And what is the modern day equivalent?
My dad used to buy these 'The World's Greatest' books when I was younger in the 90s and I loved them, there was a great variety of topics and it was basically small digestible tidbits that were easy for both adults and kids to read.
My favourites were the Ghosts one and UFOs one 
Is there a modem day equivalent of this series? My little boy would love some books like this (as would I!).