Thanks for the replies. I have already scanned them through the glass (the long ones took two, then pieced together) the results surprisingly good. I thought about soaking, but I'm concerned that if it doesn't free them, then what? If I let the whole thing dry, then I'm worse off. I guess I could try some water with PFlo just on the area and keep it wet, maybe with a wad of cotton over the area for a couple hours, then if it doesn't work, not much lost.
It is fiber paper, single weight, my guess from the 40s or 50s, and the prints were originally ferrotyped.