LATE MEDIEVAL AND EARLY RENAISSANCE NORTHERN EUROPE FRAMING THE ERA Rogier van der Weyden and Saint Luke In the 15th century, Flanders—a region corresponding to what is today Belgium, the Netherlands, Luxembourg, and part of northern France (map 20-1)—enjoyed widespread prosperity. Successful merchants and craft guilds joined the clergy and royalty in commissioning artists to produce works for both public and private venues. Especially popular were paintings prepared using the recently per-fected medium of oil-based pigments, which soon became the favored painting medium throughout Europe. One of the early masters of oil painting was Rogier van der Weyden (ca. 1400–1464) of Tournai in present-day Belgium. Rogier made Brussels his home in 1435 and soon thereafter painted Saint Luke Drawing the Virgin (fig. 20-1), probably for the city’s artists’ guild, the Guild of Saint Luke. Luke was the patron saint of artists because legend said he had painted a portrait of the Virgin Mary (see “Early Christian Saints,” pages 246–247). Rogier’s subject was therefore perfectly suited for the head-quarters of a painters’ guild. It shows Luke (his identifying attribute, the ox, is at the right; see “The Four Evangelists,” page 331) at work in the kind of private residence that wealthy Flemish merchants of this era owned. Mary has miraculously appeared before Luke and invited him to paint her portrait as she nurses her son. The saint begins the process by making a preliminary drawing, the same process Rogier himself would have used when he began this commission. The painting thus not only honors Luke but also pays tribute to the profession of painting in Flanders (see “The Artist’s Profession in Flanders,” page 580) by documenting the preparatory work required before artists can begin painting the figures and setting. The subject also draws attention to the venerable history of portrait painting. A rare genre dur-ing the Middle Ages, portraiture became a major source of income for Flemish artists, and Rogier was one of the best portrait painters (fig. 20-12A) in Flanders. In fact, some scholars have suggested that Rogier’s Saint Luke is a self-portrait, identifying the painter with the first Christian artist and under-scoring the holy nature of painting. Saint Luke Drawing the Virgin is also emblematic of 15th-century Flemish painting in aiming to record every detail of a scene with loving fidelity to optical appearance, seen here in the rich fabrics, the patterned floor, and the landscape visible through the window. Also characteristic of Flemish art is the imbuing of many of the painting’s details with symbolic significance. For example, the carved armrest of the Virgin’s bench depicts Adam, Eve, and the serpent, reminding the viewer that Mary is the new Eve and Christ the new Adam who will redeem humanity from Adam and Eve’s Original Sin. 567 Copyright 2021 Cengage Learning. All NORTHERN EUROPE IN THE 15TH CENTURY As the 15th century opened, Rome and Avignon were still the official seats of two competing popes (see “The Great Schism,” page 423), and the Hundred Years’ War (1337–1453) between France and England still raged. The general European movement toward centralized royal governments, begun in the 12th century, continued apace, with a corresponding waning of feudalism. A ris-ing merchant class, whose success depended on individual effort and talent instead of inherited nobility, spawned a new economic system—the early stage of European capitalism. In response to the financial requirements of trade, new credit and exchange systems created a network of enterprising European cities. Trade in money accompanied trade in commodities, and the former financed industry. Both were in the hands of international banking compa-nies, such as those of Jacques Coeur in Bourges (fig. 13-31) and the Medici in Florence (see “The Medici,” page 593). In 1460, Flemish entrepreneurs established the first international commercial stock North Sea E NG L AN D London English Channel Haarlem Ghent Bruges Tournai Amsterdam Nijmegen Louvain Cologne Antwerp Brussels Creglingen Würzburg Paris F R A N C E Tours POITOU Poitiers ATLANTIC OCEAN AUVERGNE Avignon Florence Lucca PAPAL STATES S PA I N 0 0 150 150 300 kilometers Mediterranean Sea 300 miles Rome Tyrrhenian Sea Adriatic Sea OT TOMAN EMP I R E Bourges BERRY Melun Nemours Colmar Dijon Beaune Lake Geneva Geneva Venice Nancy Strasbourg Buxheim H O L Y R O M A N E M P I R E Nuremberg H U NGA RY Kraków Magdeburg PO L AN D exchange in Antwerp. In fact, the French word for stock market (bourse) comes from the name of the van der Beurse family of Bru-ges, the wealthiest city in 15th-century Flanders. Art also thrived in northern Europe during this time, under royal, ducal, church, and private patronage. Two developments in particular were of special significance: the adoption by Rogier van der Weyden (fig. 20-1) and his contemporaries of oil-based pig-ment as the preferred medium for painting, and the blossoming of printmaking as a major art form, which followed Johannes Guten-berg’s invention of moveable type and the printing press. These new media had a dramatic influence on artistic production both north and south of the Alps. THE FRENCH DUCAL COURTS In the 15th century, Flanders was not an independent state but a region under the control of the duke of Burgundy, the ruler of the fertile east-central region of France still famous for its wines (map 20-1). Duke Philip the Bold (r. 1363–1404) was one of four MAP 20-1 France, the duchy of Burgundy, and the Holy Roman Empire in 1477. Late MedievaL and earLy renaissance northern europe 1395–1425 ■ Claus Sluter carves life-size statues of biblical figures with portraitlike features, and Jacques de Baerze and Melchior Broederlam carve and paint the Retable de Champmol for Philip the Bold, duke of Burgundy ■ The Limbourg brothers expand the illusionistic capabilities of manuscript illumination for Jean, duke of Berry 1425–1450 ■ In Flanders, Robert Campin, Jan van Eyck, and Rogier van der Weyden use oil paints to record the exact surface appearance of objects, fabrics, and faces ■ ■ Flemish painters establish portraiture as a major art form German graphic artists pioneer wood-cut printing, making art affordable to the masses 1450–1475 ■ The second generation of Flemish master painters—Petrus Christus, Dieric Bouts, and Hugo van der Goes—continues to use oil paints for altarpieces featuring naturalistic repre-sentations of religious themes ■ In Germany, Johannes Gutenberg invents moveable type and prints the first Bibles on a letterpress 1475–1500 ■ In Flanders, Hans Memling specializes in paintings of the Madonna and Child and portraits of wealthy merchants ■ The Late Gothic style lingers in Ger-many in the large wood altarpieces carved by Veit Stoss and Tilman Riemenschneider ■ Martin Schongauer becomes the first Northern European master of metal engraving sons of King John II (r. 1350–1364) of France. In 1369, Philip mar-ried Margaret de Mâle, the daughter of the count of Flanders, and acquired territory in the Netherlands. Thereafter, the major source of Burgundian wealth was Bruges, the city that made Burgundy a powerful rival of France, which then, as in the Gothic age, was a much smaller kingdom geographically than the modern nation-state. Bruges initially derived its wealth from the wool trade, but soon expanded into banking, becoming the financial clearinghouse for all of northern Europe. Indeed, Bruges so dominated Flanders that the duke of Burgundy eventually chose to make the city his capital and moved his court there from Dijon. Due to the expanded territory and the prosperity of the duchy of Burgundy, Philip the Bold and his successors were probably the most powerful northern European rulers during the first three quarters of the 15th century. Although members of the French royal family, they usually supported England during the Hundred Years’ War because they relied on English raw materials for their wool industry. At times, the dukes of Burgundy controlled much of northern France, including Paris, the seat of the French monarchy. At the height of Burgundian power, the ducal lands stretched from the Rhône River to the North Sea. chartreuse de champmol The great wealth the Burgundy court acquired enabled it to become a significant patron of the arts. Burgundian dukes fully appreciated that artworks could support their dynastic and political goals as well as adorn their castles and townhouses. Philip the Bold’s grandest artistic enterprise was the Chartreuse de Champmol, near Dijon. A chartreuse (“charter house” in English) is a Carthusian monastery. The Carthusian order, founded by Saint Bruno (ca. 1030–1101) in the late 11th century at Chartreuse, near Grenoble in southeastern France, consisted of monks who devoted their lives to solitary liv-ing and prayer. Unlike monastic orders that earned income from farming and other work, the Carthusians generated no revenues. Philip’s generous endowment at Champmol was therefore the sole funding for an ambitious artistic program inspired by the French royal abbey at Saint-Denis (see “Abbot Suger and the Rebuilding of Saint-Denis,” page 383, and fig. 13-1), the burial site of the French kings. The duke’s choice for architect was Drouet de Dammartin, who had worked for his brother King Charles V (r. 1364–1380) on the Louvre (fig. 20-6), the French royal palace in Paris. In 1372, Philip appointed as chief sculptor the Netherlandish master Jean de Marville (d. 1389), who had also worked for Charles V, but at Rouen Cathedral. Emulating the royal burials at Saint-Denis, Philip decided to create at the Dijon chartreuse a ducal mausoleum that would serve both as a means of securing salvation in perpetuity for the ducal family (the monks prayed continuously for their souls) and as a dynastic symbol of Burgundian power. Claus Sluter. In 1389, following the death of Jean de Marville, Philip placed the Neth-erlandish sculptor Claus Sluter (ca. 1360–1406) of Haarlem in charge of the sculptural program (figs. 20-2 and 20-2a). Sluter had joined the Chartreuse de Champmol sculp-ture workshop as Jean’s assistant in 1385. For the portal (fig. 20-2A) of the monastery’s chapel, Sluter’s workshop produced stat-ues of the duke and his wife kneeling before the Virgin and Child. For the cloister, Sluter designed a large sculptural fountain located in a well (fig. 20-2). The well itself served as a water source for the monastery, but Sluter’s fountain did not spout water because the Carthusian commitment to silence and prayer would have precluded anything producing sound. The Well of Moses features statues of Moses and five other Old 20-2a Sluter, Chartreuse de Champmol portal, 1390–1393. 1 ft. 20-2 Claus Sluter, Well of Moses, Chartreuse de Champmol, Dijon, France, 1396–1406. Asnières limestone, painted and gilded by Jean Malouel, Moses 69 high. The Well of Moses, a symbolic fountain of life made for the duke of Bur-gundy, originally supported a sculpted Crucifixion group. Sluter’s figures recall French Gothic jamb statues, but are far more realistic. Testament prophets (David, Daniel, Isaiah, Jeremiah, and Zachariah) ringing a base that once supported a 25-foot-tall group of Christ on the cross mourned by Mary Magdalene, joined perhaps by the Vir-gin Mary and John the Evangelist. Art historians usually describe the Well of Moses as a fons vitae, a fountain of everlasting life, in which the blood of the crucified Christ, symbolized by water, flows down into a basin, and anyone who drinks from the fountain is redeemed. Sluter incorporated The six prophets have almost portraitlike features and distinct individual personalities and costumes. For example, David is an elegantly garbed Gothic king and Moses an elderly horned prophet (compare fig. 12-38) with a waist-length beard. Sluter intensely studied the natural appearance of faces and fabrics in order to sculpt the biblical figures in minute detail. Heavy draperies with voluminous folds swathe the life-size statues. Sluter succeeded in making their difficult, complex surfaces seem remarkably natural-istic. He enhanced this effect by skillfully differentiating textures, from coarse drapery to smooth flesh and silky hair. Paint, much of which has flaked off, further augmented the naturalism of the figures. (The painter was Jean Malouel [ca. 1365–1415], another Netherlandish master.) This fascination with the specific and tan-gible in the visible world became one of the chief characteristics of 15th-century Flemish art. Retable de Champmol. Philip the Bold also commissioned a major altarpiece—the Retable de Champmol (figs. 20-3 and 20-4)—for the main altar in the chapel of the Chartreuse. A collaborative project between two Flemish artists, this altarpiece consisted of a 1 ft. 20-3 Jacques de Baerze, Retable de Champmol (open), from the chapel of the Chartreuse de Champmol, Dijon, France, installed 1399. Wood, center section 59 5 3 40 × 89 3 1 40. Musée des Beaux-Arts, Dijon. Worshipers could view the interior of the Champmol altarpiece on Sundays and feast days. Jacques de Baerze carved three scenes of Jesus’s life centered on the Crucifixion, a fitting backdrop for the Eucharist. 20-4 Melchior Broederlam, Retable de Champmol (closed), from the chapel of the Chartreuse de Champmol, Dijon, France, installed 1399. Oil and tempera on wood, each wing 59 5 3 Arts, Dijon. 40 × 49 1 1 40. Musée des Beaux-This early example of oil painting attempts to represent the three-dimensional world on a two-dimensional surface, but the gold background and flat halos recall medieval pictorial conventions. 1 the symbolism of the fons vitae in his waterless fountain, in which the viewer must imagine Christ’s blood stream-ing down over grieving angels and the Savior’s prophetic predeces-sors. Although the models for the Old Testament figures may have been French Gothic cathedral portal statues, as was certainly the case for the Dijon chapel statues (fig. 20-2A), the inspiration for the Well of Moses prophets may have come more directly from contempora-neous mystery plays in which actors portraying prophets frequently delivered commentaries on events in Christ’s life. large sculptured shrine (fig. 20-3) by Jacques de Baerze (active ca. 1384–1399) and a pair of painted exterior panels (fig. 20-4) by Melchior Broederlam (active ca. 1387–1409). Altarpieces were a major art form north of the Alps during the late 14th and the 15th century. From their position behind the altar, they served as backdrops for the Mass, the ritual celebration of the Holy Eucharist. At the Last Supper, Christ commanded his apostles to reenact the Eucharistic meal and repeat in memory of him the communion credo, wherein he tenders his body to eat and his blood to drink (see “The Life of Jesus in Art,” pages 244–245). This act serves as the nucleus of the Mass, which involves this reenactment as well as prayer and contemplation of the word of God. Because the Mass involves not only a memorial rite but Christian doctrine as well, art has traditionally played an important role in giving visual form to complex theological concepts for the faithful. Like the narrative reliefs in medieval church portals, these altarpieces had an important teaching function, especially for the illiterate. By reinforcing Church doctrines visually, they also stimulated devotion. These altarpieces most often took the form of polyptychs—hinged multipaneled paintings or multiple carved relief panels. The hinges enabled the clergy to close the polyptych’s side wings over the central panel(s). Because artists decorated both the exterior and inte-rior of the altarpieces, this multi-image format provided the opportu-nity to construct narratives through a sequence of images. Although concrete information is lacking about when the clergy opened and closed the altarpieces, the wings probably normally remained closed but were opened on Sundays and feast days. On this schedule, view-ers could have seen both the interior and exterior—diverse imagery at various times according to the liturgical calendar. Given their placement in churches as backdrops to the Mass, it is not surprising that among the many kinds of scenes depicted on altarpieces, themes directly related to Christ’s sacrifice are com-mon. The Champmol altarpiece, or retable, for example, features sculpted passion scenes on the interior: the Crucifixion (at the cen-ter) and (at left and right respectively) the adoration of the magi and the entombment of Christ, with rows of saints on the wings, all framed by delicate pinnacles, tracery, and lancets. The carved wood narratives span the full life cycle of Jesus from his birth to his death and burial, with the figure of the Savior on the cross forming a fit-ting backdrop to the Eucharist. On the Champmol retable’s painted wings (fig. 20-4), Broeder-lam depicted the Annunciation and Visitation (on the left panel) and the presentation in the temple and flight into Egypt (on the right). Thus Broederlam’s painted images on the altarpiece’s exterior gave a fuller account of the Savior’s early life and set the stage for de Baerze’s passion scenes when the wings were folded back to reveal the sculpted narratives. The two painted wings include both landscape and inte-rior scenes. Broederlam depicted the buildings in both Romanesque and Gothic styles. Scholars have suggested that the juxtaposition of different architectural styles in the left panel is symbolic. The rotunda (round building, usually with a dome, a common antique type) refers to the Old Testament, whereas the “modern” Gothic porch with its lancet windows and tracery relates to the New Testament. In the right panel, a statue of a Greco-Roman god falls from the top of a column as the holy family approaches. These and other details announce the coming of the new order under Christ. Stylistically, Broederlam’s panels are a mixture of three-dimen-sional rendition of the landscape and buildings with a solid gold background and flat gold haloes for the holy figures, regardless of the positions of their heads. Despite these lingering medieval pictorial conventions, the altarpiece is an early example of many of the artistic developments that preoccupied European artists throughout the 15th century, especially the illusionistic depiction of three-dimensional objects and the naturalistic representation of landscape. Oil Painting. The Retable de Champmol also foreshadowed an-other significant development in 15th-century art: the widespread adoption of oil paints, which Broederlam mixed with tempera in this early example (see “Tempera and Oil Painting,” page 574). Oil paints facilitated the exactitude in rendering details so charac-teristic of Northern European painting. Although the Italian biogra-pher Giorgio Vasari (see “Giorgio Vasari’s Lives,” page 648) and other 16th-century commentators credited the Flemish master Jan van Eyck (discussed later in this chapter) with the invention of oil paint-ing, recent evidence has revealed that oil paints had been known for some time, well before Melchior Broederlam liberally used oils for Philip the Bold’s Dijon altarpiece. Flemish painters built up their pic-tures by superimposing translucent paint layers on a layer of under-painting, which in turn had been built up from a carefully planned drawing (compare Saint Luke at work in fig. 20-1) made on a panel prepared with a white ground. With the oil medium, artists could create richer colors and more subtle gradations of tone than previ-ously possible, giving their paintings the illusion of glowing light and glistening surfaces. These traits differed significantly from the high-keyed color, sharp light, and rather matte (dull) surface of tempera. The brilliant and versatile oil medium suited perfectly the formal intentions of the generation of Flemish painters after Broederlam, who aimed for sharply focused clarity of detail in their representation of objects ranging in scale from large to almost invisible. Manuscript painting During the 15th century, Northern European artists built on the achievements of Gothic painters (see “Gothic Book Production,” page 402) and produced exquisitely refined illuminated manu-scripts. Among the most significant developments in manuscript painting was a new interest in representing fully modeled figures moving freely in convincing three-dimensional settings. Increased contact with Italy, where Renaissance artists had revived the picto-rial principles of classical antiquity, may have influenced Northern painters’ interest in illusionism. Limbourg Brothers. The most innovative early-15th-century manuscript illuminators were the three Limbourg brothers—Pol, Herman, and Jean—from Nijmegen in the Netherlands. They were nephews of Jean Malouel, the court artist of Philip the Bold, who painted Sluter’s Well of Moses statues (fig. 20-2). Following in the footsteps of earlier illustrators such as Jean Pucelle (figs. 13-36 and 13-36A), the Limbourg brothers expanded the illusionistic capabili-ties of illumination. Trained in the Netherlands, the brothers moved to Paris no later than 1402, and between 1405 and their death in 1416 (probably from the plague), they worked in Paris and Bourges for Jean, duke of Berry (r. 1360–1416) and brother of Philip the Bold of Burgundy and King Charles V (r. 1364–1380) of France. Jean ruled the western French regions of Berry, Poitou, and Auvergne (map 20-1). The duke was an avid art patron and focused on collecting manuscripts, jewels, and rare artifacts. Among the more than 300 manuscripts he owned were Pucelle’s Belleville Breviary (fig. 13-36) and the Hours ofJeanne d’Evreux (fig. 13-36A) as well as Les Très Riches Heures du Duc de Berry (The Very Sumptuous Hours of the Duke of Berry; figs. 20-5 and 20-6), which he commissioned the Limbourg brothers to produce. A Book of Hours, like a breviary, was The French Ducal Courts Limbourg brothers (Pol, Herman, Jean), January, from Les Très Riches Heures du Duc de Berry, 1413–1416. Colors and ink on vellum, 8 7 80 × 5 3 80. Musée Condé, Chantilly. The pictures in Les Très Riches Heures depict characteristic activities of each month. The prominence of genre subjects reflects the increasing inte-gration of religious and secular art in the 15th century. a book used for reciting prayers (see “Medieval Books,” page 324). As prayer books, they replaced the traditional psalters (books of psalms), which were the only liturgical books in private hands until the mid-13th century. Books of Hours contained liturgical passages to be read privately at set times during the day, from matins (dawn prayers) to compline (the last of the prayers recited daily), including the “Office [prayer] of the Blessed Virgin.” An illustrated calendar containing local religious feast days usually preceded the Office of the Blessed Virgin. Penitential psalms, devotional prayers, litanies to the saints, and other prayers, including those of the Holy Cross and for the dead, followed. Books of Hours became favorite possessions of the Northern European aristocracy during the 14th and 15th centuries. These costly books eventually became available to affluent merchants and contributed to the decentralization of religious practice that was one factor in the Protestant Reformation in the early 16th century (see “Luther and the Reformation,” page 692). The full-page calendar pictures of Les Très Riches Heures are the most famous in the history of manuscript illumination. They 20-6 Limbourg brothers (Pol, Herman, Jean), October, from Les Très Riches Heures du Duc de Berry, 1413–1416. Colors and ink on vellum, 8 7 80 × 5 3 80. Musée Condé, Chantilly. The Limbourg brothers were pioneers in expanding the illusionistic capabili-ties of manuscript painting with their care in rendering architectural details and their convincing depiction of cast shadows. represent the 12 months in terms of the associated seasonal tasks, alternating scenes of nobility and peasantry, and featuring the duke’s relationship with his courtiers and peasants. Above each picture is a lunette in which the Limbourgs depicted the zodiac signs and the chariot of the sun as it makes its yearly cycle through the heavens. Beyond its function as a religious book, Les Très Riches Heures also furnishes a picture of life in the territory the duke ruled—a picture designed to flatter the Limbourgs’ patron. For example, the color-ful calendar picture for January (fig. 20-5) portrays a New Year’s reception at court. The duke appears as magnanimous host, his head circled by the fire screen, almost halolike, behind him. His chamberlain stands next to him, urging the guests forward with the words “aproche, aproche,” words that call attention to the Lim-bourgs’ success in creating the illusion of deep spatial recession. The lavish spread of food on the table and the large tapestry on the back wall augment the richness of the setting and the occasion By contrast, the illustration for October (fig. 20-6) focuses on the peasantry. Here, the Limbourg brothers depicted a sower, a man plowing on horseback, and washerwomen, along with city dwell-ers, who promenade in front of the Louvre, the French king’s resi-dence at the time, now one of the world’s great art museums. (Paris was not then the highly populated urban center it is today. Open fields surrounded the royal palace.) The peasants do not appear dis-contented as they go about their various tasks. Surely this imagery flattered the duke’s sense of himself as a compassionate master. The growing artistic interest in naturalism is evident here in the careful way the painter recorded the architectural details of the Louvre and in the convincing shadows of the people and objects (such as the archer scarecrow and the horse) in the scene. As a whole, Les Très Riches Heures reinforced the image of the duke of Berry as a devout man, cultured bibliophile (“lover of books”), sophisticated art patron, and powerful and magnanimous leader. Further, the expanded range of subject matter, especially the prominence of genre subjects in a religious book, reflected the increasing integration of religious and secular concerns in both art and life during the 15th century. Although all three Limbourg brothers worked on Les Très Riches Heures, art historians have never been able to ascertain definitively which brother painted which images. (One scholar has suggested that because the book was left unfinished at the time of the brothers’ deaths, some of the details are the work of a fourth artist, who completed the illustrations around the middle of the century.) Given the common practice of collaboration on artistic projects at this time, however, the determination of specific author-ship is not very important. Together, the Très Riches Heures illumi-nators reoriented the art of manuscript illumination to approximate more closely the art of panel painting, treating the pages of books as if they were windows onto the world of 15th-century Europe. Mary of Burgundy. The Limbourgs’ most accomplished suc-cessor at the end of the century was an anonymous illuminator known as the Master of Mary of Burgundy. Some scholars identify him as Alexander Bening (ca. 1444–1519) of Ghent, a painter in the circle of Hugo van der Goes (fig. 20-16). The two facing pages illustrated here (fig. 20-7) are the opening full-page illumination and one of the daily prayers in the private devotional Book of Hours that belonged to Mary, the last duchess of Burgundy (r. 1477–1482) and daughter of Charles the Bold. She is the elegantly dressed woman sitting in a private chapel with her pet dog on her lap, reading from a prayer book of the same size and format as the one in which her portrait appears. On a ledge to her left are her rosary beads and a tall vase with purple irises—flowers associated tempera and oil painting The generic words paint and pigment encompass a wide range of substances that artists have used through the ages. Fresco aside (see “Fresco Painting,” page 428), during the 14th century, egg tempera was the material of choice for most painters, both in Italy and northern Europe. Tempera consists of egg combined with a wet paste of ground pigment. In his influential 1437 guidebook Il libro dell’arte (The Handbook of Art; see “Imitation and Emulation in Renaissance Art,” page 606), Cennino Cennini (ca. 1370–ca. 1440) noted that artists mixed only the egg yolk with the ground pigment, but analyses of paintings from this period have revealed that some artists chose to use the entire egg. Images painted with tempera have a velvety sheen. Artists usually applied tempera to the painting surface with a light touch because thick application of the pig-ment mixture would result in premature cracking and flaking. Some artists used oil paints (powdered pigments mixed with lin-seed oil) as far back as the eighth century, but not until the early 1400s did oil painting become widespread. Melchior Broederlam (fig. 20-4), Robert Campin (fig. 20-8), and other Flemish artists were among the first to employ oils extensively, often mixing them with tempera, as Broederlam did. (Italian painters soon followed suit, underscoring that artistic exchanges across the Alps went in both directions during the Renaissance.) The discovery of better drying components in the early 15th century enhanced the setting capabilities of oils. Rather than apply these oils in the light, flecked brushstrokes that the tempera technique encouraged, artists laid down the oils in transparent layers, or glazes, over opaque or semiopaque underlayers. In this manner, painters could build up deep and subtly gradated tones through repeated glazing. Unlike works in tempera, whose surface dries quickly due to water evaporation, oils dry more uniformly and slowly, giving the artist time to rework areas. This flexibility must have been particularly appealing to artists who worked very deliberately, such as Campin, Jan van Eyck, Rogier van der Wey-den, and the other Flemish masters discussed in this chapter, as well as the Italian Leonardo da Vinci (figS. 22-2 and 22-5). Leonardo also preferred oil paint because its gradual drying process and consistency enabled him to blend the pigments, thereby creating the impressive sfu-mato (smoky) effect that contributed to his fame. Moreover, while dry-ing, oil paints smooth out, erasing any trace of the brush that applied the paint. Oil paints also produce a glowing surface, creating a rich visual effect unlike the duller sheen of tempera. Both tempera and oils can be applied to various surfaces. Through the early 16th century, wood panels served as the foundation for most paintings. Italians painted on poplar. Northern European artists used oak, lime, beech, chestnut, cherry, pine, and silver fir. Local availability of these timbers determined the choice of wood. Linen canvas became increasingly popular in the late 16th century. Although evidence sug-gests that artists did not intend permanency for their early images on canvas, the material proved particularly useful in areas such as Venice where high humidity warped wood panels and made fresco unfeasible. Furthermore, until artists began to use wood bars to stretch the can-vas to form a taut surface, canvas paintings could be rolled and were lighter and more compact and therefore more easily portable than wood panels. with the Virgin Mary. The masterful representation of rich fabrics, Mary’s transparent veil, and the still life of flowers all attest to this painter’s skill and powers of observation. Even more remarkable is the illuminator’s meticulously detailed depiction of the Gothic church seen through the window of Mary’s chapel, especially because the manuscript page is only half the size of Jan van Eyck’s Madonna in a Church (fig. 20-10A). The scene presented to the viewer through the chapel window within the page’s “window onto the world”—a brilliant conception in itself—is the realization of Mary’s prayers. The duchess has been granted a private audience with the Virgin without any interced-ing priest. She, accompanied by her ladies-in-waiting, kneels before the Virgin, who sits in front of the church altar, attended by angels and holding the Christ Child in her lap. Both holy figures turn their heads to look at the duchess. The illumination has few peers in the history of art as an image of pious devotion. FLANDERS As noted, the greatest single source of income for the Burgundian ducal court came from banking and trade activities in Flanders, ter-ritory that Philip the Bold acquired when he married the Flemish count’s daughter. Flanders was also the leading artistic center of Northern Europe in the 15th century. Master of Flémalle One of the greatest Flemish painters of the generation after Melchior Broederlam was the man known as the Master of Flémalle, whom most art historians identify as Robert Campin (ca. 1375–1444), the leading painter of Tournai, who also worked in the newly popular medium of oil painting (see “Tempera and Oil Painting,” page 574). His most famous work is the Mérode Triptych (fig. 20-8), although it has recently been suggested that the triptych (three-panel painting) is the work of more than one artist and that the wings are a later addition. The question of authorship apart, the painting is one of the many small works of this period produced for private patrons and intended for household prayer. Perhaps the most striking feature of these private devotional images is the integration of religious and secular concerns. For example, artists often presented biblical scenes as taking place in a house (compare fig. 20-1). Religion was such an integral part of Flemish life that separating the sacred from the secular was almost impossible—and undesirable. Furthermore, the presentation in religious art of famil-iar settings and objects no doubt strengthened the direct bond that the patron or viewer felt with biblical figures. The Annunciation, prophesied in Isaiah 7:14, is the subject of the central panel of Campin’s triptych. Unseen by the Virgin, a tiny figure of Christ carrying the cross of his martyrdom and of human salvation enters the room on a ray of light, a potent symbol of the Incarnation and a foreshadowing of what lies ahead for the future Mother of God and her son. The archangel Gabriel approaches Mary, who sits reading inside a well-kept Flemish home. Through the window in the background of the right wing, the viewer sees a local cityscape, as in Rogier van der Weyden’s later Saint Luke (fig. 20-1). The depicted accessories, furniture, and utensils con-firm the locale as Flanders. However, the objects represented are not merely decorative. They also function as religious symbols. The book, extinguished candle, and lilies on the table; the copper basin in the corner niche; the towels, fire screen, and bench all symbolize, in different ways, the Virgin’s purity and her divine mission. In the right panel, Joseph, apparently unaware of the angel’s arrival, has constructed two mousetraps, symbolic of the theologi-cal concept that Christ is bait set in the trap of the world to catch the Devil. The ax, saw, and rod that Campin painted in the fore-ground of Joseph’s workshop not only are tools of the carpenter’s trade but also are mentioned in Isaiah 10:15. In the left panel, the closed garden is symbolic of Mary’s purity, and the flowers Campin included relate to Mary’s virtues, especially humility. The triptych’s donor, Peter Inghelbrecht, a wealthy merchant, and his wife, Margarete Scrynmakers, kneel in the garden and witness the momentous event through an open door. Donor portraits—portraits of the individual(s) who commissioned (or “donated”) the work—became very popular in the 15th century. In this instance, in addi-tion to asking to be represented in their altarpiece, the Inghelbrechts probably specified the subject. Inghelbrecht means “angel bringer,” a reference to Gabriel’s bringing the news of Christ’s birth to Mary in the central panel. Scrynmakers means “cabinet-or shrine-makers,” and probably inspired the workshop scene in the right panel. Jan van eyck In 1425, Jan van Eyck (ca. 1395–1441), the most famous of several internationally renowned Flemish artists, became the court painter of Philip the Good, duke of Burgundy (r. 1419–1467). In 1431, he moved his studio to Bruges, where the duke maintained his official residence. Ghent Altarpiece. The year Jan arrived in Bruges, he set out to complete the Ghent Altarpiece (figs. 20-9 and 20-10), which, according to the dedicatory inscription, his older brother, Hubert van Eyck (ca. 1385–1426), had begun. Given Jan’s stature today, it is noteworthy that the inscription describes Hubert as an artist “than whom there was no greater” and Jan as “his brother, second in art.” The nearly 12-foot-tall Ghent retable is one of the largest of the 15th century. Jodocus Vyd (d. 1439), diplomat-retainer of Philip the Good, and his wife, Elisabeth Borluut (d. 1443), commissioned the polyptych as the centerpiece of the chapel Vyd built in the Ghent church originally dedicated to Saint John the Baptist (since 1540, Saint Bavo Cathedral). Vyd’s largesse and the political and social connections that the Ghent Altarpiece revealed to its audience contributed to Vyd’s appointment as the city’s burgomeister (chief magistrate; mayor) shortly after the unveiling of the work. Two of the exterior panels (fig. 20-9) depict the donors. The husband and wife, in paired niches with Gothic tracery, kneel with their hands clasped in prayer. They gaze piously at two illusionistically rendered statues (painted in grisaille—that is, solely in gray tones to imitate stone) that reflect the innovative style of Claus Sluter (figs. 20-2 and 20-2A). The sculptures represent Ghent’s patron saint, John the Baptist, and John the Evangelist, who was probably Vyd’s patron saint. The Annunciation appears on the upper register, with a care-ful representation of a Flemish town outside the painted window of the center panel (compare figs. 20-1 and 20-8). In the uppermost arched panels, Jan depicted the Old Testament prophets Zachariah and Micah, along with sibyls, Greco-Roman mythological female prophets whose writings the Church interpreted as prophecies of Christ. An interesting detail is the exchange of words between Gabriel and the Virgin. Jan painted the words of Mary’s response upside down, because they are directed to God in Heaven. When open (fig. 20-10), the altarpiece reveals a richly colored painting of human redemption through Christ. In the upper regis-ter, God the Father—wearing the pope’s triple tiara, with a worldly Flanders 575 Copyright 20-9 Hubert and Jan van Eyck, Ghent Altar-piece (closed), Saint Bavo Cathedral, Ghent, Belgium, ca. 1423–1432. Oil on wood, 119 50 × 79 60. Grandiose multipanel painted altarpieces were popular in Flemish churches. Artists decorated both the interiors and exteriors of these polyp-tychs, which often, as here, included donor portraits. 1 ft. 1 ft. 20-10 Hubert and Jan van Eyck, Ghent Altarpiece (open), Saint Bavo Cathedral, Ghent, Belgium, ca. 1423–1432. Oil on wood, 119 50 × 159 10. In this richly colored painting of salvation from the Original Sin of Adam and Eve, God the Father presides in majesty. The van Eyck brothers used oil paints to render every detail with loving fidelity to appearance. 576 crown at his feet and resplendent in a deep-scarlet mantle—presides in majesty. To God’s right is the Virgin, represented, as in the Gothic age and in a small Jan van Eyck diptych (two-paneled painting; fig. 20-10A), as the queen of Heaven, with a crown of 12 stars on her head. John the Baptist sits to God’s left. To either side is a choir of angels, with an angel playing an organ on the right. Adam and Eve appear in the far panels. The inscriptions in the arches above Mary and Saint John extol the Virgin’s virtue and purity and Saint John’s greatness as the forerunner of Christ (see “Early Christian Saints,” pages 246–247). The inscription above the Lord’s head translates as “This is God, all-powerful in his divine majesty; of all the best, by the gentle-ness of his goodness; the most liberal giver, because of his infinite a second opinion Giovanni Arnolfini and His Wife In 1434, Jan van Eyck depicted Giovanni Arnolfini, a Lucca financier who had established himself in Bruges as an agent of the Medici family, and his second wife in their home (fig. 20-11). Arnolfini holds the hand of his spouse, whose name is not known. That much is certain, but the purpose and meaning of the double portrait remain the subject of con-siderable debate, with a few new interpretations having been advanced just during the last several years. According to the traditional interpreta-tion of the painting, Jan recorded the couple taking their marriage vows. As in the Mérode Triptych (fig. 20-8), almost every object portrayed car-ries meaning. For example, the little dog symbolizes fidelity (the com-mon canine name Fido originated from the Latin fidere, “to trust”). The finial (crowning ornament) of the marriage bed at the right is a tiny statue of Saint Margaret, patron saint of childbirth. (The bride is not yet preg-nant, although the fashionable costume she wears makes her appear so.) From the finial hangs a whiskbroom, symbolic of domestic care. Indeed, even the placement of the two figures in the room is meaningful. The woman stands near the bed and well into the room, whereas the man stands near the open window, symbolic of the outside world. Many art historians, however, dispute this interpretation because, among other things, the room in which Arnolfini and his wife stand is a public reception area, not a bedchamber. One scholar has suggested that Arnolfini is conferring legal privileges on his wife to conduct busi-ness in his absence. Another thinks that this may be a memorial portrait of a wife who died in childbirth. In any case, an important aspect of the painting is that the artist functions as a witness to whatever event is taking place. In the back-ground, framed by the arms and joined hands of the two figures, is a convex mirror (complete with its spatial distortion, brilliantly recorded; compare fig. 22-40), in which Jan depicted not only the principals, Arnolfini and his wife, but also two persons who look into the room through the door. (Arnolfini’s raised right hand may be a gesture of greeting to the two men.) One of these must be the artist himself, as the elegant inscription above the mirror, Johannes de Eyck fuit hic (“Jan van Eyck was here”), announces that he was present. The self-portrait also underscores the painter’s self-consciousness as a professional art-ist whose role deserves to be recorded and remembered. generosity.” The step behind the crown at the Lord’s feet bears the inscription “On his head, life without death. On his brow, youth without age. On his right, joy without sadness. On his left, security without fear.” The entire altarpiece amplifies the central theme of salvation. Even though humans, personified by Adam and Eve, are sinful, they will be saved because God, in his infinite love, will sac-rifice his own son for their sake. The panels of the lower register extend the symbolism of the upper. In the center panel, saints arrive from the four corners of the earth through an opulent, flower-spangled landscape. They pro-ceed toward the altar of the Lamb and the octagonal fountain of life (compare fig. 20-2). The book of Revelation passage that recounts the adoration of the Lamb is the main reading on All Saints’ Day (November 1). The Lamb symbolizes the sacrificed son of God, whose heart bleeds into a chalice, while into the fountain spills the “pure river of water of life, clear as crystal, proceeding out of the throne of God and of the Lamb” (Rev. 22:1). On the right, the 1 ft. 20-11 Jan van Eyck, Giovanni Arnolfini and His Wife, 1434. Oil on wood, 29 90 × 19 10 1 20. National Gallery, London. Jan van Eyck played a major role in establishing portraiture as an important Flemish art form. In this portrait of an Italian financier and his wife, he also portrayed himself in the convex mirror on the rear wall. Flanders Framed paintings Until the mid-20th century, when painters began to affix canvas to simple wood stretcher bars to provide a taut painting surface devoid of orna-mentation, artists considered the frame an integral part of the painting. Frames served a number of functions, some visual, others conceptual. For paintings such as large-scale altarpieces that were part of a larger environment, frames often served to integrate the painting with its sur-roundings. Frames could also be used to reinforce the illusionistic nature of the painted image. For example, the Italian painter Giovanni Bellini, in his San Zaccaria Altarpiece (fig. 22-29), duplicated the carved pilasters of the architectural frame in the painting itself, thereby enhancing the illusion of space and giving the painted figures an enhanced physical presence. In the Ghent Altarpiece, the frame seems to cast shadows on the floor between the angel and Mary in the Annunciation scene (fig. 20-9, top). More commonly, artists used frames specifically to dis-tance the viewer from the (often otherworldly) scene by calling attention to the separation of the image from the viewer’s space. Most 15th-and 16th-century paintings included elaborate frames that the artists themselves helped design and construct. Extant con-tracts reveal that the frame could account for as much as half of the cost of an altarpiece. Frequently, the commissions called for painted or gilded frames, adding to the expense. For small works, artists some-times affixed the frames to the panels before painting, so that the frame was a point of reference as they worked. Occasionally, a single piece of wood served as both panel and frame, and the artist (or, in practice, an assistant) carved the painting surface from the wood, leaving the edges as a frame. Larger images with elaborate frames, such as altarpieces, required the services of a professional woodcarver or stonemason. The painter worked closely with the individual constructing the frame to ensure its appropriateness for the image(s) produced. Unfortunately, over time, many frames have been removed from their paintings. For instance, in 1566 church officials dismantled the Ghent Altarpiece and detached its elaborately carved frame in order to protect the sacred work from Protestant iconoclasts (see “Art and the Reformation,” page 692). As ill luck would have it, when the panels were reinstalled in 1587, no one could find the frame. Sadly, the absence of many of the original frames of old paintings deprives viewers today of the painter’s complete artistic vision. Conversely, when the original frames exist, they sometimes provide essential information, such as the 1 in. 20-12 Jan van Eyck, Man in a Red Turban, 1433. Oil on wood, 19 11 80 × 10 1 40. National Gallery, London. Man in a Red Turban is the first known Western painted portrait in a thousand years in which the sitter looks directly at the viewer. The inscribed frame suggests that it is a self-portrait of Jan van Eyck. subject, name of the painter, and date. For example, the inscriptions on the frame of Jan van Eyck’s Man in a Red Turban (fig. 20-12) state that he painted it on October 21, 1433, and the inclusion of “As I can” and omission of the sitter’s name suggest that the painting is a self-portrait. 12 apostles and a group of martyrs in red robes advance. On the left appear prophets. In the right background come the virgin martyrs, and in the left background the holy confessors approach. On the lower wings, hermits, pilgrims, knights, and judges enter from left and right. They symbolize the four cardinal virtues: Temperance, Prudence, Fortitude, and Justice, respectively. The altarpiece cele-brates the whole Christian cycle from the fall of man to the redemp-tion, presenting the Church triumphant in heavenly Jerusalem. Jan used oil paints to render the entire altarpiece in shim-mering colors that defy reproduction. No small detail escaped the painter. With pristine specificity, he revealed the beauty of the most insignificant object. He depicted the soft texture of hair, the glitter of gold in the heavy brocades, the luster of pearls, and the flash-ing of gems, all with loving fidelity to appearance. This kind of meticulous attention to recording details became a hallmark of Flemish panel painting in the 15th century. Giovanni Arnolfini. Emerging capitalism led to prosperity in Europe’s booming urban centers and fueled in turn the growing bourgeois market for art objects, particularly in Bruges, Antwerp, and, later, Amsterdam. The increased wealth of the merchant class contributed to an expanded market for secular art in addition to religious artworks. It is noteworthy, for example, that both the Mérode Triptych and the Ghent Altarpiece—certainly to be catego-rized as “religious art”—include painted portraits of their donors. These paintings marked a significant revival of portraiture, a genre that had languished since antiquity. Private commissions for por-traits as independent artworks began to multiply as both artists and 578 patrons became interested in the reality (both physical and psycho-logical) that portraits could reveal. In the 15th century, Flemish patrons eagerly embraced the opportunity to have their likenesses painted. The elite wanted to memorialize themselves in their dynastic lines and to establish their identities, ranks, and stations with images far more concrete than heraldic coats of arms. Portraits also served to represent state offi-cials at events they could not attend. Royalty, nobility, and the very rich would sometimes send artists to paint the likeness of a pro-spective bride or groom. For example, when young King Charles VI (r. 1380–1422) of France sought a bride, he dispatched a painter to three different royal courts to make portraits of the candidates. But prosperous merchants also commissioned portraits for their homes. An early example of secular portraiture is Jan van Eyck’s dif-ficult-to-interpret depiction of the banker Giovanni Arnolfini (see “Giovanni Arnolfini and His Wife,” page 577). Man in a Red Turban. Whatever the intended meaning of Giovanni Arnolfini and His Wife, the painting is representative of the growing importance of secular portraiture as an income-producing artistic genre in 15th-century Flanders. In Man in a Red Turban (fig. 20-12), the man whom Jan van Eyck portrayed looks directly at the viewer. This is the first known Western painted portrait in a thousand years where the sitter does so. The level, composed gaze, directed from a true three-quarter head pose, must have impressed observers deeply. The painter created the illu-sion that from whatever angle a viewer observes the face, the eyes return that gaze. Jan, with his considerable observational skill and controlled painting style, injected a heightened sense of specificity into this portrait by including beard stubble, veins in the bloodshot left eye, and weathered, aged skin. Although a definitive identifica-tion of the sitter has yet to be made, most art historians consider Man in a Red Turban a self-portrait, which Jan painted by looking at his image in a mirror (as he depicted himself in the mirror in the Arnolfinis’ home; fig. 20-11). The inscriptions on the frame (see “Framed Paintings,” page 578) reinforce this identification. Across the top, Jan wrote “As I can” in Flemish using Greek letters. One suggestion is that this portrait was a demonstration piece intended for prospective clients, who could compare the painting with the painter and judge what he “could do” in terms of recording a faith-ful likeness. Across the bottom appear the date and a statement in Latin: “Jan van Eyck made me.” The use of both Greek and Latin suggests that the artist viewed himself as both a learned man and a worthy successor to the fabled painters of antiquity. rogier van der Weyden When Jan van Eyck began work on the Ghent Altarpiece, Rogier van der Weyden (fig. 20-1) was an assistant in the work-shop of Robert Campin (fig. 20-8), but the younger Tournai painter’s fame soon eclipsed Campin’s and eventually rivaled Jan’s. Rogier’s renown rested on his skill in recording indi-vidual features and character in his portraits (fig. 20-12a) and especially on the dynamic compositions of his narrative works, which stress human action and drama. He concen-trated on Christian themes, especially those episodes in the life of Jesus that elicited pow-erful emotions—for example, the Crucifixion and Pietà (the Vir-gin Mary cradling the dead body of her son)—moving observers deeply by vividly portraying the sufferings of Christ. 20-12a Van der Weyden, Portrait of a Lady, ca. 1460. Deposition. One of Rogier’s early masterworks is Deposition (fig. 20-13), the center panel of a triptych commissioned by the archers’ guild of Louvain for the church of Notre-Dame hors-les-murs (Church of Our Lady—the Virgin—outside the [town] walls). Rogier acknowledged the patrons of this large painting by incorpo-rating the crossbow (the guild’s symbol) into the decorative trac-ery in the corners. Instead of creating a deep landscape setting, as Jan van Eyck might have, Rogier compressed the figures and action onto a shallow stage with a golden back wall, imitat-ing the large sculptured shrines so popular in the 15th century, of which Jacques de Baerze’s Retable de Champ-mol (fig. 20-3) is one of many Nether-landish examples (compare figs. 20-21 and 20-22). The device admirably served his purpose of expressing max-imum action within a limited space 20-13 Rogier van der Weyden, Deposition, center panel of a triptych from Notre-Dame hors-les-murs, Louvain, Belgium, ca. 1435–1442. Oil on wood, 79 2 5 del Prado, Madrid. 80 × 89 7 1 1 ft. 80. Museo Deposition resembles a relief carving in which the biblical figures act out a drama of passionate sorrow as if on a shallow theatrical stage. The painting makes an unforgettable emotional impression. and dramatically confronting the viewer, but the setting of the Cru-cifixion in a box is unrealistic, as is the size of the cross, the arms of which are not wide enough for Jesus’s hands to have been nailed to them. The painting, with the artist’s crisp drawing and precise mod-eling of forms, resembles a stratified relief carving, and the viewer may wonder if this is a painting of the biblical event or a painting of a shrine representing the event. In any case, a series of lateral undu-lating movements gives the group a compositional unity, a formal cohesion that Rogier strengthened by depicting the sorrowful anguish that many of the figures share. Present are the Virgin, sev-eral of her half-sisters, Joseph of Arimathea, Nicodemus, Saint John the Evangelist, and Mary Magdalene. The similar poses of Christ and his mother further unify the composition, evoke the shape of the crossbows in the corner tracery, and reflect the belief that Mary suffered the same pain at the Crucifixion as her son. ART AND SOCIETY the artist’s profession in Flanders As they did in Italy (see “Artistic Training,” page 434), guilds controlled artistic production in Flanders. To pursue a craft, individuals had to belong to the guild representing that craft. Painters, for example, sought admission to the Guild of Saint Luke, the patron saint of painters because Luke made a portrait of the Virgin Mary (fig. 20-1). The patron saint of the metalworkers’ guild was Saint Eligius (fig. 20-14), who was a goldsmith before devoting himself to the Church and eventually becom-ing bishop of Tournai. The path to eventual membership in the guild began, for men, at an early age, when the father apprenticed his son in boyhood to a mas-ter, with whom the young aspiring painter lived. The master taught the fundamentals of his craft—how to make implements, prepare panels with gesso (plaster mixed with a binding material), and mix colors, oils, and varnishes. Once the youth mastered these procedures and learned to work in the master’s traditional manner, he usually spent several years working as a journeyman in various cities, observing and absorbing ideas from other masters. He then was eligible to become a master and could apply for admission to the guild. Fees could be very high, espe-cially if an artist was not a citizen of the same city, as was the case, for example, when Petrus Christus of Baerle purchased citizenship in Bruges in order to join that city’s painters’ guild. Sometimes, an art-ist seeking admission to a guild would marry the widow of a member. (A woman could inherit her husband’s workshop, but could not run it.) Guild membership was essential for establishing an artist’s reputation and for obtaining commissions. The guild inspected paintings to evalu-ate workmanship and ensure that its members used quality materials. It also secured adequate payment for its artists’ labor. Women had far fewer opportunities than men to train as artists, in large part because of social and moral constraints that forbade women to reside as apprentices in the homes of male masters. Moreover, from the 16th century, when academic training courses supplemented and then replaced guild training, until the 20th century, women would not as a rule expect or be permitted instruction in figure painting, because it involved dissection of cadavers and study of the nude male model. Flemish women interested in pursuing art as a career—for example, Caterina van Hemessen (fig. 23-16)—most often received tutoring from fathers and husbands who were professionals and whom the women assisted in all the technical procedures of the craft. Despite these Rogier’s extraordinary ability to represent flesh and fabric rivaled Jan van Eyck’s, and few painters, not even Jan, have equaled him in rendering passionate sorrow as it vibrates through a figure or distorts a tearstained face. Rogier’s depictions of the agony of loss in Deposition and of the terror of the damned in Last Judgment (fig. 20-13a) are among the most moving and unforgettable images in religious art. It was probably Rogier whom Michelangelo had in mind when, according to the Portuguese painter Francisco de Hol-landa (1517–1584), the Italian master observed, “Flemish paint-ing [will] please the devout better than any painting of Italy, which will never cause him to shed a tear, whereas that of Flanders will cause him to shed many.”1 20-13a Van der Weyden, Last Judgment, ca. 1443–1451. 1 ft. 20-14 Petrus Christus, A Goldsmith in His Shop, 1449. Oil on wood, 39 30 × 29 100. Metropolitan Museum of Art, New York (Robert Lehman Collection, 1975). Once thought to depict Eligius, the patron saint of goldsmiths, Christus’s painting, made for the Bruges goldsmiths’ guild, is more likely a genre scene of a couple shopping for a wedding ring. obstacles, membership records of the art guilds of Bruges and other cities reveal that a substantial number of Flemish women were able to establish themselves as artists during the 15th century. That they suc-ceeded in negotiating the difficult path to acceptance as professionals is a testament to both their tenacity and their artistic skill. 580 Later Flemish painters Robert Campin, Jan van Eyck, and Rogier van der Weyden were the leading figures of the first generation of “Northern Renaissance” painters. (Art historians usually transfer to Northern Europe, with less validity than in its original usage, the term Renaissance, coined to describe the conscious revival of classical art in Italy.) The second generation of Flemish masters, active during the latter half of the 15th century, had much in common with their illustrious predeces-sors, especially a preference for using oil paints to create naturalistic representations, often, although not always, of traditional Christian subjects for installation in churches. Petrus Christus. One work of uncertain Christian content is A Goldsmith in His Shop (fig. 20-14) by Petrus Christus (ca. 1410–1472), who settled in Bruges in 1444. According to the traditional interpretation, A Goldsmith in His Shop portrays Saint Eligius (who was initially a master goldsmith before committing his life to God) sitting in his stall, showing an elegantly attired couple a selection of rings. The bride’s betrothal girdle lies on the table as a symbol of chastity, and the woman reaches for the ring the goldsmith weighs. The artist’s inclusion of a crystal container for Eucharistic wafers (on the lower shelf to the right of Saint Eligius) and the scales (a ref-erence to the Last Judgment) supports a religious interpretation of this painting and continues the Flemish tradition of imbuing every-day objects with symbolic significance. A halo once encircled the goldsmith’s head, seemingly confirming the religious nature of this scene. Scientists have determined, however, that the halo was a later addition by another artist, and restorers have removed it. Most scholars now think that the painting, although not devoid of religious content, should be seen as a vocational painting of the type often produced for installation in Flemish guild chapels. Although the couple’s presence suggests a marriage portrait, the patrons were probably not the couple portrayed but rather the goldsmiths’ guild in Bruges. Saint Eligius was the patron saint of gold-and silver-smiths, blacksmiths, and metalworkers, all of whom shared a chapel in a building adjacent to their meetinghouse. The reconsecration of this chapel took place in 1449, the same date as the Christus paint-ing. Therefore, it seems probable that the artist painted A Goldsmith in His Shop, which illustrates an economic transaction and focuses on the goldsmith’s profession, specifically for the guild chapel. A guild chapel is also the likely original setting of Rogier van der Weyden’s Saint Luke Drawing the Virgin (fig. 20-1). As noted, in the 15th century, in addition to their primary function as “trade unions,” guilds played an increasingly important role in community life and often became major patrons of art in their cities (see “The Artist’s Profession in Flanders,” page 580). Christus went to great lengths to produce a historically cred-ible image. For example, the variety of objects depicted in the paint-ing serves as advertisement for the goldsmiths’ guild. Included are the goldsmiths’ raw materials (precious stones, beads, crystal, coral, and seed pearls) scattered among finished products (rings, buckles, and brooches). The pewter vessels on the upper shelves are dona-tion pitchers, which town leaders gave to distinguished guests. All these meticulously painted objects not only attest to the centrality and importance of goldsmiths to both the secular and sacred com-munities but also enhance the naturalism of the painting. The con-vex mirror in the foreground showing another couple and a street with houses serves to extend the painting’s space into the viewer’s space, further creating the illusion of reality, as in Jan van Eyck’s Arnolfini portrait (fig. 20-11). Dieric Bouts. In Last Supper (fig. 20-15), Dieric Bouts (ca. 1415–1475) of Haarlem chose a different means of suggesting 1 ft. 20-15 Dieric Bouts, Altarpiece of the Holy Sacrament, Saint Peter’s, Louvain, Belgium, 1464–1468. Oil on wood, center panel (Last Supper) 69 × 59. The Last Supper, the central panel of this altarpiece, is one of the earliest Northern Renaissance paintings to employ Italian linear perspective. Included are portraits of the work’s Flemish patrons. spatial recession. The painting is the central panel of the Altarpiece of the Holy Sacrament, which the Confraternity of the Holy Sacra-ment in Louvain commissioned in 1464. Four years later, Bouts became the city’s offi-cial painter and was asked to produce a series of panels—including Wrongful Beheading of the Count (fig. 20-15a) and Justice of Otto III (fig. 20-15B)—for Louvain’s town hall. Bouts’s Last Supper is one of the earliest Northern Renaissance paintings to employ linear perspective and a vanishing point to create the illusion of depth. All of the central room’s orthogonals (converging diagonal lines imagined to be behind and perpendicular to the picture plane) lead to the vanishing point in the center of the mantelpiece above Jesus’s head. The small side room, however, has its own vanishing point, and neither it nor the vanishing point of the main room falls on the horizon of the landscape (the horizon line) seen through the windows, as in Italian Renaissance paintings composed according 20-15B BoutS, Justice of Otto III, ca. 1470–1473. to the strict rules of linear perspective (see “Linear Perspective,” page 599). In Last Supper, Bouts did not depict the biblical narrative itself but instead presented Jesus in the role of a priest performing the liturgical ritual of the consecration of the Eucharistic wafer. By dividing the apostles into two asymmetrical groups with no one sitting at the middle of the near side of the table, Bouts focused attention on the Savior and the food platter and wine chalice at the table’s center. Bouts’s Last Supper contrasts strongly with other depictions of the same subject, which often represented Jesus’s prediction of Judas’s betrayal or his comforting of John. The Confraternity of the Holy Sacrament dedicated itself to the worship of the Eucharist, and the smaller panels on the altarpiece’s wings depict Old Testament prefigurations of the Eucharist—for example, at the top right, the gathering of manna in the desert and, at bottom left, Jews celebrating Passover (the occasion for Jesus’s final meal). Bouts also added four servants (two looking through the window-like opening in the rear wall and two standing) not mentioned in the New Testament account, all dressed in Flemish attire. These are portraits of the four members of the confraternity who contracted Bouts to paint the altarpiece, continuing the Flemish tradition of inserting into representations of biblical events portraits of the painting’s patrons, first noted in the Mérode Triptych (fig. 20-8), where the Inghelbrechts are also looking into the room from out-side; that is, they are not participants in but witnesses of the biblical event. Hugo van der Goes. By the mid-15th century, Flemish art had achieved renown throughout Europe. The Portinari Altarpiece (fig. 20-16), for example, is a large-scale Flemish work in a family chapel in Florence, Italy. The artist who received the commission was Hugo van der Goes (ca. 1440–1482), who joined the painters’ guild of Ghent as a master in 1467 and served as the guild’s dean from 1473 to 1475. Hugo painted the triptych in Flanders for Tom-maso Portinari, an Italian shipowner and agent in Bruges for the powerful Medici bank of Florence. The altarpiece was Portinari’s gift to the church of Sant’Egidio, and he appears on the wings with his family and their patron saints, who are much larger than the donors. The main panel, Adoration of the Shepherds, depicts a sub-ject based on the 14th-century vision of a Swedish saint in which Mary, instead of cradling her newborn son, kneels solemnly to join Joseph, the angels, and the shepherds in adoring the infant Savior, who lies on the ground and glows with divine light. In order to situate the main actors at the center of the panel, Hugo tilted the ground, a compositional device he may have derived from the tilted stage floors of 15th-century mystery plays. Three shepherds enter 1 ft. 20-16 Hugo van der Goes, Adoration of the Shepherds (Portinari Altarpiece, open), from Sant’Egidio, Florence, Italy, ca. 1473–1478. Tempera and oil on wood, center panel 89 3 1 20 × 109, each wing 89 3 1 20 × 49 7 1 20. Galleria degli Uffizi, Florence. This altarpiece is a rare instance of the awarding of a major commission in Italy to a Flemish painter. The Florentines admired Hugo’s realistic details and brilliant portrayal of human character from the right rear. Hugo represented them in attitudes of wonder, piety, and gaping curiosity. Their lined faces, work-worn hands, and uncouth dress and manner indicate that they are common folk, very different than the three magi who will soon come to adore the newborn Jesus. The architecture and a continuous Northern European land-scape unify the three panels. (The bare trees of the setting estab-lish that it is winter, the season of Christ’s birth.) Symbols surface throughout the altarpiece. Iris and columbine flowers are emblems of the sorrows of the Virgin. The angels represent the 15 joys of Mary. A sheaf of wheat stands for Bethlehem (the “house of bread” in Hebrew), a reference to the Eucharist. The harp of David, embla-zoned over the building’s portal in the middle distance (just to the right of the Virgin’s head), signifies the ancestry of Christ. To stress the meaning and significance of the illustrated event, Hugo revived medieval pictorial devices. Small scenes shown in the background of the altarpiece represent (from left to right) the journey of Mary and Joseph to Bethlehem, the annunciation to the shepherds, and the arrival of the magi. Hugo’s variation in the scale of his figures to differentiate them by their importance to the central event also reflects older traditions. Still, he put a vigorous, penetrating realism to work in a new direction, characterizing human beings according to their social level while showing their common humanity. After Portinari placed the altarpiece in his family’s chapel in the Florentine church of Sant’Egidio, it created a considerable stir among Italian artists. Although the painting may have seemed unstructured to the Italians and the employing of hierarchy of scale old fashioned, Hugo’s masterful technique and what the Floren-tines deemed incredible realism in representing drapery, flowers, animals, and, above all, human character and emotion made a deep impression on them. At least one Florentine artist, Domenico Ghir-landaio (figs. 21-26 and 21-27), paid tribute to the Flemish master by using Hugo’s most striking motif, the adoring shepherds, in one of his own Nativity paintings. Hans Memling. Hugo’s contemporary, Hans Memling (ca. 1430–1494), may have trained as a painter in Rogier van der Weyden’s studio. He became a citizen of Bruges in 1465 and received numer-ous commissions from the city’s wealthy merchants, Flemish and foreign alike. He specialized in portraits of his patrons (one of whom was Tommaso Portinari; fig. 20-18A) and images of the Madonna. Memling’s many paintings of the Virgin portray young, slight, pretty princesses, each holding a doll-like infant Jesus. The center panel of the Saint John Altarpiece is Virgin with Saints and Angels (fig. 20-17). The patrons of this altarpiece—two brothers and two sisters of the order of the Hospital of Saint John in Bru-ges—appear on the exterior side panels (not illustrated). In the main panel, two angels, one playing a musical instrument and the other holding a book, flank the Virgin. To the sides of Mary’s throne stand Saints John the Baptist on the left and John the Evangelist on the right. Seated in the foreground are Saints Catherine and Barbara. This gathering celebrates the mystic marriage of Saint Catherine of Alexandria, one of many virgin saints believed to have entered into a spiritual marriage with Christ. As one of the most revered virgins of Christ, Saint Catherine provided a model of devotion that resonated with women viewers (especially nuns). The altarpiece exudes an opu-lence that results from the rich colors, the meticulously depicted tap-estries and brocades, and the serenity of the figures. The composition 1 ft. 20-17 Hans Memling, Virgin with Saints and Angels, center panel of the Saint John Altarpiece, Hospitaal Sint Jan, Bruges, Belgium, 1479. Oil on wood, center panel 59 7 3 40 × 59 7 3 40, each wing 59 7 3 40 × 29 7 1 80. Memling specialized in images of the Madonna. His Saint John Altarpiece exudes an opulence that results from the sparkling and luminous oil colors and the realistic depiction of rich tapestries and brocades 20-18 Hans Memling, Diptych of Martin van Nieuwenhove, 1487. Oil on wood, each panel 19 5 3 Bruges. 80 × 19 10. Memlingmuseum, In this diptych, the Virgin and Child pay a visit to the home of 23-year-old Martin van Nieuwenhove. A round convex mirror reflects the three figures and unites the two halves of the diptych spatially. is balanced and serene, the color sparkling and luminous, and the execution of the highest technical quality. Memling combined portraiture and Madonna imagery again in a much less ambitious—and more typical—work (fig. 20-18) that he painted for Martin van Nieuwenhove (1464–1500). The smaller scale of the private commission and its much more intimate character underscore the different approaches that painters regu-larly took when producing artworks for different kinds of patrons and for public versus private settings. Martin van Nieuwenhove was a member of an important Bruges family that held various posts in the civic government. He himself served as burgomeister of Bruges in 1497. The painting takes the form of a diptych, with the patron portrayed on the right wing praying to the Madonna and Child on the left wing, a format invented by Rogier van der Weyden. Accord-ing to inscriptions on the frames, van Nieuwenhove commissioned the work in 1487 when he was 23 years old. He died only 13 years later, 3 years after becoming mayor. The format of the van Nieuwenhove diptych follows the pat-tern that Memling used earlier for his wedding triptych Tom-maso Portinari and Maria Baroncelli (fig. 20-18a) but with only a single (male) portrait. (The lost central section of the Portinari triptych probably closely resembled the van Nieu-wenhove Madonna and Child.) Memling’s portrayals of Mary and Jesus consistently feature a tender characterization of the young Virgin and her nude infant son. Here, however, Memling set both the Madonna and her patron in the interior of a well-appointed Flemish home featuring stained-glass windows. The window to the left of the Virgin’s head bears van Nieuwenhove’s coat of arms. The window behind the donor depicts his patron saint, Martin of Tours. These precisely recorded details identify the home as van Nieuwenhove’s (the Minnewater Bridge in Bru-ges is visible through the open window), and the Madonna and Child have honored him by coming to his private residence. Even Saint Luke had to go to the Virgin’s home to paint her portrait (fig. 20-1), but the conceit is a familiar one in Flemish painting. An early example is the Annunciation taking place in the home of Peter Inghelbrecht in Robert Campin’s Mérode Triptych (fig. 20-8). In the Memling portrait diptych, the Christ Child sits on the same ledge as the donor’s open prayer book. Also uniting the two wings of the diptych is the round con-vex mirror behind the Vir-20-18a MeMling, Tommaso Porti-nari and Maria Baroncelli, ca. 1470. gin’s right shoulder in which the viewer sees the reflection of the Virgin’s back and van Nieuwenhove as well as the rest of the room (compare figs. 20-11 and 20-14). 584 FRANCE In contrast to the prosperity and peace that Flanders enjoyed dur-ing the 15th century, in France the Hundred Years’ War crippled economic enterprise and prevented political stability. The anarchy of war and the weakness of the kings gave rise to a group of duch-ies, each with significant power and the resources to commission major artworks. The strongest and wealthiest of these has already been examined—the duchy of Burgundy, which controlled Flanders, as well as the duchy of Berry in France. The French dukes of Bour-bon and Nemours as well as members of the French royal court were also important art patrons. In addition to illustrated books, such as the Très Riches Heures du Duc de Berry (figs. 20-5 and 20-6), inde-pendent paintings were popular in France, as in Flanders, for private devotional use. The preferred medium was oil paint on wood panels. Jean Fouquet. Among the French artists whose paintings were in high demand was Jean Fouquet (ca. 1425–1478). Fouquet’s workshop was in Tours, and he received important commissions from King Charles VII (r. 1422–1461, the patron and client of Jacques Coeur; fig. 13-31) and from the duke of Nemours and other elite members of the French aristocracy. Fouquet painted a diptych (fig. 20-19) for Étienne Chevalier, who, despite his lowly birth as the son of one of Charles VII’s secretaries, rose to become royal treasurer in 1452. In the left panel of the Melun Diptych (named for its original location in Melun Cathedral), Chevalier appears with his patron saint, Saint Stephen (Étienne in French). Appropriately, Fouquet’s donor portrait of Chevalier depicts his prominent patron as devout—kneeling, with hands clasped in prayer. The represen-tation of the pious donor with his standing saint recalls Flemish art, as do the three-quarter stances and the realism of Chevalier’s portrait. The artist portrayed Saint Stephen, whose head also has a portraitlike quality, holding the stone symbolizing his martyrdom (death by stoning) atop a volume of the holy scriptures, thereby ensuring that viewers can properly identify the saint. Fouquet ren-dered the entire image in meticulous detail and included a highly ornamented architectural setting. In its original diptych form (the two panels are now in differ-ent museums), the viewer would follow the gaze of Chevalier and Saint Stephen over to the right panel, which depicts the Virgin Mary and Christ Child in a most unusual way—with marblelike flesh, sur-rounded by red and blue cherubs (chubby winged child angels). The juxtaposition of these two images enabled the patron to bear wit-ness to the sacred. The integration of sacred and secular (especially the political or personal), prevalent in other Northern Renaissance artworks, also emerges here, which complicates the reading of this diptych. Agnès Sorel (1421–1450), the mistress of Charles VII, was Fouquet’s model for the Virgin Mary, whose left breast is exposed, presumably to nurse the infant Jesus, but she does not look at her son or the viewer. (Mary as nursing mother is a not uncommon way of representing the Virgin in Northern Europe; compare fig. 20-1.) Chevalier commissioned this painting after Sorel’s death, probably by poisoning while pregnant with the king’s child. Thus, in addition to the religious interpretation of this diptych, there is surely a personal 1 ft. 1 ft. 20-19 Jean Fouquet, Melun Diptych, ca. 1452. Left wing: Étienne Chevalier and Saint Stephen. Oil on wood, 39 1 Gemäldegalerie, Staatliche Museen zu Berlin, Berlin. Right wing: Virgin and Child. Oil on wood, 39 11 Museum voor Schone Kunsten, Antwerp. 40 × 29 9 1 20 × 29 9 1 20. 20. Koninklijk Fouquet’s meticulous representation of a pious kneeling donor with a standing patron saint recalls Flemish painting, as do the three-quarter stances and the realism of the donor’s portrait head 20-20 Konrad Witz, Miraculous Draft of Fish, exterior wing of Altarpiece of Saint Peter, from the Chapel of Notre-Dame des Maccabées, Cathedral of Saint Peter, Geneva, Switzerland, 1444. Oil on wood, 49 30 × 59 10. Musée d’Art et d’Histoire, Geneva. Konrad Witz set this biblical story on Lake Geneva. The painting is one of the first 15th-century works depicting a specific locale and is noteworthy for the painter’s skill in rendering water effects. 1 ft. and political narrative here as well, made all the more complex given that Sorel gave birth to three of the king’s daughters, but never a son. HOLY ROMAN EMPIRE Because the Holy Roman Empire (whose core was Germany) did not participate in the drawn-out saga of the Hundred Years’ War, its economy remained stable and prosperous. Without a domi-nant court to commission artworks, wealthy merchants and clergy became the primary German art patrons during the 15th century. panel painting The art of the early Northern Renaissance in the Holy Roman Empire displays a pronounced stylistic diversity. Some artists fol-lowed developments in Flemish painting, and large-scale altar-pieces featuring naturalistically painted biblical themes were familiar sights in German churches. Konrad Witz. Among the most notable 15th-century German altarpieces is the Altarpiece of Saint Peter, painted by Konrad Witz (ca. 1400–1446) for the chapel of Notre-Dame des Maccabées in the Cathedral of Saint Peter in Geneva. Signed by “Magister Con-radus of Basel” and dated 1444, the altarpiece is a triptych featuring Witz’s paintings on both the exterior and interior. Miraculous Draft of Fish (fig. 20-20) appears on one of the exterior wings. The other (not illustrated) depicts the release of Saint Peter from prison. The central panel is lost. On the interior wings, Witz painted scenes of the adoration of the magi and of Saint Peter’s presentation of the donor (Bishop François de Mies) to the Virgin and Child. Miraculous Draft of Fish shows Peter, the first pope, unsuccessfully trying to emulate Christ walking on water. The choice of this episode from among oth-ers in Peter’s life (see “Early Christian Saints,” pages 246–247) may be a commentary on the part of Witz’s patron, the Geneva cardinal, on the limited power of the pope in Rome. The painting is particularly significant because of the land-scape’s prominence. Witz showed his considerable skill in the recording of water effects—the shimmering sky on the slowly mov-ing lake surface, the mirrored reflections of the figures in the boat, and the transparency of the shallow water in the foreground. He observed and represented the landscape so carefully that art histo-rians have been able to determine the exact location shown. Witz presented a view of the shores of Lake Geneva, with the town of Geneva on the right and Le Môle Mountain in the dis-tance behind Christ’s head. This painting is one of the first 15th-century works depict-ing a specific, identifiable site. The work of other leading German painters of the mid-15th century—for exam-ple, Stefan Lochner (ca. 1400–1451)—retained medieval features to a much greater degree, as is immediately evident in a comparison between Witz’s landscape and Lochner’s Madonna in the Rose Gar-den (fig. 20-20a). 586 CHAPTER 20 Late Medieval and Early Renaissance Northern Europe Copyright 2021 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. Due to electronic rights, some third party content may be suppressed from the eBook and/or eChapter(s). Editorial review has deemed that any suppressed content does not materially affect the overall learning experience. Cengage Learning reserves the right to remove additional content at any time if subsequent rights restrictions require it. 20-20a lochner, Madonna in the Rose Garden, ca. 1435–1440. sculpture As in Flanders (fig. 20-3), in the Holy Roman Empire many of the leading 15th-century artists specialized in carving large wood retables. These grandiose sculpted altarpieces reveal the lingering power of the Late Gothic style. Veit Stoss. The sculptor Veit Stoss (ca. 1447–1533) trained in the Upper Rhine region, possibly in Strasbourg, but settled in Kraków (in present-day Poland) in 1477. In that year, he began work on a monumental altarpiece for the church of Saint Mary in Kraków, paid for by the city’s citizens. In the central boxlike shrine is Death and Assumption of the Virgin (fig. 20-21), peopled by huge carved, painted, and gilded figures, some 9 feet high. On both the outer and inner faces of the wings, Stoss portrayed scenes from the lives of Christ and Mary. The altar forcefully expresses the intense piety of Gothic culture in its late phase, when artists used every figural and ornamental motif in the repertoire of Gothic art to heighten the emotion and glorify sacred events. In the center panel of the Kraków altarpiece, Christ’s disciples congregate around the Virgin, who collapses, dying. One of them supports her, while another wrings his hands in grief. Above, Mary rises to Heaven with the resurrected Christ. Stoss posed others in attitudes of woe and psychic shock, striving for realism in every minute detail. He engulfed the figures in restless, twisting, and curving swaths of drapery whose broken and writhing lines unite the whole tableau in a vision of agitated emotion. The artist’s massing of sharp, broken, and pierced forms that dart flamelike through the composition—at once unifying and animating it—recalls the design principles of Late Gothic architecture (fig. 13-28). Indeed, in the Kraków altar-piece, Stoss merged sculpture and architecture, enhancing their union with paint and gilding. The Kraków altarpiece gives modern viewers the opportunity to appreciate the polychromy that was standard in ancient and medieval sculpture in both wood and stone. Examples such as this one are unfortunately rare. The vast majority of preserved statues and reliefs from antiquity and the Middle Ages give a false impres-sion of their original appearance (compare figs. 3-13A and 5-63A) because the paint has disappeared. 10 ft. 20-21 Veit Stoss, Death and Assumption of the Virgin, center panel of the Altarpiece of the Virgin Mary (with wings open), Church of Saint Mary, Kraków, Poland, 1477–1489. Painted and gilded lime-wood, central panel 239 90 high. In this huge painted and gilded sculptured wood altarpiece, Stoss used every figural and ornamental element from the vocabulary of Gothic art to heighten the emotion and glorify the sacred event. 20-22 Tilman Riemenschneider, Assumption of the Virgin (Creglingen Altarpiece), Herrgottskirche, Creglingen, Germany, ca. 1495–1505. Lime-wood, 309 20 high. Riemenschneider specialized in carving large unpainted wood retables. His works feature intricate Gothic trac-ery and religious figures whose bodies are almost lost within their swirling garments. into fluid motion by employing an endless and restless line running through the garments of the figures. The draperies float and flow around bodies lost within them, serving not as descrip-tions but as design elements that tie the figures to one another and to the framework. A look of psychic strain, a facial expression common in Riemenschneider’s work, heightens the spiritu-ality of the figures, immaterial and weightless as they appear. Graphic arts 10 ft. A new age blossomed in the 15th century with a sudden technological advance that had wide-spread effects—the invention by Johannes Gutenberg (ca. 1400–1468) of moveable type around 1450 and the development of the print-ing press. Printing had been known in China centuries before, but had never fostered, as it did in 15th-century Europe, a revolution in written communication and in the generation and man-agement of information. Printing provided new and challenging media for artists, and the earli-est form was the woodcut. Artists produced inex-pensive woodcuts such as the Buxheim Saint Christopher (fig. 20-22a) before the development of moveable-type print-ing. But when the im-proved economy and a rise in literacy necessi-tated the production of illustrated books on a grand scale, artists met the challenge of bringing the woodcut picture onto the same letterpress text pages (see “How to Illustrate Printed Books,” page 589). 20-22a Buxheim Saint Christopher, 1423(?). Martin Schongauer. The woodcut medium hardly had matured when printmakers intro-duced the technique of engraving (see “Engrav-Tilman Riemenschneider. Assumption of the Virgin is also the center panel of the Creglingen Altarpiece (fig. 20-22), carved by Tilman Riemenschneider (ca. 1460–1531) of Würzburg for a parish church in Creglingen, Germany. Riemenschneider incor-porated intricate Gothic forms, especially in the 30-foot-tall altar-piece’s elaborate canopy, but unlike Stoss, he did not paint the figures or the background, relying instead purely on sculptural form. The Würzburg master succeeded in setting the whole design ing and Etching,” page 590). Begun in the 1430s and well developed by 1450, engraving proved much more flexible than woodcut. Predictably, in the second half of the century, engraving began to replace the woodcut process for making both book illustrations and widely popular single prints. Not surprisingly, many of the earli-est engravers were professional goldsmiths, who easily applied their training in incising designs into gold and silver jewelry to the new art form. how to illustrate printed Books With the invention of moveable type in the 15th century and the new widespread availability of paper from commercial mills, the art of print-making developed rapidly in Europe. A print is an artwork created by transferring a design on a metal plate or a wood or stone block to a sheet of paper. Prints are usually produced in multiple impressions. The set of prints that an artist creates from a single block or plate is called an edition. Like the manufacturing of books on a press, the printmaking process involves the transfer of ink from a printing surface to paper. This can be accomplished in several ways. The oldest and simplest is the relief method—carving the design into a surface, usually a soft wood, such as pear. Relief print-ing requires artists to conceptualize their images in reverse—that is, they must draw mirror images of the intended design on the wood block. They then remove the surface areas around the drawn lines using a gouging instrument. Thus when the printmaker inks the ridges that correspond to the original (reversed) drawing, the hollow areas remain dry, and a correctly oriented image results when the artist presses the printing block against paper. Because artists produce woodcuts through a subtractive process (removing parts of the mate-rial), it is difficult to create very thin, fluid, and closely spaced lines. Moreover, if the ridges are too thin, they will break during printing. As a result, woodcut prints (for example, figS. I-9, 20-22A, and 20-23) tend to exhibit stark contrasts between the dark lines and the blank background. During the later 15th century, publishers realized that the wood-cut was the ideal medium for solving the problem of illustrating their new printed books. The new technology quickly led to the demise of the manuscript illuminator as well as the scribe, both of whom had been essential for the production of illustrated books through the late Middle Ages, whether they were monks working in monastic scriptoria or lay professionals employed in the for-profit workshops of Paris and other cities. The most ambitious early effort to produce low-cost mass-produced printed books was the so-called Nuremberg Chronicle, a history of the world produced in Nuremberg by anton koBerger (ca. 1445–1513), with more than 650 illustrations furnished by the workshop of Michael WolgeMut (1434–1519). The hand-colored page illustrated here (fig. 20-23) represents Madeburga (modern Magde-burg, Germany). The blunt, simple lines of the woodcut technique give a detailed perspective of Magdeburg, its harbor and shipping, its walls and towers, its churches and municipal buildings, and a statue-topped columnar monument. Despite the numerous architectural structures, this illustration is not an accurate depiction of the city but the prod-uct of the artist’s fanciful imagination. Wolgemut often used the same image to illustrate different cities, even those with very little in common—for example, Verona, Italy, and Damascus, Syria. This depiction of Magdeburg is a generic view of a late medieval German town, not a portrait of a specific place. Regardless, the Nuremberg Chronicle is a monument to a new craft, which expanded in concert with the art of the printed book. 20-23 Michael Wolgemut and workshop, Madeburga, page from the Nurem-berg Chronicle, 1493. Woodcut, 19 6 1 80 × 29 15 80. Printed by Anton Koberger. The Nuremberg Chronicle is an early example of wood-cut illustrations in printed books. The more than 650 pictures include detailed views of towns, but they are generic rather than specific portrayals. 1 engraving and etching In contrast to the production of relief prints, in the intaglio method of printmaking, the artist incises (cuts) the lines on a metal plate, often copper, rather than cuts away the area around the lines, as the relief printer does. The image can be created on the plate manually (engrav-ing or drypoint; for example, fig. 20-24) using a tool (a burin or stylus) or chemically (etching; for example, fig. 25-16). In the etching process, an acid bath eats into the exposed parts of the plate where the artist has drawn through an acid-resistant coating. When the artist inks the surface of the intaglio plate and wipes it clean, the ink is forced into the incisions. Then the artist runs the plate and paper through a roller press, and the paper absorbs the remaining ink, creating the print. Because the artist “draws” the image onto the plate, intaglio prints differ in char-acter from relief prints, such as woodcuts. Engravings, drypoints, and etchings generally present a wider variety of linear effects, as is imme-diately evident in a comparison of the roughly contemporaneous wood-cut (fig. 20-23) by Michael Wolgemut and an engraving (fig. 20-24) by Martin Schongauer. Intaglio prints also often reveal to a greater extent evidence of the artist’s touch, the result of the hand’s changing pressure and shifting directions. The paper and inks that artists use also affect the finished look of the printed image. During the 15th and 16th centuries, European print-makers used papers produced from cotton and linen rags that paper-makers mashed with water into a pulp. The papermakers then applied a thin layer of this pulp to a wire screen and let it dry to create the paper. As contact with Asia increased, printmakers made greater use of what was called Japan paper (of mulberry fibers) and China paper. Artists, then as now, could select from a wide variety of inks. The type and pro-portion of the ink ingredients affect the consistency, color, and oiliness of inks, which various papers absorb differently. Paper is lightweight, and the portability of prints has been an important factor in their appeal to artists. The opportunity to produce numerous impressions from the same print surface also made printmak-ing attractive to 15th-and 16th-century artists. In addition, prints can be sold at much lower prices than paintings or sculptures. Consequently, prints reached a far wider audience than did one-of-a-kind artworks. The number and quality of existing 15th-and 16th-century European prints attest to the importance of the new print medium. 20-24 Martin Schongauer, Saint Anthony Tormented by Demons, ca. 1480. Engraving, 19 1 40 × 90. Fondazione Magnani Rocca, Corte di Mamiano. Schongauer was the most skilled of the early masters of metal engraving. By using a burin to incise lines in a copper plate, he was able to create a marvelous variety of tonal values and textures. 1 in. Martin Schongauer (ca. 1430–1491) of Colmar, a painter and the son of a goldsmith, was the most skilled and subtle North-ern European master of metal engraving. His Saint Anthony Tor-mented by Demons (fig. 20-24) shows both the versatility of the medium and the artist’s mastery of it. The stoic saint is caught in a revolving thornbush of spiky demons, who claw and tear at him furiously. With unsurpassed skill and subtlety, Schongauer incised lines of varying thickness and density into a metal plate and cre-ated marvelous distinctions of tonal values and textures—from smooth skin to rough cloth, from the furry and feathery to the hairy and scaly. The use of cross-hatching (sets of engraved lines at right angles) to describe forms, which Schongauer probably devel-oped, became standard among German graphic artists. The Italians preferred parallel hatching (fig. 21-29) and rarely adopted cross-hatching, which, in keeping with the general Northern Renaissance approach to art, tends to describe the surfaces of things rather than their underlying structures. Schongauer probably engraved Saint Anthony around 1480. By then, the political geography of Europe had changed dramatically. Charles the Bold, who had assumed the title of duke of Burgundy in 1467, died in 1477, bringing to an end the Burgundian dream of forming a strong middle kingdom between France and the Holy Roman Empire. After Charles’s death at the battle of Nancy, the French monarchy reabsorbed the southern Burgundian lands, and the Netherlands passed to the Holy Roman Empire by virtue of the dynastic marriage of Charles’s daughter, Mary of Burgundy (fig. 20-7), to Maximilian of Habsburg, inaugurating a new political and artistic era in Northern Europe, examined in Chapter 23. The next two chapters, however, explore Italian developments in painting, sculpture, and architecture during the 15th and 16th centuries. 590 French ducal courts ■ The most powerful rulers north of the Alps during the first three quarters of the 15th century were the dukes of Burgundy. They controlled Flanders, which derived its wealth from wool and banking, and were great art patrons. Duke Philip the Bold (r. 1363–1404) endowed the Carthusian monastery at Champmol, near Dijon, which became a ducal mausoleum. The head of Philip’s sculptural workshop was Claus Sluter, whose Well of Moses features innovative statues of prophets with portraitlike features and realistic costumes. ■ In the 15th century, Northern European artists popularized the use of oil paints on wood panels. By superimposing translucent glazes, painters could create richer colors than possible using tempera or fresco. One of the earliest examples of oil painting is Melchior Broederlam’s wings of the Retable de Champmol, painted for Philip the Bold. Carved wood narrative reliefs by Jacques de Baerze fill the retable’s interior. ■ The Limbourg brothers expanded the illusionistic capabilities of manuscript illumination in the Book of Hours they produced for Jean, duke of Berry (r. 1360–1416) and brother of King Charles V (r. 1364–1380). Their full-page calendar pictures alternately represent the nobility and the peasantry, always in seasonal, naturalistic settings with realistically painted figures. Flanders ■ A major art form in Flemish churches and private homes alike was the altarpiece with folding wings. In Robert Campin’s Mérode Triptych, the Annunciation takes place in a Flemish home. As is typical of “Northern Renaissance” art, the everyday objects in the triptych have symbolic significance. The largest altarpiece of the era is the Ghent Altarpiece, begun by Hubert van Eyck and completed by his brother Jan. ■ Jan van Eyck, Rogier van der Weyden, and others established portraiture as an important art form in 15th-century Flanders. Their subjects were successful businessmen, both Flemish and foreign, and occasionally themselves. Jan portrayed himself wearing a red turban, and Rogier represented himself in the guise of Saint Luke drawing the Virgin. ■ Among the other major Flemish painters were Petrus Christus and Hans Memling of Bruges, Dieric Bouts of Louvain, and Hugo van der Goes of Ghent, all of whom produced both altarpieces for churches and portraits for the homes of wealthy merchants. van Eyck, Ghent Altarpiece, ca. 1423–1432 de Baerze, Retable de Champmol, 1399 Limbourg brothers, Les Très Riches Heures du Duc de Berry, 1413–1416 France and the holy roman empire ■ During the 15th century, the Hundred Years’ War crippled the French economy, but dukes and mem-bers of the royal court still commissioned some notable artworks. French court art—for example, Jean Fouquet’s Melun Diptych—owes a large debt to Flemish painting in style and technique as well as in the integration of sacred and secular themes. ■ The Late Gothic style remained popular in 15th-century Germany for large carved wood retables fea-turing highly emotive figures amid Gothic tracery. The leading sculptors were Veit Stoss and Tilman Riemenschneider. ■ The major German innovation of the 15th century was the development of the printing press, which publishers soon used to produce books with woodcut illustrations. Woodcuts are relief prints in which the artist carves out the areas around the lines to be printed. ■ German artists, such as Martin Schongauer, were the earliest masters of engraving. The intaglio technique enables a wider variety of linear effects because the artist incises the image directly onto a metal plate. Nuremberg Chronicle, 1493 Fouquet 21-1a Inspired by a poem by Angelo Poliziano, Botticelli painted Birth of Venus for the Medici between 1484 and 1486. At the left, Zephyrus, carrying Chloris, blows Venus on a cockleshell to Cyprus.  21-1b Botticelli’s revival of the theme of the female nude, largely absent from medieval art, was consistent with the Quattrocento view that beholding physical beauty prompts the contemplation of spiritual beauty. 1 ft. 21-1 Sandro Botticelli, Birth of Venus, ca. 1484–1486. Tempera on canvas, 59 90 × 99 20. Galleria degli Uffizi, Florence.  21-1c Awaiting the newborn goddess of love on her sacred island is the nymph Pomona, who runs to meet Venus with a brocaded mantle. Her draperies undulate loosely in the gentle gusts of wind. Copyright

1 - FRAs vs STIRs

principaux ag satures

5D- Gas Transport and Oxyhemoglobin Saturation Curve/ internal and external respiration

Satire Terms

Estate's Satire And The Miller's Tale

oxygen saturations

Role of Disturbance: Periodic disturbances such as fire and mowing can reset ecological succession, but timing is crucial to avoid harming vulnerable life stages. Grassland Ecosystems & Butterfly Conservation Key Drivers of Grassland Decline: Land conversion for intensive row-crop agriculture, urban development, fire suppression, overgrazing, and invasive plant encroachment. Timing is critical: unmanaged disturbances during larval or pupal stages can cause high direct mortality. Butterfly Conservation Concepts: (Amphibian Chytrid Fungus): Waterborne zoospores fungus causing chytridiomycosis in amphibians, disrupting cutaneous electrolyte transport and causing cardiac arrest. Umbrella Species: Species whose broad habitat requirement and spatial area encompass the requirements of many co-occurring species; protecting them indirectly protects the broader community. 3 Main Drivers of Butterfly Declines in the U.S.: Habitat loss and fragmentation, pesticide exposure (neonicotinoids/insecticides), and climate change/phenological mismatch with host plants. Chapter 8: Extinction IUCN Red List & Extinction Metrics IUCN Red List: A standardized framework for assessing species extinction risk based on criteria like population reduction and geographic range. Categories of Extinction: Ranges from Extinct (EX) to Least Concern (LC), providing a comprehensive overview of species status. Extinct (EX) Extinct in the Wild (EW) Critically Endangered (CR) Endangered (EN) Vulnerable (VU) Near Threatened (NT) Least Concern (LC) Data Deficient (DD) Contemporary vs. Background Rates: Current extinction rates are estimated to be 100 to 1000 times higher than historical background rates, indicating a biodiversity crisis. Background Rate: ~0.1 to 1 E/MSY (extinctions per million species-years) based on fossil record averages. Contemporary Rate: Estimated at 100 to 1000x higher than background rates over the last 500 years. Sixth Mass Extinction: Current species loss is unprecedented and primarily driven by human activities, contrasting with past extinction events caused by natural disasters. Extinction Terminology: Globally Extinct: No living individuals exist anywhere on Earth. Extinct in the Wild: Survives only in captivity, cultivation, or managed ex-situ populations. Ecologically / Functionally Extinct: Persists in such low numbers that its interactions no longer significantly influence ecosystem structure or function. Extirpation (Local Extinction): Species is eliminated from a specific geographic region but survives elsewhere. Defaunation: Global downscaling of animal numbers and species diversity within local ecosystems. Population Decay: Progressive loss of localized populations across a species' historical range prior to species level extinction. Mass Mortality Event: Rapid, catastrophic die-off of a large percentage of individuals within a population over a brief timeframe. Extinction Debt: Future expected extinctions resulting from past habitat destruction or degradation that have not yet fully played out demographically. Allee Effects: Positive density dependence where individual fitness or per-capita population growth rate declines at low population densities (e.g., failure to find mates, breakdown of group defense). Ranked Proximate Drivers (Most to Least Threatening Global Impact) Demographic & Life History Risk Factors Ecological & Spatial Risk Factors 1. Habitat Loss & Degradation Low intrinsic rate of population growth (r) High endemicity / narrow geographic range 2. Overexploitation High variability in demographic rates Highly isolated populations 3. Invasive Alien Species Large body size / high trophic position Specialized dietary or microhabitat requirements 4. Climate Change Long generation time / late maturation age Reliance on predictable disturbance regimes Chapter 9a: Habitat Loss Land-Use Transitions & Driver Hierarchy Sequence of Land-Use Transitions: The progression from wildlands to urbanization illustrates the increasing human impact on ecosystems. Main Drivers of Habitat Loss: Agricultural expansion (cropland and livestock pasture) Industrial forestry / timber harvest Urbanization and infrastructure development Aquaculture development (e.g., mangrove clearance for shrimp farming) Vulnerable Ecosystems: Most Historical Loss: Tropical dry forests, temperate grasslands, Mediterranean forests, temperate broadleaf forests. Projected Future Losses: Tropical rainforests, tropical savanna ecosystems, peatlands. Forest Change Patterns: Temperate Forests: Globally stabilizing or re-expanding (forest transition hypothesis), but often replaced by low diversity monoculture tree plantations. Tropical Forests: Experiencing rapid deforesting driven by commodity expansion (palm oil, cattle, soybeans, timber extraction). Boreal Forests: Impacted by large-scale logging, industrial extraction (oil/gas), and accelerating climate-driven fires and insect outbreaks. Pacific Northwest (PNW) Forest Ownership: Federal / State Public Lands: Managed under policies prioritizing ecosystem restoration, old-growth protection, and biodiversity conservation (e.g., Northwest Forest Plan). Private Industrial Lands: Managed primarily for short-rotation timber production, leading to younger stand structures and dense road networks. Chapter 9b: Habitat Degradation and Fragmentation Degradation Mechanisms Primary Forms of Pollution: Nutrient Pollution (Nitrogen & Phosphorus): Agricultural runoff and wastewater leading to eutrophication, rapid algal blooms, and hypoxic dead zones ( <2 mg O2/L). Toxic Chemical Contaminants: Persistent Organic Pollutants (POPs) and heavy metals (e.g., mercury) undergo biomagnification, increasing in concentration up trophic levels. Plastic & Debris Pollution: Mechanical ingestion, entanglement, and chemical leaching in marine and freshwater systems. Desertification: Degradation of dryland ecosystems driven by overgrazing, deforestation, and unsustainable farming combined with drought. Regime Shifts & Tipping Points: Loss of vegetative cover destabilizes topsoil, reduces moisture retention, and creates a self-reinforcing feedback loop that shifts fertile drylands to desert. Prevention Techniques: Terracing, rotational grazing, agroforestry, windbreaks, and soil moisture preservation. Fragmentation & Landscape Mosaics A continuous forest changes into a fragmented forest with gaps, which then divides into separate smaller areas. This leads to edge effects, which are changes that occur at the boundary between the forest and non-forest areas. As a result, there can be shifts in the local climate (microclimate) and some species may become isolated from each other. Fragmentation Effects: Subdivides continuous habitat into smaller patches, reduces core area, and increases edge proportion. Effects on Population Growth & Size: Reduces total core area, creates small subdivided populations, elevates mortality along fragment borders, and limits gene flow. Edge Effects: Abiotic (temperature swings, wind shear, lower moisture) and biotic alterations (higher predation rate, invasive weed establishment) occurring along fragment borders. Metapopulation Concept: A network of spatially isolated local populations ("patches") linked by occasional dispersal. Levins Model: dp/dt= cp(1-p)-ep where P is patch occupancy, C is colonization rate, and E is extinction rate. Source-Sink Dynamics & Ecological Traps: Source Populations: High-quality patches where reproduction exceeds mortality ( r>0), producing emigrants. Sink Populations: Low-quality patches where mortality exceeds reproduction (r<0 ), sustained only by immigration (Demographic Rescue Effect). Ecological Trap: Degraded habitat that provides false environmental cues, attracting organisms to select poor-quality habitat where fitness is reduced Chapter 10: Overexploitation Population Models & Harvesting Theory Logistic Growth Model: dN/dt=rN(1-N/K) Maximum Sustainable Yield (MSY):The peak harvest rate achievable without long-term depletion, mathematically occurring at N= K/2 where population growth rate is maximized (MSY=rK/4 ). Fixed-Quota vs. Fixed-Effort Harvesting: Fixed-Quota (Q ): Removing a constant number of individuals. Highly risky; if stochastic events depress population below N^MSY , quota exceeds growth, driving rapid collapse. Fixed-Effort (E ): Regulating harvesting effort ( EN). Yield scales dynamically with population size, providing stability against collapse. Exploitation Types: Types: Commercial (profit-driven, open-access risks), subsistence (local survival), and recreational (leisure, can fund conservation via game ranches). Global Fisheries Trends: Wild marine capture landings plateaued in the 1990s while aquaculture production expanded rapidly; overfished stock percentages are rising globally. Bycatch & Trophic Downgrading: Unintentional capture of non-target species (sharks, rays, seabirds) and removal of large apex predators, altering marine food webs. CITES (Convention on International Trade in Endangered Species): Regulates international wildlife trade across Appendix I (prohibited/threatened with extinction, e.g., rhinos), Appendix II (strictly controlled, e.g., orchids), and Appendix III (national protection assistance). Chapter 11: Invasive Species Terminology & The Invasion Process Native vs. Non-native Species: Native species exist within their historical range, while non-native species are introduced outside their natural distribution due to human activities. Invasive Alien Species (IAS): Non-native species that establish and spread, causing ecological or economic harm, often outcompeting native species. Invasion Phases: Introduction ---> Establishment (surviving environmental and biotic filters via propagule pressure) ---> spread ( Lag phase ---> Expansion Phase ----> saturation phase) Lag Phase & Expansion Phase: Initial low growth during the lag phase followed by exponential growth in the expansion phase as species adapt to local conditions. Propagule Pressure: Refers to the quantity and quality of introduced individuals, a key predictor of establishment success for invasive species. Establishment Hypotheses: Empty Niche, Novel Weapons (allelopathy), Enemy Release, and Novel Environments. Impacts & Management: Biotic homogenization (B -diversity decline), structural disruption (e.g., Brown Tree Snake in Guam, Zebra Mussels), and management prioritizing early prevention and rapid eradication. Chapter 12a: Climate Change Physical Basis & Projections IPCC Framework: The Intergovernmental Panel on Climate Change synthesizes climate data using Shared Socioeconomic Pathways (SSPs) and Representative Concentration Pathways (RCPs) to project future climate scenarios. Abiotic Trends: Key trends include rising global temperatures, altered precipitation patterns, ocean acidification, thermal expansion, and melting ice sheets, all contributing to sea-level rise. Aerosol Cooling: Industrial aerosol emissions scatter solar radiation, temporarily masking the warming effects of greenhouse gases, complicating climate change mitigation efforts. Climate Feedback Loops: Positive feedback loops, such as melting ice reducing albedo, exacerbate warming, while negative feedbacks can stabilize certain systems. Mitigation Strategies: Emphasizes the importance of reducing greenhouse gas emissions through renewable energy, conservation, and sustainable practices to combat climate change. Global Climate Agreements: Discusses international efforts like the Paris Agreement aimed at limiting global temperature rise and promoting sustainable development. Drivers & Projections: Rising greenhouse gases, aerosol masking, ocean acidification, sea-level rise, and regional PNW shifts (warmer/wetter winters, hotter/drier summers, reduced snowpack). Ecological Impacts: Poleward/elevational geographic range shifts and phenological mismatches decoupling trophic synchrony. Species Distribution Models (SDMs): Algorithms correlating species presence with environmental layers to project future potential ranges. Climate Vulnerability & Conservation Strategies Climate Vulnerability = f(Exposure, Sensitivity, Adaptive Capacity) Climate Refugia: Geographically buffered microenvironments ("slow lanes") providing short-term climate stability. Migration Pathways: Corridors (e.g., Yellowstone to Yukon) linking protected areas to facilitate natural range tracking. Assisted Colonization (Managed Relocation): Deliberately moving species (e.g., Western swamp turtle) to newly suitable habitats when natural dispersal cannot outpace climate velocity. Building Evolutionary Resilience: Maximizing population sizes, preserving genetic diversity, and conducting gene translocations. Agricultural Expansion Agricultural practices, including cropland and livestock pasture, are primary drivers of habitat loss, leading to significant ecosystem degradation. The conversion of forests and grasslands into agricultural land reduces biodiversity and disrupts local ecosystems. Case Study: The Amazon rainforest has seen extensive deforestation for soybean and cattle ranching, impacting global carbon cycles. Industrial Forestry and Urbanization Industrial forestry practices often prioritize monoculture plantations, which lack biodiversity and resilience. Urbanization leads to habitat fragmentation, reducing the core area of habitats and increasing edge effects. Example: Urban sprawl in the Pacific Northwest has led to the loss of temperate forests, impacting local wildlife. Aquaculture Aquaculture expansion can lead to habitat destruction, particularly in coastal areas where mangroves are cleared for shrimp farming. The environmental impact includes water pollution and disruption of local fisheries. Example: The decline of mangrove forests in Southeast Asia due to shrimp farming has led to increased coastal erosion and loss of biodiversity. Vulnerable Ecosystems and Forest Change Patterns Vulnerable Ecosystems Tropical dry forests, temperate grasslands, Mediterranean forests, and mangroves are among the most affected ecosystems historically. Tropical rainforests and savannas are projected to face significant future losses due to climate change and human activities. Historical Context: The Mediterranean region has seen a dramatic decline in forest cover due to agriculture and urbanization. Forest Change Patterns Temperate forests are stabilizing or re-expanding regionally but are often replaced by low-diversity monoculture plantations. Tropical forests are experiencing rapid deforestation driven by commodity expansion, particularly palm oil and cattle ranching. Boreal forests are impacted by logging, industrial extraction, and climate-driven fires, leading to significant ecological changes. Habitat Degradation and Fragmentation Degradation Mechanisms Pollution and biomagnification of persistent organic pollutants and heavy metals pose severe threats to top predators in ecosystems. Nutrient pollution leads to eutrophication, causing algal blooms and hypoxic conditions in coastal areas, creating 'dead zones'. Example: The Gulf of Mexico experiences seasonal dead zones due to nutrient runoff from agriculture, impacting marine life. Fragmentation Effects Habitat fragmentation subdivides continuous habitats into smaller patches, reducing core area and increasing edge habitat. Edge effects alter microclimates, increasing susceptibility to drought, fire, and invasive species. Global Fragmentation Experiments (e.g., BDFFP in Brazil) show that fragmentation negatively impacts ecosystem functions. Overexploitation and Sustainable Harvest Sustainable Harvest Theory The Logistic Growth Model describes population dynamics and sustainable harvesting levels, emphasizing the importance of carrying capacity (K). Maximum Sustainable Yield (MSY) is the peak harvest rate achievable without long-term depletion, mathematically occurring at half the carrying capacity (N = K/2). Fixed-Quota vs. Fixed-Effort Harvesting: Fixed-quota is risky as it can lead to population collapse, while fixed-effort adjusts yield based on population size. Exploitation Contexts Types of exploitation include commercial, subsistence, and recreational, each with different ecological impacts and regulatory needs. Global fisheries trends indicate a plateau in wild marine capture while aquaculture production expands, raising concerns about overfishing. Bycatch and trophic downgrading disrupt marine food webs, leading to ecological imbalances. Invasive Species and Climate Change Invasion Process and Management Definitions: Native vs. non-native vs. invasive alien species (IAS) that cause ecological harm. Invasion stages include introduction, establishment, and spread, with various hypotheses explaining establishment success. Management strategies prioritize early prevention and rapid eradication to mitigate impacts of invasive species. Climate Change Impacts Rising greenhouse gases and climate change lead to shifts in species distributions and phenological mismatches, disrupting ecological interactions. Climate vulnerability is assessed based on exposure, sensitivity, and adaptive capacity, guiding conservation strategies. Assisted colonization may be necessary for species unable to migrate fast enough due to climate velocity.

English Satire/Irony Archetypes

Animal Farm Extras (focuses, satire, and fallacies)

Animal Farm Vocab + Fallacies + Satire

Art History: Weimar Satire, War Trauma, and Major Movements

B1.1.10 - Difference between saturated, monounsaturated, and polyunsaturated fatty acids

12. Fadhbanna ar saoire

Part 3 Oxygen saturation and nursing priorities

29. An introduction to A Level organic chemistry Formulas, Fn groups, Naming Functional groups and formulae Functional group: atom/group of atoms in an organic molecule that determines its characteristic chemical and physical properties Arenes: aromatic compounds that contain a benzene ring chemical properties Compound can undergo Electrophilic attack: is e- rich due to π system of delocalised e- Resistant to addition reactions: delocalised e- ring system makes benzene stable physical properties b.p 80 C: Benzene has id-id forces of attraction between the molecules Insoluble in water: non-polar hydrocarbons in arene (not energetically favourable for benzene to break many H bonds between water molecules to be soluble) Halogenoarenes: aromatic compounds containing halogen bonded to benzene ring chemical properties Prone to Electrophilic attack can take part in substitution reactions physical properties Chloro, broom, iodo benzene liquid at r.t with oily texture b.p. Increases down group: larger halogen = more e- = stronger id-id forces = more energy to separate insoluble in water: non-polar hydrocarbon ring Phenols: aromatic compounds containing a hydroxide bonded to benzene ring chemical properties acidic: O in -OH donates a lone pair into ring (more acidic than alcohols) = increased e- density in ring = more reactive = easier for H to be donated react with reactive metals (e.g. Na) to form phenoloxide ions and H gas physical properties White, crystallline solid disinfectant-like smell soluble in water: can form H bonds with water due to -OH group Acyl chlorides: carboxylic acid derivatives containing a chlorine atom, and an acyl group attached to C=O chemical properties colourless extremely reactive and readily takes part in substitution (Cl substituted ) fuming liquids with strong smell: react with water vapor in air Physical properties react violently with water (cannot determine its solubility with water ) Amines: compounds with -NH2 (primary), -NH (2 °) , or -N (3 ° ) amine group chemical properties basic compounds: due to lone pair of e- on nitrogen physical properties lone pair on N can form H bonds soluble in water: form H bond with water solubility ↓ as nonpolar hydrocarbon chain gets longer / molecule gets bigger fishy smell Amides: compounds containing amine group (-NH2) carbonyl group (C=O) amide group -CONH2 chemical properties less basic than amides: lone pair of e- on N is delocalised physical properties soluble in water: form H bonds with water solubility ↓ as nonpolar hydrocarbon chain gets longer / molecule gets bigger Amino Acids: building blocks of proteins, consisting amine group (-NH2) and carboxylic group (-COOH) chemical properties react with bases to form salts react with alcohols to form esters react with amines to form amides physical properties most are soluble in water but insoluble in organic solvents most have chiral centres, exhibit optical isomers Formulae of Organic Compounds Nomenclature of Compounds Naming organic compounds Identify longest C chain containing the functional group Identify fn group on the chain to determine the suffix or prefix on the compound Count along the carbon chain such that the functional group has the lowest number Add any side chains or lower priority functional groups as prefixes to the beginning of the name in alphabetic order Use the prefixes di-, tri- and tetra- if there are two or more identical functional groups or side chains Characteristic organic reactions Electrophilic substitution Electrophile: e- loving species they are e- deficient and acts as e- pair acceptor Substitution reactions: reactions replacing 1 atom / group by another Electrophilic substitution: group / atom replaced by an electrophile e.g. bromine electrophile attacks e- - rich benzene ring Addition-elimination (nucleophilic) nucleophilic addition of small molecule followed by elimination of small molecule includes hydrolysis reaction of alcohols to form esters reaction with ammonia and 1° amines to form amides e.g. Hydrolysis of acyl chlorides Hydrolysis - acyl chloride to carboxylic acid water molecule adds across C=O bond HCL eliminated Ester formation - acyl chlorides + alcohol Alcohol adds across the C=O bond HCl molecule is eliminated Amide formation - acyl chloride + 1° amines + conc ammonia amine or ammonia adds across C=O bond (lone pair on N attacks carbonyl C atom in acyl chloride) HCl eliminated Shapes of aromatic organic molecules Aromatic molecules consist of one or more rings with conjugated π systems Conjugated π systems arise from alternating double and single bonds in which the electrons are delocalised Shape of benzene and aromatic compounds - why are they more stable? Benzene and other aromatic compounds are planar and regular because each carbon atom is sp² hybridised. Each C forms three σ bonds in a trigonal planar arrangement with bond angles of 120°. The remaining unhybridised p orbital on each carbon overlaps sideways with neighbouring p orbitals to form a continuous, delocalised π system above and below the ring. Because the π electrons are delocalised over the whole ring, all the C–C bonds are identical and have intermediate character between a single and double bond. This is why benzene is unusually stable. Why are benzene more stable? delocalised π electrons above and below the ring Optical isomerism, Chirality and drug production Stereoisomers: same structural formula, diff arrangement in space (geometrical, optical) Optical 4 diff groups of / atoms central chiral carbon chiral molecules exist as 2 optical isomers / enantiomers non-superimposable mirror images same physical / chemical properties rotate in opposite directions in plane polarised light (1 clockwise 1 anticlockwise ) Similarities of enantiomers differences in enantiomers same physical and chemical properties differ from ability to rotate plane polarised light and biological activity nonsuperimposable mirror images Biological activity of enzymes enzymes are chiral proteins, bond to specific active site for biological response mirror image of enantiomer will not bind to same active site as it is not the same shape, no biological response Optical activity and Racemic mixtures reaction mixture is optically active if there is an uneven mixture of each enantiomer (e.g. 20% rotates clockwise, 80% rotates anticlockwise, net effect is plane of polarised light rotates anticlockwise) racemic mixture: equal amounts of enantiomers present in soln optically inactive as enantiomers cancel out each others effect, plane polarised light not changed the rotation of plane polarised light can be used to determine the identity of an optical isomer e.g. pass plane polarised light through a sample containing one of the two optical isomers of a single substance Depending on which isomer sample contains, the plane polarised light will be rotated clockwise / anti-clockwise clockwise rotation: R enantiomer anticlockwise rotation: S enantiomer No effect will be observed when the sample is a racemic mixture Chirality and Drug production most drugs to treat disease have 1+ chiral centres and can ∴exist as enantiomers diff in biological activity in enantiomers means difference in effectiveness as medicine drugs should be prepared so that only 1 optical isomer produced, to ↑ effectiveness Potential different biological activity of enantiomers e.g. drug naproxen treats pain from arthritis 1 enantiomer eases pain 1 enantiomer causes liver damage separate racemic mixture into 2 pure enantiomers due to difference in biological activities reduce side effects ↓ dosage by half, reduces production cost chiral catalysts to produce 1 pure optical isomer only small amount chiral catalysis needed + reused e.g. enzyme 30. Hydrocarbons - Arenes Reactions of arenes substitution halogenation nitration Friedel-Craft's alkylation Friedel-Craft's acylation other reaction Complete Oxidation Hydrogenation Electrophilic substitution electrophile: e- pair acceptor, attracted to delocalised e- substitution: 1+ H replaced by a fn group generating electrophile+ using catalyst Electrophilic attack on benzene ring (electrophile accepts 2 π e- , +ve charge remains) regenerating aromaticity by heterolytically cleavage of C-H bond (bonding pair foes into benzene π system) Addition reactions of arenes arenes undergo substitution due to delocalisation of e-, aromaticity restored by heterolytic cleavage of C-H bond in addition, aromaticity / stability not restored (e.g. hydrogenation), Hydrogenation of benzene is less exothermic than expected for three isolated C=C bonds, because the aromatic stabilisation of benzene is lost Halogenation (in the aromatic ring) reactants: Cl2 / Br2 (Cl+ / Br+ electrophile) , arene conditions: rt and pressure catalyst: anhydrous AlCl3 / AlBr3 (catalyst needed due to stability of benzene structure) formation: AlCl3 + Cl2 ⇒ AlCl4- + Cl+ reformation: H+ + AlCl4- ⇒ AlCl4 + HCl product: halogenoarenes / aryl halide In halogenation of Alkylarenes, e- donating alkyl group activates positions 2, 4 (as well as OH-, NH2). forms 2 products multiple substitutions when excess halogen used Halogenation (of alkylarenes) in side chain free radical substitution reaction reactants: halogen, boiling alkyl arene conditions: UV light if excess halogen: all H on alkyl side chain will be substitution by X atoms Nitration reactants: conc HNO3 (NO2+ electrophile), arene conditions: 20-60 ° C (higher = more NO2+ substituted) catalyst: conc H2SO4 formation: HNO3 + H2SO4 ⇒ NO2+ + 2HSO4- + H3O+ reformation: H+ + HSO4- ⇒ H2SO4 In nitration of Alkylarenes, e- donating alkyl group activates positions 2, 4 Friedel-Crafts alkylation substitution of alkyl chain reactant: chloroalkane (CH3CH2+ electrophile), arene condition: heat under reflux catalyst: anhydrous AlCl3 formation: AlCl3 + CH3CH2Cl ⇒ CH3CH2+ + AlCl4- reformation: AlCl4- + H+ ⇒ AlCl3 + HCl Friedel-Crafts acylation substitution of an acyl group (group containing carbonyl, C=O ) reactant: acyl chloride (CH3CH2CO+ electrophile) conditions: heat under reflux catalyst: anhydrous AlCl3 formation: AlCl3 + CH3CH2COCl ⇒ CH3CH2C=O+ + AlCl4- reformation: AlCl4- + H+ ⇒ AlCl3 + HCl Complete oxidation of side chains alkyl side-chains in alkyl arenes are oxidised to carboxylic acids when refluxed with alkaline KMnO4 and then acidified with dilute H2SO4 reactants: hot alkaline KMnO4, dilute H2SO4, alkyl arenes conditions: heat under reflux Hydrogenation addition reaction to form cyclohexane reactants: H2 gas conditions: heat (200 ° C at 30 atm ) catalyst: Pt/Ni Directing effects of substituents on arenes substituents: already on arene that direct substitution reactions to diff. ring positions E- withdrawing groups / substituents e- donating groups / substituents remove e- density from π system in benzene ring deactivating groups (slow attack by e+) directs e+ to positions 3, 5 e.g. COOH, X, NO2 donate e- density into π system of benzene ring activating groups (allow e+ to react faster) directs e+ to positions 2, 4, 6 e.g R, NH2, OH 31. Halogen compounds Halogenoarenes: arenes bonded to X atoms Producing halogenoarenes substitution reactions of arenes with chlorine or bromine in presence of anhydrous AlCl3 catalyst reactants: Cl2 / Br2 (Cl+ / Br+ electrophile) , arene conditions: rt and pressure catalyst: anhydrous AlCl3 / AlBr3 (catalyst needed due to stability of benzene structure) formation: AlCl3 + Cl2 ⇒ AlCl4- + Cl+ reformation: H+ + AlCl4- ⇒ AlCl4 + HCl product: halogenoarenes / aryl halide Substitution of benzene Substitution of methylbenzene substitution of 6 position only occurs in excess chlorine Reactivity of halogenoarenes Why are aryl halides less reactive than haloalkanes? C-H bond in aryl halides is stronger due to the partial overlap of lone pairs on halogen atom with the π system in the benzene ring C-H bond ∴ has a partial double bond character 32. Hydroxy compounds Reactions of alcohols Formation of esters reaction: addition-elimination (esterification) reactants: alcohols/phenols, acyl chlorides nucleophile: OH- (attacks e- deficient carbonyl (COCl) C ) COCl bond breaks, Cl is substituted, HCl fumes formed Why are esters formed from acyl chlorides rather than from C. acids? more effective to form esters from acyl chlorides acyl chlorides are more reactive (produce esters faster) acyl chloride reactions go to completion (more ester formed) Esterification using phenols additional reactants: base (e.g. NaOH) base: deprotonate phenol to form phenoxide ion phenoxide better nucleophile than phenol, attack on carbonyl C occurs more readily Phenol phenol: benzene ring with -OH group attached Production of Phenol From reaction of phenylamine with nitrous acid (HNO3) reactants: NaNO2, dilute acid (to form HNO2), phenylamine conditions: ice (under 10 ° C) step 1 and 2, heat step 3 forming nitrous acid NaNO2 + HCl ⇒ (ice) HNO2 + NaCl forming unstable diazonium salt forming phenol via thermal decomposition (due to instability) reactions of phenol Many reactions due to e- rich benzene ring and polar -OH group with bases with reactive metals with diazonium salts nitration bromination Acid-base reactions Acid-base reaction of phenols with base -OH: slightly acidic (weak acids), act as acid in acid-base reaction dissolve in alkaline soln forming phenoxide salt and water Acid-base reaction of molten phenols with reactive metals forms soluble phenoxide salt and H2 gas Reaction with diazonium ions diazonium ions very reactive due to -N2+ group acid-base reaction conditions: ice for cold diazonium ion added to phenoxide ion Reactions of the aromatic ring phenols react more readily with e+ than benzene due to one lone pair of e- on O in -OH overlaps with π bonding system, ↑ e- density of phenol’s benzene ring and making it more susceptible to electrophilic attack -OH activates ring, directs e+ to 2, 4, 6 positions Nitration of phenols electrophilic substitution reaction reactant: dilute HNO3, phenol when conc HNO3 used, product is 2, 4, 6- trinitrophenol conditions: rt milder conditions as phenol is more reactive Bromination of phenols electrophilic substitution reaction reactants: bromine water, phenol conditions: rt phenol decocolourises orange bromine soln to form 2, 4, 6 - tribromophenol (white ppt) as phenol is more reactive, no need for anhydrous AlBr3 catalyst, can react with bromine water Reactions of other phenolic compounds (contain phenol functional group, e,g, 1-naphthol) -OH group is also e- donating, activates benzene ring to electrophilic substitution reactions, e+ directed to 2, 4 positions (on phenol) C in position 6 shared by both rings, no H atom = no substitution can react in similar way as phenol Acidity of phenols Phenols are weak acids phenols react more readily with e+ than benzene due to one lone pair of e- on O in -OH overlaps with π bonding system, ↑ e- density of phenol’s benzene ring and making it more susceptible to electrophilic attack Phenol’s conjugate base is the phenoxide ion. -ve charge is delocalised over the entire ion as a lone pair on O overlaps with the ring’s delocalised π system, which reduces charge density on oxygen H⁺ ions are ∴ less strongly attracted to phenoxide ion, so phenol is less likely to reform Therefore, phenol is more likely to lose H⁺ and act as an acid Stability of conjugate base phenoxide more stable as -ve charge spread out, so phenol more likely undergo ionisation eqm shifts right, more phenol donate H+ (act as acid) Relative acidities of water, phenol, ethanol smaller pKa = stronger acid order of acidity explained by conjugate bases Delocalisation of charge density phenoxide (conjugate base of phenol): charge density of O is spread out over ion, O less available for bond formation with H+ ethoxide (conjugate base of ethanol): ethyl group is e- donating, donates e- density to O atom, O more available for bond formation with H+ hydroxide (conjugate base of water): charge density of O cannot become delocalised over a ring, OH- more readily accepts H+ than phenoxide no e- donating alkyl groups to O, less -ve O, O less readily accepts H+ compared to ethoxide Overall conjugate base more readily accepts H+ = stronger conjugate base = weaker acid strong acid eqm shifts right favouring dissociated ions and H+ 33. Carboxylic acids and derivatives Benzoic acid: C6H5COOH can be used to synthesize esters Carboxylic acids Production of benzoic acid formation of benzoic acid from Oxidation of alkylbenzenes alkylbenzene heated under reflux with hot alkaline KMnO4, then acidified with dilute acid to protonate carboxylate salt and form benzoic acid reactants: hot alkaline KMnO4 (oxidising agent), dilute acid (e.g. HCl), alkylbenzene purple Mn2+ turns colourless as reduced to Mn4+ brown ppt MnO2 formed conditions: heat under reflux Reactions of Carboxylic acids Reactions of C, acids to form acyl chlorides reactants PCl5 (s) PCl3 (l) + heat SOCl2 (l) Forming carboxylic acids from oxidation of 1 ° alcohols alcohol ⇒ aldehyde ⇒ c. acid Further oxidation of c. acids such as methanoic and ethanedioic acid methanoic acid (strong reducing agent) gets further oxidised to CO2 by warming with mild oxidising agents like Fehling’s or Tollen’s reagent Fehlings: Cu2+ reduced to Cu+, form red ppt Cu2O Tollens: Ag+ reduced to Ag using stronger oxidising agents like acidified KMnO4 or acidified K2Cr2O7 KMnO4: purple soln turns colourless as Mn7+ reduced to Mn2+ K2Cr2O7: orange soln turns green as the Cr6+ reduced to Cr3+ ions Ethanedioic acid gets further oxidised to CO2 Conditions: Strong oxidised agent - warm acidified KMnO4 needed Relative acidities of C. acids, Phenols, and alcohols C acids can lose H+ in aq soln to form carboxylate salts and water Acidities of C. acids longer C chain = weaker acid inductive effect ↑ -ve charge on COO- group More substituted Cl atoms = stronger acid Cl atoms withdraw e- density from the –COOH group, weakening the O–H bond and stabilise carboxylate ion (reducing the -ve charge density on it) The more stable the carboxylate ion, the less likely it is to attract H⁺ and reform the O–H bond Acidities of c. acids, phenols, alcohols acidities explained by strength of O-H bond and stability of conjugate bases of acids Strength of O-H bond carboxylic acids e- in O-H bond drawn towards C-O bond, e- in C-O bond drawn to C=O bond O-H bond weakened due to C=O withdrawing e- density from it for itself easier to act as acid and lose H+ from OH alcohols lack e- withdrawing C=O group, O-H bond not weakened harder to act as acid and lose H+ Stability of conjugate bases carboxylate ion (c base of carboxylic acid) charge density on O spread over ion because charge is delocalised on an electronegative carbonyl O atom O less available for bond formation with H+ to reform -COOH eqm shifts right, C base more stable than carboxylic acid alkoxide ion (c base of alcohol) alkyl is e- donating group, donates e- density to O atom O more available for bond formation with H+ ion to reform OH lack ability to delocalised charge density on ion, c bases less stable than alcohols, weaker acids than c. acid and phenols eqm lies left phenoxide ion (c base of phenol) charge density of O spread out over ion due to delocalisation of e- (stabilises ion) O less available for bond formation with H+ Phenoxide more stable than phenol Phenoxide less stable than carboxylate since delocalisation of charge density is on C atoms, not electrogenative O atoms eqm lies more right than alcohols, more left than c. acids ethanol is weakest e- donating methyl group strengthens O-H bond methyl donates -ve charge to -COO-, more likely to accept H+ Esters - Production Esters: organic compounds with -COO- functions group nice smelling Naming esters alcohol acyl chloride / carboxylic acid e.g. Producing esters from alcohols and carboxylic acids condensation / esterification reaction Producing esters from alcohols and acyl chlorides more effective: acyl chlorides more reactive(faster), and reactions go to completion (no eqm, max yield) Acyl Chlorides Acyl chlorides: compounds with COCl fn group Production of acyl chlorides Carboxylic acid with solid PCl5 liquid PCl3 + heat liquid SOCl2 Reactions of acyl chlorides addition-elimination: addition of small molecule across C=O, followed by elimination of small molecule acyl chlorides under addition-elimination reactions such as hydrolysis to form carboxylic acid Reaction with alcohols and phenols to form esters Reaction with ammonia and amines to form amides General mechanism for addition-elimination reactions addition of nucleophile across C=O bond elimination of a small molecule such as HCl or H20 lone pair on nucleophile carries out initial attack on carbonyl carbon this is followed by the elimination of an HCl molecule Hydrolysis of acyl chlorides forms carboxylic acid and HCl water (nucleophile) adds across C=O bond HCl eliminated Formation of esters from acyl chlorides esterification reaction reactants: alcohol/phenol, acyl chloride conditions: rt reaction with phenol is slower than alcohol, base such as NaOH used to speed up reaction (deprotonates phenol to form phenoxide, better nucleophile to carry out attack) alcohol /phenol (nucleophile) adds across C=O bond, HCl / NaCl eliminated Formation of amides from acyl chlorides condensation reaction: nucleophile adds to C=O, Cl- eliminated, HCl formed reactants: ammonia or 1°/2 ° amines, acyl chloride nucleophile: Nitrogen (has lone pair of e- ) HCl formed is immediately neutralised by a 2nd molecule of ammonia / amine in excess, forming ammonium salt (e.g. NH4Cl, CH3NH3Cl) Relative ease of hydrolysis of aryl chlorides from most readily broken / easily hydrolysed acyl chloride > alkyl chloride > aryl chloride trend explained by strength of C-Cl bond acyl chlorides - hydrolysed at rt R-COCl C bonded to Cl is also bonded to O both Cl and O are very electronegative, pulling e- away from C, leaving it very δ+ C-Cl bond is weakened nucleophilic attack is more rapid alkyl chloride - hydrolysed by refluxing with strong alkali nucleophile R-C-Cl C bonded to Cl attached to 1 electronegative atom (Cl), pulls e- away from C C is not very δ+ (e- deficient) C-Cl bond is stronger than in acyl chlorides aryl chlorides - hydrolysis will not occur C bonded to Cl is part of delocalised π bonding system of benzene ring one lone pair of e- on Cl overlaps with delocalised system C-Cl bond has some double bond character, becoming stronger 34. Nitrogen compounds Primary and secondary amines 1 ° amines: organic compounds with NH2 fn group attached to an alkyl / aryl group 2 ° amines: organic compounds with group attached to a alkyl /aryl groups Naming -amine: after alkyl prefix (e.g. methyl amine) amino- : if another suffix present or branched/complex amines (e.g. amino methane) Production of Amines 1 ° and 2 ° amines prepared form diff reactions 1 ° amines: reaction of haloalkanes with ammonia reduction of nitriles reduction of amides 2 ° amines: reaction of haloalkanes with 1 ° amine Forming 1 ° amines from haloalkanes with ammonia nucleophilic substitution reaction reactants: excess, hot ethanolic ammonia nucleophile: N in ammonia (replaces X) conditions: heat under pressure Forming 1 ° amine from reduction of nitrile reactants: nitrile vapour, H2 gas conditions: LiAlH4 in dry ether (reducing agent), or Ni catalyst Forming 1 ° / 2 ° amines from reduction of amides reactants: LiAlH4 in dry ether (reducing agent) type of amine depends on nature of amide Forming 2 ° amines from haloalkanes with 1 ° amine nucleophilic substitution reaction reactants: 1 ° amine in ethanol nucleophile: N in 1 ° amine (replaces X) conditions: heat under pressure, sealed tube Reactions of Amines Condensation reaction between Acyl chloride and ammonia or amine produces Amides Cl in acyl chlorides is electronegative, draws e- density from carbonyl C C is e- deficient, attacked by nucleophile like N in ammonia and amines C-Cl bond broken, amide formed reaction with amines ⇒ substituted amide reaction with ammonia ⇒ nonsubstituted amide Why is acyl chloride a more effective reactant than carboxylic acids in formation of amides? c acids less reactive than acyl chloride reaction with c acids dosent fo to completion Basicity of aq soln of Amines and ammonia N in ammonia and amines can accept proton H+, can ∴ act as bases in aq soln (when donating lone pair to form dative bonds) Strength of bases strength of amine depends on availability of lone pair of e- on N to form a dative covalent bond with H+ lone pair more readily available to form dative bond = stronger base positive inductive effect ↑ basicity: alkyl groups donate e- density to N, causing lone pair to become more available delocalisation ↓ basicity: aromatic rings cause lone pair to be delocalised into benzene ring, causing lone pair to be less available Phenylamine and Azo compounds Phenylamine: organic compound with benzene ring and amine fn group Production of phenylamine 3 step synthesis, followed by separation / purification Nitration (forming nitrobenzene) reactants: benzene, conc HNO3 catalyst: conc H2SO4 conditions: 25-60 ° C Reduction (forming phenylamine ion) conditions: hot tin (Sn) and conc HCl under reflux Deprotonation (forming phenylamine) reactants: NaOH, phenylamine ion separation/purification phenylamine separated from reaction mixture by steam distillation Reactions of Phenylamine Both benzene ring and NH2 can take part in chemical reactions bromination of phenylamine formation of diazonium salt Bromination of phenylamine to form 2, 4, 6- tribromophenylamine electrophilic substitution reaction electrophile: N, donate e- density into benzene ring, ↑ e- density in benzene ring activates it, more readily attacked by electrophiles reactants: aqueous bromine, phenylamine conditions: rt Formation of diazonium salt (salt containing N2+ group) reactants: nitrous acid/HNO2, HCl, phenylamine HNO2 formed in test tube with NaNO2 and dilute HCl conditions: below 10 ° C diazonium salt forms phenol upon warming with water Azo compounds Azo compounds: organic compounds with R-N=N=R / azo group often used as dyes Diazonium compounds: contain N2+ group Formation of Azo compounds from coupling reaction of benzene diazonium chloride salt with phenol multi-step process forming nitrous acid reactants: NaNO2, HCl conditions: test tube, under 10 °C / ice NaNO2 + HCl ⇒(ice) HNO2 + NaCl Diazotisation reactants: phenylamine, HNO2, dilute HCl conditions: below 10 ° C / ice (prevent thermal decomposition of diazonium ion to phenol, N and HCl) coupling reaction reactants: phenol, diazonium ion (acts as electrophile, sub into benzene ring of phenol) conditions: alkaline conditions (NaOH deprotonates phenol to phenoxide, more reactive to e+) Why are azo compounds very stable? The delocalised e- in π bonding systems extend across both benzene rings and the –N=N– bridge Other days formed from similar route e.g. formation of yellow dye from coupling reaction between benzene diazonium chloride and C6H5N(CH3)2 Amides Amide: organic compounds with CONR2 amide group non-substituted / 1 ° amide: N bonded to 2H atoms substituted / 2 ° amide: 1 or both H replaced by a hydrocarbon group Production of Amides Formation of Amides from acyl chlorides / c. acid with ammonia / amine condensation reaction: nucleophile adds to C=O, Cl- eliminated, HCl formed nucleophile: Nitrogen (has lone pair of e- ) conditions: rt HCl formed is immediately neutralised by a 2nd molecule of ammonia / amine in excess, forming ammonium salt (e.g. NH4Cl, CH3NH3Cl) Reactions of Amides Amide group can undergo reactions Hydrolysis with aqueous alkali or aqueous acid Reduction with LiAlH4 Hydrolysis of amides to form c. acid and ammonia/ 1 ° amine conditions: reflux with aq acid / alkali products differ depending with amide is substituted nonsubstituted ⇒ c. acid + ammonia substituted ⇒ c. acid + 1 ° amine when refluxed in excess acid⇒ ammonium salt formed base⇒ carboxylate ion formed (deprotonation) Reduction of amides to form amine conditions: LiAlH4 reducing agent nonsubstituted amide ⇒ 1 ° amine + H2O substituted amide ⇒ 2 ° amine + H2O Relative basicity of Amides and Amines lone pair of e- more readily available for dative bonding = stronger base more e- =stronger base amides - weaker base e- withdrawing O in C=O causes lone pair on N to delocalise into C=O group, removed e- density from N lone pair on N less readily available for bonding amine - stronger base e- donating alkyl groups ↑ e- density on N lone pair on N more readily available for bonding Amino Acids Amino acids: organic compounds with 2 fn groups basic amino -NH2 group acidic carboxylic acid -COOH group due to presence of basic and acidic group, they are amphoteric (act as acid and base) R group can be acidic, basic, or neutral Acid-base properties of amino acids + formation of Zwitterion amino acids can undergo most reactions of amines and c. acids, including acid-base reactions (amine + acid, C. acid + base) Amino acids can interact intramolecularly to form zwitterion Zwitterion: ion with both +ve (NH3+) and -ve (COO-) charge formed from amino acids in water due to charges, there are strong intermolecular forces of attraction between amino acids this makes amino acids soluble crystalline solids Zwitterions act as buffer soln acid added: pH ↓ COO- accepts H+ to reform COOH, zwitterion becomes +vely charged base added: pH ↑ NH3+ donates H+ to reform NH2, zwitterion becomes -vely charged Isoelectric point: point at which charge = 0 / zwitterion is neutral a pH level unique to each amino acid due to R group Formation of Peptide bonds NH2 group of one amino acid can react with COOH group of another amino acid to form dipeptide condensation reaction: H2O eliminated peptide bond / link formed dipeptides can undergo condensation reaction again to form tripeptide ( 3 amino acids) polypeptide: many amino acids join to form long chain of molecules proteins are polypeptides Electrophoresis Analytical separation technique, separates ions by placing them in an electric field Sample of amino acids placed between 2 oppositely charged electrodes +ve ions move to -ve electrode -ve ions move to +ve electrode Rate of ion movement depends on size of ions (larger = slower) charge of ions (highly charged = quicker) Electropherogram: bands on gel after electrophoresis each band = particular species Amino acids can be separated according to charge and mass they are colourless, sprayed with ninhydrin (brown/purple stain) to show where they have gone to Changes in charge of amino acid due to pH of solution isoelectric point: no overall charge, no movement of zwitterions pH > isoelectric point: -ve charge, move to +ve electrode pH < isoelectric point: +ve charge, move to -ve electrode -ve charged amino acid: NH3+ donated H+, NH2 and COO- left +ve charged amino acid: COO- accepted H+, NH3+ and COOH left 35. Polymerisation Condensation Polymerisation - Forming polymers Forming polymers such as polyesters, polyamides, proteins Formation of polyesters addition polymerisation: monomers with C=C bonds join to form polymers condensation polymerisation: Small molecule is lost when monomers join together to form polyester polyesters have ester links Monomers for polyesters OH on dicarboxylic acid and H of diol expelled as H2O to form polyester diol (2 -OH) + dicarboxylic acid (2 -COOH) 2 hydroxy carboxylic acids (OH and COOH fn group) Formation of polyamides condensation polymerisation polyamides have peptide links Monomers for polyamides H on diamide and OH on dicarboxylic acid / Cl on dichloride expelled as H2O / HCl as polyamide forms diamide (2 -NH2) + dicarboxylic acid diamide + dichloride (2 -COCl) 2 aminocarboxylic acids (OH and COOH fn group) Making proteins/polypeptides from amino acid monomers (aminocarboxylic acid) amine group (-NH2) and carboxyl group (-COOH) of an amino acid polymerise with another amino acid forms peptide links proteins can be broken into its constituent amino acids through hydrolysis You can deduce the repeat units of a condensation polymer by identifying the linking between monomers chain of C: addition polymer ester link: polyester peptide link: polyamide You can identify monomers from small molecule expelled H2O: c acid H: amine Cl: dioyl chloride Predicting type of polymerisation Identifying type of polymerisation by looking at functional groups Addition polymerisation monomer contains C=C bond double bond opens up to add monomers to either side of starting polymer forms polyalkenes co-polymer: 2+ monomers used to make 1 repeating unit Condensation polymerisation makes polyamides and polyesters summary: Identifying type of polymerisation by considering structure of polymer backbone Addition polymerisation no fn groups on polymer backbone, usually chain of C atoms sidechains might branch off from backbone (e.g. benzene rings, nitrile groups (CN), halogens Condensation polymerisation backbone of polyesters contain ester links (-COO-) backbone of polyamides contain peptide links (-CONH-) Degradability of Polymers Polyalkenes and biodegradability polyalkenes are nonpolar and saturated, making them nonbiodegradable and chemically inert instead, they can be melted and recycled for new uses The energy released from burning can be used to generate electricity Burning plastics in oxygen releases carbon dioxide and water (complete combustion) which can contribute to global warming Photodegradation of polymers some polymers are biodegradable due to their ability to breakdown using light C=O groups along polymer chains absorb UV light this weakens C=O areas of polymers and breaks them down into smaller molecules e.g for polyesters and polyamides Disadvantages of photodegradability weaker polymers UV light not available (e.g. in landfills) Biodegrading polyesters and polyamides via hydrolysis polyesters and polyamides can be broken down by hydrolysis (advantage) hydrolysis: breakdown of molecules using water acid hydrolysis: acid catalyst used alkaline hydrolysis: alkaline catalyst used heating with catalyst breaks polymer Hydrolysis of polyamides acid hydrolysis: breaks polymer into di carboxylic acid and ammonium ions alkali hydrolysis breaks polymer into its sodium salts (e.g. dicarboxylic acid salt and diamines) Hydrolysis of polyesters acid hydrolysis: diol + dicarboxylic acid alkali hydro lists: diol + dicarboxylic acid salt 36. Organic synthesis Elucidating organic molecules - fn groups, properties, reactions Fn groups in AS required as well as: Production of fn groups benzoic acids acyl chlorides amides Producing benzoic acid reactants: methylbenzene oxidation: reflux with hot alkaline KMnO4 to form potassium benzoate protonation with dilute HCl to form benzoic acid Producing acyl chlorides reactants: c. acid substitution reaction: -OH replaced by Cl Producing amides condensation reaction reactants: acyl chloride, NH3 (nonsubstituted amide) / methyl amine (substituted amide) conditions: rt Reactions of functional groups Electrophilic substitution reactions of benzene reaction electrophile halogenation X+ nitration NO2+ alkylation R+ acylation RCO+ Hydrogenation of benzene addition reaction Esterification of phenol more efficient with acyl chloride than carboxylic acid Acid-base reactions of phenol phenol + base ⇒ soluble salt + water Nitration of phenol Bromination of phenol Multi-step synthetic routes Aliphatic reactions Aromatic reactions Analysis 37. Analytical techniques Thin- Layer Chromatography (TLC) Separate small samples 2 phases: stationary and mobile phase Stationary phase thin metal sheet coated in Al2O3, or SiO2 solutes adsorb onto surface and travel thru plate Mobile phase flows over stationary phase polar (water or alcohol) or nonpolar (alkanes), any liquid solvent or gas solvent carries components investigated in coloured components: investigated under UV light using ninhydrin Conducting a TLC analysis prep beaker with small amount of solvent on TLC plate, draw baseline in pencil place spot of reference compound on the left, then a spot of sample on right of baseline and air dry reserve allows identification of compounds in sample put TLC plate inside beaker with solvent - make sure pencil line above solvent, place lid to cover beaker as solvent reaches top, remove plate and draw another pencil line where solvent reached (solvent front) to use to calculate Rf Rf values The extent to which components are separated depends on solubility of each component in the mobile phase and interaction between each component and the stationary phase less polar components travel further up ⇒ larger Rf ⇒ more soluble in mobile phase more polar components do not travel far up ⇒ more attracted to polar stationary phase Gas / Liquid chromatography Analysing bases, volatile liquids, solids in vapour form Stationary phase nonpolar, non-volatile liquid applied to the inner walls of a capillary column mobile phase unreactive carrier gas noble, or inert diatomic e.g. He, N2, Ar Retention time: time taken for sample molecule to travel through the column from time inserted to time detected often recorded on chromatogram each peak = a volatile compound in the analysis sample. each peak has its own rt rt compared with data book values to identify unknown molecules longer rt: nonpolar components, attractiveness to nonpolar liquid in stationary phase shorter rt: polar components, interact with carrier gas Relative concentration of each component = area under each peak Area under peak = ½ base x height peaks roughly take shape of Δ % composition of a particular molecule in a mixture Carbon-13 NMR spectroscopy carbon-13 NMR : analytical tool used to analyse samples and determine the structure of substances Each Carbon environment gives a peak solvent used to dissolve samples for 13C-NMR : CDCl3 (solvent peak around 70 ppm) all 13C-NMR spectra measured relative to TMS / tetramethylsilane ( 0 ppm) predict the number of carbon environments refers to a specific c atom and the combination of atoms, bonds, fn groups attached each unique c environment produces a peak in 13C - NMR if there is a line of symmetry through the molecule, they belong to same environment and product a single peak e.g. predict no. peaks in 13C-NMR spectrum of 1,3-dihydroxybenzene 4 environments = 4 peaks predict each carbon’s chemical shift this is the frequency of an atomic nucleus relative to TMS reference compound measured in ppm example- 13C-NMR spectrum for propanone both CH3 groups are in same environment 2 environments = 2 peaks C=O peak over 200 C-H peaks 0-50 Proton (1H) NMR spectroscopy Technique used to determine structure of molecules paired with other techniques like Mass spec Magnetic field strengths of protons in organic compounds measured and recorded on H NMR spectrum all samples measured against reference compound TMS / Tetramethylsilane single sharp peak at 0 ppm Sample peaks plotted as a ‘shift’ away from this reference peak gives rise to ‘chemical shift’ values for protons on the sample compound (measured in ppm) Features of NMR spectrum intensity of peak against chemical shift area under peak: no. protons in particular environment height: intensity / absorption from protons Molecular / chemical environments diff. arrangements of H atoms have diff environments (identical / symmetry = same environment) no. environments = no. diff chemical shifts / peaks e.g. How many different 1H chemical environments occur in 2-methylpropane? 2 1H chemical environments 2 peaks on 1H NMR spectrum Chemical shift values for H molecular environments symmetrical H = same environment 1 ppm → Alkane 2 ppm → Next to C=O 7 ppm → Benzene ring 9–10 ppm → Aldehyde 10–12 ppm → Carboxylic acid Low resolution 1H NMR peaks on a low resolution NMR spectrum refer to the molecular environments of an organic compound High resolution 1H NMR number of peaks a signal splits into = n + 1 n = number of H on adjacent C atom n+1 splitting patterns Common pairs of splitting patterns TMS and deuterated solvents TMS gives sharp peak at 0 on NMR spectrum why is TMS an ideal reference chemical? it is inert and volatile it reduces undesirable chemical reactions with compound analyses it mixes well with most organic compounds Deuterated solvents in 1H NMR CDCl3 used as a solvent, no peak why is a solvent needed for samples in 1H NMR? dissolving samples in solvent help separate molecules and prevent them from interacting what must the solvent do? be a good solvent for organic molecules not contain any H atoms, does not interfere with NMR signals examples of non-deuterated solvents Carbon tetrachloride, CCl4: This solvent does not contain hydrogen, so it does not produce 1H NMR signals. It is suitable for 1H NMR but does not dissolve all molecules well. examples of deuterated solvents Deuterated solvents are often used in 1H NMR because deuterium (²H) is an isotope of H whose nuclei absorb in a different region from protons, so it gives no signal in a ¹H NMR spectrum Deuterochloroform / Chloroform-d, CDCl3: preferred, contains deuterium (2H) instead of H, does not interfere with the H NMR Deuterium oxide / Heavy water, D2O: deuterium atoms exchange reversibly with the H in the -OH and -NH, signals identified in NMR Identifying -OH and -NH signals Protons in -OH (hydroxyl) and -NH (amine) groups give singlet peaks in ¹H NMR but these signals can be tricky: peaks are broad or sometimes fall outside normal chemical shift ranges H in these groups exchanges quickly with protons from water or acids, so only one peak appears Their chemical shift ranges may overlap with other types of protons To identify these groups more clearly, proton exchange with deuterium oxide (D2O) is used: The deuterium atoms in D2O exchange reversibly with the protons in the -OH or -NH groups -OH + D2O ⇌ -OD + HOD -NH-CO- + D2O ⇌ -ND-CO- + HOD Since deuterium does not absorb in the same region as protons in the NMR spectrum, the signal for -OH or -NH disappears after D2O is added This confirms the presence of -OH or -NH groups in the molecule If peak disappears after D2O, it is due to the exchange of a proton from an -OH or -NH group

CHEM 100B LEC - Saturated Hydrocarbons

Saturated Fatty Acids

1.14 Triglycerides, saturated and unsaturated fatty acids

Satire Quiz