Engraving from "Essai sur L'Instruction Des Aveugles" [Essay on the Instruction of the Blind] by Sebastien Guillie, Paris, 1817. The image depicts the equipment used to teach reading and writing to blind students. On the top left-hand side is a board with eight horizontal grooves; one groove contains letters forming the word "dieu" (god). Below this board are enlarged examples of three wooden letter tiles. On the right-hand side is a slanted wooden table with compartments containing different letters.