Based on the 1759 life-size full-length portrait by Robert Pine at Audley End, of which there is a reduced full-length in the Royal Collection described as being after Pine. The Audley End portrait was engraved in 1766 by William Dickinson as painted in 1759. Pine later said that he had taken the likeness, unseen by the King, as he was speaking to one of his attendants at the top of the great stai…