5996986 Formation of the layers of the Earth\'s crust up to the Cretaceous Period (colour litho) by Spanish School, (19th century); Private Collection; (add.info.: Formation of the layers of the Earth\'s crust up to the Cretaceous Period. Illustration from El Mundo Ilustrado Biblioteca de Las Familias (The Illustrated World Library of Families) (Biblioteca Ilustrada de Espasa Hermanos, Barcelona, c1880).); by Look and Learn.