A Scottish businessman has donated £1m to help fund the refurbishment of the National Museum of Scotland.
Former nuclear physicist Dr Walter Scott's donation to the museum Edinburgh's Chambers Street brings the total funds raised to more than £44m.
Another £2m is needed for the revamp, which will see the creation of 16 new galleries and education facilities.
Dr Scott's donation will fund the Discoveries gallery, which will be at the heart of the refurbished museum.
The former scientist owned Edinburgh-based investment management company Walter Scott and Partners until 2006, when he sold to US-based Mellon Financial Corporation.
As a physicist, Dr Scott said he was inspired by the museum's collections reflecting the scientific achievements of Scots, including those of Sir Alexander Fleming.
He said these told "extraordinary stories of Scottish engagement with the world".
"I have been amazed by the ambitious vision to transform the Victorian Royal Museum building and the tremendous progress to date," he said.
"National Museums is returning to us one of the jewels in Scotland's architectural crown. I am delighted to help make this happen."
Dr Gordon Rintoul, director of National Museums Scotland, described Dr Scott as a "great supporter" of its work.
He said: "We are tremendously grateful for his generous gift which will allow us to fulfil our aspirations for a major gallery in the National Museum of Scotland."
About half the museum complex is currently closed for refurbishment, including the Victorian main hall.
The museum is scheduled to reopen in the summer of 2011.