Years ago when my bitter half and yours fooly had limited resources (i.e., no TV, etc.), we spent most of our leisure time in a small branch of a local public library. Our tastes were more or less hit or miss, but there was one particular non-fiction book that is vexing me. That is, I'm driving myself crazy -- er, crazi-ER-- in that I can't remember the title or author!
It is most likely out of print by now, but it was a non-fiction book about books, namely New York Times best-selling novels which, along with their authors, had fallen into obscurity. I'm fairly certain it was hard-cover, and a trade book by a commercial publisher as opposed to a Ph.D dissertation. The author chose one best seller per decade and wrote about it and its author.
I can recall two of the neglected works covered. The first was from 1924 The Green Hat by Michael Arlen (the earlier Michael Arlen, not the one born in 1930.) The other one I vaguely recall was a science fiction novel from the 1930s or 1940s about the catastrophe of the Moon falling into the earth. Can't remember the author (it wasn't Heinlein or Asimov or Clarke) and of course not the title. As I said, the books scrutinized had been forgotten.
But I wish I could remember the title and author of this study!
By the bye, there are some websites about neglected classics, including the one managed by Brad Bigelow
www.neglectedbooks.com