As ever, numerous people helped me in the writing of this book: if I have inadvertently forgotten anyone, I apologize profusely and will rectify that in any future edition.
Huge thanks to my agent, Nell Pierce, of Sterling Lord Literistic.
Thanks as well to my editorial team at Mulholland Books: Josh Kendall, Emily Giglierano, Helen O’Hare; my publicist, Alyssa Persons, and marketing director Pamela Brown. I am incredibly fortunate to have worked twice now with an amazing copyeditor, Susan Bradanini Betz, as well as Betsy Uhrig.
To Martha Millard, with love and gratitude for her continued support and guidance.
Dr. Elma Brenner, specialist in Medieval and Early Modern Medicine at London’s Wellcome Library, generously shared her expertise and permitted me to examine a number of incunabula as well as the Wellcome’s sole example of a book with anthropodermic binding.
I have a number of dear friends who are serious book collectors. Over the decades, they’ve shared their passion, knowledge, and secret lore with me, at used bookshops, antique stores, flea markets, conventions, yard sales, and in dark back alleys in the United States and abroad. Here’s to Joe Berlant, John Clute, Paul Di Filippo, Mike Dirda, Peter Halasz, Pamela Lifton-Zoline, the late Bob Morales, Brad Morrow, Peter Straub, David Streitfeld, Henry Wessells, and Jack Womack. I promise never to fold down the corner of a dust jacket again.
Many people read various versions of this book in manuscript and offered suggestions to improve it, including Jim Kelly, Jeff Ford, Ellen Datlow, Robert Levy, Cara Hoffman, Kirsten Holt, Nightwing Whitehead, Bill Sheehan, and Jeff Ford. Special thanks to my punk brothers in arms David Baillie and John Auber Armstrong, and a shout-out to Anthony Vincent Dominello, who caught a number of errors that no one else did, including me. Kristabelle Munson offered moral support by way of the Criterion Collection. Judith Clute again showed me parts of London I had never seen, including a peculiar boat in Rotherhithe.
Huge thanks to all my Swedish friends, who helped and encouraged me in more ways than I can name: Jan and Isabella Smedh and everyone at the English Bookshop in Uppsala; Sarah Bergmark Elfgren, Johan Theorin, Linda Skugge, Johan Anglemark, and of course Mats Strandberg and Johan Ehn, with whom I had a revelatory late-night conversation about how “It’s all code.”
Most of all, I want to thank Lotta Ekwall-Erickson and her husband, Per, who so kindly allowed me to stay with them on Gotland, the inspiration for Kalkö. Lotta read several drafts of this book, offered suggestions for place names, corrected my Swedish, and served as a guide to not just the real islands of Gotland and Fårö but their fictional counterpart.
Finally, all my love to my partner, John Clute, who has shared his life and library with me for the past twenty-six years and never tires of my questions about books.