoys being here and she likes being with me and I like being with her. That’s the best we can hope for . . . and very nice, too.’

He didn’t sound remotely sorry for himself, nor was he putting on a brave face. The two of them were simply having a jolly good time — and he was relishing it.

Pru’s memory might be slipping, but her sense of humour is intact.

‘ Like good vintage port our marriage improves with age,’ she said, with a mischievous glint.

‘The secret is he’s the nicest person I know, nearly the most intelligent and nearly the most attractive.’

And then she added: ‘ After 54 years of marriage I’ve decided you’ll do.’

Plenty of stimulation and cheerful occupation is the best treatment for dementia and the magnificent cliffs hemming the Douro, with its plunging locks, were excellent therapy.

‘ This trip seems to be the perfect tonic,’ Tim said. ‘Pru’s on top form.’

We’ve been travelling with this delightful couple of unabashed old thesps, always ready to quote a scrap of poetry or a famous stage line, for nearly four years.

From the outset, they have treated each trip as if it might be their last, but happily they keep finding new places and extra energy for exploring.

Their latest journey brought the added advantage of fine port and lots of it. This too seemed to do Pru the world of good. A river cruise, endless supplies of wine and stunning countryside . . . it should be on NHS prescription.

The next best thing, of course, is a good laugh. But these were in short supply as Live At The Apollo (BBC2) returned for a new season of stand-up comedy.

The compere was Sara Pascoe, who opened with an ill-judged routine about how much she detested going to the theatre.

The gilded splendour of the Apollo stage was possibly not the best setting for her confession and her remarks were met with embarrassed titters.

Gary Delaney, also a writer, followed her, with a barrage of one-liners, such as: ‘I’ll tell you what always catches my eye — short people with umbrellas!’

Firing these clever gags off in bundles is a waste. He should be writing sitcoms, not performing live.

Larry Dean closed the show. Though he’s less well-known, Dean is the natural star of the trio. The Glaswegian has real stage presence and adds a menace to his gags.

It took 22 minutes for the first Brexit joke to surface. That must be a record for a BBC comedy show.