Found this in the BMJ. Not sure what it has to with illustration but think it is great. About bootleg music during the cold war era in the Soviet Union. X-ray plates were used and the grooves cut into the disc. They were called 'bones" or "ribs".
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Handmade Fabric Book Covers
Working on some book covers for a print fair in May. Hopefully a good way to use some pieces of work that have been neglected. Think they work quite well