Haunted Campus: UW Madison Ghost Stories

The Badger Herald has gathered an spooky list of hauntings on campus. Wisconsin Union Theater, Science Hall and Memorial Library are among the supposedly haunted.
Memorial Library is also mentioned by Britannica Blog in their list of haunted libraries. From the list of Midwest libraries:

Madison, University of Wisconsin, Memorial Library. The ghost of English professor and novelist Helen Constance White (1896-1967) has reportedly been seen floating through the library stacks. One Christmas break when the library was closed, a student library assistant doing catch-up work in the reference stacks heard someone whisper “Sally Brown” when no one was around.

Why would Helen C White be haunting Memorial? Would it make more sense for her to be over at College Library (which is in Helen C. White Hall)? And who is this mysterious “Sally Brown”?
The Badger Herald has a bit more:

According to a brief catalog of library ghosts by Katie Buller Kintner, a former shelver at Memorial Library, a mysterious whispering of this name was heard during one of Kintner’s shifts at the library over Christmas break. Upon checking the alumni records, Kintner and her colleagues found no such name registered, and it is believed that Brown may have been one of the library’s former cataloging assistants whose pictures hang upon the walls.

Being the librarian that I am, I went looking for more on this. I turned up what I assume is Katie Buller Kintner’s original column about library ghosts which reveals that the “Sally Brown” library in question is the SLIS Library, not Memorial. And she wondered whether “Sally” might be one of the early 20th century library school students depicted in the photos which adorn the library school.
I also found that there was indeed a “Sally Brown” who attended UW Madison in 1976.
Update:  For more on the spooky history of Science Hall, see this 2016 piece from the Nelson Institute for Environmental Studies.