WATERMARK ON THIN PAPER: 1/6d dull claret three WCG McCracken Imprint blocks of 4 ACSC 163z showing Progressive Deterioration of the Imprint, each with two or three units unmounted. Another technicially interesting lot. [The ACSC states that such varieties "are thought to be caused by paper folds". We strongly disagree: all three show characteristics of the plate degrading] (3 blocks)