After 200 years in unmarked grave, giant of Enlightenment to be celebrated again

He played a key role in helping Edinburgh earn its famous label as the "Athens of the North".

• A portrait of the scientist, mathematician and philosopher John Playfair by another great, Sir Henry Raeburn

But the grave of one of the leading figures in the Scottish Enlightenment has lain unmarked in the capital for almost 200 years.

Now a campaign is under way to recognise the final resting place of John Playfair, the celebrated scientist, mathematician and philosopher whose adopted son William went on to become one of the city's best-known architects.

Heritage chiefs in the capital have vowed to recognise the contribution of Playfair, who was also a major influence on James Hutton, the 18th century Edinburgh scientific pioneer widely considered the "father of modern geology".

As president of the Astronomical Institution of Edinburgh, he instigated the creation of the first Greek-style building on the city's Calton Hill.

A striking memorial to John Playfair, designed by William, who was actually his nephew, was erected on Calton Hill after his death in 1819, the year after the New Observatory was built atop the beauty spot.

Now supporters hope to erect a permanent memorial at his graveside in the nearby Old Calton Burial Ground to raise awareness of his contribution to the city.

• John Playfair: making history

The historic graveyard, which dates back to 1718, is home to high-profile memorials to the likes of philosopher David Hume, publisher William Blackwood and architect Thomas Hamilton, while a statue of Abraham Lincoln has pride of place in the cemetery in memory of the Scottish soldiers who fought in the American Civil War.

It emerged last year that five city cemeteries - including the Old Calton Burial Ground - had been placed on an international "at risk" list for historic graveyards. The inclusion of the sites came after the city council put them forward for consideration, admitting many had been neglected and had become home to drug users and anti- social behaviour.

A new graveyards trust has been set up to oversee moves to restore run-down graveyards, repair dilapidated monuments, and encourage more visitors to the historic burial grounds.

Cliff Porteous, a retired geologist who runs tours of Calton Hill, is working with Edinburgh World Heritage to get the Playfair campaign off the ground.

He said: "As a geologist, John Playfair is a hero of mine, particularly for his Illustrations of the Huttonian Theory of the Earth.

"I take people over Calton Hill to the monument built by his nephew William but when a tourist asked to be taken to his grave I could not locate it.

"I tracked it down to the Old Calton Burial Ground, where his name is listed on a noticeboard at the entrance.Eventually, after days of research it was confirmed that John Playfair was buried in an unmarked grave adjacent to the philosopher David Hume's monument.

"The lair has three walls with a small step all open to the heavens, but nothing to tell people that this remarkable figure in Scotland's and Edinburgh's history - an important mathematician, astrologer, philosopher and geologist - is buried there."