CONSIDERING that this nation of ours is totally obsessed with property prices, it is baffling that so few people understand what actually goes into the building of a house.

And I find it particularly infuriating when people who have been made rich by the property boom get onto their high horses to condemn a centuries-old Yorkshire Dales industry which made their wealth possible: quarrying.

Now I make my living driving around the Dales in summer and winter, rain or shine, and I hate getting caught up behind a quarry wagon. I hate being caught up by a convoy of caravans too. Both are bringing wealth and jobs into Craven.

Because I am privileged to live and work in such a beautiful area, I accept that other people here have a right to make a living here too, even if it causes me minor inconvenience.

So consider this arcane fact: the building of even a modest house requires at least 50 tonnes of quarried stone: limestone, mostly.

And only a tiny fraction of this goes into the mortar. The rest lies where the eye cannot see: in the sewers under the house and under the road that leads to the house. Without them, modern living would be unbearable.

To use a robust phrase given to me by a man who spent his working life in the higher echelons of the Yorkshire quarrying industry: "In Elizabethan days, people emptied their chamber pots by chucking them out of the window into the street. Thankfully, the Victorians came up with sewers - and the quarrying industry has been supplying the materials to build them ever since."

David Kirkham, 69, is normally a quietly spoken, amusing sort of fellow, a man fond of a joke and quick with a smile. He spent some 35 years in the quarrying industry and became a senior executive with Tilcon, handling the sale and delivery of millions of tonnes of rock for minor construction schemes like the M62.

But he can get quite cross when he reads of yet another attack of an industry which was one of the backbones of Craven life long before it became a bolt hole for second home owners and wealthy retirees who want quarry wagons off the roads or, in the more extreme cases, the quarries themselves closed.

"Craven locals have lived with quarrying for generations," he told me at his home in Greenacres, Skipton. "When tin and lead mining were still in business only a few decades ago, the Dales were an area of quite heavy industry - industry which provided thousands of jobs for local people.

"Admittedly, things have now changed - but so has quarrying. All quarry lorries have to be sheeted to prevent rocks flying out into the road. Huge amounts are being moved by rail again. And the quarry companies are spending fortunes on environmental improvements to screen the actual workings from view.

"I just wish that the companies were given some credit for this - and that the moaners would accept that ordinary workers have a right to the job, that the money they spend in local shops and pubs is keeping some villages alive."

If that sound like a rant, I have given the wrong impression. David Kirkham doesn't rant: he makes his points in quiet, slow, carefully thought out terms, coloured with regular flashes of humour.

If it were me, it would be a rant - because I agree with every word he says.

He was born in Cheshire, educated in Staffordshire and brought up in the North East where his father was a buyer with Angus Fire, the fire-fighting equipment company which has a base in Bentham.

After national service he was invited to join the quarry industry by an old friend. It was to prove his life career.

He became a Fellow of the Institute of Quarrying and in 1966 married his German-born, Norwegian wife Rosemarie. They had two children and moved to Skipton in 1970 when several northern quarry companies merged to form Tilcon and David was put in charge of sales for Yorkshire, Lancashire and Humberside.

"At that time, we had some 40 people working in the office on Belmont Bridge in Skipton," he recalls. "One Christmas, when we paid out three weeks wages for all the quarry workers, we had to draw over £30,000 in cash from the bank - that was a huge fortune in those days."

Retirement brought no slow down because David threw himself into charity work. He is the president of the Skipton and Craven Branch of the Multiple Sclerosis Society, where he has held virtually every office in the past 30 years, secretary of the Skipton Retired Men's Forum, and a member of the local branch of the University of the Third Age.

"I'm as busy now as ever," he said. "The MS society takes up a lot of time. We raise some £12,000 a year to provide extra support for some 100 sufferers - and we make sure that 90 per cent of that is spent in Craven."

I'm all in favour of that, too, because there is a telling statistic about charity work as well hidden as the sewers and road foundations built from Yorkshire rock. Of any money donated in Yorkshire to a nationally registered charity, 70 per cent is spent in London or the South East. Like David Kirkham, let's support local endeavour, whether it be business or charity.

* Anyone who might be suffering from MS, or would like advice on the subject, is invited to ring David Kirkham on 01756 79213