Chatsworth's Old Master stroke: unseen drawings revealed – in pictures

Leonardo da Vinci, Leda and the Swan (c 1503-4) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Rubens, A Peasant Girl Churning Butter (c 1620-35) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Rembrandt, An Actor in His Dressing Room (c 1638) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Annibale Carracci, A hunchback boy (c 1580-90) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Titian, Landscape with Riderless Horse Pursued by a Serpent (c 1525) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Jan Gossaert, or Mabuse, Adam and Eve (c 1589-90) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Giovanni Francesco Barbieri, or Il Guercino, A River in Flood, and Peasants with Axes and Other Tools (by 1623) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Claude le Lorrain, Landscape with Christ Preaching the Sermon on the Mount (c 1656) Photograph: Diane Naylor/Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Albrecht Dürer, The Virgin and Child with the Infant Saint John (c 1518) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Anthony Van Dyck, Pieter Brueghel the Younger (c 1636) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Raphael, Seated Woman Reading with Child (c 1512-14) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees Pieter Brueghel the Elder, View of the Ripa Grande (c 1552-1553) Photograph: Devonshire Collection, Chatsworth / Reproduced by permission of Chatsworth Settlement Trustees