In 1865 the Great Hall was enlarged by the architect David Bryce, who ordered the roundel portraits from George MacCallum. MacCallum was paid four pounds per profile, a total of £60 for the set of 15 ‘Heads with wreaths’.

The portraits appear along the frieze in the Great Hall. Each of the figures in the roundel portraits is surrounded by a laurel wreath which is both an aesthetic, decorative feature, and a classical symbol which emphasises the importance of the figure depicted in the portrait.

In this portrait Thomson is depicted simply with particular emphasis on his angular cheek bone. Nonetheless, considerable attention appears to have been paid to the portrayal of small details such as his hair. Alongside the profile, a plaster bust of Thomson can also be found in the College's collection.

John Thomson (1765 – 1846)

Throughout his career Thomson played an important role in medical education in Edinburgh. In 1800 he was nominated as one of the six surgeons to the Royal Infirmary and he began to teach surgery as well as the treatment of diseases and injuries familiar to military surgeons.  In 1804 Thomson was appointed to the College of Surgeon’s new professorship of surgery, a position he held until 1821.  In 1806 he was also appointed professor of military surgery at the University of Edinburgh. However, two years later, due to criticism of his surgery by another surgeon, John Bell, he resigned from his position at the Royal Infirmary. He subsequently travelled across Europe examining different methods utilised in hospitals. In 1815 he was again in Edinburgh and made licentiate of the RCPE also in that year he was instrumental in the foundation of the Edinburgh New Town Dispensary. In 1832 he was appointed professor of general pathology at the university. He was president of the college for the term 1834 – 1836.

Thomson was also a prolific writer and his major works included: Elements of Chemistry and Natural History (3 vols.; 1798 – 1800) which ran to five editions and  Lectures on Inflammation: a View of the General Doctrines of Medical Surgery (1813) which was translated in German (1820) and French (1827) as well as being issued in America (1813 and 1817).