essay Block of Four 1921 "NINE/PIES" on 1a. essays, four marginal blocks of four (three from the top left corner) and a single showing four different essay surcharges, fine; also a range of the issued stamps including a vertical pair (toned) and three singles (two toned) showing surcharge double, interpanneau blocks of 49, 32 and 8 (used), an interpanneau vertical strip of eight and two vertical pairs showing a total of eight "NINE/NINE" errors and twelve "PIES/PIES" errors; mostly fine. An interesting study