I M Chaney Antique Furniture has dated this piece to the 18th Century.
by J. & P. Knapton 1746, 1744, & 1745 respectively; and “Charles Earl Of Sunderland”, “John Duke Of Argyll And Greenwich” & “Robert Earl Of Orford” by Houbraken (the latter two possibly later)
Measuring
Engravings measure 36 x 23 cms
Frames measure
Height 52 cms
Width 37 cms
Depth 2 cms
Condition, good overall, Duke of Marlborough with some bleached staining please refer to photo
I M Chaney Antique Furniture has dated this piece to the 18th Century.
You can view the stock and full dealer information on the I M Chaney Antique Furniture Profile Page