Another signed Bradbury first:
Bradbury, Ray. That Son of Richard III: A Birth Announcement. Roy A. Squires, 1974. First edition chapbook original, #LXIII of 85 the signed “Autograph Edition,” a Fine- copy with just a trace of wear at tips, in a Near Fine+ original Autograph Edition publisher’s envelope with slight age darkening at edges and slight bumping at tips. Chalker/Owings, page 589. Bought for $50 (marked down from $80) on eBay.
Unnoted in Chalker/Owings is the fact that two of my three copies have a “PZ” glyph inscribed on the lower right side of the introduction page, just barely visible in the scan.
This is my third copy of this Bradbury chapbook, following an association copy inscribed to Lord John press founder Herb Yellin and an unsigned copy of the “ordinary” edition. The ordinary copy has this, but the one inscribed to Yellin doesn’t. Bit of a mystery…
Edited to add: Mystery solved! I checked with fellow bookseller (and Old Earth Books publisher) Mike Walsh to see if he could solve the glyph mystery, and he directed me to bookseller Terrance McVicker of Bats Over Books, who had the answer:
The “PZ” you note in your query is actually “ZN,” printed on top of each other, if you turn it sideways. It stands for “Zerkall Nideggen.” Nideggen is a Japanese paper, but Zerkall was the German manufacturer. I think what Zerkall did was buy the pulp paper from Nideggen, then process it in their factory.
What your seeing is the Zerkall Nideggen watermark. The sheet before cutting, measured 24″ X 36″ and there was a watermark in the lower right-hand corner of the full sheet. Which meant that, when the sheet was cut to quarto size, only one out of eight pages would have the watermark. Printers usually try to get one watermarked page per book/booklet, but it doesn’t always work out that way.
Thanks for the info!