The Colors of Leonardo's Shadows

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The Colors of Leonardo’s Shadows ABSTRACT The author examines Leonardo da Vinci’s lifelong interest in the depiction of blurred, colored Francesca Fiorani shadows from the point of view of painting technique and optics. She analyzes Leonardo’s refinement of the oil technique to capture the instability of CELEBRATING LEONARDO DA VINCI colored shadows from the early Annunciation of 1472–1473 and examines the artist’s theoretical hadows have been fundamental to the art of which to my knowledge have not writings on shadows from the S 1490s onward. The author painting in the West, indeed inextricably connected to its been noticed before. The top and shows how Leonardo analyzed mythical origins. According to a story reported by Pliny and front of the lectern’s base present the blurred edges of colored repeated by countless authors, the first painting resulted from minor, albeit significant, differences shadows with the geometric tracing the outline of a shadow cast by a human figure on a in coloring, which can be attributed rigor that earlier authors wall. Later artists realized that the illusion of relief was created to Leonardo’s intention to repre- afforded only to the clear-cut edges of astronomical shadows. by adding internal shadows to the traced silhouette, and the sent the lectern’s orientation in re- She argues that the very kind depiction of shadows has since become a pictorial convention lation to the light sources of the of shadows that captured to suggest natural phenomena in painting [1]. painting. The top is yellowish, since Leonardo’s attention indicates No artist was more obsessed with shadows than Leonardo it is directly exposed to the red light his underlying pictorial con- (Figs 1 and 2). He painted the shadows that indicate model- cerns, despite the fact that of the late afternoon sun, while the his instructions often seemed ing, which he called “original shadows” (ombre originali). These relief-adorned front is bluish, since directed toward teaching a are the internal shadows that earlier painters such as Pietro it is exposed only to the indirect way of seeing rather than a Cavallini and Giotto had perfected and that earlier writers blue light of the sky. Leonardo must way of painting. such as Cennino Cennini had codified for workshop practice. have intensified these variations by But Leonardo also devoted endless attention to the colors that covering the image of the lectern shadows acquire by reflection from surrounding objects and with a varnish. His original varnish from their own light source, be it a candle, a window, the sky was lost long ago, but the existing varnish, which was applied or the sun. These reflected shadows, which he called “deriva- during an old and undocumented restoration, still effectively tive shadows” (ombre derivative), relate people and things to distinguishes the different colorings of the two surfaces. Placed each other, the viewer and the cosmos. Like Pliny, Leonardo prominently in the foreground, the lectern is a demonstration thought that “the first painting was only an outline that cir- piece of Leonardo’s skills in traditional and innovative picto- cumscribed the shadow of a man projected by the sun on a rial conventions. He carefully foreshortened the lectern, which wall” [2], but unlike that ancient author, who did not mention was inspired by a drawing or model from his master’s work- the light source of the shadow at the origins of painting, shop, according to the rules of linear perspective, thus demon- Leonardo explicitly stated that this ur-shadow was generated strating his mastery of that pillar of Renaissance painting. He by the sun. This added detail to the famous story is invaluable modeled in minute detail the lion’s-paw legs, acanthus leaves, in understanding Leonardo’s lifelong preoccupation with de- shells, volutes, garlands and rosettes to show his ability in us- picting the blurred, colored shadows generated outdoors by ing paint to suggest the three-dimensionality of sculpture, in- the combined light of the sun and the sky. deed to manifest visually the supremacy of painting over Leonardo’s earliest painting, the Annunciation of c. 1472– 1473, is justly famous for the depiction of outdoor shadows produced by the light of the setting sun, which casts its light Fig. 1. Leonardo da Vinci, Virgin and Child with Saint Anne, oil on from the left side of the painting, and by the diffuse light of wood, 168 × 130 cm, 1508–1517 (detail) (Paris, Musée du Louvre. the sky, which spreads across the entire scene (Fig. 3) [3]. Photo: Daniel Arnaudet. Photo © Réunion des Musées Seated in the garden of her palace, Mary casts a blurred Nationaux/Art Resource, NY.) shadow against the building to the right and behind her. Gabriel, who is himself the messenger of a shadow—an- nouncing to Mary that the Holy Spirit will come upon her by overshadowing her—projects his silhouette on the grass. Mary’s drapery is shadowed with intense dark blues that match in modeling and tone the dark red shadows of Gabriel’s robe. Bluish shadows appear on the angel’s white shirt, while the atmosphere and its reflections cause the blurring of outlines, features and colors in the background landscape. Internal shadows masterfully enhance the modeling of the marble base of Mary’s lectern. Mary’s lectern is remarkable also for its colored shadows,

Francesca Fiorani (scholar, academic), Art Department, University of Virginia, PO Box 400130, Charlottesville, VA 22904, U.S.A. E-mail: .

Fig. 2. Leonardo da Vinci, studies of original and derivative shadows generated by the atmosphere on a sphere placed between a window and a wall, pencil and ink, 0.213 × 0.148

CELEBRATING LEONARDO DA VINCI m, c. 1490. Paris, Bibliothèque de l’Institut de France, Ash- burnham Codex, complement to MS A (2185), fols. 13v-14r. (Photo: René-Gabriel Ojéda. Photo © Réunion des Musées Nationaux/Art Resource, NY.)

sculpture, which he later defended in his with yellow touches from the walls facing The shadows of bodies generated by the writings. He also painted colored shad- the viewer, which are bluish [4]. redness of the sun near the horizon are ows over the foreshortened and modeled Many years later, Leonardo wrote ex- always blue: and this is because of the 11th [proposition of the book on light form to place the lectern firmly on the tensively about the colored shadows that and shadow], where it is said: the surface painted surface through the representa- he had painted in the Annunciation and of any opaque object partakes the color tion of its lighting conditions. that had since become his innovative pic- of its object. Therefore, since the white- Similar colored shadows appear else- torial means of defining the location of ness of the wall is deprived of any color at all, it is tinged with the color of its ob- where in the Annunciation. The back- people and things in the atmosphere. In jects, which are, in this instance, the sun ground mountains are more yellowish on one written precept and its accompany- and the sky, because the sun reddens to- the side exposed to the sun’s rays and ing drawing, Why shadows cast by bodies on ward evening and the sky appears blue; more bluish on the opposite side, which white walls are blue at sunset, c. 1510 (Fig. and where on this wall the shadow does is illuminated by the sky. The gray walls 4), he explicitly equated the geometry of not see the sun, it will be seen by the sky, because of the 8th [proposition of the of the palace exposed to the sun are shadows with the geometry of reflected book] on shadows, which says: no lumi- slightly, but unmistakably, differentiated colors: nous body ever sees the shadows that it

Fig. 3. Leonardo da Vinci, Annunciation, oil on wood, 98 × 217 cm, c. 1472–1473. (Florence, Ufﬁzi Gallery. Photo © Scala/Art Resource, NY.) Leonardo depicted a full range of outdoor shadows: the cast shadows of Mary, Gabriel and of the lectern; the internal shadows of faces, draperies and the lectern; and the colored shadows of the lectern’s marble base, the angel’s robe and the background mountains.

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gether with a quantitative, or geometric, explanation, which was instead based on Euclidean optics. It is documented that, from the late 1480s onward, Leonardo read optical treatises and that he intended to write a book on light and shadow, to which he referred in this precept. No evidence exists that Leonardo was familiar with Aristotelian natural philosophy or Euclidean and medieval op- CELEBRATING LEONARDO DA VINCI tics in the 1470s, and, as far as one can tell, the shadows of his Annunciation were based entirely on artistic practice. Early in his artistic career, Leonardo grasped the distinct advantages of the oil Fig. 4. A drawing after Leonardo illustrating his precept Why shadows cast by bodies on white technique over the traditional tempera walls are blue at sunset. From Trattato della Pittura (Rome: Stamperia de Romanis, 1817) table VI, fig. 37. Leonardo’s original drawing of c. 1510 is known only through this copy of c. 1550 in depicting the instability of shadows by Francesco Melzi for Book Three of his compilation. The drawing analyzes the colored and the effects of the atmosphere [7]. By shadows generated by the sky and the sun on a sphere suspended in front of a white wall. trial and error, he learned how to dilute The sky vault is represented as a hemisphere on which the sun is placed. The drawing ren- colors in an oil-based medium, differen- ders effectively the spatial relations among light sources, opaque body and receiving surface, but inadequately represents shadows and their colors. tiate opaque pigments (corpi), semitrans- parent colors (mezzi corpi) and varnishes, and apply colors in multiple layers, which generates; therefore, the derivative on the wall (that is, those outside the blue he also knew how to vary incrementally shadow will project on the white wall with shadow) are reddish, since they are di- in tone and thickness. In the Annuncia- a blue color, because of the above-men- rectly exposed to the sun’s rays. The dia- tion, he painted shadows in the tradi- tioned 11th [proposition], and the shadow seen by the redness of the sun gram shows the geometry of colored tional Florentine way, building them up will partake its red color [5]. shadows correctly, although it is intrinsi- with darker colors from a middle ground cally ineffective in representing the col- rich with lead, but was nonetheless able Leonardo’s tortuous exposition is sub- ored shadows that were ultimately to render a voluminous, almost palpable stantially clarified in the drawing. In Leonardo’s main concern. atmosphere, which was vibrant with the Leonardo’s diagram, the sky vault (rep- In this precept, he proposed a “physi- color of the sun and with its own reflec- resented as a hemisphere) and the sun calist explanation” of colored shadows, to tions. Such an atmosphere was nowhere (represented as an extended light source use Michael Baxandall’s apt definition, to be found in contemporary paintings, on the hemisphere) illuminate a sphere adapting Aristotle’s observations on the not even in those by accomplished mas- suspended in front of a white wall. As the atmosphere and the physics of colors ters of the oil technique, such as the Pol- precept’s title indicates, Leonardo was in- (which Leonardo certainly knew after loaiolo brothers. terested in the color of the shadow cast 1500) to the phenomenon of colored Painting technique accounts also for by the sphere on the white wall. This cast shadows [6]. However, Leonardo pre- the increasingly subtle and undefined shadow is blue, since the sphere blocks sented this “physicalist explanation” to- shadows of Leonardo’s later paintings. the sun’s red light. The remaining areas

Fig. 5. Leonardo da Vinci, St. Jerome, 1480s (detail). (Photo © Musei Vaticani) This unﬁnished painting is instructive of Leonardo’s innovative technique for representing shadows. The painting’s general ground shadow (which Leonardo called a “universal shadow”), painted directly on the ground, is clearly visible in the saint’s bust, while the gradual buildup of light areas through multiple layers of mezzi corpi and glazes is evident in the saint’s shoulders, which show an advanced level of ﬁnish, and in the neck and face, which are only partially modeled.

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Fig. 6. Leonardo da Vinci, Studies on light and shadows, pencil and ink, 0.314 × 0.220 m, 1490–1491. (Paris, Bibliothèque de l’Institut de France, MS C [2174], fol. 21v and 14r, here reproduced according to Leonardo’s original pagination [fols. 16v and 17r]). The drawings at the bottom exemplify Leonardo’s graphic analysis of the blurred shadows. He depicted the causes and effects of the original and derivative shadows that a sphere illuminated by a round light source casts on itself, on a screen behind it and in the intervening atmosphere. Leonardo divided the surface of the light source (which is identiﬁed with the sun) and the surface of the opaque body into small units to analyze geometrically the blurred edges of shadows. (Photo René-Gabriel Ojéda. Photo © Réunion des Musées Nationaux/Art Resource, NY.)

As his unfinished paintings show (and the atmosphere throughout the entire might have ended here, in the realm of modern technical analysis confirms), he scene. painting technique, had not Leonardo reversed the traditional Florentine tech- Leonardo rarely wrote about his paint- embarked on a wide-ranging study of the niques and sketched deep shadows di- ing technique. Significantly, most of his theory of light and shadow that went far rectly on the panel’s gesso preparation, surviving precepts on the subject pertain beyond established artistic practice [9]. covering them with a primer; and he of- to the preparation, coloring and appli- From the mid-1480s to the end of his ten added and corrected shadows over cation of mezzi corpi and varnishes to life, he filled his notebooks with drawings the primer (Fig. 5). Over this “universal paint atmospheric shadows. He sug- and observations on the topic, which he shadow,” as Leonardo called the general gested painting shadows with “black, um- planned to put together in an illustrated ground shadow of a painting, he applied ber and a little lake, or just black chalk” book intended for artists in training. Al- multiple layers of glazes and mezzi corpi, and rendering facial shadows with mini- though it remains doubtful whether he which he made increasingly immaterial mal additions of red lake (lacca) or ever settled on a definitive way of organ- by reducing drastically, or eliminating al- Naples yellow (giallorino). He taught how izing such a book, it is known that at least together, lead white from their composi- to add intermediate shadows (ombre mez- twice, in 1490 and again around 1510, he tion (Color Plate D). At times, Leonardo zane) over the universal shadow, and how actively pursued the project. He went chose to mingle two superimposed, par- to mix black with other pigments using over his manuscripts, selected pertinent tially dried layers with his fingers to en- measuring spoons to obtain quantifiable notes and copied them in two new note- hance the blurring of shadows; but in and incremental tonal variations. He books: the surviving MS C, now at the other instances, he preferred to keep even figured out a practical method to Bibliothèque de l’Institut de France in the two layers separate so as to slightly verify the intensity of a painted shadow— Paris, and the lost Libro W. alter local tones. He varied the primer by casting a real shadow of his own fin- MS C, which Leonardo compiled from chromatically in different areas of the ger next to the painted shadow, to verify 23 April 1490 to January 1491, focuses on painting, but often used the same base that the intensity of the painted shadow the theory of light and shadow; and even color for sky and landscape, presum- matched the real one [8]. the apparently unrelated notes that it ably to enhance the pervasive effect of This analysis of Leonardo’s shadows contains on mechanics, ballistics and the

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Fig. 7. Leonardo da Vinci, Studies on the Formation of Pinhole Images, pencil and ink, 0.314 × 0.220 m, 1490–1491. (Paris, Bibliothèque de l’Institut de France, MS C [2174], fol. 10v-11r. In the instance of these two pages, Leonardo’s original pagination corresponds to the modern pagination.) The image generated by light from a round light source passing through an irregular pinhole acquires the circular shape of its source rather than the irregular shape of the hole through which it passes. This phenomenon was extensively discussed in ancient and medieval optical treatises, since it seemed to invalidate the axiom of the rectilinear propagation of light. (Photo René-Gabriel Ojéda. Photo © Réunion des Musées Nationaux/Art Resource, N.)

movements of water are pertinent to op- earlier source, Ibn Alhazen (965–1040 to the terminology of medieval dynamic tics [10]. Leonardo carefully designed A.D.), in particular his analogy between theory, where it defined the blow initiat- the layout of this unusually large note- the geometry of visual rays and the move- ing the movement of a body. Initially in- book of precious paper, integrating suc- ment of heavy bodies [12]. Indeed, the tended as a coherent book on light and cinct texts with highly finished drawings term “percussion” (percussione) that Leo- shadow that started with general propo- appropriately modeled with nuanced nardo used to indicate the action of light sitions, followed by case studies of in- shadows (Fig. 6). He presented his draw- rays on surfaces and on the eye belonged creasing complexity, MS C soon became ings as visual records of his own optical experiments, although it is more likely that he only rendered famous optical Fig 8. Two drawings after Leonardo illustrating his precept On that part of a body which will be problems described by earlier authors. most illuminated by a light of even quality, from Trattato della Pittura (Rome: Stamperia de For example, his drawings of the forma- Romanis, 1817) table XII, figs. 44 and 45. Leonardo’s original drawings of c. 1510 are known only through these copies of c. 1550 by Francesco Melzi for Book Five of the Libro di pittura. tion of pinhole images (Fig. 7) depict, al- The drawings analyze the geometry of atmospheric reflection on a sphere both in the pres- most step by step, the discussion that ence and in the absence of direct sunlight. medieval writers, especially Biagio Pela- cani of Parma (d. 1416), devoted to this thorny issue that seemed to contradict the axiom of the rectilinear propagation of light [11]. The drawings pertaining to the shadow of a circle or shadows generated by a light source larger than the opaque body seem to be taken directly from Euclid’s Optics. Even the notes on ballistics, mechanics and the movements of water may have been inspired by an

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rentine artistic circles. Lorenzo Ghiberti had access to a vernacular translation and transcribed extensive sections of it in his Commentarii. Pelacani’s Questiones super perspectivam was generously illustrated but was available only in Latin. It is documented that Leonardo read Alhazen’s and Pelacani’s treatises in Milan in the 1480s or 1490s. But the shadows of the Annunciation raise the possibility that CELEBRATING LEONARDO DA VINCI Leonardo’s first encounter with optical writings, at least with Alhazen’s, might have occurred at an earlier date than is usually acknowledged. Leonardo must have given consider- able thought to how to integrate his physicalist and geometric analysis of shadows, Fig. 9. A drawing after Leonardo illustrating his precept On that part of a body which will be eventually leaving to Melzi the difficult most illuminated by a light of even quality, from Trattato della Pittura (Rome: Stamperia de task of finding the proper order for his Romanis, 1817) table XI, fig. 36. Leonardo’s original drawing of c. 1510 is known only texts on the subject [16]. In the Libro di through this copy of c. 1550 by Francesco Melzi for Book Five of the Libro di pittura. The pittura, the discussion on colors and the drawing analyzes the geometry of shadows generated by the sky and the sun on an architec- atmosphere precedes the geometry of tural element. Leonardo had painted identical shadows in the background of his Adoration of the Magi 30 years earlier (see Fig. 10). shadows: Books Two and Three are devoted to “physicalist explanations” ex- emplified by the precept Why in twilight the temporary repository of materials ments, variety and intensity of shadows shadows on white objects are blue (see above), that he intended to reorganize later on. recur in both manuscripts. Leonardo re- which indeed Melzi copied in this section The lost Libro W, compiled around garded shadows as infinite, since shadows of his compilation. The geometry of light 1510, was Leonardo’s last attempt at or- are seen “across a continuous quantity, and shadow is instead presented in Book dering his notes on light and shadow. The which is in itself infinitely divisible” [14], Five. This ordering might correspond to layout, sequence and state of completion a notion of continuous quantity that he Leonardo’s intentions. Certainly it con- of this lost book are unknown, but its gen- borrowed from Aristotelian natural phi- forms to the hierarchical ordering of eral content can be roughly recon- losophy. He followed Alhazen’s De as- knowledge in the Renaissance, which structed from the Libro di pittura, the pectibus or, at the very least, Biagio manuscript assembled around 1550 by Pelacani of Parma’s Questiones super per- Fig. 10. Leonardo da Vinci, Adoration of the Francesco Melzi, one of his pupils and the spectivam in explaining shadows in rela- Magi (unfinished), undercoat of paint on heir of his manuscripts, to fulfill Leo- tion to the quality of the air and the wood, 243 × 246 cm, 1481–1482 (detail). nardo’s desire to publish a book on paint- atmosphere as well as to optical geome- (Uffizi Gallery, Florence. Photo © Erich Lessing/Art Resource, NY.) ing. Melzi’s compilation, known today try [15]. as MS Urb. Lat. 1270 in the Biblioteca Alhazen’s main contribution to optics Apostolica Vaticana, is divided into eight was his approach to light, shadows, col- topical books concerned with the com- ors and vision from the double perspec- parison of the arts, aerial and color tive of Aristotelian natural philosophy perspective, pictorial composition, the and Euclidean geometry. He discovered movements of the body, the theory of the laws of refraction and dealt exten- light and shadow and the representation sively with multiple light sources, the den- of trees, clouds and the horizon. The sity of the atmosphere, the dispersion of precepts assembled in Book Five, titled light in its constituent colors and the col- On Shadow and Light (De ombra e lume), are ors of sunset. Alhazen’s De aspectibus largely unrecorded in Leonardo’s origi- formed the basis of medieval optics, al- nal manuscripts, a fact that seems to con- though by the time of the late 14th cen- firm their origin in the lost Libro W, which tury, Biagio Pelacani of Parma was one of indeed Melzi mentioned among his the few who truly understood it. He sources for the Libro di pittura (Fig. 8) adapted and modified Alhazen’s argu- [13]. ment that the perception of the appar- Judging from MS C and Melzi’s Book ent size of objects does not depend solely Five, Leonardo’s concerns, procedures on the proportion of visual angles, as Eu- and method of inquiry remained funda- clidean optics maintained, but follows mentally unchanged from 1490 to 1510. the proportion of the distance between Occasionally the graphic language he eye and object. This notion was funda- used in his diagrams varied, becoming at mental to the invention of artistic per- once more precise and abstract, as in the spective. Alhazen’s and Pelacani’s texts case of the representation of the sky vault were available in Florence in the 15th and the sun (Figs 6 and 8), but otherwise century, and De aspectibus was even trans- similar topics pertaining to the move- lated into Italian and circulated in Flo-

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placed natural philosophy and physics not similar entities from the point of view References and Notes above geometry and mathematics. It was of natural philosophy, he treated them 1. Pliny, Natural History, H. Rackman, trans. (Cam- Melzi’s intention that the Libro di pittura similarly since, in his view (based on Al- bridge and London: Loeb Classic Library, 1952) should preserve and hand down to pos- hazen’s writings), shadows and colors are XXXV, V. On shadows in Western philosophy, art and culture, see T. Da Costa Kaufmann, “The Perspective terity Leonardo’s unique contribution to affected by the same optical rules based of Shadows: The History of the Theory of Shadow the science of painting—-that is, a theory on the geometry of reﬂection. Shadows Projection,” Journal of the Warburg and Courtauld In- stitutes 38 (1975) pp. 258–287; M. Baxandall, Shadows of blurred shadows and their colors based are always colored and, conversely, colors and the Enlightenment (New Haven, CT, and London: on optics, which, in turn, combined are always shadowed. In his paintings, he Yale Univ. Press, 1995); V. Stoichita, A Short History of physics with geometry. It is the systematic rendered blurred shadows by means of the Shadow (London: Reaktion Books, 1997); R. Casati, Shadows: Unlocking Their Secrets, from Plato to use of these two branches of natural phi- numerous layers of mezzi corpi and var-

Our Time (New York: Vintage, 2003); and D. Sum- CELEBRATING LEONARDO DA VINCI losophy to painting that transformed nishes, while the intimate connection be- mers, Real Spaces (London: Phaidon, 2003) pp. Leonardo’s science of painting into a tween shadows and colors translated into 251–548. philosophical investigation. the colored shadows that invariably char- 2. Leonardo da Vinci, Manoscritti dell’Institut de France, A closer examination of MS C and of acterized his paintings from the Annun- A. Marinoni, ed., 12 vols. (Florence: Giunti, 1986– 1990) Vol. 1: Manoscritto A, fol. 97 v. This note is dated Book Five of the Libro di pittura reveals ciation onward (Figs 9 and 10). c. 1492. that the real novelty of Leonardo’s analy- Leonardo’s obsession with shadows is 3. On Leonardo’s Annunciation, see D.A. Brown, sis of shadows resided in the specific kind traceable from his earliest works. This Leonardo da Vinci: Origins of a Genius (New Haven, CT, of shadows he investigated. Like earlier preoccupation originated in his own and London: Yale Univ. Press, 1998) pp. 75–99; L’An- authoritative optical treatises, Leonar- acute observations of natural phenom- nunciazione di Leonardo: La montagna sul mare, A. Na- tali, ed. (Milan: Silvana Editoriale, 2000); P.C. do’s writings moved from the general to ena and, at least initially, developed Marani, Leonardo da Vinci: The Complete Paintings (New the particular, but unlike earlier authors within the practice of painting. His skill- York: Abrams, 2003) pp. 48–61. Seminal on he did not examine the shadows of as- ful mastery of the oil technique made it Leonardo’s colors is J. Shearman, “Leonardo’s Color and Chiaroscuro,” Zeitschrift für Kunstgeschichte 25 tronomy—that is, shadows with clearcut possible for him to translate in paint his (1962) pp. 13–47. An important reassessment is C. outlines generated by astronomical bod- observations on ever-changing shadows. Farago, “Leonardo’s Color and Chiaroscuro Recon- sidered: The Visual Force of Painted Images,” Art Bul- ies placed at a great distance from the But his interest must have been piqued letin 73, No. 1 (1992) pp. 63–88. On Leonardo’s viewer. In his later years, he wrote about quite early, possibly much earlier than painting technique, see A. Del Serra, “L’incanto del- astronomical shadows and, at some point, thus far acknowledged, by readings of an- l’Annuncio. Rendiconto di restauro,” in Natali [3] pp. 95–111. On shadows’ symbolism in the story of even thought of concluding his book on cient and medieval optical treatises. the annunciation, see Stoichita [1] pp. 67–87, who light and shadows with a discussion of the Eventually, his investigation of shadows however did not discuss Leonardo’s painting. moon and the sun. But his lifelong in- and their colors achieved an unprece- 4. One of Leonardo’s innovations was to increase the terest was in observing and painting the dented breadth of scope, one that was ap- luminosity of the dull and light-absorbing color gray blurred edges of shadows that can be per- propriate for a natural philosopher, by painting the gray over a vibrant pink primer, which is now visible underneath the centuries-old surface ceived in suffused light at a close distance, although it never lost its relevance to color (Del Serra [3] p. 104). or at least a distance graspable by the hu- painting. For Leonardo, the science of 5. Leonardo da Vinci, Libro di pittura, C. Pedretti and man eye (see Fig. 1). The very kind of painting was so fundamentally based on C. Vecce, eds. 2 vols. (Florence: Giunti, 1995) Vol. 2, shadows that captured Leonardo’s atten- optics that he based his own writings No. 467. The original precept and accompanying tion indicates his underlying pictorial about art on optical treatises. Like an- drawing by Leonardo are lost but they are documented in the Libro di pittura compiled by his pupil concerns, even though these concerns cient and medieval optical texts, his writ- Francesco Melzi c. 1550 (Vatican, Biblioteca Apos- are rarely spelled out and despite the fact ings were instructions of increasing tolica Vaticana, MS Urb. Lat. 1270, fol. 148v). that his instructions often seem aimed at complexity, illustrated graphically and 6. Baxandall [1], p. 115, singled out Leonardo’s teaching a way of seeing rather than a way imparted directly to the apprentice, one “physicalist explanation” in this precept. On of painting. Furthermore, he studied and at a time. However, these precepts did not Leonardo’s optics, theory of colors, reflections and shadows see Rzepinska, “Light and Shadow in the drew blurred shadows with the geomet- instruct the student of painting in work- Late Writings of Leonardo da Vinci,” Raccolta vin- ric rigor afforded to astronomical shad- shop practices, such as the mixing of col- ciana 19, pp. 259–266 (1962); Shearman [3]; C. Pe- dretti, Leonardo da Vinci on Painting: A Lost Book (Libro ows. Ancient and medieval optical ors or the foreshortening of figures, but A) (Berkeley and Los Angeles: University of Califor- treatises defined the clear-cut outlines of rather on how to represent natural phe- nia Press, 1964) pp. 146–151; Kaufman [1] pp. shadows geometrically, but only Leo- nomena such as shadows, reflected col- 267–275; C. Lindberg, Theories of Vision from Al-Kindi to Kepler (Chicago: University of Chicago Press, 1976) nardo reserved the same geometric, ors and blurred outlines—-that is, on pp. 58–86; M. Kemp, “Leonardo and the Visual quantitative treatment for blurred edges. natural phenomena that give us invalu- Pyramid,” Journal of the Warburg and Courtauld Insti- Aristotle had defined the infinite divisi- able, though subliminal, information on tutes 40, pp. 128–149 (1977); J. Ackerman, “Leonardo’s Eye,” Journal of the Warburg and Courtauld bility of continuous quantities, but it was our place in the world and that, for Institutes 41, pp. 108–146 (1978); C. Malterse, “Gli Leonardo’s idea to apply this Aristotelian Leonardo, gave universal rules to the sci- studi di Leonardo sulle ombre tra la pittura e la scienza,” Arte lombarda 67, pp. 95–101 (1983); C. Mal- notion to the graphic analysis of shadows. ence of painting. tese, “Leonardo e la teoria dei colori,” Römisches In drawings from the late 1480s onward, Jahrbuch für Kunstgeschichte 20, pp. 209–219 (1983); J. Leonardo divided the surface of light Bell, “Color Perspective, c.1492,” Achademia Leonardi Vinci 5, pp. 64–77 (1992); Farago [3]; M. Hall, Color sources and opaque bodies into small Acknowledgments and Meaning: Practice and Theory in Renaissance Paint- units of identical quantity, connected ing (New York and Cambridge, MA: Cambridge Univ. each unit of the light source to the Research for this essay was funded by the Carl H. and Press, 1992); J. Bell, “Leonardo and Alhazen: The Martha S. Lindner Center for Art History at the Uni- Cloth on the Mountain Top,” Achademia Leonardi opaque body and its partitions, and cal- versity of Virginia. My deepest thanks to Francesco Vinci 6, pp. 108–111 (1993); J. Bell, “Aristotle as a culated graphically, unit by unit, the in- Buranelli, Director of the Vatican Museums, and Source for Leonardo’s Theory of Color Perspective tensity of shadows and their blurred Arnold Nesselrath, Director of Byzantine, Medieval after 1500,” Journal of the Warburg and Courtauld Insti- and Renaissance Art at the Vatican Museums, for per- tutes 56, pp. 100–118 (1993); A. Nagel, “Leonardo and edges (Figs 2, 6 and 9). In his writings, mission to examine Leonardo’s St. Jerome; and to An- sfumato,” Res 24, pp. 7–20 (1993); Baxandall [1] pp. Leonardo also discussed the intertwining tonio Natali, Director of the Uffizi Gallery, and 151–155; Casati [1] pp. 164–169; and F. Ferhenbach, Angelo Tartuferi, Curator of Medieval and Early Re- “Veli sopra veli. Leonardo und die Schleier,” in of shadows and colors. Even though he naissance Painting at the Uffizi Gallery, for permis- Ikonologie des Zwischenraums. Der Schleier als Medium knew well that shadows and colors were sion to examine Leonardo’s Annunciation. und Metapher, J. Endres, B. Wittmann and G. Wolf,

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eds. (Munich: Wilhelm Fink Verlag, 2005) pp. of Pinhole Images in the Fourteenth Century,” 15. On Alhazen’s optics see G. Vescovini, Studi sulla 121–147. Archive for History of Exact Sciences 6, pp. 299–325 prospettiva medievale (Turin: G. Giappichelli, 1965) pp. (1970). 113–136; Lindberg [6] pp. 58–86; and Alhazen, The 7. Leonardo’s highly debated painting technique has Optics of Ibn-al-Haytham: Books I–III: On Direct Vision, been greatly clarified in a recent significant contri- 12. Alhazen, De aspectibus, in Opticae thesaurus: Alhazeni A.I. Sabra, ed. and trans. (London: Warburg Insti- bution, Mona Lisa: Inside the Painting, J.P. Mohen, M. Arabis libri septem, F. Risner, ed. (Basel, 1572). Reprint tute, 1989). On Pelacani’s optics, see Vescovini, pp. Menu and B. Mottin, eds. (New York: Abrams, 2006), with an introduction by D. Lindberg (New York: 239–268; Lindberg [6] pp. 130–132. On the diffusion on which my discussion is based. To the earlier im- Johnson Reprint Corp., 1972) pp. 112–113, and Lind- of Alhazen’s and Pelacani’s texts in 15th-century Flo- portant studies listed in Mona Lisa should be added berg’s introductory comments, p. xviii. On the in- rence, see G. Vescovini, “Contributo per la fortuna L. Syson-Billinge, “Leonardo da Vinci’s Use of Un- fluence of medieval dynamics on Leonardo’s di Alhazen in Italia,” Rinascimento 5, pp. 17–49 (1965); der-Drawing in the Virgin of the Rocks at the National writings, see F. Fehernbach, Licht und Wasser: Zur Dy- G. Vescovini, Arti e filosofia nel secolo XIV: Studi sulla Gallery and St. Jerome in the Vatican,” Burlington Mag- namik naturphilosophischer Leitbilder im Werk Leonardo tradizione aristotelica e i moderni (Florence: Vallecchi, azine 147, No. 1228, 450–463 (2005); and M. Seracini, da Vincis (Tübingen: Wasmuth, 1997). 1977) pp. 101–212. Alhazen’s treatise on shadows,

CELEBRATING LEONARDO DA VINCI “Indagini diagnostiche sulla Adorazione dei magi di however, was unknown in the Latin west (Alhazen Leonardo da Vinci,” in La mente di Leonardo: Nel lab- 13. Melzi’s compilation is edited in Leonardo [5]. [12] p. vi). oratorio del genio universale, P. Galluzzi, ed. (Florence: The drawings reproduced here as Figs. 8 and 9 are Giunti, 2006) pp. 339–357. not Leonardo’s originals, which are lost, but copies 16. Farago [3] detected a recurrent sequence in documented in Melzi’s Libro di pittura (Vatican, Bib- Leonardo’s manuscripts relating to the organization 8. Leonardo’s precepts quoted in this paragraph are lioteca Apostolica Vaticana, MS Urb. Lat. 1270, fol. of his book on painting, which she named the “trat- in Leonardo [5] Vol. 2, Nos. 514, 758, 756 and 761. 198v and 202r). Melzi’s compilation is edited in tato sequence.” Farago [13] analyzes the relation be- On Leonardo’s pigments for shadows, see Mona Lisa Leonardo [5]. Melzi listed both Libro W and MS C tween Leonardo’s “trattato sequence” and Melzi’s [7] p. 62. among his sources for the Libro di pittura (MS C is compilation. 9. Selections of Leonardo’s precepts on light, shad- listed as “MS G”). Textual analysis comparing Book ows and colors are in Leonardo [5] Vol. 2, pp. Five of the Libro di pittura to Leonardo’s original man- Manuscript received 24 June 2007. 361–467; The Notebooks of Leonardo da Vinci, J.P. uscripts showed that Melzi copied precepts on light Richter, ed., 2 vols. (New York: Dover, 1970) Vol. 1, and shadow from Leonardo’s MS A of c. 1490, such Francesca Fiorani is Associate Professor of Art as the drawing in Fig. 2, but did not use MS C at all, pp. 67–166; The Literary Works of Leonardo da Vinci, J.P. History at the University of Virginia and an Richter, ed., with commentary by C. Pedretti, 2 vols. presumably because he could consult a later compi- (Berkeley and Los Angeles: University of California lation on light and shadow, possibly the lost Libro W. expert on the relationship between art, science Press, 1977) Vol. 1, pp. 151–226; and Leonardo on On the relations between MS C and Libro W, see Pe- and technology in Renaissance and Baroque Painting, M. Kemp and M. Walker, eds. (New Haven, dretti [9] pp. 146–151. On Melzi’s editorial work, see Europe. She has written extensively on Re- C. Pedretti, “Introduzione,” in Leonardo [5] pp. CT, and London: Yale Univ. Press, 1989) pp. 47–115. naissance mapping, representations of space, On the legacy of Leonardo’s shadows, see F. Fiorani, 11–79; C. Vecce, “Nota al testo,” in Leonardo [5] pp. “The Theory of Shadow Projection and Aerial Per- 83–123; and C. Farago, “How Leonardo da Vinci’s optics, shadows and color theory. The author spective: Leonardo, Desargues and Bosse,” in Desar- Editors Organized His Treatise on Painting and How of The Marvel of Maps: Art, Cartography gues en son temps, J. Dhombres and J. Sakarovitch, eds. Leonardo Would Have Done It Differently,” in The and Politics in Renaissance Italy (Yale (Paris: A. Blanchard, 1994) pp. 267–282. Treatise on Perspective: Published and Unpublished, L. Massey, ed., Studies in the History of Art 59, pp. 20–52 Univ. Press, 2005) and the director of the dig- 10. Leonardo [2] Vol. 3: Il manoscritto C. (2003). ital project Leonardo da Vinci and His Treatise on Painting (Institute for Ad- 11. On pinhole images, see D. Lindberg, “The The- 14. Leonardo da Vinci, Il codice atlantico della Biblioteca vanced Technology in the Humanities, Uni- ory of Pinhole Images from Antiquity to the Thir- Ambrosiana di Milano, A. Marinoni, ed. (Florence: teenth Century,” Archive for History of Exact Sciences 5, Giunti, 1973–1980) fol. 586 b (English translation versity of Virginia), she is now completing a pp. 154–176 (1968); and D. Lindberg, “The Theory from Notebooks [9] Vol. 1, No. 548). book on Leonardo’s shadows.

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