Short answers, pulled from the story.
Cornell University Library holds one of only five known handwritten copies of the Gettysburg Address by Abraham Lincoln. It is the only copy that is privately owned, and it is the only one accompanied both by a letter from Lincoln transmitting the manuscript and by the original envelope addressed and franked by Lincoln himself.
As of 2014, Cornell University Library holds over eight million printed volumes and more than a million ebooks. It is ranked the 16th-largest library in North America by volumes held and the 13th-largest research library in the United States by both titles and volumes.
arXiv is an eprint archive originally created at Los Alamos National Laboratory by Paul Ginsparg. Cornell University Library provides stewardship and partial funding for arXiv, which has changed the way physicists and mathematicians communicate by making preprint publication viable and widely used.
The Rose Goldsen Archive of New Media Art is a research repository for new media art founded in 2002 by Timothy Murray at Cornell University Library. It is named for Rose Goldsen, a Cornell Sociology Professor and avant-garde critic of mass media. The archive holds multimedia artworks, videotapes, and born-digital materials tracing new media art from the 1960s to the present, and is one of six international digital art archives dedicated to preservation and documentation strategies.
Cornell University Library holds first editions of Charles Darwin's Origin of Species (1859), Jane Austen's Pride and Prejudice (1813), the Book of Mormon (1830), and Thomas Hobbes's Leviathan (1651). The library also holds a copy of John James Audubon's The Birds of America, one of only 120 complete sets known to exist.
The Department of Rare Books at Cornell was founded in 1951. It was absorbed into the Rare and Manuscript Collection in 1992, the year the current physical location in the Carl A. Kroch Library opened. The collection dates back to the university's founding in 1865 and now holds more than 500,000 printed volumes and 20,000 cubic feet of manuscript materials.