Cassiano dal Pozzo's print collection was unique in its scope and organisation. Some 3,000 prints are known, in nine albums and many loose impressions mainly divided between the British Library and the Royal Library at Windsor Castle. Cassiano (1588-1657) and his younger brother Carlo Antonio dal Pozzo (1606-89) did not commission printmakers to engrave plates (as they did drawings), buying instead what was available from the flourishing printmaking...