From: http://commons.wikimedia.org/wiki/File:Flammarion.jpg The Flammarion woodcut is an enigmatic wood engraving by an unknown artist that first appeared in Camille Flammarion's L'atmosphère: météorologie populaire (1888). The image depicts a man peering through the Earth's atmosphere as if it were a curtain to look at the inner workings of the universe, comprising the classical "Seven Heavens" of diverse tradition and literature. The caption translates to "A medieval missionary tells that he has found the point where heaven and Earth meet..."