H.P. Lovecraft's The Shadow Out of Time

Just because one lives in Arkham—just because one teaches there at Miskatonic University—it doesn't mean one has any interest in the occult—in the abnormal. That was always the view of Nathaniel Wingate Peaslee, a respectable professor of political economy. Until that one Thursday in 1908, when Professor Peaslee suddenly began to see in front of him not his students in their lecture hall, but strange shapes inhabiting a grotesque chamber. He collapsed unconscious, and when he awoke, he was strange...very strange. (Source: Dark Horse)