5997028 Layout of the keys of the monumental organ of St Peter\'s Basilica, Rome (litho) by Spanish School, (19th century); Private Collection; (add.info.: Layout of the keys of the monumental organ of St Peter\'s Basilica, Rome. 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.