It doesn't help you but perhaps it will help others - I moved recently and had a bunch of "junk" books similar to your grandfathers. By pure happenstance I fou

It doesn't help you but perhaps it will help others - I moved recently and had a bunch of "junk" books similar to your grandfathers. By pure happenstance I found out that recyclers love books because they get the highest prices for clean paper in books. They happily showed up - for free - and helped cart out several bookcases of old, obsolete tech books. It was quite a godsend.