RARE 1873 ENGLISH MADE "GLASGOW/159" DUPLEX ON PIECE. Small piece with 1d pl.160 (SG43) lettered IC, centred to lower left but tied superb strike of the GLASGOW/159 duplex with larger circle (23mm) OC 18 73. This rare duplex is shown in the English proof books of 6/5/73 and not known in the Kirkwood proof book. First example of this cancellation we have seen. (Ref 113714).