The British Museum has been seduced by commerce, complains Alistair McAlpine
I have been invited by the trustees of the British Museum to visit the new Money Gallery, a venture supported by HSBC Holdings plc, the Hong Kong and Shanghai Bank, owners of the Midland. I suppose it was inevitable that, sooner or later, there would be a gallery dedicated to money. It is, after all, what the museum's problems are all about nowadays.

The British Museum recently mounted an exhibition called Mysteries of Ancient China which I found truly extraordinary. Many of the objects on display have no apparent use. Although scholars still argue about the purpose of these strange-shaped bronzes, I was quite struck by the similarity of many of them to parts of a motor car. It made me wonder if this was not an example of Chinese cunning, designed to receive the adulation of the West's most famous museum, so that when they were exposed one day as fantasies of the imagination, western cultural authorities would look feeble and stupid.

It has happened before. When the race was on to excavate the buried cities of the Silk Road at the end of the last century, the British government bought from a treasure hunter by the name of Islam Akhun dozens of fake manuscripts printed in a totally fictitious language.

Even more remarkable was the manner in which they were displayed, with enough space around many of the objects for them to be marvelled at in isolation. Where objects were shown in groups, the relationship of each to its neighbour was wonderfully artistic.

The show was a great success for the sponsors (the Times), and much money must have been earned from it. And here is the rub. The British Museum has become so conscious of cash that it has become a business.

Successive governments have starved our museums of money through the second part of this century. Recently museums have been encouraged by politicians to meet this problem by raising more money themselves - and the British Museum has been held up as an example by these politicians because it is now run efficiently along business lines.

But I left the Chinese exhibition wondering whether this is really the right way to display the contents of a museum. While such displays may well satisfy the conceit of the designers and the rapacity of the accountants, they are wasteful of space that is in very short supply and is expensive to construct.

The British Museum is a "wonder house" full of plunder taken by the British from other nations, as well as the goods and chattels of nations that have come to plunder Britain, and who left their possessions buried in our soil. In fact, the British Museum has such a vast collection that only a fraction of it - some 650,000 out of 6.5 million objects - is on show. This does not compare favourably with New York's Metropolitan Museum where virtually everything is on show.

The British Museum claims it rotates its collection, but the fact of the matter is that there are crates in their stores that no member of the staff has ever seen the inside of, let alone a member of the public. Indeed there is no one alive who has seen the contents of some of these crates. It would be more profitable for the archeological fraternity to excavate the store rooms of the British Museum than to scratch around in distant lands.

Instead, the Museum has become a business for showing and selling. Wandering around I found that it sells not only books, but large quantities of prints, copies and models of its famous pieces, and that is only the start.

The plan is that its revamped reading room should be replaced by a giant atrium soaring above the courtyard, complete with an education centre, lecture halls, seminar rooms, and with new shops, and a restaurant. They are very big on food at the British Museum. People reading books will soon be as extinct as the bookshops and reproduction souvenir shops of Museum Street, its cafes and restaurants, whose functions and purpose are gradually moved across the road.

The trouble is that museum directors have been seduced by commerce. That means they invite industrialists and people with commercial experience onto their board. These people know nothing of Cycladic art, medieval bronzes or Abstract Expressionist painting. So, when they try to be helpful, they suggest to the trustees that they expand the bookshop and open a restaurant - ignoring those who know that running a restaurant is one of the hardest ways ever invented to earn a living.

The more museum directors dabble in the world of commerce, the more they turn the neighbourhood they inhabit into a desert. What is more, they have to recruit shopkeepers, chefs and accountants to handle their business ventures when, in fact, they should be recruiting the best curators to rotate their collections, and paying them more - as well as giving them the back-up staff they need.

Because it needs to keep the tills ringing, the museum world has become obsessed with sponsorship. New galleries are opened; old ones are renovated and each time this happens two-thirds of the objects previously shown there go back into store. Space that would be devoted to the permanent collection is given over to spectacular but comparatively meaningless shows like that Chinese exhibition. No one calculates the real cost of the space that all these commercial activities use up. If they did, the accountants would find they cost so much that all these business ventures were run at a loss.

I long for a return to the days of the really great museums, such as the Soane Museum in Lincoln's Inn Fields and the Pitt-Rivers Museum in Oxford, where objects jostle for space - museums that give the feel of collecting and not of interior decoration where fine objects are tastefully displayed. That was how the British Museum once was.