Comment by IG_Semmelweiss

Similar story : Growing up , my mother bought us an encyclopedia set (in Spanish) hardcover set with blue covers , where each volume was named after a question, and there were at least 8 with names like:

What? When? How? Why? Who? Where? etc

The questions would range from the "how do planes fly" , to "who discovered gunpowder?". They would have illustration, which was super helpful to picture steam power, and the Cretacean period duration relative to other periods, etc. It was all in color so I suspect they have aged well. I remember coming back to certain questions over and over. Some that I still remember - "When did the universe begin?" "What happened to the dinosaurs?".

IN short I cannot recommend this set enough. I tried to google, I'll need to come back and post it once I find the original that is hanging out at a relative's library.