By far the most unusual object selected for the Green Drawing Room, this organ clock and casket probably belonged to George IV's grandmother Augusta, Princess of Wales (1719–1772).  It was intended to stand in the prime position at the centre of the window bay.

This extraordinary piece consists of an elaborately enamelled seventeenth-century Augsburg casket inset with engraved rock crystal panels, resting on a mahogany base containing an organ clock. The organ plays music composed by Handel and the casket is topped by a gilt-bronze group of St George and the Dragon, which may have formed part of Charles I's collection.