Three quarter length portrait. The sitter wears a red gown and white turban like nightcap. His left arm rests on a table beside an open book. Behind his right shoulder is a telescope; in the first draft the place of this had been occupied by a rod in Robison's left hand and this can still be traced under the paint of the final version. The background is dark brown. The colour is brilliant and impressive, the handling powerful and the brushwork, with its broad paralellograms, is almost impressionist in technique. Armstrong has described it as one of the most outstanding of Raeburn's portraits, marking the end of the master's second manner. The painting was engraved by Turner. There is a second portrait of Robison by Raeburn in the rooms of the Royal Society of Edinburgh. Both are striking examples of the artist's work.