1907/08 COVER DUO INC. WITH RARE TOWER OF LONDON CACHET - Aug. 1907 env. (flap faults) to Holborn with rare pictorial "TOWER OF/LONDON" arched frame cachet and "LONDON E. C. OFFICIAL PAID/5" alongside; and Apr. 1908 env. to Wimbledon with crowned double oval "ROYAL/MINT" cachet at lower left and "OFFICIAL PAID/LONDON E." at right, embossed Royal Mint 'seal' on the flap. (2) (Image)