This time of year my mind turns to ghost stories.
“Professor Kate” was written by Margaret St Clair, a prolific author working in the pulp magazines, mainly science fiction and weird fiction. She lived with her husband in Berkeley, California, and they became Wiccans. Both she and her husband were successful writers, and of Margaret author Ramsey Campbell has said, “she is yet to be fully appreciated.”
This short tale is from Weird Tales, January 1951. I found the scans in the Internet Archive. The contents were originally copyright © 1950 Weird Tales.