The overmantel mirror, is designed in the George II 'picturesque' manner popularised by Matthias Lock's, Six Sconces, 1744. The serpentined frame is flowered and trellised and enriched with shell-scallops and acanthus-wrapped reeds. The nature-deity's antique fretted 'shell' cartouche is displayed in its pediment, while the reeds of its inner pilasters display the bull-mace badge of the Arcadian deity Pan. Thomas Chippendale included related tripartite frames in 'Chimney Piece' patterns illustrated in his Gentleman and Cabinet-Maker's Director, 3rd ed., 1762. The shell badge was formerly wreathed with flowers and incorporated a central quatrefoil.
The mirror formed part of the collections of the Viscounts Midleton of Midleton, Peper Harow, Surrey and was sold by George, 10th Viscount Midleton and 2nd Earl of Midleton (d. 1979). It may have been supplied to George, the 3rd Viscount (1730-65) who commissioned Sir William Chambers to build the present house, built in the lifetime of his son between 1765-68. If the mirror is original to the house, it would have been supplied to George, 4th Viscount Midleton (1754-1836), who succeeded to the estate in 1765 and completed the building of the house.