The Fern Watson Library is located at the end of the museum opposite the office. It is named for the long-time society member who left funds to establish the first museum located in the old train depot east of town. She was the daughter of Doctor Watson who, as a pre-teenager, sat on Abraham Lincoln's lap on the stage coach ride from Ashley to Mount Vernon. The stage was full with Abe's associates as they headed for the all important Illinois vs Illinois Central Railroad trial at the then-new Supreme Court Building. Young Watson was so inspired by Abe's many tales that he never forgot the adventure and the story made it's way into the history books. An indication of the Lincoln connection is the set of six Lincoln pictures visible through the library door glass.
The library is home to the documented history of the society plus many other one-of-a-kind Jefferson County records.
A recent addition to the library shelves is the set of sixteen binders containing records by township of the 144 one-room schools that were the centers of primary education a century ago. The binders contain much historical information and document some of the efforts of a county-wide program led by society members Larry Periman and Sharon Nichols to erect a sign at each original school building location.