A cased gem set desk / travelling timepiece engraved Callow of Mount St, Mayfair / London, early 20th century Square translucent agate frame, with ruby mounted bands to each corner, centred with a circular signed dial, with Roman numerals, to the reverse an unmarked silver-gilt wire-work scroll easel, the movement with integral winding key, contained in original fitted travelling case, height 9cm. For further information on this lot please visit Bonhams.com For further information about this lot please visit the lot listing