Colleen Theisen

The University of Iowa library contains more than 4,000 miniature books, all measuring fewer than three inches in either height, width, or both. Three inches is not a lot for a book, but three inches is outright capacious when compared with a little red bug of a book, one of the smallest objects in the entire collection, measuring 0.138 inches square and 0.04 inches thick.

Based on the cover, library staff assumed the little book was a Bible, or at least some part of one, and a photograph taken through a magnifying glass and cleaned up on Photoshop confirmed this suspicion. But everything else about it was unknown. Librarian Colleen Theisen, who found it in a box marked "microminiatures," calls it the "most perplexing" of the miniature collection: a book so small it could not be read by the naked eye. What was it? Who made it and when? Whatever clues its text contained were locked between its tiny binding.

On Monday Theisen highlighted the mysterious book on the Tumblr and Facebook page of the library's special collections division, which brought the volume to the attention of Giselle Simón, the library's conservator. Simon suggested putting the library's new microscope to use.

Colleen Theisen

Theisen, with the help of Candida Pagan, a student in the university's Center for the Book, carefully cracked open the pages and put it under the microscope. Sure enough, there was the publisher's imprint: Toppan Printing Co., LTD. (The page was, Theisen writes in a post about the discovery, a bit damaged from earlier attempts to read it.)

Colleen Theisen

Working backward, Theisen was able to piece together more about the book's provenance. It had originally been part of a two-book set, sold at the World's Fair in New York in 1965. At the time, they tiny book was thought to be (and marketed as) the world's smallest book, though that record has since been broken. The "larger" sibling book (measuring a hefty 1 3/8" by 1 3/8" and thus still, technically, a miniature) was also part of the library's collection, though somehow over the years the two items had been separated.