John Fuller, known as ‘Mad Jack Fuller’ due to his eccentricity, was a wealthy land owner and sometime MP for Sussex, the coast of which can be seen in the background of the portrait. His parliamentary career was colourful, even by the standards of the time: in one notorious incident, presumably while overtired and emotional, he was dragged from the House for swearing and calling the Speaker ‘the little insignificant fellow in the wig' and spent two nights in Parliament's prison. Fuller was also a major patron of the arts and sciences. He commissioned and collected works by J. M. W. Turner and provided financial support for the Royal Institution. This latter included endowing two professorships, creating the chemistry chair especially for Michael Faraday.