I know the books you are talking about. I received them as a child, so that would make them about 40 years old. I can't believe I'm that old! I loved them. One book a month would arrive in the mail and it was very exciting at the time. I gave the books away a couple of years ago after concluding that I never would bother with them again. The pictures are all black and white and many items were outdated although the bulk of the entries are timeless. If you go to Abebooks.com and search for them, you will find them listed. The books go for a dollar a volume. They are well written and you probably would enjoy looking through them. Your in-law would probably like the idea of the books (that maybe gave him pleasure) finding a good home. Enjoy!

Thanks for the input , prairiefox. I have to start rationing my self at some point becuase I'v e almost collected more books than I have the space to shelve!
I will check out Abebooks.com....