Dating printing wood blocks
The challenge with color printing, where each color requires a separate block, is how to prevent misalignment and thus guarantee accurate registration during the printing of multiple colors.
Block-cutters developed a system that involved cutting two registration marks (引き付け見当) at the bottom left corner Figs.
However, different from the books themselves, which have been comparatively well studied and documented, one has the sense that the printing blocks employed in their production have been left behind in our appreciation of Edo-period publishing culture.
Moreover, with the printing positions (stops) set to prevent horizontal offsetting or vertical slippage there would be no need to allocate extra margins on the paper.Sadly, many surviving printing blocks no longer have these.The printing blocks owned by the Kyoto publisher Hōzōkan (法藏館)—reportedly stored in the same way since the Edo period Fig.7—shows that the printing blocks were stacked and stored flat.
Stacking the blocks in this manner meant that the varied over time, and an examination of the ends of a printing block helps to determine when the printing block was made, or at least gauge its relative age (newer or older).
Aligning the paper with the printing blocks must have been necessary to produce sheets ready for the binding process.