(Maria) (b Milan, before 1592; d after Oct 4, 1648). Italian collector. He is best known for his collection of works by Leonardo da Vinci. He owned 12 small Leonardo notebooks as well as the Codex Atlanticus, which he donated to the Biblioteca Ambrosiana, Milan, in 1637, and several cartoons, among them the Virgin and Child with St Anne, known as the Burlington House Cartoon (London, N.G.), and a standing Leda (untraced). Inventories of the Arconati collection and Edward Wright’s travel diary (1730) reveal that he had also owned the 11 coloured chalk drawings (e.g. Chapel Hill, U. NC, Ackland A. Mus.; Melbourne, N.G. Victoria) after Leonardo’s Last Supper (Milan, S Maria delle Grazie), attributed to Giovanni Antonio Boltraffio (Brown), and also paintings by Raphael and Andrea del Sarto. During the 1630s Arconati corresponded with Cassiano dal Pozzo, who was trying to procure Leonardo manuscripts for the Barberini library and to prepare compilations of Leonardo’s writings for publication. Passages on mechanics, hydraulics, light and shadow and perspective and additional chapters on painting were collected into ‘treatises’ by Arconati with the help of his son, ...