See Frank Falkner, The Wood Family of Burslem (London, 1912), p. 16, pl. IX, illus. no. 37. Here the author notes that the portrait 'shows a lifelike expression of the American philosopher, who in 1757 met with such appreciation in England.' Also compare the example sold in the Collection of Mrs. J. Insley Blair, sold Christie's, New York, 21 January 2006, lot 502.