u/nothereyettbh

I don’t know if this is the write subreddit but I don’t know what to do. I went to an estate sale the other week and got these really, really old books, part of the Modern Medicine collection. They’re falling apart. The leather is old and every time I touch them, it looks like I just touched rust. Is there anyway to fix them and preserve the original stuff as much as possible?

There are six books in total but they all look the same or a little worse than others.