This charming portrait is by the accomplished late-seventeenth century/ early 18th century portraitist, Johann Kerseboom, who initially worked in Germany before coming to England in the 1680s with his uncle, the artist Friederich Kerseboom. He set up a practice in London as a painter of portraits, where he met with greater success than his elder relative. A number of his works were engraved in mezzotint, of which eight are known. Though the postures and designs of Johann Kerseboom’s portraits often follow the formulaic patterns first seen in the works of Sir Peter Lely and Sir Godfrey Kneller, the characterisation of his heads have an individuality all their own. Collins Baker remarked that they have a ‘temper of… a certain austerity and sadness… marked characteristics that (he)… found in the work of not other painter’.2 He is best known for his portrait of Robert Boyle, which became the standard image of the scientist.