Two sets of knowledge recently tapped into;
I am jealous of my co-worker who is processing the papers of John Becker, a modernist composer of the early 20th century. In the papers is a long line of correspondence from Henry Cowell, including letters from San Quentin. I was able to see some programs from concerts that Cowell put together for the prison band thanks to the kindness of Warden Court Smith. There is surely much more information that she gets to cruise through, regarding the personal relationships with Henry Cowell and Charles Ives, and Cowell's falling out with Ives regarding the jail stint, and the sex with young men thing. A lot of the materials were to be closed for 10 years after Cowell's death, and I am not sure how much past researchers of Cowell have actually taken witness to these exact materials as they have been dwelling in the netherworlds of unprocessed collections.
And yesterday, through research, I came across the Davies Project
at Princeton University, which has a quick list type database of historical libraries in the United States before 1876. It shows you collection sizes by location and type, with data culled from the work of a Prof. Haynes McMullen, emeritus, University of North Carolina between 1960 and ca. 1995. It's very inspiring.