Yes, the Williard Library ghost is quite famous among bibliotechal cognoscentii. Or at least among such in Indiana.

If you've every had to "overnight" in an old library....

During my early undergrad years, the library was in a wing of the college that included, above the library, a performance hall. The hall was one of those wonderful old kind with a barrel-vaulted ceiling, and the acoustics were so good that the music department tuned there even though the hall itself hadn't been used for 50 years or more. We'd hear them doing this from time to time.

One night, my friend Peggy was working late and heard cello music. Since it was nearing midnight, she went up the back stairs to see who was there. When she opened the door to the stage, the lights went out and the music stopped. Her flashlight showed no one, and no disturbance of the dust on the stage surface.

The old wing is gone now, torn down.