National Gallery Technical Bulletin Volume 19, 1998

Three Paintings by Caravaggio
Larry Keith

The study of Italian Baroque painting technique has been relatively neglected when compared to the understanding gained both of earlier Renaissance artistic production and of seventeenth-century Northern European practice. However, a most notable exception to this tendency is the study of the work of Caravaggio, whose painting technique has been the subject of intense scrutiny in numerous recent publications and exhibitions (note 1). This scrutiny has been particularly fruitful, for his work often demonstrates characteristic technical idiosyncrasies that are important in arriving at clearer solutions for long-standing attributional or chronological problems, as well as suggesting a subtly different role for the study of painting technique itself within the context of the Italian Seicento.

Caravaggio in the National Gallery

The three Caravaggio paintings in the National Gallery span the greater part of his working life, and while they do not contain every technical feature found in his work, seen as a whole they provide an excellent overview of the evolution of his painting practice.

The National Gallery's earliest Caravaggio is the ‘Boy bitten by a Lizard’, generally agreed to have been painted in the second half of the 1590s, perhaps during his residence at Cardinal Del Monte's palazzo, a date largely based on its close stylistic similarities with other known and dated works from the Del Monte period. Before examining it in detail, it is worth briefly considering Caravaggio's earlier career. He arrived in Rome from his native Lombardy in about 1592, and began working in the studio of one of Rome's more successful painters, the Cavaliere d'Arpino. He was probably employed there as a sort of specialist painter of still-life and genre subjects; both the Galleria Borghese ‘Boy with Fruit Basket’ and the ‘Bacchus’ were recorded as being in the Cavaliere's possession in 1607 (note 2).

After leaving Arpino's workshop, Caravaggio's first ambitious early picture to find an important buyer was the ‘Cardsharps’ (now in the Kimbell Art Museum), purchased by Cardinal Francesco Maria del Monte. Caravaggio was resident in his house, the Palazzo Madama, from 1595 to 1600. Del Monte was crucial to Caravaggio's development. Through him he became acquainted with many influential collectors – for example Vincenzo Giustiniani, who owned thirteen Caravaggios at his death in 1638, and Cardinal Federico Borromeo, who came to own the Ambrosiana ‘Still Life’, and Ciriaco Mattei, the patron of both the London ‘Supper at Emmaus’ and the Dublin ‘Taking of Christ’. Among Del Monte's other Caravaggio paintings were the Rome ‘Fortune Teller’ and the New York ‘Musicians’. Del Monte was also important in helping Caravaggio to secure his first major public commission in 1599–1600, the ‘Calling and Martyrdom of Saint Matthew’ for the church of San Luigi dei Francesi (note 3).

This group of work, with its strong emphasis on still life and genre presented in a relatively naturalistic way, was seen by contemporaries as distinctly North Italian in character, even deliberately Venetianising. The critic and biographer Gian Pietro Bellori, writing later in the seventeenth century, described the ‘Card-sharps’ as being 'painted in that straightforward manner of Giorgione, with tempered shadows' (note 4). Federico Zuccari, one of Rome's most successful artists, is said to have responded to the Saint Matthew canvases by saying ' I see nothing here beyond Giorgione's conception of painting' (note 5). The seventeenth-century association of Caravaggio and the Venetian tradition was largely based on relative naturalism and extensive use of dark shadows, and would be seen today as a rather crude characterisation of sixteenth-century Venetian painting. Beyond the fact that Caravaggio was if anything Lombard in his formative influences, this contemporary stereotyping of him as a northern artist nonetheless describes something fundamental about Caravaggio's style, as well as the actual process and technique of his painting. While his technique evolved at least as much as his style, his North Italian origins are important to an understanding of both. Caravaggio's early teacher in Milan, Simone Peterzano, was a pupil of Titian, and the existence of grey grounds demonstrated in some early works of Caravaggio such as the Kimbell ‘Cardsharps’ or the Capitoline ‘Fortune Teller (note 6)’ has direct precedent in the Lombard painting of Moretto and Moroni. Even if darker grounds had become commonplace throughout Italy by 1600, perhaps the longer tradition of their use in northern Italy allowed Caravaggio to expand the potentialities of the technique more thoroughly, both in terms of economy of effort and toward specific painterly effects.

‘Boy bitten by a Lizard’

The ‘Boy bitten by a Lizard’ was painted on a single piece of plain-weave linen canvas, built up over a red-brown ground made up predominantly of calcite, earth pigments and a little lead white. A ground of this constitution is naturally translucent as well as dark in colour (note 7). Such a ground is not unusual in seventeenth-century Italian painting, and it is worth describing in some detail the way in which its warm brown colour was exploited in Caravaggio's work in the subsequent application of paint. The ground is clearly visible in several areas, and was of great importance in providing a ready made middle tone in much of the painting of flesh and hair. A detailed view of the shoulder, chin and neck shows this more clearly; the brown tone of the ground, visible in the unpainted area between the shoulder and background paint, is left exposed or lightly veiled with darker paint to provide much of the half-shadow in the modelling of the inner shoulder and collarbone, chin and shadowed cheek. This technique was by no means restricted to Caravaggio, yet was exploited with great economy and sophistication by him; it was a distinctive enough feature of his work for Bellori to comment upon: 'he left the imprimatura of the canvas for the middle tones' (‘lasciò in mezze tinte I'imprima-tura della tela’) (note 8). The opacity of lighter colours is increased by the darker underlayer, while thinner and more transparent darker paint is given increased depth and luminosity by the relative lightness of the same ground, allowing a broad range of tenebristic effects to be achieved in a direct and simple system. However, oil paint becomes more transparent as its refractive index rises with age, which means that in many seventeenth-century pictures the tonality of the ground now has a slightly exaggerated effect. In the ‘Boy bitten by a Lizard’, for example, while the ground was clearly intended to have a major function in the modelling of the hair and robe, both the change in refractive index and wearing of upper paint layers have now given the ground colour greater prominence in these areas.

The manipulation of transparencies and opacities inherent in different paints was an important feature of Caravaggio's practice, as medium analysis carried out on samples taken from the ‘Boy bitten by a Lizard’ has shown. Although the picture seems to have been painted for the most part in walnut oil, a sample taken from a white highlight of the shirt sleeve near the elbow shows this passage to have been painted in a mixture of oil and egg tempera, a medium which produced a cooler and more opaque white than would have been obtainable with oil alone (note 9). The result is an even broader range of tonal modelling that increased the tenebristic effect so important to the illusion of the painted figure. A detail of the contour between the shoulder and background shows that the background paint was brought up to the already painted shoulder, and was in effect one of the last parts to be painted; this is confirmed in the X-ray image, where the grey paint with its dense lead-white component registers as light and can be seen to have been brought around the contours of the entire figure, in the same way that the paint of the tablecloth was added around the painted still-life elements.

Another version of the ‘Boy bitten by a Lizard’, now in the Fondazione Longhi in Florence, raises the question of Caravaggio's interesting practice of producing a replica of a successful composition. The Longhi picture is now generally accepted as an autograph work (note 10), but the manner in which it is painted, with its thicker application of paint across the tonal range of the flesh paint as visible in the X-radiograph, for example, points to it being painted earlier than the London picture. The relative opacity even of the shadowed side of the face, shown by its relative lightness from the lead white in the flesh mixture, is readily visible in a comparison with the X-ray of the London picture. Interestingly, however, a misinterpretation of the X-ray evidence has caused some confusion in establishing the sequence of the execution of the two works. The background paint around the upraised hand of the London picture, while appearing uniformly opaque to the naked eye, was actually applied in brushstrokes of rather variable thickness. The X-radiograph shows this variation in thickness quite clearly, and has led to it being erroneously interpreted as a significant pentimento in the hand. Since this hand shows no sign of any positional change in the Longhi version, and is placed identically to what was wrongly believed to be the finalised position in the London picture, the implication which has been drawn was that the London version was painted first. This proposed sequence, based on a misunderstanding of the X-ray evidence, contradicts all the other technical and stylistic evidence in the two works, and it shows clearly the dangers of relying too heavily on X-radiographs alone. Denis Mahon has pointed out that the Longhi picture is more reasonably dated soon after Caravaggio's arrival in Rome, around 1593–4, and proposed a date of about 1597–8 for the London version (note 11). The impression of a more systematised painting method in the National Gallery picture, with its more economical use of the ground colour in the modelling, is consistent with a later date both within the general terms of Caravaggio's technical evolution and in particular as a second version of a repeated composition.

While this example of the production of an autograph replica is perhaps unique in Caravaggio's career, there are other examples of his reworking compositions. It has recently been conclusively demonstrated by Keith Christiansen that Caravaggio's first version of ‘The Lute Flayer’, now in the Hermitage, was used as the basis for the picture now in the Metropolitan Museum, presumably to fulfil the request of Cardinal Del Monte to have his own painting of the image he would have seen in the Giustiniani collection (note 12). The X-ray photograph of the New York picture shows that Caravaggio directly transferred the image of the first version onto his canvas, and even began to paint elements from it that are not now visible, such as the still life of fruit in the lower left corner, before making major modifications to the foreground, the angle and type of lute, and the shoulders of the figure. The two pictures also share a general similarity in their stylistic and technical development to that which exists in the two versions of the ‘Boy bitten by a Lizard’; both second versions are painted in the sparer and almost abstracted, harsher style characteristic of Caravaggio's mature Roman period.

Also noteworthy in these paintings, at least in the first versions, is the apparent use of live models, a practice which was commented upon by Caravaggio's contemporaries as a particularly innovative feature of his working method, and is generally agreed to have been widely used in the early, single-figure works of this period (note 13). Indeed, one of the more revolutionary aspects of these images is the combination of composed, classical subjects with the impact of strongly characterised, naturalistic models. However, the limitations of working from live models in larger compositions had been described by Giulio Mancini, who wrote that, 'while painting from a model can produce good results with pictures of single figures, it does not work as well when painting a large narrative composition, it being impossible to put a multitude of men in a room to represent a narrative and have one who laughs or cries or feigns walking while he stands still to be copied (note 14). It has been shown that the Metropolitan Museum's ‘Musicians’ cannot have been produced by posing four figures together, as the relative position of the central lute player to the singer would have been physically impossible; rather it was composed as 'a collage of individually posed models' (note 15). This in turn allowed the use of a single model for more than one figure, as has been suggested with the Cupid and singer in the New York picture.

‘The Supper at Emmaus’

Painted for Ciriaco Mattei in 1601 (note 16), the ‘Supper at Emmaus’ is not a great deal later than the ‘Boy bitten by a Lizard’, but it nonetheless displays a significant step forward from the earlier more self-conscious, posed-looking single-figure images to an ambitious multi-figured composition. It is a further evolution in solving the tensions arising from the combination of the realism of painting from live models and the artifice of a carefully planned composition, which in turn required an expansion of Caravaggio's working practice to accommodate the more elaborate groupings.

The picture, also painted on plain-weave linen canvas (with a single horizontal seam), was built up over a ground very similar to that of the ‘Boy bitten by a Lizard’: a translucent mixture of calcite and earth pigments with some lead white (note 17). In this picture, one of Caravaggio's most highly finished works, the ground is more extensively covered by his subsequent application of paint than it is in the ‘Boy bitten by a Lizard’, particularly in the flesh painting, although the priming is visible as a middle tone in much of the hair, around the ear of the figure on the right, and in the contour between the seated figure's shoulder and the background paint. It also is visible in several details of the still life, whether left exposed to provide the shaded area of the goblet, for example, or deliberately left uncovered to provide areas of the pattern of the table carpet. Close examination of the base of the goblet not only shows the use of the exposed ground, but also reveals traces of brushed drawing in dark brown paint, slightly above the finalised contour of the base of the glass, which was presumably used to lay out the design of the elaborate still-life arrangement (note 18). The traces of underdrawing for the still life, while they would not be remarkable in many other artists' work, take on a special significance with Caravaggio, by whom no firmly attributable drawing survives. Much has been made of the tradition of Caravaggio as an improvisational artist working largely ‘alla prima’ from life instead of employing the traditional stepwise evolution through various preparatory drawing stages to a final composition. Yet, care must be taken to distinguish between Caravaggio's attitude toward the established role of ‘disegno’ and his evident abilities as a draughtsman, even if most of that evidence now lies beneath subsequent applications of paint. The compositional complexity of the picture, the evidence of local brushed underdrawing in the still life, and the economical application of paint suggest a fairly elaborate local preparation (at least on the canvas) and therefore a more flexible attitude toward the use of drawing skills than might be expected. The composition was clearly carefully laid out prior to painting; there is only one pentimento of any consequence, and in general the painted forms do not overlap one another and were therefore precisely arranged on the canvas in an early stage of the painting process. Numerous local contours between compositional elements do not overlap in paint, and this can be seen in the area around the servant's ear, where the ground remains uncovered between the hairline and collar.

While the still life may have had a fairly highly finished brushed drawing, it seems that Caravaggio pragmatically evolved different techniques for positioning the figures. The intersection of the right-hand figure's sash and the tablecloth shows two rapidly executed, highly impastoed diagonal brushstrokes that summarily indicate the position of the sash. This type of summary indication, or ‘abbozzo’ – used as a rough guide to the placing of forms – was often employed by Caravaggio as well as lines incised freehand into the still malleable priming in many mature works. Although none is readily apparent in the ‘Supper at Emmaus’, these incisions are a distinctive characteristic of his practice (note 19). Scratched freehand, they are little more than schematic indications of the position of key elements, and the finished paintings frequently show considerable changes from the initial incisions. They seem to have functioned, together with the painted ‘abbozzo’ indications, to fix the location of the figures within the composition, and also to help models to resume their established poses in subsequent sittings – an important consideration given the relative emphasis on painting from the model and not from highly worked preparatory drawings. Indeed, as has been pointed out by Christiansen, many of the pictures of the period between 1595 and 1605 have the character of ‘tableau vivant’ reconstructions of striking immediacy, and the incisions that allowed the repositioning of models still permitted the realistic impact of painting the figure from life within highly considered, complex compositions (note 20).

The ‘Supper at Emmaus’ does not clearly show a general system of incised lines, even though it is obviously a very carefully staged picture. This may well be due to the lines having been faint to begin with, because of a relatively dried ground layer at the time of incision; there is certainly considerable variation in terms of depth and fluidity in recorded incision marks on a number of Caravaggio's works. Furthermore, the ‘Supper at Emmaus’ is one of Caravaggio's more highly finished paintings, and such lines as may have been incised might simply have been obscured with subsequent paint (note 21). The high degree of planning and preparatory work everywhere else on the canvas is if anything emphasised by the one significant change undertaken during the course of painting – a readjustment of the carpet and of the breeches of the figure on the right. A cross-section taken from the edge of the area of the breeches shows a brown-green layer containing green earth and malachite, with what presumably was a highlight of lead-tin yellow added above, indicating that the breeches were first a similar green to the jacket of the figure at left, which was painted with the same combination of pigments. These breeches were later changed to black, and the sample shows a layer of pure unmixed black pigment above the green paint. Another cross-section from the table carpet just to the left of the breeches is also significant: the reddish-brown hue in most of the carpet pattern across the bottom is given by more or less exposed ground, but in this section it shows as a distinct paint layer of red ochre and black applied over the same complex build-up that can be seen in the breeches. This indicates that the original composition had the leg placed in front of the table carpet, but as the painting progressed the leg was subsequently placed behind it. This simple change both enhances the ‘repoussoir’ effect of the seated figure at left, whose sudden backward-moving reaction threatens the picture plane, and also increases the illusion of the extraordinary forward projection of the outstretched arm at right. But elsewhere the painting proceeded according to the plan of the preliminary work; painted forms do not overlap, so, for example, the white tablecloth is painted around the still-life elements, except for the final feathering-out of shadow glazes onto the white paint. The painting is also characterised by its high degree of finish and surface effect, perhaps relating to the circumstances of its commission. This impression of high finish is reinforced by the results obtained by medium analysis; while the great majority of the picture was painted in walnut oil, Caravaggio has used egg tempera mixed with a little oil to paint the raised embroidery threads on the white tablecloth, giving a denser, more readily impastoed, whiter white (note 22).

‘Salome receiving the Head of John the Baptist’

The surface effect and finish, while carefully considered, are quite different in a later work like the ‘Salome receiving the Head of John the Baptist’, and are characteristic of Caravaggio's broader, later painting style. Probably dating from 1609, the picture was also painted in walnut oil on plain-weave canvas over a somewhat darker ground of mixed earths and calcium carbonate, with a little lead white and carbon black. The canvas edges were crudely serrated at some time after the beginning of the nineteenth century, and these serrations have been filled and extended to a width of about one centimetre; there is no reason to suppose that any significant loss to the composition has occurred. There are very few incisions visible except for one across the Baptist's mouth and another around the old woman's ear, although others may have been concealed by paint. More readily visible, however, is the vigorous ‘abbozzo’ underpainting detectable in the drapery and flesh. The diagonal white brushstroke running up through the deep shadow above the executioner's belt contradicts the curving folds painted above it (Plate 12); now partially revealed through abrasion of the darker covering paint, it is clearly from the preliminary laying-in stage. Similarly, the light stroke delineating the upper contour of the executioner's draped shoulder was probably also first put down in the initial sketching-in. Although strengthened, particularly in the highlight next to the neck, this stroke did not require major adjustment and was incorporated into the finished painting. For laying-in and positioning the main features of the flesh paint a pinkish-red underpaint was used. Caravaggio developed the practice of roughly laying-in the ears to indicate position of heads (note 23); for example, the ear of the old woman, both incised and sketched-in, was later completely covered by her headdress, and is now visible only through the combination of the increased transparency of the paint films and the wearing of the upper layers. The ear of the Baptist was similarly laid in, then covered by hair, and then more finely indicated with the small highlighting stroke most prominently visible at present; the rest of the ear was not originally intended to be seen. Additionally, pink brushstrokes that summarily indicated the pose of the old woman's hands, which were also covered by the later brown paint, are also now just visible through a combination of wearing and increased transparency of the upper layers.

The general impression is of a broad, possibly hasty, application of paint in a loose and free manner; some scholars have even suggested that the painting remained unfinished, on the basis of what appears to be the great prominence of the brown ground. Close inspection of the executioner's face shows this broad handling very clearly; Caravaggio has departed from the finely modelled tonal gradations of his earlier work. Yet this later style is no less considered, and the impression of haste is deliberately created by a highly controlled application of paint. What appears to be exposed ground, for example, is often priming-coloured brown paint applied near the end of the painting process. The brown colour between the executioner's fingers is paint applied last, not the ground showing through, and similar late application of brown paint can be seen in the executioner's eye sockets, neck, chest and right arm. Thus, while the ‘Salome’ demonstrates considerable economy of effort, it is the look of a loose execution rather than the performance of a speedy technique that seems to have been Caravaggio's prime concern. The highlights on Salome's sleeve, for example, have all the character of the preliminary ‘abbozzo’ indications, yet were applied last over the painted drapery. The late application of the brown ground-coloured paint in the flesh painting is perhaps more explicable as a deliberate suppression of the chromatic range, thus heightening the dramatic lighting.

The reduced palette, chiaroscuro, and ‘abbozzo’-like handling are strongly characteristic of the appearance of the late works, and these technical and stylistic features are of prime importance in the establishment of the ‘Salome's’ date. Although the same combination of careful compositional planning and broad technique is evident on other firmly datable late works such as the ‘Beheading of Saint John the Baptist’ of 1608 from Malta, there has been much discussion about the date of the National Gallery ‘Salome’. This is largely because of the uncertain relationship between the London picture and another, autograph version of the same subject, and also because of an ambiguous documentary record. Like the National Gallery ‘Salome’, the Malta ‘Saint John’ has almost no overlapping of painted forms; its composition is carefully planned, and while there are no obvious incisions, traces of brushed drawing can be seen in areas left relatively exposed by design or time (note 24). In spite of the considerable difference in scale, both pictures achieve their desired effects through surprisingly considered means, even if the Malta picture has a less deliberately cultivated ‘non finito’ appearance. It seems therefore that the question of the degree of finish in Caravaggio's œuvre cannot be described as a simple evolution from tight to loose handling, but instead shows a more fluid development, taking into account local variations in handling based on factors like the format, intended siting, or function of each commission (note 25). Nonetheless, the general progression is toward broader handling and a greater use of the ground or ground colour to increase the drama of the tenebristic effects.

The question of the broad finish loosely associated with the 'late style' is a significant factor in understanding the relationship between the London ‘Salome’ and the version of the same subject which is now in the Patrimonio Nacional, Madrid (Plate 16) (note 26). Bellori describes a picture painted during Caravaggio's second stay in Naples in 1609–10, after his escape from Malta and subsequent stay in Sicily, as a 'half-length of Herodias [Salome] with the head of the Baptist on a platter'. He implies that the picture was intended as a sort of peace offering toward Alof de Wignacourt, Grand Master of the Order of St John, the Knights of Malta, to ease the artist's strained relations with the Order from which he had just been expelled (note 27).

While there are no firm documentary links between the picture described by Bellori and the National Gallery ‘Salome’, circumstantial evidence based on comparison of the technique and handling of the London and Madrid pictures certainly suggests that the London canvas is the later in date, and therefore the more likely of the two to match Bellori's account. The Madrid picture is painted with the thicker application, more careful modelling, and richer palette normally associated with Caravaggio's earlier work, and has very little of the severely limited palette (note 28), broad handling and economy of effect seen in the London version. This general impression is reinforced by specific comparison of the handling of the heads of Salome and the Baptist, and of the headdresses of the attendant women. In addition, the ‘abbozzo-like’ finishing strokes and the broken modelling used for the hands of the executioner and the old woman in the London picture are wholly absent from the Madrid version. Therefore, if the Bellori reference does indeed refer to one of the two pictures, the weight of the technical evidence firmly favours the London version.

Conclusion

With Caravaggio, the study of technique requires more than a straightforward analysis of the materials he used and their application, for in this respect much of his technique was quite conventional. Whereas study of technique in the Renaissance, broadly speaking, shows that the more complex and transitional painting materials and techniques are often more locally characterisable, in Spanish and Italian seventeenth-century painting, where a relatively simple range of materials is found, technical distinctions are generally based on handling. In Caravaggio's work, however, any discussion of technique must include an expanded notion of his working processes – in particular his use of models and the role and nature of preparatory work. As we have seen, some of Caravaggio's technical idiosyncrasies are also important for attribution and dating; as far as is known, no other artist seems to have used incised lines in quite the same way, for example. The New York ‘Lute Player’ has been proved to be an autograph work in spite of a received critical tradition against an attribution to Caravaggio (note 29); in this instance the documentary and technical arguments in its favour have refined our understanding of the artist's stylistic evolution. Furthermore, its now established technical and stylistic relationship to the earlier Hermitage version of the same subject has become of prime importance in explaining what appears to be a parallel relationship between the two versions of the ‘Boy bitten by a Lizard’. The differences in handling and technique in the two ‘Salomes’ also provide the clearest available explanation of their relative chronology.

An understanding of Caravaggio's technique is also vital for an assessment of one of the fundamental critical issues in his art – the nature and extent of its naturalism. Quite apart from the high incidence of still-life elements, there is clear evidence of his use of models to suggest the importance of painting objects and people from the life. Many of his more idiosyncratic technical practices seem to be based on a desire to incorporate a more realistic element into the traditional practice of contemporary history painting, most obviously in combination of ‘abbozzo’ laying-in on a dark ground, together with incised lines, to facilitate the greater role of live models. It is interesting to note the pragmatic nature of his technical innovation; it appears less evident in areas where established traditional practice may have been perfectly adequate for Caravaggio's purposes, as we have seen in the evidence suggesting a more conventional use of drawn preparation for the sort of complex inanimate still-life elements depicted in the London ‘Supper at Emmaus’. While this comparatively realistic aspect of Caravaggio's painting has been widely appreciated in terms of his radical imagery and iconographical innovation, the link between the new stylistic attitude and its parallel technical innovations is often neglected. One must be careful not to overstate the case – a naturalistic element in the creative process is not the same thing as a realistic intent, and the numerous expressive anatomical distortions and spatial incongruities present in many works contradict any suggestion of a simple literal-minded realism. While working from nature was a major element of Caravaggio's highly innovative imagery, and a spur to much of his technical innovation, it was not its final object, but a means to a different end – his highly distinctive amalgam of realism and artifice.

Acknowledgements

I would like to thank Dr Gabriele Finaldi, Curator of Spanish and later Italian Painting at the National Gallery, for his many helpful comments and discussions on the subject. I would also like to thank Dr Juan Martinez-Cuesta, Curator of Paintings at the Patrimonio Nacional, Madrid, for allowing me to examine the ‘Salome’ and the staff at the Opificio delle Pietre Dure, Florence, for allowing me to view the Malta ‘Beheading of Saint John the Baptist’ during its recent restoration there.

Notes and references

1. Recent examples of exhibitions with detailed technical catalogues include Giampaolo Correale (ed.), ‘Identifi-cazione di un Caravaggio: Nuove tecnologie per una rilettura del San Giovanni Battista', 1990; Keith Christiansen, ‘A Caravaggio Rediscovered: The Lute Player’, The Metropolitan Museum of Art, New York 1990; and Mina Gregori, ‘Caravaggio: Come nascono i capolavori’, Milan 1991.
2. For a summary of Caravaggio's early Roman period see Christiansen 1990, cited in note 1, pp. 9–11.
3. See Christiansen 1990, cited in note 1.
4. '... in quella schieta maniera di Giorgione, con oscuri temperati', Giovanni Pietro Bellori, ‘Le vite de' pittori, scultori, et architetti moderni’, Rome 1672, p. 204.
5. To no ci vedo altro, che il pensiero di Giorgione', recounted in Baglione's ‘Le vite de' pittori et architetti’, Rome 1642, p. 137. For further contemporary critical opinion, see Janis C. Bell, 'Some Seventeenth-Century Appraisals of Caravaggio's Colouring', ‘Artibus et Historiae’, 14, no. 29, 1997, pp. 139–70.
6. Keith Christiansen, 'Appendix: Technical Report on ‘The Cardsharps', Burlington Magazine’, CXXX, 1988, pp. 26–7.
7. Pigments analysed by EDX. For other Caravaggio ground cross-sections see Sergio Benedetti, 'Caravaggio's ‘Taking of Christ’, a Masterpiece Rediscovered', ‘Burlington Magazine’, CXXXV, 1993, pp. 731–41.
8. Bellori, 1672, cited in note 4, p. 209, in reference to the 1608 ‘Beheading of Saint John the Baptist’.
9. Raymond White and Jennifer Pilc, 'Analyses of paint media', ‘National Gallery Technical Bulletin’, 14, 1993, pp. 86–94.
10. See Gregori, cited in note 1, pp. 124–37.
11. See letters by Keith Christiansen and Sir Denis Mahon in the ‘Burlington Magazine’, CXXXIV, 1992, pp. 502–4.
12. See Christiansen 1990, cited in note 1, and 'Some Observations on Caravaggio's Two Treatments of the ‘Lute Player', Burlington Magazine’, CXXXII, 1990, pp. 21–6. For contemporary artists' practice of mechanical reproduction, see Linda Freeman Bauer, 'More evidence of artists' tracings', ‘Burlington Magazine’, CXXXVII, 1995, p. 38, and 'A letter by Barocci and the tracing of finished paintings', ‘Burlington Maga-Magazine’, CXXVIII, 1986, pp. 355–7.
13. One widely cited example is the model for the ‘Amor Vincit Omnia’, who was stated by Sandrart to have been a twelve-year-old boy ('einen Cupido in Lebens-Grosse nach gestalt eines ohngefehr zwölffjährigen Jünglings'). See Joachim von Sandrart, ‚Teutsche Academie der Edlen Bau- Bild- und Malerei-Künste‘, Nürnberg 1675, p. l90.
14. Giulio Mancini, ‘Considerazioni sulla pittura’, written 1614–21, reprinted (ed. A. Maruchi), Rome 1956, pp. 108–9; '... fa bene una figura sola, ma nella com-positione dell'historia et esplicar affetto, pendendo questo dall'immagination e non dall'osservanza della cosa, par ritrar il vero che tengon sempre avanti, non mi par che vi vagliano, essendo impossibil di mettere in una stanza una moltitudine d'huomini che rappre-sentin l'historia con quel lume d'una fenestre sola, et haver un che ride o pianga o faccia atto di / camminare e stia fermo per lasciarsi copiare, e cosi poi le lor figure, anchorchè habbia forza, mancano di moto e "d'affetti, di gratia, che sta in quell'atto d'operare come si dirà".
15. Keith Christiansen, 'Caravaggio and "L'esempio davanti del naturale" ', ‘Art Bulletin’, 68, 1986, p. 423.
16. Francesca Cappelletti and Laura Testa, 'I quadri di Caravaggio nella collezione Mattei: i nuovi documenti e risconti con le fonti', ‘Storia dell'arte‘, LXIX, 1990, pp. 75–84. See also Claudio Strinati et al., ‘Caravaggio e la collezione Mattei’, Milan 1995, pp. 118–19.
17. Cross-sections analysed by EDX.
18. The brown pigments used to sketch in the form over the dark ground contain no carbon particles and are thus not made more visible through infra-red examination.
19. See Mina Gregori, 'Come dipingeva il Caravaggio', in Gregori 1991, cited in note 1, pp. 13–29. For a full survey of documented examples of Caravaggio's incisions and their role, see Keith Christiansen, 'Caravaggio and "L'esempio davanti del naturale" ', ‘Art Bulletin’, 68, 1986, pp. 421–45.
20. Christiansen 1986, cited in note 19, p. 433.
21. Christiansen has described one incised line in the ‘Supper at Emmaus’ visible just below the shoulder in the left arm of Christ, which was not so apparent in later examination by the author and Gabriele Finaldi, Curator of Spanish and Later Italian Painting at the National Gallery; the picture is so highly finished that some ambiguities between putative incisions and level differences along contours of various painted areas are bound to occur.
22. See Raymond White and Jennifer Pilc, 'Analyses of paint media', ‘National Gallery Technical Bulletin’, 14, 1993, pp. 86–94.
23. Thomas Schneider, 'l'Orecchio del Caravaggio o come distinguere un originale da una copia', ‘Paragone’, 39–40, 1993, pp. 21–4.
24. Based on close visual inspection during its current restoration at the Opificio delle Pietre Dure e Laboratori di Restauro di Firenze.
25. For one example see David Stone, 'The Context of Caravaggio's ‘Beheading of Saint John’ in Malta', ‘Burlington Magazine’, CXXXIX, 1997, pp. 161–70.
26. I would like to thank Sr. Don Juan Martinez-Cuesta, Curator of Paintings at the Patrimonio Nacional, for allowing me to to examine the picture in Madrid.
27. Bellori 1672, cited in note 4, p. 211: 'e cercando in-sieme di placare il Gran Maestro, gli mandò in dono una mezza figura di Herodiade con la testa di San Giovanni nel bacino’. Mahon has suggested that the picture described by Bellori may not have been sent to Malta, and that it may have been among the pictures that were on the boat that took Caravaggio to Porto Ercole, where he died in 1610. See Mahon in Maurizio Marini, ‘Caravaggio’, Rome 1987, p. 510. However, more recent scholarship has linked the ‘Saint John’ now in the Borghese Gallery, Rome, with the picture recovered from the boat. See Vincenzo Pacelli, 'La morte di Caravaggio e alcuni suoi dipinti da documenti inediti', ‘Studi di storia dell'arte’, 2, 1991, pp. 167–88. His belongings were eventually recovered by the Spanish Viceroy of Naples, the Conte di Lemos, who is known to have returned to Spain in 1616. The ‘Salome’ now in the Patrimonio Nacional was accurately described and attributed in an inventory of the Spanish royal collection of 1666; a less certain reference to it appears in a royal collection inventory of 1636 but there is no clear link between it and any of the pictures in Caravaggio's possession at his death, nor is it mentioned in the personal history of the Conte di Lemos. See Mia Cinotti, ‘Caravaggio’, Bergamo 1983, p. 455. The association of that picture with the Spanish ‘Salome’ rests almost entirely on the coincidence of its lengthy Spanish provenance–less remarkable than might be assumed given the volume of commercial and artistic trade between Spain and Naples.
28. It is interesting to note, as has been pointed out by Dr Finaldi, that the extremely limited palette of the National Gallery picture is virtually the same as the colours of the Order of St John itself–brown, black and white.
29. See Christiansen 1990, cited in note 1, and Christiansen 1990, cited in note 12. See also Denis Mahon, 'The Singing Lute-player by Caravaggio from the Barberini ...Collection, painted for Cardinal del Monte', ‘Burlington Magazine’, CXXXII, 1990, pp. 4–20.

Series Editor: Ashok Roy

© National Gallery Publications Limited 1998
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First published in Great Britain in 1998 by National Gallery Publications Limited 5/6 Pall Mall East, London SW1Y 5BA

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ISBN 1 85709 220 1
ISSN 0140 7430
525270
Edited by Diana Davies and Jan Green