The 50 handsome reproductions and informative notes in this work form the perfect primer for the National Gallery's Leonardo blockbuster. We learn that the chilling smile of the Mona Lisa or La Gioconda (which is staying in the Louvre) may be a pun on her name, since giocondo means "light-hearted". Similarly, his pert Cecilia Gallerani petting a white stoat in unlikely fashion (which has made it from St Petersburg) is a reference to her husband's membership of the Order of the Ermine. Since they are in the Royal Collection, we will be able to enjoy drawings ranging from "The Sexual Act in Vertical Section" to "Deluge over the Sea". As Walter Pater noted, Leonardo was obsessed by "the smiling of women and the motion of great waters."