Builders and poets of Rome
The character of the Roman cultural period, which was prolific in a number of successful expansion-wars and architectural developments, was based on power play and the expression thereof. Whereas the Egyptian cultural heritage can be seen as a product of First Quadrant-thinking (living with the gods) and the Greek cultural period as a Second Quadrant phenomena (living with the philosophers), so the Roman Empire seemed to be a representation of the Third Quadrant stage in a quadralectic approach (living with the warriors). Naturally, this is a gross simplification of historical reality, which does not account for all the atrocities committed by the Egyptians and Greek in their fights, but can, nevertheless, be used as a global characterization of the major classical civilizations (from a modern point of view).
Furthermore, the Roman warriors got, returning from their battles, an appetite for the spiritual things in life. A lack of ‘culture’ became immanent following the military successes in the third century BC, while fighting the Punic wars against the Carthaginians. The occupations of artist and warrior were difficult to combine. The Romans were of the opinion that ‘art’ was not man-like and more suited for foreigners, who lost their dignity as fighting man (GRIFFIN, 1986). Consequently, Rome had to import its culture. In particular, between 250 and 200 BC a great interest in Greek culture was aroused. The years between 200 and 100 BC saw a Roman world flooded with (foreign) art. And from 133 BC onwards, HAFNER (1983) speaks of a downright plundering.
It was, maybe due to the above described violent nature (of acquiring visibility), that the fourfold way of thinking was a relative late development in the Roman cultural period and took mainly place after the conquest of Greece (133 BC) and the subsequent robbing of its cultural and philosophical heritage. If the Roman cultural period is dated between 750 BC and 500 AD, this visibility-point (of the tetradic way of thinking) is about halfway in time, i.e. in the middle of the Third Quadrant.
However, it must be remembered that the first Greek influences on the Roman civilization already started around 480 BC. Therefore, it can be concluded, that the acquaintance with certain aspects of Greek thoughts (including the tetrad form) must have taken place from this earlier date onwards.
Attention is drawn here with regards to the anticipation of tetradic thinking, to the use of the term ‘Roma quadrata’. This description, as part of the history of the city of Rome, pointed to a four-fold division of Rome (Urbs quattuor regionum) and will be briefly described in its historical context.
In the pre-Etruscan times, there were two primary settlements of the embryonic ‘Rome’, one on the Palatine Hill and the other on the Quirinal, which were closely bonded. The Sabinic tribe extended towards the Viminal hill and the Latin tribe expanded to the Velia (east of the Forum), on the Subura and in the Etruscan times on the Janiculum, towards the right bank of the Tiber.
In Etruscan times the Quirinal became the central point of the emerging city, but after the autonomy of Rome in the fifth century BC, the eastern and southern suburbs were incorporated in the city, making up three different parts. After the invasion of the Gaul (in 390 BC), it became clear that the protection of the acropolis was insufficient. At the beginning of the fourth century and the establishment of the republic, the Palatine Hill was included in the still-expanding city, which now consisted of four parts (VON GERKAN, 1959). The ‘Urbs quattuor regionum’ became a historical entity (fig. 99). The characterization of Rome as a ‘city-on-seven-hills’ might have some topographic references, but was never used in an administrative sense. The ‘Septimontium‘, described by Varro (116 – 27 BC) in his ‘De Lingua Latina’ (6, 24), was the name for a celebration, which took place in Rome, but it cannot be shown that the ‘Septimontium‘ had any connection with the division of the town in any part of its development.
Fig. 99 – A map of the Rome in Servianian times, when the city was divided in four districts, the ‘Urbs quattuor regionum’. The main topographic features and the boundaries of the areas with the same name are indicated: I: Suburana; II: Esquilina; III. Collina; IV: Palatina. According to Von GERKAN (1959).
The actual character of the four-parted Rome and its precise boundaries are a matter of scientific debate. MÜLLER (1961) gives four types of division of the regions in Rome (fig. 100). After its initial two-part development the unity of Rome was moulded from four districts or sectors of which MÜLLER (1961) said: ‘Vier Sektoren: Der Gedanke an ‘Roma quadrata’ drängt sich auf, was richtigerweise wohl mit ‘viergeteiltes Rom’ anstelle von ‘quadratisches Rom’ übersetzt werden muss’.
Fig. 100 – The four regions in Rome, according to Kiepert (1837), Richter (1901), Hülsen (1901) and von Gerkan (1953).
Since the establishment of Rome on the Palatine Hill, there never was a square form in its (natural) design. The Greek biographer Plutarch (46? – 120? AD;) described – in his ‘Romulus‘ (11) – the genesis of Rome as a circle-shaped plan with four gates. Representations of the city of Rome in a square form were based on fantasy.
The Ravenna-born Fabio Calvo planned a pictorial reconstruction of ancient Rome together with the painter Raphael. The death of the latter (in 1520) prevented this plan. Calvo described in his book ‘Antiquae Urbis Romae cum regionibus simulacrum‘ (Rome, 1527) a whole series of (fantasy) drawings in which the city of Rome is respectively round, square (fig. 101) and with eighth- and sixteenth corners (BENEVOLO, 1980). The different geometrical forms relate, in Calvo’s view, to the subsequent periods of government in the history of the city. They were derived from a Renaissance mind, who tried to establish some preconceptual ideas about geometry and division thinking in the features of the past.
Fig. 101 – Fantasy representation of ‘Quadrata Roma’ at the time of the founding of the city by Romulus (eight century B.C.). Part of a series of different geometrical shapes of Rome in the ‘Antiquae Urbis Romae cum regionibus simulacrum’ by Fabio Calvo, published in Rome in 1527. In: BENEVOLO (1980).
EHRHARDT (1945, p. 182) pointed, in a most instructive article, to the cosmological implications of a city building plan: ‘The ideal city is built in a square, or at least its roads meet in right angles, in order to express the fact that the political system, likewise, derives its rules from the spiritual form of the cosmos’.
The square shape is associated with the Greek term ‘dikaiosyne‘, pointing to a divine justice, which in turn, is closely connected with the number four. The ‘dikaiosyne‘ is the first of the four cardinal virtues and generates the bond between the divine macro- and the human micro-cosmos (not unlike the quadralectic relation between First and Third Quadrant). There is a ‘quadrata iustitia’ and a healthy body is called a ‘quadratum corpus’. A good character is a ‘signum quadratum‘ (from the Greek ‘kallokagathos’).
In the Greek sculptural art these geometric implications were elaborated by Polykleitos in his ‘Canon’. This title means literally a ‘ruler’. It indicated a scheme of proportions, which had to be the base of every piece of art to comply with to the pursuit of beauty (to kallon). Beauty, in Polykleitos’ view, is the conscious perception of relations (s’ JACOB, 1987). The ideal proportions of the human body consist of four parts: from the feet to the knee, from the knee to the crutch, from the crutch to the armpits and from the armpits to the crown. A person built in this way is a ‘tetragonos aner’.
The Romans adopted these Greek notions in a practical sense in their town planning. They followed the fifth-century BC Greek architect Hippodamus, son of Euryphon of Miletus, who built cities according to the ‘Hippodamian principles’, i.e. as a grid. The cities of Olythus, southeast of Thessaloniki, and Priene, in the valley of the Meander, were outstanding examples of the Greek grid towns. The Roman town builders copied the grid system, but they started with a cross-shape, which was ‘filled up’ to a grid (fig. 102).
Fig. 102 – The city plan of Timgad in Numidia (Algeria) is a good example of a Roman settlement, based on a regular pattern. The main axis, called ‘decumus maximus‘ and ‘kardo maximus‘, were first laid out as a cross. The city-square and the amphitheater were positioned along the southern part of the kardo maximus. The buildings were, in this particular case, organized in four blocs (5 x 6 and 6 x 6), to make up an extended ‘centurio‘. After: VON GERKAN (1939). Kolonial-städte der Antike.
The Roman land surveying started with the positioning of a ‘groma’, a measure apparatus with a ‘tetrans’ and ‘stella‘ as a cross-shaped sight. The location of the groma was in the centre of the area in which building was planned. Two lines were surveyed from this central point: the shadow of the sun provided the north-south axis, the ‘kardo‘. The so-called ‘decumanus‘ was drawn perpendicular on this line, resulting in a cross as a frame of reference. The major axes (being the initial main streets) were denominated the ‘kardo maximus’ (KM) and the ‘decumanus maximus’ (DM) (DILKE, 1971; 1987) (fig. 103).
Fig. 103 – This illustration of the main pivots in a building project was given in a mediaeval manual for Roman surveyors. The original books from the first to the fourth century BC were copied in the Middle Ages, but the art to draw maps to scale was lost. The diagram shows the base lines in a square: DM = decumanus maximus (E – W) and KM = kardo maximus (N – S).
At the end of the main streets four gates were built and the quadrants were further divided in twenty-five blocks (or ‘centuriae‘) each (fig. 104): ‘Ab uno umbilico in quattuor partes omnis centuriarum ordo componitur‘. This method of surveying was also frequently used in the ‘castrametation‘, the military practice, when a (temporary) army camp had to be set up.
Fig. 104 – The theoretical base of Roman surveying consisted of two axes, four quadrants and hundred squares: ‘Ab uni umbilico in quattuor partes omnis centuriarum ordo componitur‘. The four-partitioning of space was a fundamental feature in Roman geodesy, often used in military practice to put up camp, and in a more elaborate form, in subsequent town planning.
An example can be found in the square outlines of several army-camps used by the siege of Masada (Israël), the Jewish mountain-fortress, in 73 AD – ending with the collective suicide of nine hundred and sixty defenders (YADIN, 1966). The names of the main streets were not ‘via kardinalis‘ and ‘via decumana‘ in military practice, as to be expected, but ‘via principalis‘ and ‘via praetoria‘.
There are many examples of the influence of the Roman ‘agrimensores‘ in city development (BENEVOLO, 1980): Aosta (in Italy), Cologne and Trier (Germany) and Silchester in England (fig. 81 right). More examples can be found, in particular, in the newly conquered areas during the expansion of the Roman empire. However, not every cross-shaped street-plan is of ‘Roman’ origin. Many demographic developments took place after the Romans had gone. The importance of a town or city in the Middle Ages, and its subsequent expansion, depended often on its geographical position on crossroads between areas of (early) economic activity.
Vitruvius’ book on architecture – published by Cesare Cesariano in Como, 1521 – gave a scheme of the theoretical division of a Roman town in ‘insulae‘ (fig. 105 left, from the edition of 1536). The city of Silchester (England) is one of the many examples of settlements with their Roman roots still visible (fig. 105 right). These two illustrations of a theoretical design and a practical appearance of a Roman town indicate also the flexibility of Roman engineering.
Fig. 105 – Left: From Vitruvius’ book ‘De Architectura‘ (edition 1536). The Italian Renaissance showed a great interest in geometrical compositions as part of the pursuit of clarity in architecture and sculpture. Right: The Roman city of Silchester in England. The grid-work of ‘insulae‘ around the central ‘Forum‘ is clearly visible on this map of the excavation area. The transition from a well-designed army camp into a small town, which was best observed at the geographical borders of the Roman Empire during its greatest extension, was often a gradual one.
There is substantial evidence for division-thinking in architecture in the later centuries of the Roman Empire. The subject is, as far as known, never studied from this particular angle. The great building activities of the Roman emperors Trajan (98 – 117) and Hadrian (117 – 138), in particular, demonstrate an explicit concern with a functional division in their design. The principle of two-side symmetry (related to dual thinking) is most prominent, but there is also evidence of the four-fold division. The question of a numerological origin or a genuine application of a form of tetradic thinking in the ‘Hadrian architecture’ will be a subject of further study.
Building became an expression of power. It was a time of architectural innovations. WHITE (1984) said: ‘By the first century AD builders had discovered that two vaults could be made to intersect at right angles without any danger to the stability of either. Such ‘groined’ vaults could be used to roof a large rectangular space, the roof supported by piers at each of the four points of intersection. Once this scheme had been put into practice, it was a simple matter for the architect to minister to the expanding tastes of emperors obsessed with notions of size and splendour by multiplying the number of intersecting elements, creating such vast and imposing structures as the Bath of Caracalla or the Basilica of Maxentius.’
The well-known Pantheon in Rome, completed during the reign of emperor Hadrian, exhibit the ultimate possibilities of the new construction methods and materials (brickwork) and can be seen as a highlight of division-thinking in practice (MACDONALD, 1976)(fig. 106).
Fig. 106 – The Pantheon in Rome. The building was founded by Marcus Agrippa, the son-in-law of Augustus, in 27 AD. After a fire it was rebuilt by Hadrian between 118 and 128 AD. The building is a symbiosis of linear and cyclic thinking, aiming at the ultimate architectural representation of (double-four) division-thinking. Ground plan by F. Coarelli.
Hadrian’s palace in Tivoli near Rome and the baths at Lepcis Magna in Libya (fig. 107) gave further evidence of a well-developed consciousness of division-thinking translated into architectonic visibility.
Fig. 107 – The baths of the Roman Emperor Hadrian at Lepcis Magna in Libya (126/127 AD) show a bilateral symmetry along a vertical and is divided in four parts in a horizontal plan. The four main areas are, from top to bottom: 1 (a). natatio (swimming pool); 2 (b/c). frigidarium (cold bath); 3 (e). tepidarium (lukewarm bath); 4. (f) calidarium (hot bath).
Hundred years later the bath of Caracalla (212 – 216 AD) used the same four-fold scheme (fig. 108/109). A strong bilateral symmetry is prominent, but also the four different types of baths along the vertical axis provide their own, symbolic meaning. The round ‘calidarium‘ (C), the ‘tepidarium‘ (T), ‘frigidarium‘ (F, with four water basins in the corners) and the ‘natatio’ (N) are stages in a process of mental and bodily cleaning. In the lateral buildings, like the change-rooms (A, apodyterien) and the areas for exercise (B, the ‘palaistra‘), the strict division-order is loosened.
Fig. 108 – The ground plan of the baths of Emperor Caracalla (M. Aurelius Antoninus) or ‘Thermae Antoniniae‘. The complex was built between 212 and 216 AD along the Via Nova in Rome and measured 220 x 114 meters. These baths are one of the best preserved and prominent features of Roman architecture.
Fig. 109 – Part of the Bath of Caracalla in Rome (212 – 216 AD). Photo: Marten Kuilman (2000).
Emperor Diocletian (298 – 305 AD) constructed, nearly another century later, the biggest bath complex in Rome: 376 x 361 meters with a three-partion (calidario, tepidario and frigidario) of the bath-section. Instead of a ‘natatio‘ there was a walled area around the whole complex, providing an area for preparation, and making up the four-division, which is so typical for the older baths.
Further variations on the same theme of bilateral symmetry and four-fold division can be found in the Roman baths at Badenweiller (Blackforest, Germany) (PÖRTNER & TADEMA SPORRY, 1959/1976) and the bathing complex in Trier (Germany) (WEITZMANN, 1979) (fig. 110).
Fig. 110 – A plan of the Imperial Baths in Trier (Germany) shows the symmetrical lay-out and an elaborate development of the four-fold scheme of Caldarium (C), Tepidarium (T), Frigidarium (F) and Natatio (N). The Imperial Baths were one of three bath houses in Trier (Augusta Treverorum) and constructed during the reign of Constantine the Great (306 – 337 AD). Only the eastern side has survived as a ruin. The external masonry, with alternating blocks and brickwork, is of architectural importance. In: WEITZMANN (1979). A plan of the Imperial Thermae in Trier is also given (p. 300) in: FLETCHER (1975).
The triumphal arch is a distinct, but somewhat confusing type of architectural evidence with regards to division-thinking. This particular type of arch is closely related to the folly, a building without a function except to satisfy the vanity of its builder. The basic pattern is a framework of four pillars. It can be integrated in a wall with either one – like the triumphal arch of Titus on the Velia, erected in 81 AD – or three passages – of which the arch of Septimus Severus (203 AD), on the north-side of the Forum in Rome, is most characteristic.
The style reflects the straight-forward way of thinking of the emperors, who had these extravagances erected. Battle scenes were the favorite subject on the reliefs placed on the inner and outer walls of the arch. As such they are monuments for the power-motivated and strife-orientated way of thinking, which is typical for the empirical Third Quadrant (in a quadralectic visibility-cycle). Two- and three-fold division is of prime importance, but in later developments the four-fold division had an ambivalent role.
The fore-mentioned emperor Septimus Severus had a four-parted arch (or ‘tetrapylon‘) erected in Lepcis Magna (in Libya, fig. 111) at more or less the same time as the ‘classical’ arch with three passages in Rome. The four monumental reliefs on the inside of the arches were transferred to the museum of Tripoli.
Fig. 111 – The triumphal arch (tetrapylon) of Septimus Severus (200 – 210 AD) at Lepcis Magna (Libya). This four-fold design is a further development in the history of triumphal arches. Their three-fold origin is firmly embedded in the power-thoughts of the Flavian emperors. In: GIEDION (1969).
An arch of Janus or ‘Janus quadrifrons‘ was erected on the Forum Boarium (cattle market) of Rome in the second half of the fourth century, during the reign of Constantine I (the Great) (fig. 112). It was glorified in its decay by Giovanni Battista Piranesi, who made a great number of copper-etchings of the classical buildings of Rom at the end of the eighteenth century in his ‘Vedute di Roma‘. This arch, built from marble and covered with brick (now disappeared) was called ‘Janus Quirini‘ and dedicated to the war god Quirinus, another disguise of Mars. The structure had four large entrances (GIEDION, 1969).
Fig. 112 – The ‘Arcus Quadrifons‘ or ‘Ianus Quadrifrons‘ – a tetrapylon – is seen here on the Forum Boarium near the River Tiber in Rome. Giovanni Battista Piranesi made a copper etching of the arch in 1771. Photo: Marten Kuilman (2000).
The four-fold division was popular as a symbolic entity at the end of the third century AD. This emblematic awareness was expressed in architecture, but also in sculpture and even in politics. The quadriga, as a metaphorical carriage, was a popular artistic motif, expressing the powerful aspects of the four-fold. Emperor Diocletian (emperor from 284 – 305 AD) introduced a type of political system, the so-called tetrarchy, based on the division of political powers in four geographical units. Diocletian and Maximianus – with the titles of ‘Augustus‘ – ruled in respectively the east and west-side of the empire. Constantius Chlorus and Galerius – titled ‘Caesar‘ – were their co-rulers (KOLB, 1987).
Sextus Aurelius Victor, a Latin historian around 360 AD, remarked that all rulers of the First Tetrarchy came from the area of Illyrium and showed a lack of ‘humanitas‘. The (first) tetrarchy collapsed in a power struggle and dead: Maximianus resigned in 305 AD, but had himself reinstated during the reign of his son Maxentius in 306 and later committed suicide. Constantius Chlorus died in 306 and Galerius died in 311.
Only Emperor Diocletian survived his own political system and retreated voluntarily in 305 AD to live in Illyria, his country of birth. He built an enormous castle with a strong tetradic outlay in Spalato (Split), on the coast of the Adriatic Sea. Diocletian died in 311. His mausoleum, in the enclosure of the castle, has an octagonal shape (fig. 113).
Fig. 113 – Top: Reconstruction of the palace of Diocletian in Split. The extended building was erected in the fourth century A.D. and used by the emperor in his retirement. The design of the palace followed the standard Roman surveying techniques, with two crossing main streets, the ‘decumanus maximus‘ (DM) and the ‘kardo maximus‘ (KM). Below: The mausoleum of Diocletian, build within the palace, had an octagonal base.
The most prolific treatment of the fourfold division can be found in Roman poetry. The Roman poet Quintus Ennius (239 – 169 BC) was strongly influenced by the Greek classical authors. He introduced the Greek hexameter in Rome and spoke three languages, a ‘vir trilinguis‘. In 204 BC – during the Second Punic War – he was a centurion in the Roman army and later became a teacher (in the Greek language) in Rome.
Ennius was instrumental in the introduction of Empedocles’ four-fold cycle of creation in the Roman culture (the so-called ‘paluda virago‘-fragment: Empedocles 17 = Ennius 522; OOSTENBROEK, 1977). He also knew the Greek playwright Euripides (c. 480 – 406 BC), author of tragedies like ‘Alcestis‘ (last piece of a tetralogy) and the ‘Medea‘. These plays dealt with philosophical, religious and political themes. Euripides was influenced by Archelaos, a follower of Empedocles.
RAMSAY (1927) indicated the ‘Asiatic’ element in the Greek-European way of thinking. He staged the four Ionic tribes (chapter XVII) and concluded: ‘In Ionia (the Greek colony in western Turkey), in European Greece, on the Anatolian plateau, and in India we must suppose that there did exist once a social state which was adapted to the fourfold way of life.’
Euripides described the four sons of Ion as the leaders of different tribes (or phylae). ‘Four tribes’, according to RAMSAY (1927), ‘indubitably Asian in origin’: Geleontes (or Gedeontes), Aigikoreis, Argadeis (or Ergadeis) and Hopletes. Furthermore, Aristotle (in the ‘Politeia‘, ch. 41) mentioned this division, which was later (for instance by Strabo) associated with specific tasks and functions.
Even more important for the incorporation of the tetradic thoughts in the Roman cultural period was the poem called ‘Georgica‘ by Vergilius. The writer, Publius Vergilius Maro, was born in 70 BC at Mantua and reached great fame during his life (GRIFFIN, 1986). His first ‘bucolic’ or pastoral poems, titled the ‘Eclogues‘, dated from around 40 BC. Vergilius proclaimed to follow the tradition of the poet Theocritus, a Greek from Syracuse, who wrote pastoral poetry around 280 – 260 BC. Around 29 BC followed the ‘Georgica‘ (circa two thousand lines), using Hesiod of Ascra’s’ ‘Works and Days’ as an example. And finally the ‘Aeneid‘, unfinished at his death in 19 BC, consisting of circa ten thousand lines. Here the story of the ‘Iliad‘ and ‘Odyssee‘ of Homer were reduced to twelve books.
Vergilius’ ‘Georgica‘ is a tetradic epos. The first book is written in the style of the ‘Works and Days‘ (ROSS, 1987). The relation between heaven and earth is a mediator and there is a strict discipline enforced. In the second book, the emphasis is on the life of plants in relation to the soil and growth. A mythic-magical element is interwoven in the text. The third book deals with reality: animals, sexuality and death are the themes. The continuity of the name is safeguarded. The fourth book discussed the physical force and mental understanding, or the highest aims in human life. The first and the third book start with a long introduction and end with death and disaster. The second and the fourth book have a short prelude and come to an end with a song of praise or an enchanting story (PUTNAM, 1979).
This presentation echoed Empedocles’ cycle of love and strife: the arcadic and static first position (of love) is followed by the vigorous growth and development (with strife) in the second location. The development crystallizes in a static reality and identity (of love) in the third setting and turns into the highest, dynamic aims and understanding in the fourth quarter (in strife).
Finally, the poet Ovidius (43 B.C. – c. 17 A.D.), in his ‘Metamorphoses‘, did a great deal to record the old (Greek) mythological stories. The book starts in a fourfold mood with the creation-story of the earth. First, there is a two-division from a shapeless uncoordinated mass (Chaos) in strife to a separation by a god into elements, forming a harmonious union.
This episode is followed by the creation of man – either by a Creator, or else Prometheus, son of Iapetus. A summary of human history is given in four parts, which is a modification of Empedocles’ cycle of Love and Strife. The Golden Age (of unbound happiness) was followed by the Age of Silver with the institution of the cycle of four seasons and agricultural labour. Then came the Age of Bronze with a fiercer character, but still free from wickedness and finally the Age of Iron, without modesty, truth and loyalty. Book II of the ‘Metamorphoses‘ begins with Phaeton in his quadriga with the horses Pyroïs, Eoüs, Aethon and Phlegon. The last book deals with the teachings of Pythagoras, including the ‘Four Ages of Man’ (Bk XV: 199 – 236).
Theme from Ovid’s Metamorphoses. ‘At the top of the sheet, Jupiter sits on his eagle and hurls a thunderbolt at Phaethon, son of Apollo, who plunges from a horse-drawn chariot. Phaethon had asked to drive the chariot of the sun, but he lost control and to save the earth Jupiter destroyed him. Underneath, his sisters, the weeping Heliades, are changed into poplar trees while another relation, Cycnus, has become a swan. The reclining male figure is the river god, Eridanus into whose river (the River Po in Italy) Phaethon fell. At the very bottom is a message in Michelangelo’s handwriting addressed to the recipient of this ‘presentation drawing’, the young Florentine nobleman, Tommaso Cavalieri. The message states that if Cavalieri does not like this unfinished drawing, Michelangelo will draw another the next evening or, if he does, the artist will finish it. As the drawing is finished, Tommaso must have liked it. The specific meaning of the composition for both Michelangelo and Cavalieri is not known. On a general level, it may refer to the dangers of pride as a moral warning from an older man to a youth. Michelangelo also drew a lost portrait of Tommaso and gave him several other ‘presentation drawings’ with allegorical and narrative themes. The creation of such works reflects the growing appreciation in the Renaissance for the intimate medium of drawing, particularly those created by the most advanced artists of the period’. (www.britishmuseum.org). Michelangelo, Royal Library Windsor. HETZER (1987).
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