This and another portrait of Thomas by an artist in the school of George Romney were presented to the RIBA as portraits of Robert Adam and his elder brother James Adam and these attributions remained unchallenged until the mid-twentieth century. The identification with William Thomas was made because the sitter in the other portrait (and they are clearly the same man) holds a plan of Willersley Castle, Derbyshire, Thomas's most important work.
Where to see this painting?
RIBA Library Drawings and Archives Collections
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