2 Palladio, Andrea, I quattro libri deU'architettura (Venice, 1570).Google Scholar Quotations according to the facsimile edition (Milan, 1980). See also English translation by Tavernor, Robert and Schofield, Richard: Palladio, Andrea, Four Books on Architecture(Cambridge, Mass., 1997).Google Scholar

3 Labacco, Antonio, Libro d'Antonio Labacco appartinente a architettvra nel qual sifigurano alcvne notabili anitqvità do Roma(Rome, 1552)Google Scholar; Ligorio, Pirro, Delle Antichità di Roma, ed. Negri, Daniela (Roma, 1989)Google Scholar; Serlio, Sebastiano, Tulle I'opere d'architettura et prospettiva (Venice, 1619)Google Scholar. See also the recent English translation by Hart, Vaughan and Hicks, Peter: Serlio, Sebastiano, On architecture(New Haven and London, 1996).Google Scholar

4 Desgodetz, Antoine Les édifices antique de Rome (Paris, 1682).Google Scholar Taylor, George Lidwell, Cresy, Edward, The architectural Antiquites of Rome (London, 1874).Google Scholar

5 One may be tempted to ask here about the unpublished surveys preserved in Palladio's drawings. It should be mentioned that among these drawings there are very few which represent Corinthian entablatures with dentils and modillions. Zorzi, Giangiorgio in I disegni delle antichità di Andrea Palladio (Venice, 1959)Google Scholar, provides reprints of six such entablatures: Porta dei Leoni, Verona (18), Porta Borsari, Verona (22), Arco dei Gavi, Verona (33), Arch of Constantine in Rome (38), Forum of Nerva in Rome (146), the Temple of Castor and Pollux in Naples (198) (numbers indicate illustration numbers in Zorzi's work). In most cases the manner of data presentation in these drawings is either inadequate for comparison with Palladio's published surveys in this paper, or the data are not legible, or present entablatures also represented in Book Four. In the latter case, it is reasonable to assume that the version published in Book Four is the one Palladio considered for the most accurate.

6 Palladio, , I quattro libri, p. 250.Google Scholar

7 This difficulty has been summarized in a recent article by Robison, Elwin C. ('Structural Implications in Palladio's Use of Harmonic proportions', Annali del Centro Internazionale di studi deU'architettura (1999), pp. 175–83, see especially p. 178).Google Scholar In Book Two Palladio provided a drawing showing the size of half of the Vicentine foot he used for the plans in that Book, and this foot size would be 35 cm. Nevertheless, due to the printing process that was used, this was certainly not the measure that was engraved in the original woodcuts. (In the process of printing wooden plates would slightly change their size and the size printed is not the same as the size engraved.) In the article mentioned, Robison lists solutions to the problem suggested by different scholars: Zurko 35.7 cm, Favero 34.75 cm, Burns, Fairburn and Boucher 35.4 cm ( Robison, , ‘Structural Implications', p. 178 Google Scholar). The smallest size proposed is 34.7 cm, proposed by Howard, Deborah and Longair, Malcolm ('Harmonic Proportions and Palladio's Quattro Libri ', Journal of the Society of Architectural Historians, 41 (1982), pp. 116-43, P.129)CrossRefGoogle Scholar. It is true that me biggest difference between these measures is about 3 per cent which would not result in a significant error when converting the surveys into the metric system. Yet when comparing surveys with Palladio's canonical versions of the classical orders one should not forget his tendency to insist on excessive precision when defining the elements of the classical orders; he would correct Vitruvius’ precepts for as little as 1/180th part of the lower column diameter ( Mitrovic, cf., ‘Palladio's Theory', p. 120 Google Scholar).

The problem is further aggravated by the fact that the foot size provided by Palladio in Book Two can only be taken to pertain to Book Two illustrations. These illustrations were prepared for publication in the late 1560s and it is reasonable to expect that the dimensions in these drawings were consistently expressed in the same foot size, whatever this size may have been. There is, however, no guarantee that the Book Two foot size is the same as the one with which Palladio measured the Roman temples, and that during his visits to Rome, the latest of which is usually dated at 1554, sixteen years before the publication of his treatise, he had already been using the same measuring standard which he later used to describe his own buildings in Book Two of his treatise. In fact, Lewis, Douglas in The Drawings of Andrea Palladio (Washington, 1981-82), p. 61 Google Scholar, pointed out that the unpublished drawings of Palladio's archaeological surveys occasionally combine measures in Roman and Veronese feet. It is neither certain nor even probable that in the process of preparing his old surveys for publication in the late 1560s he actually went through the effort of recalculating all the measurements stated in his old surveys into Vicentine feet, a huge job without a computer.

8 The nine relevant entablatures are those from the Basilica of Maxentius (4/3) and the temples in Mars Ultor (4/8), Minerva on Nerva's Forum (4/15) and (4/16), Castor and Pollux in Rome (4/47), Vespasian in the Roman Forum (4/49), Castor and Pollux in Naples (4/69), the Temple in Pola (4/79), the Maison Carrée in Nimes (4/85) and the Temple of Venus Genetrix (4/98). The entablature from the temple of Castor and Pollux in Naples was destroyed in an earthquake in 1688. Similarly, the part of the entablature above the architrave of the temple of Mars Ultor has not survived, and had already disappeared when Cresy and Taylor made their surveys in the nineteenth century ( Cresy, and Taylor, , The architectural Antiquities, p. 50 Google Scholar). According to Serlio's description, the section of this entablature above the architrave was already missing in the early sixteenth century ( Serlio, , Tutte l'opere, Book 3, fol. 88vGoogle Scholar). Both Palladio and Labacco, however, present this entablature in its full height, implying that all its parts were sufficiently preserved to be measured ( Labacco, , Libro, p. 12 Google Scholar, Palladio, , I quattro libri, 4/8 Google Scholar). While they present entablatures with similar morphology, the proportions of the major elements are different. Since this paper concentrates on the impact of Palladio's surveys on his formulation of the canon, and not on the accuracy of his surveys, I have simply taken Palladio's measurements of this entablature at face value.

9 Pierre Gros remarked that the only reliable published surveys of Roman entablatures ('… les seules relevés utilisables des entablements …’) are those produced by Toebelmann, in 1923: Gros, Pierre, Aurea Templa. Recherches sur l'architecture de Rome à l'époque d'Auguste (Rome, 1976), p. 252 Google Scholar; Toebelmann, Fritz, Römische Gebälke (Heidelberg, 1923).Google Scholar Since he made this statement, he and Robert Amy have published a survey of the Maison Carrée, but as for the elements of the entablature, that survey presents only the dimensions of the largest elements (architrave, frieze and cornice). Amy, Robert and Gros, Pierre, La Maison Carrée de Nimes (Paris, 1979).Google Scholar Tobelmann's surveys include only two entablatures from the list in note 7, those from the Forum of Nerva (4/16) and Basilica of Maxentius (4/3). Even if we disregard Gros’ warning about the accuracy of older surveys, we shall not find many published surveys of Roman entablatures. Desgodetz’ surveys cannot be used for the purpose of establishing the accuracy of Palladio's, since the measurements he provided were stated in ratios of the lower column diameter. In any case, in his book Desgodetz regularly commented on the difference between his and Palladio's surveys. There are also nineteenth-century surveys by Cresy and Taylor of the temples of Vepasian in Rome, Castor and Pollux in Rome and Minerva on Nerva's Forum in Rome. In Table 2 I have used the former two, whereas I have used Toebelmann's survey for the entablature from the Forum of Nerva (4/16).

10 Table 2 shows the results of the comparison of Palladio's surveys with later surveys of the temples of Vespasian and Castor and Pollux in Rome by Cresy and Taylor; Toebelmann's survey of the entablatures from the Basilica of Maxentius and the Forum of Nerva; and Amy's and Gros's survey of the Maison Carrée. All data are expressed in metres, assuming foot size of 34.7 cm. As regards morphology, Palladio's surveys are accurate even for very small details. Dimensions in Palladio's surveys are moderately accurate when it comes to major and bigger elements, but they tend to differ from modern surveys in the thicknesses of minor details, such as individual fillets and astragals. Where mistakes occur, they are far greater than 3 per cent and exceed the possible error which could have been generated by converting Palladio's data into the metric system (viz: ‘7). The third column of each comparison (marked D) shows the ratio between Palladio's and modern surveys. One can see that major elements tend to be accurate within 10 per cent; the error rarely exceeds a couple of centimetres. When measuring the elements of these entablatures, Palladio made an effort to be accurate within reasonable limits. It is safe to conclude that in the 1560s, when he was designing his canonical Corinthian entablature, he had at his disposal at least a couple of moderately reliable surveys of Roman entablatures morphologically very similar to Vignola's, which he could consult and use in the preparation of his canon.

11 von Hesberg, Henner, Konsolengeisa des Hellenismus und der frühen Kaiserzeit (Mainz, 1980), p. 18.Google Scholar

12 Vitruvius, , De architectura, 4.1.2.Google Scholar

13 Alberti, Leon Battista, De re aedificatoria, 7.9 Google Scholar; see also the translation by Rykwert, Joseph, Tavernor, Robert and Leach, Neil: Alberti, Leon Battista, On the Art of Building (Cambridge, Mass., 1988), p. 214.Google Scholar

14 Vitruvius, , De arch., iv, 2.5.Google Scholar

15 See Mitrović, , ‘Palladio's Theory', pp. 116–19Google Scholar, for a more extensive discussion of this problem.

16 Ibid., p. 61. See also da Vignola, Jacopo Barozzi, Regola delli cinque ordini (Rome, 1562), quotations according to 1572 editionGoogle Scholar; reprinted in da Vignola, Jacopo Barozzi, Canon of the Five Orders of Architecture (New York, 1999), pl. 14.Google Scholar

17 Bruschi, Arnaldo, ‘L'Antico e il processo di identificazione degli ordini nella seconda metà del Quattrocento', in L'emploi des orders dans L'architecture de la Renaissance, ed. Guillaume, Jean (Paris, 1992), pp. 11–58, particularly p. 48.Google Scholar

18 Angelini, Luigi, Le opere in Venezia di Mauro Codussi (Milan, 1945), pl. 85 Google Scholar for the portico of the Palazzo Zorzi a S. Severo and pl. 98 for Palazzo Vendramin-Calergi. For the latter entablature see also Howard, Deborah, 'Exterior Orders and Interior Planning in Sansovino and Sanmicheli', in Guillame, , L'emploi, pp. 183–92, particularly p. 189.Google Scholar

19 The Composite entablature was similarly undefined, but it was much less used.

20 For a discussion of this problem see Mitrovic, ‘Palladio's Theory …', pp. 116–19.

21 Ibid., pp. 121–25.

22 Ibid., pp. 123–26.

23 Ibid., pp. 124–25.

24 Vitruvius, , De architectura, 3.5.10.Google Scholar

25 Boucher, Bruce, ‘Nature and the Antique in the Work of Palladio', Journal of the Society of Architectural Historians, 59 (2000), pp. 296–311.CrossRefGoogle Scholar

26 Ibid., p. 298.

27 Ibid., pp. 301, 302.

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29 Palladio, , I quattro libri, p. 28.Google Scholar

30 Vignola, , Regola, pl. 26.Google Scholar

31 Ibid., pl. 2.

32 Ibid., pi. 2.

33 For the concept of visual judgement in Renaissance art and architectural theory see Summers, David, The Judgment of Sense. Renaissance Naturalism and the Rise of Aesthetics (Cambridge, 1987).Google Scholar

34 Zuccaro, Federico, ‘L'Idea de'Pittori, Scultori et Architetti', in Scritti d'arte di Federico Zuccaro, ed. Heikamp, Detlef (Firenze, 1961), pp. 150–306, p. 229.Google Scholar

35 Barkan, Leonard, ‘The Heritage of Zeuxis. Painting, Rhetoric, History', in Antiquity and its Interpreters, ed. Payne, Alina, Kuttner, Ann, Smick, Rebekah (Cambridge, 2000), pp. 99–109, p. 104.Google Scholar

36 Scott, Geoffrey, The Architecture of Humanism (New York and London, 1974), p. 144.Google Scholar