The first e-reader built in 1949

The first e-reader was neither kindle, nor kobo, nor a sony. Moreover, it was build more than 50 years before the current tablets.
In 1949, Angela Ruiz Robles, a language teacher from Spain built what she called "La Enciclopedia Mecanica" ("The Mechanical Encyclopedia"). The major motivations for such invetion were to stop children carrying heavy books and to make reading more accessible. Unfortunatly, she could not get the funding fr the project; besides, the implementation was quite mpractical for those years.
The device worked based onpressurised air, allowing readers to add different spools containing the pre loaded documents. It also had a zoom option, allowing to focus on a specific area.
The working prototype is at the "Museo Nacional de Ciencia y Technologia de La Coruña - España" ("National Museum of Science and Technology in La Coruña - Spain")

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Spanish teacher invented Kindle style tablet in 1949
Angela Ruiz Robles