Tissue-paper overlay maps
From Graphis Diagrams, a dreadful, dated book from the 1970s. The credit reads ‘Experimental digital map of Africa. It consists of four transparent sheets (of which we show only two).’ How’s that for unclear on the concept?
The whole thing doesn't work anyway, as the symbols and type on underlying pages compete with the page you're actually trying to read.
Claimed original credit: Graphic Design Magazine