It certainly was when I was younger. I may have to reread them to see if they hold fast in adulthood. I'm guessing they will as long as one bears in mind that it revolves around science theory written in the 1930s. Some of it was pretty advanced thinking for it's age.

I'm pretty sure I had doubles of at least two books via gifts. If I find them, they are yours.

With great power comes Awesome irresponsibility.