It appears that he was recommended by Lorenzo de'Medici to Lodovico il Moro, Duke of Milan, probably for the very purpose of executing this statue. However that may be, it is now certain that in 1483 he was commissioned by the Franciscan monks to paint a picture of the Virgin and Child for their church of the Conception, and that between 1491 and 1494 Leonardo and his assistant, Ambrogio di Predis, petitioned the Duke for an arbitration as to price. This was the famous _Virgin of the Rocks_, now in the Louvre, and the similar, and though not precisely identical, composition in our National Gallery is generally supposed to be a replica, painted by Ambrogio under the supervision of, and possibly with some assistance from, Leonardo himself. Between 1495 and 1498 Leonardo was engaged on the painting of _The Last Supper_. In the Forster Library at the Victoria and Albert Museum is a notebook which contains his first memoranda for the wonderful design of this masterpiece. At Windsor are studies for the heads of S. Matthew, S. Philip, and [Illustration: PLATE V.--LEONARDO DA VINCI THE VIRGIN OF THE ROCKS _National Gallery, London_] Judas, and for the right arm of S. Peter. That of the head of the Christ in the Brera at Milan has been so much "restored" that it can hardly be regarded as Leonardo's work. Vasari's account of the delays in the completion of the painting is better known, and probably less trustworthy, than one or two notices of about the same date, quoted by Mr H. P. Horne, in translating and commenting on Vasari. In June 1497, when the work had been in progress over two years, Duke Lodovico wrote to his secretary "to urge Leonardo, the Florentine, to finish the work of the Refectory which he has begun, ... and that articles subscribed by his hand shall be executed which shall oblige him to finish the work within the time that shall be agreed upon." Matteo Bandello, in the prologue to one of his _Novelle_, describes how he saw him actually at work--"Leonardo, as I have more than once seen and observed him, used often to go early in the morning and mount the scaffolding (for _The Last Supper_ is somewhat raised above the ground), and from morning till dusk never lay the brush out of his hand, but, oblivious of both eating and drinking, paint without ceasing. After that, he would remain two, three, or four days without touching it: yet he always stayed there, sometimes for one or two hours, and only contemplated, considered, and criticised, as he examined with himself the figures he had made."