Alvin James - Leonardo Da Vinci: A Magnificent Failure
By May of 1504, Leonardo's contract was revised due his employer's concern with his lack of progress. This new contract required that he first complete a cartoon of the battle scene (now lost) by February (Orosz). Large rooms were required for Leonardo to draw the full-scale cartoon. It is believed that the cartoon was completed at or around March of 1505. Leonardo actually began painting "on the sixth day of June, 1505, a Friday, on the stroke of 13 hours… and when I raised my brush a storm broke out…[the sheets of the cartoon fell apart], there was heavy rain until evening and it was dark as night" (Field 316). This may have been an omen of the misfortune that was to come.
The majority of the murals that were successfully done during the Renaissance were created using a technique called fresco (Italian meaning "fresh"). There are two main types of fresco, 'dry' fresco (fresco secco) and 'wet' fresco (fresco buono), with wet being the more commonly utilized form (Field 202). In fresco buono a fresh wet layer of plaster is applied to a prepared wall surface and the pigments used in the actual painting are soaked in water to facilitate their absorption into the plaster. A chemical bond forms between the paint and the wall surface as the paint dries and the two are permanently fused together. This technique allows the paints to last as long as the plaster remains intact. One of the down sides to this method is that the artist must know exactly what he is doing, because substantial corrections can not be made as a result of the rapid drying of the pigments. Fresco is also vulnerable to damage from exposure to high humidity. The color range in Fresco is much more limited than that of oil paintings with darker colors being especially difficult to implement. The difficulty associated with implementing dark colors onto fresco murals is believed to have heavily contributed to the brightness of Renaissance murals.
Leonardo's mentor, Verrocchio, never learned the fresco technique and as a result was not able to teach it to Leonardo. Consequently, when Leonardo painted his Last Supper mural (1495-97) he devised a new mural technique more consistent with his style that incorporated oil. This technique had advantages over the orthodox fresco technique in that it allowed him to work at a slower pace and make alterations as needed (Field 211). Unfortunately this medium did not wear well and his masterpiece soon began to wear away. In fact today, little of Leonardo's original work on the Last Supper remains.
By 1505 Leonardo was already aware of the fact that his Last Supper was beginning to show signs of deterioration. Despite this observation he continued to deviate from the more durable orthodox fresco technique while working on the Battle of Anghiari. In this case he used a method that involved mixing pigments with wax. This mixture, when heated, bonded to the wall (Field 317). It is believed that Leonardo derived this method from studies of the ancient method of encaustic (translation: fixing by heat) he encountered in a book by Pliny. Leonardo found it very difficult to dry the paint using this technique. Scholars theorize that this was the result of the types of oils he used and the fact that when flame was used to dry it, the colors at the top would run. Scholars have pointed out that Leonardo must have missed a crucially important part of Pliny's instructions for the encaustic technique: "Those among the colors which require a dry, cretaceous coating and refuse to adhere to a wet surface are purpurissum, indicum, caeruleum, milinum, orpiment, appianum, ceruse. Wax, too, is stained with all of these coloring substances, for encaustic painting; a process which does not admit of being applied to walls…"
Leonardo's troubles became so severe that sometime around October of 1505 he stopped working on the painting altogether. Angered by this, Piero Soderini, the man who initially commissioned Leonardo, complained to the French that Leonardo was paid a substantial amount of money and had done very little work. Leonardo did eventually return, but no further work was reported as having been done. Remaining data has led modern historians to conclude that, contrary to Soderini's claims, Leonardo completed a great deal of painting.
Today none of Leonardo's original work on the Battle of Anghiari or the preliminary cartoon survives. Much of what scholars know about this project has come from Leonardo's notes and sketches as well as several copies of parts of the painting that were done before it was completely painted over in 1570 by Giorgio Vasari. Leonardo kept detailed notes about how he was going to paint each battle scene. An excerpt reads, "Make the conquered and beaten pale, their brows raised and knit, and the skin above their brows furrowed with pain…some of the victors leaving the fight and issuing from the crowd, rubbing their eyes and checks with both hands to clean them of the dirt made by their watering eyes smarting from the dust and smoke" (Field 317). The most notable copy that survives today is actually a re-work done by Rubens of an authentic copy by an unknown 16th century Italian master (Orosz). This captures the central episode of the Battle of Anghiari called the Battle of the Standard (just one scene in Leonardo's plan for the Battle of Anghiari).
Field, D.M. Leonardo Da Vinci. New Jersey: Wellfleet