Leading article: We are not short of masterpieces

How much longer can British museums, national and local, go on desperately launching last-minute appeals to save works which would otherwise go abroad. The latest example, a portrait of John Donne which is the subject of a £1.4m appeal by the National Portrait Gallery, seems to have been saved by a last- ditch grant this week of £750,000 by the National Heritage Memorial Fund (although the gallery still needs to raise a further £116,000 from the public). Less likely to be saved, however, seems to be the collection of William Blake watercolours now up for auction in New York and the Titian "Portrait of a Young Man" sold abroad for £60m, a sum which few believe can be matched in this country.

The problem is simple enough. The price of art is rising astronomically as private wealth increases around the world and the numbers of old masters available for sale goes down. Yet the funds that museums have at their disposal remains pitifully small and the sums available from outside funds, including the National Lottery, is beginning to dry up, despite the work of the National Heritage Memorial Fund, individual gallery patrons and the National Art Collections Fund.

Faced with the recent wave of appeals and the ever more extravagant sums needed to save them, the public could be forgiven for feeling it is a tide that cannot be turned and maybe should not be. Britain is rich with collections. Many of the works, including in the royal collection, remain hidden from view. There is no shortage of masterpieces, and far more immediate needs for public subsidy to help with the purchase of contemporary art.

The problem is one of policy as much as money. In the continuing drama of high-profile appeals, there has been little definition of what is important to retain in the country and what would simply be good to retain. The John Donne portrait is a case in point. This is a fine and rare contemporary portrait of one of the most important figures in British literary history. There is a strong case for the NPG having it for display. The recent £11m purchase of Raphael's "Madonna of the Pinks" is more arguable as is the Blake collection and the Titian portrait. There needs to be a special reason for keeping them other than quality to justify public subsidy.

If the Government, and the public, are not to be blackmailed into rescue every time an important work of art is threatened with going abroad, it needs a better set of rules for rescue. But in restricting its emergency assistance, it should also increase the regular acquisition funds for galleries so that they can keep - as every great museum must - their collections constantly refreshed and improved.