Shortly after arriving in Milan, Leonardo started to work on the equestrian monument to Francesco Sforza, but the project ground to a halt in 1489, when Pietro Alamanni wrote to Lorenzo the Magnificent on behalf of the duke of Milan to ask for the names of other metal casters. In Milan they had learned to appreciate Leonardo’s great talent but also his equally great inconclusiveness, and they had serious doubts about his ability to finish the enterprise.
The first project for the horse was extremely daring. Leonardo, as I have already said, planned to make the animal rear up with the rider in the saddle; this created the challenge of placing all the weight on the back thighs, not to mention the difficulty of making the molten metal flow from the top of the animal’s head down to its hooves, a full seven metres below. After the crisis that gave rise to Alamanni’s letter, and perhaps thanks to the advice of Florentine metal casters (possibly including Lorenzo di Credi?), Leonardo changed his initial idea and developed a more reasonable design for the equestrian monument – one in which the horse was shown trotting, a pose often seen on coins decorated with ancient monuments; but its dimensions were still colossal.
For this second design Leonardo proceeded to make a clay model that was already being admired by the Milanese in 1493, in the old court of the Sforza Castle. From this moment on, the work became the talk of all Italy. Poets and writers, trusting too much in Leonardo’s skill, started to describe the monument as one of the seven marvels of the world, celebrating it alongside Ludovico’s court and politics. Indeed, Ludovico il Moro had finally succeeded in making the other Italian courts pay attention to his duchy, no longer – or not only – for his hard-working subjects and the quality of their industrial products, but for the refinement of his courtiers. Leonardo’s fame had spread throughout the peninsula and by 1487 he was included in Giovanni Santi’s chronicle as one of the greatest artists. Leonardo was firmly convinced that the equestrian monument would become part of his legacy, and these expectations are amply borne out by his notes, where he appears to convince himself and his patron to complete the most difficult enterprise ever attempted since antiquity:
If you do not want to make it of bronze, lest it be removed, remember that all the fine objects in Rome were plundered from cities and lands vanquished by the Romans. And it made no difference if they were exceptionally heavy, like the needle [obelisk] and the two horses [Dioscuri]. And if you make it so awkward that it cannot be carried away, it will be made into walls and rubble. Do as you please, because every object will meet its end eventually. And if you say that you have no wish to make something that gives more honour to the maker than to the person who pays, remember that most things honour the name of their maker and not the payer. (Ms. Madrid I, fol. 1r)
In many ways the passage is prophetic. Leonardo understood early on that art could bring eternal fame to the artist rather than to the patron, and today we are well aware that artists have legacies that last much longer than the individuals who commissioned their works. But the passage also helps us to understand the far-reaching motivations and ambitions with which Leonardo approached this work, aiming to make his mark on history and to establish his primacy among Italian artists. It is no surprise that this ambition was not expressed in relation to painting, a field in which he had accumulated greater renown, but rather in relation to sculpting in bronze. Casting was primarily a technical skill, and in this respect Leonardo felt he could draw on the enormous pool of knowledge he had accumulated over the years through his observations of materials and machines.
In painting there were too many other players, whereas Leonardo had in mind a test that only he could pass. Casting combined all the known sciences and therefore encapsulated that ambition to exert control over the laws of nature, mechanics, pyrotechnics, not to mention every aspect of optics and mathematics, both of which were at this moment united as one in his mind, where they served the quest to create the perfect work of art. Having taken a merciless glance at his contemporaries, Leonardo was convinced not only that their attainments could be surpassed, but that this could only be achieved with the help of science and research, experimentation, and an understanding of the natural world. Leonardo’s conviction was that good art could not exist without the study of optics and mathematics, statics and mechanics, let alone the knowledge of almost all the properties of natural materials. This approach explains the important change that occurred in his mind in the early 1490s, at the very time when he met Francesco di Giorgio and resumed the project for the bronze colossus: it was then that he persuaded himself of the need to study and verify virtually the whole span of human knowledge. This was the project that – as we have already seen – prompted him to learn Latin in order to be able to read the classical sources first-hand.
After his fruitful meeting with Francesco di Giorgio, Leonardo followed his example and started to translate and interpret the classical texts directly – Vitruvius above all. During his stay in Pavia with a man who not only shared his interests but also had been able to use them successfully, becoming the mechanical, engineering and pyrotechnical expert most sought after by Italian princes, Leonardo felt compelled to draw up an encyclopaedic programme of study and work.
Get the master of abacus to show you how to square a triangle. Get Messer Fazio to show you [the book] on proportion [Fazio Cardano, a professor at Pavia and printer of John Peckham’s Perspectiva Communis in 1482]. Ask the friar at Brera to show you De ponderibus … Ask Maestro Antonio how bombards are placed on bastions by day or at night. Ask Benedetto Portinari how to run on the ice in Flanders. Regarding the proportions of Al-kindi, with notes by Marliano, Messer Fazio has a copy. The measurement of the sun, promised me by Maestro Giovanni, the Frenchman…. Groups by Bramante, Metaura by Aristotle, in Italian. Try to get Vitolone [Witelo, the thirteenthcentury Polish optical theorist], which is in the library at Pavia and treats of mathematics. (Codex Atlanticus, fol. 611a)
Seeking out men and books, experimenting with flight and the laws of fluids, rationalizing the layout of canals in the countryside of Lombardy, designing the tiburio for the cathedral in Milan and the cathedral in Pavia, casting the bronze horse and planning festivities, dissecting corpses to discover the laws of human motion in order to draw it more accurately: the artist was overwhelmed by a mania for omnipotence in the febrile pursuit of everything that constituted knowledge. At long last, helped by the advice of Francesco di Giorgio – who had worked in Siena with Paolo Biringuccio, the greatest European expert in metallurgy (his son, benefiting from his teaching, would write a famous treatise Della pirotecnica) – Leonardo made arrangements for the moment of casting.
Leonardo drew the casework in painstaking detail. He decided to cast the parts of the horse on the horizontal and then to weld them together, and he asked a number of friends who were knowledgeable in metallurgy and chemistry to join him; these were old acquaintances from Florence who would help him in the task. Between 1492 and 1493 he hosted in his house two expert foundrymen, a certain Mastro Giulio, who was German, and a certain Tommaso (Zoroastro): ‘February 1492, On Thursday 27 September Maestro Tommaso came back and he worked for himself until the last day of February. On 18 March 1493 Iulio the German came to live with me until 6 October’ (Codex Forster III, fol. 88v). Five collaborators lived with Leonardo in his house in around 1492, and in 1494 they were joined by a Spaniard: a certain Ferrando, a painter. Running a household of artists is not simple, above all when one of them was a light-fingered youth like Salai and another was a blacksmith who dabbled in astronomy and magic like Tommaso Masini, who went by the name of Zoroastro and is remembered for his pranks rather than for his works of art. The household was looked after by just one servant, poor Caterina, whom some have identified as Leonardo’s mother, who joined him in Milan in her old age so that she could spend her last days with him (but this hypothesis is completely unfounded).
Even if the project for the horse and its casting served as a focus of activity for Leonardo and his workshop, the artist seems not to have turned down other commissions proposed by Ludovico il Moro. Between 1487 and 1490 he was busy designing a model for the lantern [tiburio] of the Duomo of Milan, but his design was rejected in favour of one proposed by the more concrete and practical Francesco di Giorgio Martini. Once again, despite Leonardo’s spark of genius and his wide-ranging expertise, when it came to giving tangible form to an architectural project of public significance, his plans were disregarded. The same happened with the commission to cast the bronze doors for the cathedral of Piacenza, a project that Leonardo tried to obtain using a stratagem that was, by all accounts, unusual. The Codex Atlanticus contains the draft of a letter that Leonardo planned to ask a trusted friend to write; the letter was designed to advise the committee responsible for the cathedral [the fabbricieri] to give him the job. Leaving aside any pretence at modesty, this imaginary friend, who was none other than Leonardo himself, in his habitual split personality, recommended the artist as the best possible candidate:
There is no man capable, believe me, except Leonardo the Florentine, who is making Duke Francesco’s horse in bronze, although this need not be taken into account because it is work that will last all his life; and being so great a work, I doubt whether he will ever finish it. (Codex Atlanticus, fol. 887r–v)
The passage is certainly unusual and indeed it could perhaps be read as simple fantasy, given concrete form on paper by a mind that was overly engaged in swift repartee with its alter ego. Whereas on the one hand this draft autograph letter reveals Leonardo’s praise for himself as the best foundryman in the world, on the other his own mind tells him that perhaps he will not be able to complete the task.
As if the treatises started during this period did not give him enough to do, Leonardo still had to resolve the question of The Virgin of the Rocks with the Franciscan friars. His demand for a higher price reveals how profoundly his attitude to the production of paintings had changed. In the contract of 1483 the monks intended to commission a classic fifteenth-century ancona, an altarpiece structure with a monumental frame, carved and gilded, and in the centre the actual painting that, according to medieval custom, was valued more for its gold and lapis lazuli than for its pictorial quality, which for the patrons had no intrinsic value at all. But Leonardo knew that, precisely in the painting of the Madonna, he had produced an artistic miracle, which had nothing whatsoever to do with contemporary artisanal production: there was virtually no gold or lapis lazuli (just a small amount on Mary’s cloak), but here was something that contemporaries were not yet able to evaluate, namely artistic talent, which, Leonardo realized, could be turned into economic value.
Private collectors were also aware of that value, and in turn they had started to use works of art as political currency. In particular, an anonymous art collector – whom Leonardo refers to in his complaint – was offering a much higher price for the painting. This explains why Leonardo approached Il Moro with a complaint that stressed how the original price, agreed at 200 ducats, had barely covered the cost of the wooden ancona decorated by De Predis and that the painting alone was worth the additional price of 100 ducats that had already been requested.
Notwithstanding that the said two works are worth ccc [300] ducats, as recorded on an inventory by the said suppliants [Leonardo and De Predis] given to the said scolari [members of the confraternity of the Immaculate Conception, in the church of San Francesco Grande], and the said suppliants have asked the said commissioners to make the said valuation with its sacrament, but yet they do not wish to make one nisi de equitate [unless fairly], wishing to value the said Madonna painted in oil by the said Florentine only at XXV ducats, instead of valuing it at 100 ducats, as stated on an inventory held by the said suppliants, and they have been offered the sum of 100 ducats by persons wishing to buy the said Madonna; hence they are obliged to appeal to Your Lordship … quod cechus non iudicat de colore [because the blind cannnot judge colour]…. Given that the relief work on the said ancona alone amounts to the said 800 imperial lire that the suppliants have been paid, this sum has been spent on costs.19
This financial tussle marks the emergence, for the first time, of an understanding of the value of art. In the end the painters pulled it off because the friars of San Francesco had to settle for another painting that, as was said earlier, would only be finished ten years later. Meanwhile, this plea can perhaps claim the status of being the first modern valuation of a work of art, a valuation that did not use as benchmark the amount of gold and lapis lazuli the painting contained, but rather the artist’s talent.
From then on the development of the art market in Italy was open to all possibilities, and Leonardo was paid 100 ducats by the new and anonymous admirer; this sum allowed him to continue working on the project of casting the colossal horse (three times larger than life) that all had admired in the old courtyard. The entire Milan was waiting to see the completion of the miraculous casting, for which, as Leonardo himself would write to Ludovico, he had paid six workers for three years, receiving only 50 ducats in exchange. In 1494 the casting was ready to start: Leonardo’s plans have survived and some seventy tons of bronze had been collected. These would have to be poured through the vents and turned into the smoothly rounded features that the artist had compiled from the best horses in the ducal stables, in drawings listed one by one, as if they were human models.
But on this occasion Leonardo’s ambition came into conflict with the even greater and more reckless ambition of his great protector, Ludovico, who had isolated his nephew Gian Galeazzo, the legitimate heir to the duchy, in a sort of childish limbo in Pavia Castle. But the duke had misjudged the determination of his niece, Isabella of Aragon, who may have inherited even from him her decisive and wilful temperament. Isabella had no desire to give in to her uncle’s arrogant demands; and she urged her grandfather, King Ferdinand of Naples, to entrust the government of the duchy to her husband, Gian Galezzo. In order to counter the threat posed by Ferdinand of Aragon, Ludovico allied himself with the French and supported Charles VIII when the latter invaded Italy with the aim of conquering the kingdom of Naples. This was the first in a series of errors made by an overly cynical and overly ambitious Italian prince, which were to cause atrocities after atrocities in the peninsula, culminating with the Sack of Rome of 1527. But in the early months of this alliance Ludovico appeared to have resolved his problem. Indeed, Charles VIII’s arrival at Asti on 11 September 1494 bolstered Ludovico’s confidence sufficiently to convince him to stage the accidental and providential death of poor Gian Galeazzo – who, with admirable timing, died in inexplicable circumstances on 22 October.
Ludovico finally became the legitimate duke of Milan; and, in order to extend his alliances, he offered the young Habsburg emperor, Maximilian of Austria, a huge sum of money together with his own niece, Bianca Maria Sforza, sister of the unfortunate Gian Galeazzo. Everything went according to plan, at least in appearance, until Charles VIII’s triumphant conquest of Naples, which prompted fears that Milan might now be subject to the threat of French annexation. At this point Ludovico reversed two major alliances, first by entering a pact with Venice, Milan’s historical rival in northern Italy, and, second, by supporting the revolt of Pisa against Florence, the city that had been one of the closest allies of the dukes of Milan for the past half-century. Since he had not hesitated before spilling the blood of his own relatives, Duke Ludovico certainly did not think twice before betraying the friendship of the Florentines. Relying on his warlike past, he prepared to resist the French, whom he defeated at Fornovo near Parma with the help of Sanseverino, his companion in the festivities prepared by Leonardo.
Within the space of a few months the sparkling masques of the ‘savages’ in paradise and the splendid jousts were transformed into the more sinister gleam of battle armour, and the importance of the equestrian monument to the father of the fatherland [Padre della Patria] was superseded by the drumbeat of war. The metal amassed for its casting was used for the cannons that would fire at Fornovo. This change of mind is documented with customary sobriety by a diplomatic dispatch:
On 17 November 1494 the Duke of Ferrara, having been 17 days in Milan … received the gift of 100 miera [158,700 pounds] of metal from the duke, who had bought it to make the horse in memory of Duke Francesco; the said copper was transported to Pavia, then along the Po to Ferrara, and also Maestro Zanin went with him, to manufacture artillery.20
Ludovico il Moro’s first political act as the legitimate duke of Milan was to turn the metal destined for Leonardo’s horse into weapons. The artist’s dreams of glory, which poets had been too hasty to praise, faded as the rounds of artillery echoed over the battlefield. In 1495 the clay model was still there, in the old courtyard, as a testament to the artist’s creativity, but even that would not survive the fury of a new war. Defeated at Fornovo, the French withdrew north of the Alps, but after Charles VIII’s death Louis XII became king of France and, as nephew of Valentina Visconti, he had legitimate grounds to aspire to the duchy of Milan. Ludovico was in despair. He abandoned Pisa and the alliance with the Venetians, who as a result drew closer to Louis XII, in a move to undermine the unreliable duke. Ludovico’s fate was sealed. The French laid siege to the duchy and occupied its capital, Milan, in September 1499.
The city was deprived of its political autonomy for ever, and Leonardo lost his great protector. It was the end of an epoch and once again his ambitions had been thwarted. It would be a work in which he never believed that would bring him eternal glory in Milan and the rest of Italy, a painting he had undervalued to the extent that, in a letter to Il Moro in 1497, he said he was obliged to paint it in order to earn a living and repay the costs incurred for the failed project of the bronze horse, almost as if to equate painting to forced labour.