Item Title:
Framed and glazed proof sheet of 120 one penny 'Mercury Air Mail' stamps for 1923 London International Stamp Exhibition held at the Royal Horticultural Hall from 14th to 26th of May. Photograph in recess depicting a dandy roll with the intended watermarks. Label reads: 'PROOF SHEET OF AIR MAIL STAMPS IN/ANSWER TO THE GREAT DEMAND OF THE PERIOD./AND THE ABOVE PHOTOGRAPH SHOWING THE/INTENDED WATERMARKS. FIRST SINGLE AEROPLANES,/SECOND MULTI AEROPLANES. BY EDWIN AMIES.' On the back is handwritten: