TWO paintings by one of Scotland's greatest artists, Sir Henry Raeburn, have been acquired for the national collection in lieu of more than £600,000 in tax.

The duo have been given to the National Galleries of Scotland through the Acceptance in Lieu scheme, which enables works of art to be given to public collections and offset against inheritance tax charges.

The portraits, of two seven year old boys, have been described as among the finest of Raeburn's work still in private hands.

They show the two eldest sons of Sir William Forbes, 7th Baronet of Pitsligo in Aberdeenshire, a wealthy and influential banker, art collector and patron.

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The paintings were commissioned in 1809–11, when the boys were around seven years old.

The acceptance of these two portraits settled £631,600 of tax, and come from the Forbes of Pitsligo Collection.

The galleries said that the portraits show Raeburn "at the height of his artistic powers".

Edward Harley, chairman of the Acceptance in Lieu panel, said: “These portraits were amongst the finest of the artist’s paintings still left in private hands.

"The allocation of the works to the Scottish National Gallery highlights the importance of the Acceptance in Lieu Scheme in bringing exceptional works of art into public ownership."

Raeburn was born in Edinburgh and lived from 1756 to 1823, and was the leading portrait painter of his time.

Originally apprenticed to a goldsmith, he showed artistic talent as a young man and in 1784 Raeburn moved to London and he spent some time in Italy, but returned to Edinburgh in 1787, where he began painting portraits of important contemporaries.

He was knighted in 1822.

The famous painting of the Rev. Walker skating on Duddingston Loch is also attributed to him.

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The eldest son, William Stuart Forbes (1802-1826), is shown feeding a hunk of bread to his pet, apparently a Bernese Mountain dog.

The younger of the two brothers, John Stuart Forbes (1804-1866) is shown with his arm around his dog, possibly a Dalmatian Pointer cross.

The NGS said that "the acute observation of the relationships between the boys and their dogs makes these works differ from the conventional portraits that Raeburn more usually produced, giving them much of the appeal of ‘genre’ paintings that show scenes from everyday life.

"As such, they have an exceptional status within the artist’s output and, indeed, in British portraiture of the period."

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Christopher Baker, Director of the Scottish National Portrait Gallery, said: “Raeburn’s work has enormous appeal through its technical sophistication and the empathy with which he portrayed his subjects.

"Both these achievements are brilliantly distilled in these delightful portraits.

"We are very grateful indeed to the Acceptance in Lieu (AIL) scheme for making the transfer of the paintings to the nation possible."

Clarissa Vallat, Sotheby’s Tax & Heritage Department, said: “We’re delighted to have played a part in negotiating the placement of these wonderful paintings with the Scottish National Gallery, by an artist so beloved by the Scottish nation.”