Musée du Louvre, Paris (left); National Gallery, London (right)

The Louvre’s Virgin of the Rocks by Leonardo da Vinci, 1483–1490 (left); the National Gallery’s version of Leonardo’s Virgin of the Rocks, circa 1508 (right)

Exhibitions of drawings by Leonardo, almost always based on the uniquely rich collection in the Royal Library at Windsor, are relatively common. But outside the Louvre, which owns four of Leonardo’s pictures, it is rare indeed to have the opportunity of seeing more than a couple of his paintings together. The museums that possess such works are understandably reluctant to loan them, both because of their fragility and because of their fame; and apart from the Louvre, only the Hermitage in Saint Petersburg can make a plausible claim to possess more than one finished picture by him. Yet the exhibition currently at the National Gallery in London includes, according to the sponsor of the exhibition, Credit Suisse, “around half of the 15 or so paintings by Leonardo which are known to be in existence, as well as 50 of his original drawings,” including thirty-three from the Royal Collection. For most of those fortunate enough to have acquired tickets, for which demand vastly exceeds supply, this is an experience that is unlikely to be repeated.

To have brought together such a remarkable group of works is a diplomatic triumph, made possible by the generosity of the Louvre in lending the largest surviving completed work by Leonardo, The Virgin of the Rocks, which, certainly for the first time in centuries and possibly for the first time ever, is shown in the same room as another version that belongs to the National Gallery. The relationship of the two pictures has long been debated, and this exhibition provides an unprecedented opportunity to examine the problem afresh, and to see the pictures in the presence of others produced during the main period of Leonardo’s activity in Milan, between about 1482 and 1499. This was the longest time he spent in any city as an adult, but while he was there he was not working full-time as a painter. The only paintings that he is known to have certainly produced in these years are The Virgin of the Rocks, The Last Supper, now a total ruin, and the Portrait of Cecilia Gallerani—sometimes called The Lady with an Ermine—from Kraków, which is also in the present exhibition, and the decoration for a room (the Sala delle Asse) in the castle of the Sforza in Milan, which is almost entirely repainted.

As the sponsor hinted in the foreword quoted above, although Leonardo is among the most intensively studied of all European artists, the status of many of the pictures most often associated with him, and especially those supposedly painted in Milan, remains highly controversial. In particular, his relationship with several Milanese artists obviously much influenced by him, such as Boltraffio and Ambrogio de Predis, is still not fully understood. Fortunately, the selection of works in the exhibition is notably intelligent, including not just the works by Leonardo most often assigned to the Milanese period, but also paintings by other artists in the city. The usually unsympathetic display area in the basement of the Sainsbury wing has the great advantage of permitting very precise adjustment of light levels. This has made it possible to show paintings in close proximity to drawings related to them.

At the heart of the exhibition are the two versions of The Virgin of the Rocks, facing one another at either end of the main room. Although the compositions are very similar, each creates a very different impression. The figures in the Louvre version, which is universally considered the earlier of the two, are slightly smaller than those in the London picture, as well as livelier and more individualized. But the most obvious difference comes from the fact that the Paris picture is covered with a layer of dark varnish, which softens the contours and adds a sense of mystery to the landscape, whereas the version in London is brighter, with all the forms more precisely indicated and more easily visible.

This is in part the result of the very different cleaning policies of the two institutions. The varnishes available to Leonardo were naturally colored, and tended to become darker and more opaque over time. In the years after 1945 the chief restorer of the National Gallery, Helmut Ruhemann, entirely removed the varnish from a number of paintings in the collection, including The Virgin of the Rocks. This practice led to an acrimonious international controversy, with museums in Belgium and the United States siding with Ruhemann, and those in France and Italy opposing him. The critics believed that Renaissance artists took account of the characteristics of varnish when they applied it, and also argued that the removal of varnish inevitably carried the risk of eliminating at the same time the subtler layers of original finish applied by the artist.


One of those who contributed to the debate was E.H. Gombrich, who drew attention to a well-known passage of Pliny the Elder about the celebrated Greek painter Apelles, who had supposedly added a layer of dark varnish (atramentum) to pictures, in order to protect them and also to reduce the strength of the underlying colors. Gombrich suggested that Renaissance artists might have tried to do something similar. This was impossible to demonstrate, of course, since very few old paintings retain their original varnish. But some support for his position was later provided by a picture in the National Gallery by Giampetrino, who worked in Milan, but mostly after Leonardo’s extended stay in the city. This picture, which falls outside the scope of the exhibition, includes a thin overall layer of dark oil paint, which may well have been intended to have an effect similar to atramentum.

Whatever the truth of the matter, in 1961 Ruhemann published a response to Gombrich’s Art and Illusion, in which he took issue with Gombrich’s view that the term sfumato, which is particularly associated with Leonardo and refers to imperceptible changes in tone introduced by artists, also implied the blurring of outlines. Ruhemann evidently saw Gombrich’s claim as a criticism of his restoration of The Virgin of the Rocks, but Gombrich was able to justify his position by a careful and entirely convincing analysis of texts by Leonardo and others. In fact, Giampetrino’s painting includes much sfumato in the Gombrich sense.

Going around the exhibition, the differences in finish of the individual pictures, reflecting their different histories, are very evident. This applies even to the two portraits that have the best claim to be by Leonardo, that of Cecilia Gallerani and the so-called Belle Ferronière (sometimes called Portrait of a Woman; see illustration on page 12) from the Louvre, with its more opaque varnish. It is of course impossible to say what any of them looked like originally, and for this reason attempts to distinguish between the works of Leonardo and those of his contemporaries and imitators are particularly open to question.

Fortunately, the drawings do not raise comparable problems, because Leonardo, who was left-handed, consistently drew parallel strokes of hatching, to indicate shadows, sloping downward from left to right, whereas the hatching of his right-handed contemporaries slopes down from right to left. But this raises other difficulties, especially in the case of the Madonna Litta from Saint Petersburg. The head of the Virgin corresponds very closely to a beautiful drawing by Leonardo nearby, but the head of the child corresponds equally closely to a drawing by Boltraffio, which is also in the exhibition. In the catalog entry, written by a curator of the Hermitage, the picture is unreservedly attributed to Leonardo himself, but elsewhere in the catalog it is equally unreservedly, and I think correctly, claimed as a work of Boltraffio, albeit based in part on a drawing by Leonardo.

It is perhaps not surprising that in the catalog it is argued at length that the London version of The Virgin of the Rocks, which in the past has often been doubted, is “fully autograph,” like the one in the Louvre. But it is exceedingly unusual for any Renaissance artist to produce two almost identical versions of the same altarpiece, and it is certainly very surprising that Leonardo, who, by all accounts, only painted when he felt inclined to do so and was remarkably cavalier about the wishes of his patrons, should have done such a thing. I believe that the history of the commission, which is unusually well documented, cannot be reconciled with the claims made in the catalog.

The basic facts are straightforward enough. In April 1483 the Confraternity of the Immaculate Conception in the main Franciscan church in Milan signed a contract with Leonardo and with Ambrogio and his half-brother Evangelista de Predis to paint and guild an elaborate new structure behind their altar, and to supply some pictures for it by the end of the year, one showing the Virgin and Child with angels, and two others showing pairs of music-making angels. The structure included a number of carvings, the most important of which was a statue of the Virgin. There was also a representation of God the Father. The painters were to receive 800 lire, plus a sum to be assessed by one of the Franciscans and two members of the confraternity, one chosen by the confraternity and the other by the artists. There is nothing unusual about this contract, and it was recorded in 1506 that Leonardo and the de Predis brothers had received—by the end of 1490—730 lire, and that a further payment of 100 lire had been made to the brothers alone, but nothing more.*


Sometime after Evangelista’s death in late 1490 or soon after Leonardo and Ambrogio submitted a petition, probably to the Duke of Milan, in which they complained that the painting of the Madonna was worth 400 lire, and they knew of people willing to buy it at that price; but the patrons had suggested a valuation of only 100 lire. Accordingly, the painters asked that the estimators be compelled to give their views under oath, or agree to the appointment of two experts, one to be chosen by each party, or give the picture back. Evidently nothing came of this, because in 1503, when Leonardo was in Florence, Ambrogio submitted a new petition, saying that the patrons had refused to come to a new agreement or pay the price or return the picture; and once more he asked that they be compelled either to fix the price or give the picture back.

In April 1506 the patrons, after consulting experts, declared that the picture was unfinished. They said that Leonardo and Ambrogio were obliged to finish it or have it finished within two years, provided that Leonardo returned to Milan. In that case, they would pay 200 lire.

Leonardo returned to Milan shortly afterward, and in the following year the two painters were paid 100 lire. In August 1508 Leonardo informed Ambrogio that he would agree to a final settlement with the patrons on the condition that they agreed to take down the picture from the altar and deposit it in a chapel or another room of the monastery so that he could have a copy made by Ambrogio. This they would sell, sharing the proceeds. Two months later a further 100 lire was paid by the confraternity.


Musée du Louvre, Paris

Leonardo da Vinci: Portrait of a Woman (‘La Belle Ferronnière’), circa 1493–1494

The most obvious puzzle is that the London picture was in the church until the late eighteenth century, but it seems impossible that this was the earlier of the two. It has been argued therefore that the Paris picture was removed from the church, probably in the 1490s, and that the London picture was a substitute. But the documents exclude this possibility. They make it clear beyond reasonable doubt that the picture commissioned in 1483 was still in the church in 1508. Had the patrons disposed of it before that time, the painters would have had no contractual obligation to provide a new version, and no payment was made to them for one. Equally, the documents indicate that the patrons did not return the picture to Leonardo. In order to make a second version, he needed access to the original, and this was not provided before 1508. Accordingly, one picture, evidently the one in the Louvre, was supplied between 1483 and 1490, and the London version cannot have been painted before 1508.

It is difficult to accept that such an acrimonious dispute should have dragged on for a quarter of a century, if it could have been resolved by Leonardo completing a picture that, for unspecified reasons, he had delivered unfinished, and that had remained on the altar in that state. This suggests that the real problem was something different, namely that when the patrons said that the picture had not been finished, they meant that it had not been completed according to the terms of the contract. Instead of showing the Virgin and Child with angels, as was required, it showed the Virgin and Child with an angel and Saint John. But why did Leonardo not follow the contract, and why did this matter?

The patrons had a particular devotion to the Immaculate Conception, the doctrine, championed by the Franciscans, that the Virgin, the mother of God, alone of all humans had been conceived without acquiring the stain of original sin. The altar was constructed before a standard way of illustrating this doctrine had been developed, but like all early representations of the subject, it showed a statue of the Virgin standing, without the Child, and a carving of God the Father. It is often claimed that Leonardo’s painting also alludes to the doctrine in subtle ways. But this would have been redundant, and it seems unlikely.

Instead, the picture shows the Virgin as the mother of God, with her divine child worshipped by John and accompanied by an angel. In the context of the altar as a whole, the imagery would have been entirely appropriate. But the subject specified by the patrons, the Virgin and Child with angels, also had a particular significance in a Franciscan setting, because Saint Francis had founded his order and later died at the church of Santa Maria degli Angeli, just outside Assisi.

We do not know how the patrons financed their altarpiece, but it is even possible that some of the funds were given on the condition that this particular subject was represented. If so, that would explain their extreme reluctance to accept what Leonardo had provided, beautiful though it was. As Ambrogio de Predis stated in his petition of 1503, they were not willing to consider an alternative. But it is easy enough to understand why Leonardo was unwilling to finish his picture as the patrons required, because this would have involved changing the composition very radically.

Leonardo and the de Predis brothers had hoped to receive at least 400 lire, and the patrons initially offered only 100. In 1506 they raised this figure to 200, on the condition that the picture was finished. Had this happened, Leonardo would evidently have considered himself out of pocket, even though after 1506 he and Ambrogio did indeed receive 200 lire. Although the documents are silent on this point, it looks as if the patrons finally accepted the second version, for a reduced fee, and returned the original to Leonardo, who was able to recoup his full fee, including Ambrogio’s share, by selling it to a third party. How and when it entered the French royal collection has been much debated. But it may well be relevant that in 1508 Milan was under French control and that Leonardo had been given a salary by Louis XII. Although he had proposed to Ambrogio that they should sell the copy and share the proceeds, it is certain that the copy remained in the church, and it is this copy that was later acquired by the National Gallery.

The London picture does not look much like the independent work of Ambrogio known to us today, but we have no idea of his competence as a copyist. Leonardo’s own involvement, if there was any at all, is likely to have been very limited. It seems entirely out of character that he should have made a copy of one of his own works, but on occasion he certainly allowed others to do so. In comparison with the Louvre version, there is a lack of individuality and inner life in the figures, which now have a strangely gray complexion. Although much of the modeling is of great delicacy and skill, it seems obvious, now that the two pictures can be seen together, that they are not by the same hand.

The kind of differences we see between the two paintings is also evident in many of the drawings in the exhibition. Other artists in Milan, and especially Boltraffio, were able to achieve remarkable subtlety in their representation of the structure of heads and the fall of light, but only Leonardo was able to capture movement and the play of emotion, whether in his metalpoint drawings of young women or in the equally marvelous chalk studies for the apostles in The Last Supper. No artist before him, and none of his contemporaries, ever matched his complete mastery of the drawing medium. And as Gombrich long ago pointed out in a famous article, Leonardo was the first to understand how to use the sketchy, spontaneous possibilities of drawings to develop coherent and lively compositions in his paintings.

But when they lack the kind of finish that only he could provide, Leonardo’s compositions have a frozen and artificial appearance, as can be seen in all the many copies of The Last Supper, the best of which, by Giampetrino, is in the London exhibition. If one compares this with the preparatory drawings, or with the famous cartoon of The Virgin and Child with Saint Anne, also in the exhibition, one can see how much has been lost. The only paintings on display that really show the qualities that made Leonardo so outstanding are The Virgin of the Rocks and La Belle Ferronière—both from the Louvre—and the Portrait of Cecilia Gallerani, although parts of the costume of the latter have evidently suffered, giving the hand of Cecilia a rather troubling prominence.

In the past, La Belle Ferronière has occasionally been doubted, but it seems far superior to the work of any other artist represented in the show. In the catalog the proposal is made that it may show Beatrice d’Este, the wife of the ruler of Milan, Ludovico il Moro. But the resemblance to other representations of her is not close, and if she indeed had been the subject, it is surprising that the portrait did not inspire poems by courtiers, in the same way as that of Ludovico’s mistress Cecilia Gallerani. Leonardo, of course, did not only paint the high nobility. His most famous portrait, the Mona Lisa, showed the wife of a Florentine silk merchant.

Compared with these pictures, the unfinished portrait of a man holding a sheet of music, from the Pinacoteca Ambrosiana in Milan, seems static, pedantic, and slightly lacking in character. This is the only male portrait regularly attributed to Leonardo, and I share the reservations that have often been expressed about it. Much more suspect, however, is a recently cleaned painting of Christ as Salvator Mundi from a private collection. This was recorded in a print of the mid-seventeenth century, and the composition is known in other versions. But even making allowances for its extremely poor state of preservation, it is a curiously unimpressive composition and it is hard to believe that Leonardo himself was responsible for anything so dull.

These comments, of course, do not detract from my admiration for this memorable exhibition, which provides a unique occasion for thinking about one of the most problematic periods in Leonardo’s career. To see his works along with those of some of his Milanese contemporaries, and to see the paintings next to so many of his most beautiful drawings, allows the visitor to appreciate how much the other artists learned from him, and also how far, even at their best, they were from matching his achievements.