FOUR of the most beautiful and remote islands off the Scottish coast - once described as ''heaven on earth'' - have been bought by the National Trust for Scotland (NTS) for #450,000.

Mingulay, Berneray, Pabby, and Rosinish, known collectively as the Barrahead Isles, lie due south of Barra and Vatersay, some 80 miles from the mainland. Only St Kilda, also owned by the NTS, lies between them and North America.

The owners - six crofters from Barra forming the Barrahead Isles Sheep Stock Club - put the islands on the market two years ago. Offers of up to #1m were expected, but none came to fruition.

The deal comes in the wake of two other high profile sales - of the Black Cuillins on Skye, still on offer for #10m, and Ben Nevis, which was sold to the John Muir Trust, also for #450,000.

NTS director Trevor Croft said yesterday that negotiations had been going on for some time and the timing alongside the other deals was purely coincidental.

He said: ''I am delighted that the Barrahead Isles are to come into our care as they really are exceptional in terms of their heritage and value to the people of Scotland.

''These are islands on the edge of Europe which are emotive because of the Mingulay boat song, and islands that should be in the heart of everyone in Scotland who thinks of their heritage, particularly the heritage of the outer fringe.''

Both Mingulay and Berneray enjoy special UK and European conservation status as breeding areas for seabirds, particularly for razorbill, guillemot, fulmar, kittiwake, and shag.

Mingulay, the largest of the group, has been purchased largely through a bequest left by a rich and remarkable Yorkshire woman who liked Scotland and driving fast cars. She also held a commercial helicopter pilot's licence.

Miss Jean Fawcitt, of Harrogate, left #1.7m to the trust, its largest legacy in recent times, in 1997, in memory of her parents and a brother who was killed in the last war.

Her estate included a brand new Jaguar which was sold at auction.

She stipulated that the proceeds should be used to secure remote and uninhabited areas of Scotland.

Scottish Natural Heritage provided a further #75,000 and #50,000 each came from an anonymous NTS member and the Chris Brasher Trust.

In 1880, Mingulay supported a population of 150 and with its 700ft sheer cliffs bears remarkable similarities to St Kilda. But its people left nearly 30 years earlier in 1912. It has no jetty or landing stage, and access is via the beach or a helicopter.

Mingulay's architectural legacy reflects two religious traditions. The old school house was built by the Free Church Ladies' Association and is still used as a bothy. A Catholic chapel and priest's house stood above the village and only lost its roof when battered by storms some three years ago.

There are also extensive archaeological reminders of even hardier souls who populated the islands in Viking, Pictish and Celtic eras.

Mr Brasher, who once described the islands as ''heaven on earth'', said: ''On my last visit to those unsullied beaches, I was telling the one-year-old son of the skipper of our boat that when he grew up he might see holiday hotels littering this paradise.

''So I am thankful that they are now in the care of the National Trust for Scotland and I am delighted that we have been able to help with their purchase.''

Mr Andrew Bachell, NTS director of countryside, said yesterday it would work closely with the people of Barra and Vatersay to develop a management plan for the islands.

He said the purchase represented a remarkable opportunity and an endowment fund would be set up drawing on the Fawcitt legacy to manage the islands' future.

This would include continued sheep grazing and access for responsible groups, but there were no plans for a jetty.