A librarian found smallpox stored inside a 19th century medical book!

On March 31, 2003, Susanne Caro found an envelope inside an 1888 Civil War medical book in the College of Santa Fe's library. On the envelope was written: "scabs from vaccination of W.B. Yarrington's children." This statement was signed by the book's author, Dr. W. D. Kelly. Just as he said, inside the envelope were scabs.

Caro contacted the National Museum of Civil War Medecine to see if they wanted the scabs. The museum's director knew that, during the 19th century, bits of scabs of patients with with mild cases of smallpox were inserted into the skin of healthy people. This helped them develop an immunity to the disease. The museum took the scabs and contacted the Armed Forces Institute of Pathology.

Researchers planned to study the scabs to learn more about smallpox and how we came to have our current smallpox vaccination.

(Source)