by Unknown
3 Lynne Lancaster, “The Lightweight Volcanic Scoria in the Concrete Vaults of Imperial Rome: Some Evidence for the Trade and Economy of Building Materials,” Proceedings of the XVIth International Congress of Classical Archaeology, Boston, 2003: pp. 212–216. Cf. Lancaster 2005, p. 64. Pumice is used in general literature to refer to both red-to-brown scoria of the type used in the Pantheon (750–850 kg/m3) and dark-light gray pumice (600–700 kg/m3), which tended to be used in the late third and fourth centuries.
4 Alberto Terenzio, “La Restauration du Panthéon de Rome,” Museion 20, 1932, pp. 52–57; on p. 52 he promised a detailed publication of his findings relating to the restoration works of 1930–1931, but this resource remains unpublished.
5 Rowland J. Mainstone, Development in Structural Form, London 1975, pp. 116–117; Robert Mark and Paul Hutchinson, “The Structure of the Roman Pantheon,” Art Bulletin 78, 1986, pp. 24–34; Robert Mark, Light, Wind, and Structure, Cambridge 1990, p. 60 ff.; David Moore, The Roman Pantheon: The Triumph of Concrete, Wyoming 1995, p. 2; Jacques Heyman, “Poleni’s Problem,” Proceedings of the Institution of Civil Engineers 1, no. 84, 1988, pp. 737–759.
6 Giorgio Croci, The Conservation and Structural Restoration of Architectural Heritage, Boston 1998, p. 125; Croci, “Il comportamento strutturale del Pantheon,” in Giovanni Belardi, Il Pantheon: storia, tecnica, e restauro, Viterbo 2006, pp. 263–310, esp. 266–267, 282–283, 285–287. Cf. Kjeld De Fine Licht, The Rotunda in Rome: A Study of Hadrian’s Pantheon, Copenhagen 1968, pp. 89–93.
7 Differential settlement affected Agrippa’s Pantheon to a greater extent, to judge by sloping levels observable in the foundations that survive under the portico of the existing building; see Chapter Two.
8 That the cracking occurred during or soon after construction is suggested by the use of bricks of similar date to those in the rest of the Pantheon for repairing and filling the cracks; see Licht 1968, p. 288, n. 40. Giuseppe Cozzo (Ingegneria Romana: maestranze romane; strutture preromane, strutture romane, le costruzioni dell’anfiteatro flavio, del Pantheon, dell’emissario del Fucino, Rome 1928) made much of the structural problems affecting the southern sector of the rotunda, although his interpretation is fantastical. Alberto Terenzio, s.v. “Pantheon,” Enciclopedia Italiana 26, 1949, pp. 212–214; p. 213 uses the term accidentata to characterize the progress of the works; cf. Terenzio 1932, p. 54. See also Moore 1995, 11–13.
9 On Roman concrete, see Adam 1984 (1994 translation), pp. 73–79, 177–91; Heinz-Otto Lamprecht, Opus Caementitium. Bautechnik der Römer, Düsseldorf 1987; Moore 1995; G. R. H. Wright, Ancient Building Technology, vol. 2: Materials, part 1, Boston 2005, Chap. 6; Lancaster 2005, esp. Chap. 3.
10 S. Huerta, Arcos, bóvedas y cúpulas. Geometria y equilibrio en el cálculo tradicional de estructuras de fábrica, Madrid 2004.
11 William L. MacDonald, The Pantheon: Design, Meaning, and Progeny, London 1976, p. 38.
12 Eugène-Emmanuel Viollet-le-Duc, s.v. “Voute,” Dictionnaire raisonné de l’architecture française du XIe au XVIe siècle, vol. 9, Paris 1875, pp. 471–474, with Fig. B on p. 475; Taylor 2003, pp. 194–211; cf. Adam 1984, Fig. 443. Taylor assigns a major role to ropes, but these would stretch variably according to humidity and temperature and so perhaps not be capable of providing dimensional stability.
13 I thank Dina D’Ayala for generously lending her engineering expertise to vet initial proposals.
14 The structural behavior is composite in nature, meaning that part of the load was resisted by the lower part of the dome (once the concrete had hardened sufficiently).
15 For opinion favoring some kind of central timber tower, see Jürgen Rasch, “Zur Konstruktion spätantiker Kuppeln vom 3 bis 6 Jahrhundert,” Jahrbuch des deutsches Archäologischen Instituts 106, 1991, pp. 311–383; pp. 369–370; Gerd Heene, Baustelle Pantheon: Plannung, Konstruktion; Logistik, Düsseldorf 2004; Lancaster 2005, pp. 44–45.
16 Adriano La Regina, ed., L’arte dell’assedio di Apollodoro di Damasco, Rome 1999.
17 Relieving arches could provide support for higher levels to be initiated without the fabric of the walls enclosed by the arches, this following on later, as convenient. For further discussion, see Heene 2004; Lancaster 2005, pp. 94–95; and Chapter Four in this volume.
18 Terenzio 1932, 54; J. Guey, “Devrai-on dire: Le Panthéon de Septime Sévère? A propos des estampilles sur briques recueillies dans ce monument, notamment en 1930 ou en 1931 et depuis,” Mélanges d’Archéologie et d’Histoire (Ecole Française de Rome) 53, 1936, pp. 198–249; p. 237, n.5. For the complex as a whole, see Licht 1968, 157–171. For a proposal that the grottoni could have been used as archival storage, see Amanda Claridge, “Hadrian’s Lost Temple of Trajan,” Journal of Roman Archaeology 20, 2007, esp. p. 79.
19 Licht 1968, p. 163, Fig. 179.
20 Cozzo 1928, pp. 283–285.
21 Rita Volpe, “Un antico giornale di cantiere delle terme di Traiano,” Mitteilungen des Deutschen Archäologischen Instituts, Römische Abteilung 109, 2002, pp. 377–394.
22 Today the crack may be inspected on the second level of the grottoni. Its presence at floor level, though now covered over, is attested by photographs, including one in the Archivio Fotografico, Soprintendenza per i Beni Architettonici e per il Paesaggio di Roma, neg. 2967.
23 For a reasoned summary of preceding opinion, see Licht 1968, pp. 85–88.
24 For Leclère’s survey, see Roma antiqua. “Envois” degli architetti francesi (1786–1901), Grandi edifici pubblici, exhib. cat., Rome 1992, pp. 100–123.
25 I am grateful to many for their kind help with this project: to Giovanni Belardi, the director responsible for the Pantheon of the Soprintendenza per i Beni Architettonici e per il Paesaggio di Roma, for permission; to Cinzia Conti and her students Roberta Zaccara, Tomaso De Pasquale, and Mariangela Perrota for surveying; to Robert Grover for drawing up the results; to Cinzia Conti and Giangiacomo Martines for precious observations in loco.
26 Here, I find myself conscious of a debt to Giovanni Belardi for authorization to study the stairs, yet we disagree over interpretation. He believes the rotunda to precede the transitional block, but to me, the saggio disproves this.
27 Such is the similarity in technique between the upper and lower halves of the staircase in general that their construction may have been supervised by the same people, as remarked to me by Cinzia Conti.
28 Antonio Maria Colini and Italo Gismondi, “Contributo allo studio del Pantheon: La parte frontale dell’avancorpo e la data del portico,” Bullettino della Commissione Archeologica Comunale di Roma 44, 1926, pp. 67–92; especially 83, 87–92; they did not, however, set out sufficient evidence to resolve the question definitively. Luca Beltrami, Il Pantheon: La struttura organica della cupola e del sottostante tamburo, le fondazioni della rotonda, dell’ avancorpo, e del portico, avanzi degli edifici anteriori alle costruzioni adrianee. Relazione delle indagini eseguite dal R. Ministero della Pubblica Istruzione negli anni 1892–83, coi rilievi e disegni dell’ architetto Pier Olinto Armanini, Milan 1898, pp. 41–46; Cozzo 1928, pp. 281–282, Fig. 192; Licht 1968, pp. 59–63, 189; Mark Wilson Jones, “The Pantheon and the Phasing of its Construction,” in Gerd Grasshoff, Michael Heinzelmann, and Markus Wäfler, eds., The Pantheon in Rome: Contributions to the Conference, Bern, November 9–12, 2006, Bern 2009, pp. 69–87, Fig. 13.
29 Colini and Gismondi 1926, pp. 70–73. Leclère’s earlier inspections had led him to conclude that the transitional block cannot have been added in a separate phase, and in particular that there did not exist an earlier Pantheon with its front formed by the avancorpo alone, as Carlo Fontana had proposed. If Fontana were right, the horizontal cornice of the upper pediment would once have continued right across the face of the building, but there is no sign of such.
30 Colini and Gismondi 1926, pp. 75–77. Colini speculated that the inclined bipedales would originally have projected slightly beyond the face of the wall so as to resist rainwater ingress at the junction with th
e roof. Unfortunately, the area where these bipedales would be was covered by a metal flashing during the refurbishment of the roof covering in the autumn of 2010 before my own visit.
31 Tilmann Buddensieg, “Criticism and Praise of the Pantheon in the Middle Ages and the Renaissance,” Classical Influences on European Culture A.D. 500–1500: Proceedings of an International Conference Held at Kings College, Cambridge, April 1969, ed. R. R. Bolgar, Cambridge 1971, pp. 259–267; Paul Davies, David Hemsoll, and Mark Wilson Jones, “The Pantheon: Triumph of Rome or Triumph of Compromise?” Art History, 10, 1987, pp. 133–153; Tod A. Marder, “Bernini and Alexander VII: Criticism and Praise of the Pantheon in the Seventeenth Century,” Art Bulletin 71, 1989 pp. 628–645; Susanna Pasquali, Il Pantheon: architettura e antiquaria nel Settecento a Roma, Modena, 1996, Chaps. 5 and 6; Mark Wilson Jones, Principles of Roman Architecture, New Haven 2000, pp. 187–191, 199–202.
32 Wilson Jones 2000, pp. 191–196.
33 Heinz Kähler, “Das Pantheon in Rom,” Meilensteine europäischer Kunst, ed. E. Steingräber, Munich 1965, pp. 45–75; pp. 58–65; Marder 1989; William C. Loerke, “A Rereading of the Interior Elevation of Hadrian’s Rotunda,” Journal of the Society of Architectural Historians 49, 1990, pp. 32–43, esp. p. 30 ff.; Wilson Jones 2000, pp. 191–196. Cf. MacDonald 1976, pp. 70–72.
34 Adapted from Giorgio Vasari, The Lives of the Painters, Sculptors, and Architects, Florence 1550, trans. A. B. Hinds, repr. London 1963, pp. 275–276. A seventeenth-century source (Cod.Barb.Lat. 4309, f.11v) also attributed to Michelangelo the judgment that the first of the three phases was so good as to be “the product of angels,” which implies that the other phases were not so good. Cf. Buddensieg 1971, p. 265.
35 Cozzo 1928. For a critique of Cozzo’s theories in relation to brickstamps, see Herbert Bloch, “I bolli laterizi e la storia edilizia romana,” Bullettino della Commissione Archeologica Comunale di Roma 64, 1937–1938; Bloch, I bolli laterizi e la storia edilizia romana. Contributi all’archeologia e alla storia romana (1936–1938), Rome 1947. A variant of Cozzo’s (and Carlo Fea’s) ideas on the Pantheon continues to be championed in Giovanni Belardi 2006. Gene Waddell (Creating the Pantheon: Design, Materials, and Construction, Rome 2008, esp. pp. 124–138, 149–150) advocates a substantial Severan restoration of the portico, but too substantial in my view.
36 On these inscriptions and their interpretation, see Adam Ziolkowski, “Prolegomena to Any Future Methaphysics [sic] on Agrippa’s Pantheon,” in “Res bene gestae”: Ricerche di storia urbana su Roma antica in onore di Eva Margareta Steinby, ed. A. Leone, D. Palombi, and S. Walker, Rome 2007, pp. 465–475, esp. 466–468; Ziolkowski, “What Did Agrippa’s Pantheon Look Like? New Answers to an Old Question,” in Grasshoff, Heinzelmann, and Wäfler 2009, pp. 29–39, esp. 38–39; C. Simpson, “The Pantheon’s Inscription, CIL 6.896: Its Date of Composition, Cultural Context, and ‘Message,’” Athenaeum 97, 2009, pp. 149–157; Mary T. Boatwright, “Hadrian and the Agrippa Inscription of the Pantheon,” Hadrian: Art, Politics and Economy, ed. Thorsten Opper, British Museum Research Publications 175, London 2013, pp. 19–30.
37 It has been pointed out, for example, that that even if the junction of rotunda and portico might be judged unsatisfactory, this could not be seen in antiquity from the forum-like “forecourt,” not forgetting that the ground level was at least two meters lower than at present. See MacDonald 1982, pp. 111–113; cf. Wilson Jones 2000, p. 202.
38 The key proportional rule for the Corinthian order set the height of the shaft as 5/6 that of the complete column (including base and capital), and so 50-foot shafts imply columns 60 feet tall; both dimensions harmonize well with 75- and 150-foot measures elsewhere in the whole project. For the design of the Corinthian column, see Wilson Jones, “Designing the Roman Corinthian Order,” Journal of Roman Archaeology 2, 1989, pp. 35–69; Wilson Jones 2000, Chap. 7.
39 Davies, Hemsoll, and Wilson Jones 1987; Wilson Jones 2000, Ch. 10. For shipwrecked cargoes of ancient marbles see P. Pensabene, Il fenomeno del marmo nel mondo romano, in I marmi colorati della Roma imperiale, Rome 2002, pp. 3–67, esp. 34–46. Alternatively, Claridge (2007, p. 94) advances a plausible scenario by which the 50-foot shafts were diverted to the Temple of Trajan. Supplies of such huge stones were evidently inadequate for both projects within acceptable timescales.
40 Wilson Jones 2000, p. 148, p. 155, and Appendix B; Pensabene 2002, pp. 24–25; Paolo Barresi, “Il ruolo delle colonne nel costo degli edifici pubblici,” in I marmi colorati della Roma imperiale, ed. Marilda De Nuccio and Lucrezia Ungaro, Rome 2002, pp. 69–81. This last study puts emphasis on multiples of 4 ft. It is true that the popular sizes of 16, 20, 24, and 40 ft are multiples of 4 ft, but since 20 and 40 ft are multiples of 5 ft as well, and since 5 ft also divides into the other popular sizes of 15, 25, 30, and 50 ft, it is best to speak of multiples of 4 and/or 5 ft, with 5 ft being the dominant of the two.
41 Wilson Jones 2000, p. 203.
42 Theodore Peña, “P. Giss. 69: Evidence for the Supplying of Stone Transport Operations in Roman Egypt and the Production of Fifty-Foot Monolithic Column Shafts,” Journal of Roman Archaeology 2, 1989, pp. 126–132, esp. p. 131; Richard Tomlinson, From Mycenae to Constantinople. The Evolution of the Ancient City, London 1992, p. 163; Jürgen J. Rasch, Das Mausoleum bei Tor de’ Schiavi in Rom, Mainz 1993, p. 54, n. 331; Edmund Thomas, “The Architectural History of the Pantheon in Rome from Agrippa to Septimus Severus via Hadrian,” Hephaistos 15, 1997, pp. 163–186; esp. 179–180; Adam Ziolkowski, s.v.“Pantheon” in E. M. Steinby, Lexicon Topographicum Urbis Romae, 5 vols., 1995–1999; vol. 4, 1999, p. 58; Fikret Yegül, review of Wilson Jones 2000, Journal of the Society of Architectural Historians 60, 2001, pp. 500–504; Paolo Barresi, review of Wilson Jones 2000, Archeologia Classica 53, 2002, pp. 593–598; James Packer, review of Wilson Jones 2000, American Journal of Archaeology 106, no. 2, 2002, pp. 344–345; Thomas N. Howe, review of Wilson Jones 2000, Bryn Mawr Classical Review, April 15, 2002, pp. 469–472, http://ccat.sas.upenn.edu/bmcr/; Alessandro Viscogliosi, “Il Pantheon e Apollodoro di Damasco,” Tra Damasco e Roma: L’architettura di Apollodoro nella cultura classica, ed. Festa Farina et al., Rome 2001, pp. 156–161, esp. p. 159; Taylor 2003, pp. 129–132; Rabun Taylor, “Hadrian’s Serapeum in Rome,” American Journal of Archaeology 108, 2004, pp. 223–266, esp. 244–254 (with a different proposal for the cause); Heene 2004; Eugenio La Rocca, “Templum Traiani et columna cochlis,” Mitteilungen des Deutschen Archäologischen Instituts, Römische Abteilung 111, 2004, pp. 193–238; p. 211. Waddell (2008, esp. p. 135) accepts the change of column size, but thinks settlement prompted a Severan rebuilding of the portico. For a more neutral reception (noting the hypothesis with caution), see Martin Maischberger, Marmor in Rom, Ph.D. diss., Freie Universität, Berlin 1997, pp. 145–146; and for concerns regarding the composition of the building that bear indirectly on this problem, see P. Gros, L’Architecture Romain, du début du III siècle av J.-C. à la fin du Haut Empire, vol. 1: Les monuments publics, Paris 1996, pp. 175–176. For outright hostility, see C. Tiberi, “Saggio introduttivo,” in G. Ortolani, Il padiglione di Afrodite Cnidia a Villa Adriana: Progetto e significato, Rome 1998, pp. 9–16, esp. p. 14. Belardi (2006) advances completely different explanations for the anomalies of the Pantheon.
43 In November 2006, Haselberger presented objections at the conference at the Karman Center in Bern that may be summarized as follows:
The Propylaea of the Athenian Acropolis offer a precedent for the upper pediment (as Tiberi observed), which thus could have been intended from the outset (cf. my point i);
Other buildings exist with similarly tall/heavy pediments (iii);
The spacing of the modillions varies considerably, and so on this basis, it is hard to sustain arguments about intentions (iv);
Other buildings exist with similarly wide intercolumnations (v);
A capital inside the rotunda is not axially aligned with its pilaster, and so similar misalignments in the portico need not re
flect a change of project (vi).
I concede that points iii, iv, and v are relatively subjective, and that they cannot furnish conclusive arguments either way. Point i calls into question a major plank of the compromise hypothesis, yet it does not necessarily negate it, since the idea of a second pediment, perhaps inspired by the Athenian Propylaea, may only have arisen after the Pantheon project ran into problems. As for the misalignment of the capitals (vi), there is a difference between an isolated case in the interior and the systematic occurrence of a more severe misalignment on all four antae in the portico. In short, none of these criticisms is fatal, while the other points (ii, vii, viii, ix) remain unchallenged.