Utopia or Megalopolis? The Ichnographia of Piranesi's Campus Martius Reconsidered
Piranesi's vast reconstructed plan, or Ichnographia (fig), in his treatise Il Campo Marzio dell'Antica Roma of 1762 appeared at a key point in his theoretical and artistic development. Although this plan has recently been interpreted as a deliberate gesture of irrationality by the artist in reaction to contemporary tendencies in architectural design during the mid 18th century, the Ichnographia should, in fact, be read as a positive affirmation of confidence in the creative powers of the imagination.1 It is nothing less than a visual exhortation to modern architects to give full vent to creative licence through experiment in emulation of the ancient Romans. In this respect, therefore, the Ichnographia represents an artistic credo in defence of variety and formal complexity as opposed to the inflexible mentality and restrictive belief in simplicity, as Piranesi saw it, of avant-garde theorists such as Laugier, Winckelmann and their followers.2 If this monumental urban capriccio, therefore, is studied within the context of Piranesi's artistic development, such a positive Utopia should come as no surprise. On the contrary, the Ichnographia represents the logical outcome of certain deeply-rooted ideas first introduced some twenty years earlier by Piranesi in the Dedication of his Prima Parte di Architetture e Prospettive of 1743 on the threshold of an architectural career.
In the Prima Parte Piranesi, while thanking Nicola Giobbe for his early support and encouragement, castigated modern Roman architects and their patrons for lacking the imagination and vision in failing to respond to the challenge of the ruined antiquity surrounding them. As the young Venetian designer explained, he had no alternative in this sterile situation, but to find an outlet for his ideas in visionary schemes.3 Piranesi's serious intentions can be in no doubt for, on the evidence of surviving sketches in the British Museum (fig. fig,) it is clear that he worked out certain of his architectural fantasies in plan, section and elevation as a necessary part of this experimental process.4
The first mature expression of this creative ferment in the shape of a visionary plan occurs in: Piranesi's etched Pianta di ampio magnifico Collegio (fig.), included in the 1750 edition of his Opere Varie. This design originated in a highly imaginative synthesis of Palladian concepts, partly derived from Longhena's Santa Maria delia Salute, and ideas drawn from the Roman Baroque of Borromini (notably from Sant'Ivo delia Sapienza), together. with a fund of inspiration gained from the complex planning of the Imperial thermae, then being surveyed by Piranesi,5 That this ambitious production was not a negative exercise is borne out by its contemporary influence on student designers in Rome such as Peyre and Robert Adam,6 Predictably, on the other hand, this ideal plan came under attack by the more conservative architects, as represented by Sir William Chambers's scathing reference to the Collegia in the 1791 edition of his Treatise on Civil Architecture.7
This concern with visionary plans assumed a fresh significance and urgency as Piranesi gradually became involved in the cut-and-thrust of the Graeco-Roman controversy in the 1750s while he was preparing the Antichità Romane. Confronted by Laugier's sharp attack on the imaginative licence, or caprice, of baroque designers such as Borromini and his followers, in the name of Greek simplicity and functionalism, Piranesi intensified his studies of the complexity of Imperial Roman planning. 8 This is reflected in his tendentious reconstruction of the Nymphaeum of Nero (Antichità Romane, I, pl. XLI) (fig.)--an example of what might be regarded as ' poetic truth' in following the spirit rather than the letter of Roman achievement. This provocative approach is paralleled by other acts of creative archaeology when Piranesi attempted to recover vanished elements in
the plans of the Forum Romanum (I, pI. XLIII) (fig.) and of the Capitoline Hill (I, pI. XLIIII) in relation to existing fragments which he carefully distinguished by means of darker hatching in the etched plates. In this exercise of visionary reconstruction he would have been inspired by his current survey of the Villa Adriana at Tivoli (fig.), as published posthumously in 1781, by his study of the more original tomb designs fostered by Montano's 17th-century researches, as well as by Bianchini's earlier investigations of the Palatine site.9
During these years Piranesi's close friendship with the young Scottish architect Robert Adam was to provide an important source of encouragement in this speculative activity. In the Preface to the Antichità Romane of 1756 Piranesi had seized the opportunity once more to condemn the limited outlook of the contemporary architectural profession. In this respect he clearly recognised in Adam a kindred spirit who also saw the creative potential of archaeology as well as its practical application to the problems of modern design. A visual tribute to Adam was significantly included in the Via Appia fantasy which, as a secondary frontispiece to Volume II of the Antichità, opens a section demonstrating the imaginative range of Roman funerary
architecture.10 Meanwhile Adam's correspondence at this time reveals that Piranesi was already working on a giant master-plan which was originally intended to be an important part of the Antichità and which Piranesi had resolved to dedicate to the Scot.11 This plan was none other than the Ichnographia which Piranesi was to separate from the Antichità and eventually to publish as the key element in the Campo Marzio treatise, also dedicated to Adam, in 1762.12 This plan's lengthy gestation is indicated by the fact that Adam records seeing Piranesi at work on the dedicatory tablet (fig.) of the Ichnographia in his studio during April 1757 when the Scot paid a farewell visit before returning to Britain.13 This is independently corroborated by the date MDCCLVII appearing on the left-hand medallion in this tablet.
Moreover, the Ichnographia, far from being an isolated work was to be carefully integrated into the resulting treatise as the visual climax to a book polemically concerned with tracing the evolution of the Roman genius for planning. Sequences of plates were Piranesi's favourite means of visual argument and the Ichnographia (formed by pls. V-X combined), representing Rome in the Late Empire, is preceded by a series of plans showing the dramatic flowering of urban magnificence from primitive beginnings on the banks of the Tiber (figs.). In this particular respect the Ichnographia, as the salient feature of the Campo Marzio, should be seen as a conscious rejoinder to Winckelmann's interpretation of the evolution of classical antiquity as subsequently defined in the Anmerkungen über die Baukunst der Alten of 1762. In this publication the German scholar considered that a decline in taste was indicated by increasing richness and complexity.14 Piranesi, on the contrary, believed that fertility of invention and experiment were vitally necessary to the advance of modern architectural and urban design as a living syste--an opinion which he was later to emphasize in the debate of the Parere su l'Architettura in 1765 when Didascolo refers to the examples of Bernini and Borrornini.15
In support of the essential validity of his visionary reconstructions in the plates of the Campo Marzio, Piranesi developed certain illustrative techniques from the Antichità Romane; techniques involving a dialogue between his artistic intuition and archaeological facts as revealed by documents like the Severan Marble Plan, together with a close topographical investigation of the existing city.16 A representative example of this fruitful relationship between practical antiquarian study and flights of the imagination in the Campo Marzio is provided by the Theatre of Pompey. Here the surviving remains, embedded in medieval townscape near the Campo dei Fiori (fig.), were clarified by reference to the Marble Plan (pl. XVI) (fig.), then stripped bare of later accretions (pl. XVIII) (fig.), and eventually reconstructed imaginatively in the Ichnographia which was to be supported by selected aerial perspectives elsewhere in the treatise (2nd frontispiece and pI. XLVIII) (figs.).
As Piranesi made clear in his dedicatory address to Adam in the Campo Marzio, he intended the Ichnographia, together with the entire treatise, to be read as an encouragement to modern designers not only to emulate but to surpass their antique predecessors. By way of anticipating criticism of this creative licence, the artist observes:
I am rather afraid that some parts of the Campus which I describe should seem figments of my imagination and not based on any evidence: certainly if anyone compares them with the architectural theory of the ancients he will see that they differ greatly from it and are actually closer to the usage of our own times. But before anyone accuses me of falsehood, he should, I beg, examine the ancient [marble] plan of the city…, he should examine the villas of Latium and that of Hadrian at Tivoli, the baths, the tombs and other ruins, especially those beyond the Porta Capena, and he will find that the ancients transgressed the strict rules of architecture just as much as the moderns. Perhaps it is inevitable and a general rule that the arts on reaching a peak should then decline, or perhaps it is part of man's nature to demand some licence in creative expression as in other things, but we should not be surprised to see that the ancient architects have done the very things which we sometimes criticize in buildings of our own times.17
By the time that the Campo Marzio appeared in 1762 Piranesi was already beginning to abandon a narrow defence of Rome supported by archaeological and literary evidence alone. His opening publication in the controversy, Della Magnificenza ed Architettura de' Romani of 1761, had defended Italic achievements on the grounds of austerity and functionalism revealed by Etruscan and Roman Republican architecture. This approach, unwisely adopted as a debating position against Le Roy, Laugier and the Philhellene rationalists, openly conflicted with Piranesi's personal preference for the richly elaborate character of Late Roman ornament, copiously illustrated in the same treatise. By the early 1760s, as indicated by the additional plates to the Opere Varie and the Carceri, Piranesi had begun to express his predilection for complexity by developing a novel system of architectural composition, based on an imaginative synthesis of disparate styles.18 This approach--neo-Mannerist in form if not in intention--was ultimately given a theoretical justification in the Parere su l'Architettura. The Campo Marzio, therefore, represents a critical phase in the emergence of Piranesi's theoretical and artistic beliefs towards the middle of the decade.
In his challenging interpretation of Piranesi's Ichnographia, professor Tafuri considers that the artist intended this plan to be an implicit condemnation of the rationalism of the Enlightenment.19 In this respect there can surely be no disagreement if Laugier and his fellow rigoristi are regarded as the objects of the artist's attack: Where, however, it becomes difficult to follow professor Tafuri further is in his reading of a negative and, indeed, a destructive intention in the Ichnographia. In this particular interpretation of the architectural language of Piranesi's monumental plan, the artist is shown as deliberately creating a discordant system of design--a visual chaos resulting from geometric logic pushed to its ultimate extreme--in order to expose certain bourgeois values associated with rationalist architecture. Even if one were able to accept the connection between certain political values and the developing rationalist aesthetic in the contemporary architectural theories of Laugier and his successors, there are still insufficient grounds for disregarding Piranesi's conscious and unambiguously expressed aims in the Dedication of the Campo Marzio as well as in his other theoretical writings of the 1760s.20
While the origins of the Ichnographia can be traced back in a tradition of imaginative archaeology, pioneered by Pirro Ligorio in the 16th century and continued into Piranesi's youth by Fischer von Erlach, this visionary plan embodies a system of architectural composition which by itself is revolutionary in its consistency, as analysed by Vincenzo Fasolo in his seminar paper of 1956 (fig.).21 Various ancient monuments, such as the Pantheon, the Imperial mausolea and the Theatres of Pompey and Marcellus, are taken as points of topographical reference in a seemingly limitless web of planning forms. (Significantly, the Ichnographia is represented by Piranesi as but a major fragment of a new Marble Plan clamped to a wall for our inspection.) Individual elements are extracted from antique structures, such as tombs, thermae and amphitheatres, and rearranged in a process of creative synthesis which anticipates to a remarkable degree the later forms of French neo-classical planning.
Unlike the works of other fantasists, Piranesi's visionary compositions often found immediate application by contemporary designers because of their architectural validity. This is particularly evident in the widespread inspiration of the Ichnographia as an anthology of planning concepts for a wide range of architects extending from Adam, George Dance the Younger and Soane to Boullee, Ledoux and Neufforge, to mention only some of the more significant. It might also be added that a certain legacy from the Ichnographia can also be traced to neo-classical planning in Ledoux's Chaux, in Valadier's reorganization of the Piazza del Popolo in Rome, as well as in the monumental breadth of vision in the scheme for Napoleonic Paris by Percier and Fontaine.
These observations apart, if Piranesi had really intended the Ichnographia to represent a veritable Magalopolis--an enormous architectural system turning against itself to produce a state of auto-destruction--as professor Tafuri suggests, it is unlikely that the artist would have gone to such lengths in the Diverse Maniere d'adornare i Cammini, seven years later, to present a similarly positive defence of complex and innovatory compositions in the applied arts.22 Like all publicists of new and challenging ideas, Piranesi understood the need to exaggerate in order to convince, even if he was also prepared to be attacked for his eccentric opinions as he combatted the growing taste for architectural austerity. While it may be recognised that he adopted the anachronistic language of a frozen Baroque (to use Emil Kaufmann's phrase), by so doing Piranesi at least kept the debate open to designers such as Robert Adam who found little sympathy with the self-imposed simplicity of radical Neo-classicism.23 That the impact of Piranesi's polemical style of design was sufficiently felt by his rigorist critics and opponents is shown by the scarcely-disguised tone of disapproval in Bianconi's obituary of 1779 and the abuse poured on his Aventine buildings by Milizia some eight years later.24 What could be a more appropriate rejoinder by the creator of a positive Utopia in the Ichnographia than Piranesi's own words: «I need to produce great ideas and I believe that were I given the planning of a new universe, I would be mad enough to undertake it».25
1 M. Tafuri, G. B. Piranesi. L'Architettura come «Utopia Negativa», «Angelus Novus», n. 20, gennaio 1971, pp. 89-127, republished as Giovan Battista Piranesi. L'utopie negative dans l'arcbitecture, «L'Architecture d'aujourd'hui», n. 184, mars/avril 1976; In., Progetto e Utopia. Architettura e Sviluppo Capitalistico, Bari 1973, pp. 16-23. Professor Tafuri develops certain ideas from the above and extends them further in II complesso di Santa Maria del Priorato sull' Aventino: «furor analiticus» in the exhibition catalogue Piranesi: Incisioni, Rami, Legature, Architetture (ed. A. Bettagno), Fondazione Giorgio Cini, Venice 1978, pp. 78 if.
2 The relationship between Piranesi's theoretical ideas and those of Laugier, Winckelmann and others was first examined in R. Wittkower, Piranesi's «Parere su l'Architettura», «Journal of the Warburg Institute», II, 1938-1939, pp. 147 ff. (reprinted as Piranesi's Architectural Creed in Studies in the Italian Baroque (ed. M. Wittkower), London 1975, pp. 235 ff.), This approach has been modified in L. Cochetti, L'opera teorica di Piranesi, «Commentari», VI, 1955, n. 1, p. 35 ff. and has been examined with particular reference to French neo-classical theory and design in J. Wilton-Ely, Vision and Design: Piranesi's «fantasia» and the Graeco-Roman controversy in Piranese et les Francais. Colloque tenu à la Villa Medicis, 12-14 Mai, 1976 (ed. G. Brunel), Academic de France à Rome, Rome 1978, pp. 529 ff.
3 «Io non vi starò a ridìre la meraviglia, che n'ebbi osservando d'appresso, o l'esattissima perfezione delle architettoniche parti degli Edifizi, la rarità, o la smisurata mole de' marmi che in ogni parte rincontransi, o pure quella vasta ampiezza di spazio, che una volta occupavano i Circhi, i Fori, 0 gl'Imperiali Palagi: io vi dirò solamente, che di tali immagini mi hanno riempiuto lo spirito queste parlanti ruine, che di simili non arrivai a potermene mai formare sopra i disegni, benché accuratissimi, che di queste stesse ha fatto l'immortale Palladio, e che io pur sempre mi teneva innanzi agli occhi. Quindi è ch'essendomi venuto in pensiero di fame palesi al Mondo alcune di queste: ned essendo sperabile a un Architetto di questi tempi, di poterne effettivamente eseguire alcuna: sia poi ella colpa, o dell'Architettura medesima caduta da quella beata perfezione a cui fu portata ne' tempi delIa maggiore grandezza della Romana Repubblica, e in quelli de' potentissimi Cesari, che le succedettero: o pure ella sia coipa ancore di quelli che farsi dovrebbono Mecanati di questa nobilissima facoltà: il vero si è, che non vedendosi a nostri giorni Edifizi, che portino il dispendio, che richerebbe per esempio un Foro di Nerva, un Anfiteatro di Vespasiano, un Palazzo ill Nerone; ned apparendo de' Principi, o ne' privati disposzione a farneli vedere; altro partito non veggo restare a me, e a qualsivoglia altro Architetto moderno, che spiegare con disegni le proprie idee, e sottrarre in questo modo alla Scu1tura, e alia Pittura l'avvantaggio, che come dicea il grande Juvara, hanno in questa parte sopra l'Architettura; e per sottrarla altresì dall'arbitrario di coloro, me i tesori posseggono; e chi si fanno a credere di potere a loro talento disporre delle operazioni delIa medesima». (Prima Parte di Architetture e Prospettiue, 1743).
4 A sketch plan in the British Museum (1908-6-16-30 verso: fig. 142) appears to be related to a series of interior fantasies on the theme of a temple or basilica with flanking aisles viewed along the major axis which is finally resolved in the etched Vestibolo d'antico tempio of the Prima Parte (Focillon 12); see exhibition catalogue, Piranesi (ed. J. Wilton-Ely), Arts Council of Great Britain, Hayward Gallery, London 1978, pp. 21-22 (nos. 31, 32b and 33). The plans and, possibly, the fragmentary perspective in another British Museum drawing (1908-6-16-23: fig. 143) also appear to be related to the same design exercise.
5 The Collegio plan (Opere Varie, Focillon 121) is interpreted by Professor Tafuri as a negative gesture on the part of Piranesi in G. B. Piranesi. L'Architettura come «Utopia Negativa», «Angelus Novus», cit., p. 97. Its positive character, on the other hand, is examined with respect to the plan of Vanvitelli's Caserta in J. Wilton-Ely, The relationship between G. B. Piranesi and Luigi Vanvitelli in 18th-century architectural theory and practice in the forthcoming publication Luigi Vanvitelli e it Settecento europeo (ed, R. Di Stefano), Naples, p. 22: 9. In 1978 at the Piranesi Congress in Venice new light was thrown on the origins of the Collegio plan by Professor Cavicchi and Professor Zamboni in discussing their important discovery of a Piranesi sketch-book in the Biblioteca Estense at Modena which contains a preliminary study for this design (see pp. 188-191, fig. 74).
6 The influence of the Collegio and other such Piranesian planning exercises on J. M. Peyre is discussed in the present author's contributions to the exhibition catalogue, The Age of Neo-classicism, Arts Council of Great Britain, Royal Academy, London 1972, pp. 600-601 (1259 and 1260) and 605-606 (1268). While the impact of the Collegio on Adam's early designs is more diffused, the stimulus of Piranesi's visionary planning is reflected in certain ideal projects among the Adam drawings in the Soane Museum, London, as redrawn in A. T. Bolton, The Architecture of Robert and James Adam, London 1922, Vol. I, p. 18.
7 According to Chambers: «A celebrated Italian Artist whose taste and luxuriance of fancy were unusually great, and the effect of whose compositions
on paper has seldom been equalled, knew little of construction or calculation, yet less of the contrivance of habitable structures, or the modes of carrying real works into execution, though styling himself an architect. And when some pensioners of the French Academy at Rome, in the Author's hearing, charged
him with ignorance of plans, he composed a very complicated one, since published in his work; which sufficiently proves, that the charge was not altogether
groundless» (Treatise on Civil Architecture, London 1791, Introduction, p. 10).
8 See W. Herrmann, Laugier and Eighteenth-Century French Theory, London 1962,pp. 51, 61; 9 For Piranesi's survey of Hadrian's Villa, Tivoli, which began during the 1750s and was intensified in the next two decades, see the entry relating to the preparatory drawing in Naples for the plan of the Villa Adriana (etched and published by Francesco Piranesi in 1781) in the exhibition catalogue, Piranesi: Disegni (ed. A. Bettagno), Fondazione Giorgio Cini, Venice 1978, pp. 65-66 (77). The significance of the researches of Montano and Bianchini for Piranesi is examined in J. Wilton-Ely, The Art and Mind of Piranesi, London, 1978, pp. 45, 59-60.
9 For Piranesi's survey of Hadrian's Villa, Tivoli, which began during the 1750s and was intensified in the next two decades, see the entry relating to the preparatory drawing in Naples for the plan of the Villa Adriana (etched and published by Francesco Piranesi in 1781) in the exhibition catalogue, Piranesi: Disegni (ed. A. Bettagno), Fondazione Giorgio Cini, Venice 1978, pp. 65-66 (77). The significance of the researches of Montano and Bianchini for Piranesi is examined in J. Winton-Ely, The Art and Mind of Piranesi, London, 1978, pp. 45, 59-60.
10 According to Adam, writing in April 1756, «in one of the frontispieces
representing the Appian Way in all its ancient splendour, with ail the mausoleums of the Consuls, Emperors &ca., he [Piranesi] has taken the occasion to put in Ramsay's name and mine, with our Elogiums, as if buried in these tombs» (J. Fleming, Robert Adam and his Circle in Edinburgh and Rome, London 1962, p. 207). Adam's relationship with Piranesi is also discussed in " D. Stillman, Robert Adam and Piranesi in Essays Presented to Rudolf Wittkower (ed. D. Fraser), London 1967, pp. 197 ff. which also illustrates one of two architectural fantasies sketched by Piranesi for the Scottish architect, now in the Soane Museum, London.
11 The first surviving reference ot the future Ichnograpbia of the Campo Marzio in Robert Adam's correspondence occurs in a letter to his brother James written on June 18 1755. According to Robert, Piranesi «threatens dedicating his next plan of ancient Rome to me, but of this I have no certainty ...» (Fleming, op. cit., p. 354). Subsequently, on July 5 1755, he wrote: «You will soon see my name in print as Piranesi has absolutely rejected the Cardinal he intended to dedicate his plan of ancient Rome to and has dedicated it to me under the name of Architect, Friend and Most Knowing in and Lover of the Antique» (In.).
12 Although the master-plan had clearly been intended to form part of the Antichità Romane, in a letter of September 13 1755 Adam describes how he had «got» Piranesi «to finish the whole of Rome and to publish it alone without joining it in a book whose principal dedication was to my Lord Charlemont, which made mine less regarded, whereas mine being sold separate all the world will purchase it and have no other name to detract from the honour
of the intention» (Fleming, op. cit., p. 354). The plan was still unfinished in May 1756 when it was described in the Preface to the newly-published Antichità as «il grande Iconografia di Roma antica che sto in procinto di dare alla luce» (Vol. I, p. 40).
13 In a letter of April 9 1757 Adam describes finding Piranesi at work on the dedicatory tablet to the Ichnographia which was engraved «in the most simple way could be invented in Latin to this purpose: To Robert Adam Britain, Patron of Architecture, This plate of Campus Martius is dedicated by John Batista Piranesi. Then on a freize above is a medal, where Fame points to a piece of architecture and leans on my shoulder in the attitude of going off to proclaim my praises. Round the medal is this inscription: Robert Adam Architect, Member of the Academy of St. Luke at Rome and of Florence and of the
Institute of Bologna--all in Latin. In another medal Piranesi has put my head and his own joined, forming a Janus or double-faced head, with both the names of the dedicator and dedicated on it, but this was not finished when I saw it» (Fleming, op. cit., p. 231). The janus-headed composition described in the right-hand medallion in the dedicatory tablet appears to have been replaced in the published work by a version with superimposed heads of Adam and Piranesi. Meanwhile the Scot appears to have asked the artist to feature him in the preface to the Campo Marzio as well and on a further visit to Piranesi's studio was pleased to read «many handsome compliments as to the extraordinariness of my genius and the unblemished probity of my character that envy durst not dare attack» (In.).
14 In Winckelmann's view «architecture suffered the same fate as the old languages, which became richer when they lost their beauty; this can be proved by the Greek as well as the Roman language, and as architects could neither equal nor surpass their predecessors in beauty, they tried to show that they were richer» (as quoted from the translation by S. Powell of a passage from the Anmerkungen über die Baukunst der Alten, Leipzig 1762, in D. Irwin (ed.), Winckelmann. Writings on Art, London 1972, p. 87).
15 According to Didascolo: «Vorrete dire i Bernini, i Boromini [sic], e quanti altri hanno operato senza pensare, che gli ornamenti debbono nascere da ciò che costituisce l'Architettura; ma in costoro chi vi credete di biasimare? Il più grande Architetto, che vi sia stato, voi biasimate ache sia per esservi, Biasimate l'esperienza di quella moltitudine di professori che, da quando fu inventato un tal genere d'Architettura, finché non resto sepoltofra le rovine, fece sernpre così: di quella moltitudine che, dopo rifurto codesto genere, non seppe ne ha saputo fare altrimenti» (Parere su l'Architettura, 1765, p. 12).
16 The surviving fragments of the Severan Marble Plan had already played an important role in the Antichità Romane where Piranesi reproduced them extensively in Volume I, pls. I-V. For a modern evaluation of the Marble Plan see G. Carretoni, A. M. Colini et al., La Pianta Marmorea di Roma antica, Forma Urbis Romae, Rome 1960.
17 «Sebbene ciò di che io piuttosto tener debbo, si è, che non sembrino inventate a capriccio, più che prese dal vero, alcune cose di questa delineazione del Campo; le quale se taluno confronta coll'antica rnaniera di architettare, comprendera, che molto da essa si discostano, e s'avvicinano all'usanza de' nostri tempi. Ma chiunque egli sia, prima di condannare alcuno d'impostura, osservi di grazia l'antica pianta di Roma..., osservi le antiche ville del Lazio, quella d'Adriano in Tivoli, le terme, i sepolcri, e gli altri edifizi di Roma, che rimangono in ispezie poi fuori di porta Capena: non ritrovera inventate più cose dai modemi, che dagli antichi contra le piì rigide Ieggi dell'architettura. O derivi pertanto dalla natura e condizione delle arti, che quando sono giunte al sommo vanno a poco a poco in decadenza e in rovina, o cosl porti l'indole degliuomini, che nelle professioni ancora reputansi lecita qualsisia cosa; non è da meravigliarsi, se troviamo eziando dagli architetti antichi usate quelle cose, che nelle fabbriche nosttaIi talvolta biasimiamo» (Campo Marzio dell'Antica Roma, 1762: English translation quoted from J. Scott, Piranesi, London 1975, pp. 166-167).
18 For the significance of the four small architectural fantasies added to the Opere Varie (FociIlon 123, 126-128) and the two new plates of the reissued Carceri (Focillon 25 and 26), see J. Wilton-Ely, The Mind and Art of Piranesi cit., pp. 78, 89.
19 M. Tafuri, G. B. Piranesi. L'Architettura come «Utopia Negativa», «Angelus Novus», cit., pp. 101-108.
20 Piranesi's main polemical treatises of the 1760s, incorporating his theoretical writings, have been reproduced in a single volume in G. B. Piranesi: the Polemical Works (ed. J. Wilton-Ely), Famborough 1972.
21 V. Fasolo, Il «Campomarzio» di G. B. Piranesi, «Quaderni dell'Istituto di Storia dell'Architettura», n. 15, Rome 1956, pp. 1 ff. (see fig. 155).
22 See G. B. Piranesi: the Polemical Works (ed. J. Wilton-Ely), cit.
23 E. Kaufmann, Architecture in the Age of Reason, New York 1955, pp. 105 ff.
24 G. L. Biaconi, Elogio storico del Cavaliere Gianbattista Piranesi, «Antologia Romana», XXXIV-XXXVI (Feb.-Mar., 1779), as republished in ID., Opere, II, Milano 1802, pp. 133-134; F. Milizia, Roma nelle belle arti del disegno, Bassano 1787,p. 197.
25 J. G. Legrand, Notice historique sur la vie et les ouurages de J. B. Piranesi... Rédigée sur les notes et les pieces communiquees par ses fils.., Paris, Bib. Nat., MSS. nouv. acq. fr. 5968, as transcribed and edited by G. Eouart and M. Mosser in A propos de la «Notice bistorique sur la vie et les ouvrages de J.-B. Piranesi»: origine et fortune d'une biographie, Piranèse et les Français (ed. Brunel), cit., p. 248.