James Ferguson, the son of a Banffshire farmer, taught himself astronomy by lying on his back in his father's fields and mapping out the heavens - hence his nickname. Ferguson rose to become one of the most respected and inspirational astronomers of his time but because of his humble origins, had to support himself by various means, one of which was to create portrait miniatures, for which he charged ten shillings. He used a medium called plumbago or graphite, which was ideal for fine detail. The sitter in our portrait is unknown but most of his subjects came from Edinburgh. Examples of Ferguson's work can be found in the Science Museum.