I would worry if I tried to sell copies, but if I scanned pages from the book and posted them I don't think they'd send me to jail or even fine me for copying a 1931, out of print textbook. At most "they" would make me remove them from the site. I'll get the appropriate pages scanned, put them in a PDF and post them, and we'll see what happens. I'll include a disclaimer stating that I take sole responsibility for it.