By the close of the eighteenth century, learning to read and write became closely associated with learning about the material world, and a vast array of games and books from the era taught children how to comprehend the physical world of "things." Examining a diverse archive of popular science books, primers, grammars, toys, manufacturing books, automata, and literature from Maria Edgeworth, Jean-Jacques Rousseau, and Anna Letitia Barbauld, The Education of Things attests that material culture has long been central to children's literature. Elizabeth Massa Hoiem argues that the combination of reading and writing with manual tinkering and scientific observation promoted in late eighteenth- and early nineteenth-century Britain produced new forms of "mechanical literacy," competencies that were essential in an industrial era. As work was repositioned as play, wealthy children were encouraged to do tasks in the classroom that poor children performed for wages, while working-class children honed skills that would be crucial to their social advancement as adults.