A rare engraved print created by Paul Revere—he of the Revolutionary War “midnight ride” fame—has been found in a 19th century book at the Brown University library, according to this report by the Associated Press.

Marie Malchodi of the University Library’s Preservation Department was leafing through a donated collection of books that once belonged to physician Solomon Drowne, Class of 1773. The books in the collection showed signs of its previous owners throughout—a child’s paper cutout of two yellow roosters tucked in among the pages; even notes written in the margins about a trip to Boston to see a garden. All of which made her look even more closely through the volumes.

But she was not prepared for her find inside the back cover of The Modern Practice of Physics, by Robert Thomas, published in 1811. It was a single sheet of paper with an engraved depiction of Jesus Christ and John the Baptist entitled “Buried with Him by Baptism.” According to a report at the Brown University website :

Studying the delicate piece of paper, Malchodi was struck first by the dissimilar styles of the onlookers and village depicted in the background. Further inspection revealed something that piqued her interest even more: In the bottom right corner was the signature “P. Revere Sculpt.” Sensing her discovery might be unusually significant, Malchodi immediately brought it to Richard Noble, the library’s rare materials cataloguer, for a closer look. “I’ll never forget what Richard said. He looks at it and says, “That’s just crude enough to be him,'” Malchodi said.

Further research by Noble revealed that not only was it done by Revere, a silversmith and engraver, but it was an extremely rare engraving. According to the Brown report, “Clarence S. Brigham, in his book Paul Revere’s Engravings, characterizes it as ‘one of the scarcest of the plates signed by Revere.'”

It is one of only five copies known to exist. And many questions remain for scholars:

Why did Revere create the print in the first place? How did the Drowne family come to own it? Based on Jesus and John’s position chest-high in the water, Noble categorizes it as a theo-political cartoon depicting a Baptist ceremony. In his book, Brigham indicates that he could find no evidence that it was ever used publicly in a book or religious pamphlet. He also could find no model in any British book or periodical that Revere might have used as inspiration for this style of baptism depiction. Noble believes it may have been a one-off printing, meaning that Revere only made a few at a time to give to friends and close acquaintances who requested it, which also explains why the print is so rare.

“It appears to be an American original, by an American original. The son of French Huguenot refugees who eventually became, by all accounts, a Unitarian. The print thus marks a stage in the evolution of that aspect of Revere’s life,” Noble said.