Sir Walter Scott and Robert Burns

It doesn't look very prepossesing, does it? And yet this house - converted to flats in a tiny side street in South Edinburgh - was Sciennes House, the home in the eighteenth century of Professor Adam Ferguson, Scottish philosopher, social scientist and historian. There were famous "salons" held here - bringing together the great giants of the Scottish Enlightenment.

One evening in the winter of 1786/87 such a gathering included Dugald Stewart the philosopher, Adam Smith the economist, and James Hutton the geologist - with many others. The company was graced by the presence of the ploughman poet, Robert Burns, lionised in Edinburgh society at the time.

Burns was moved by a sentimental print illustrating a poem entitled 'The Justice of the Peace'. When he asked who had written the original poem, only Scott - present as a 15 year old friend of Ferguson's son - was able to tell him it was by John Langhorne. For this, Scott received a look and word of thanks that he would always remember.

Charles Martin Hardie captured the moment in this famous engraving.