1“This is certainly a strange country; a land of volcanoes and earthquakes; of sulphur and hot springs; fertile, yet uncultivated and deserted; encumbered with the ruins of former greatness and with memorials of the crimes and follies of mankind1.” With these disquieting words the Swiss traveler André Viesseux described the Phlegraean Fields, as he saw them in 1819. The troubling geological phenomena of the volcanic area north of Naples, including among other features an abundance of hot mineral springs, had already been for centuries the object of a pointed naturalistic and antiquarian interest. While the beauty of the places had attracted visitors at least from the Roman period, when the area became a popular resort for the upper class of the late Republic and the Empire, the threat of complex geological phenomena, often verging on the inexplicable, had provided a rich background for discussion and fascination2. Despite this, the history of the celebrated baths of Pozzuoli, Bajae, Misenum, and Ischia in the early modern period – from the Renaissance onwards – has yet to be written, even if there has been no lack of studies on specific points, periods, and aspects3.

2My contention will be that this story cannot be properly understood without taking into account the history of medicine and therapeutics, both at a European and at a local level – but also the history of what we would now call earth sciences, as well as the history of antiquarianism. The features and behavior of springs of hot water and exhalations of airs from the bowels of the earth have been an important sign, or symptom, in the observations leading to a new science of the earth in this period. The early modern natural philosophical discourse on meteorae, and the medical tradition deriving from the Hippocratic notion of airs waters places and the Galenic theory of non-naturals, especially air, were fraught with niceties that it may be difficult to appreciate. However, an integrated approach is necessary in order to do justice to the richness of the early modern discussions on mineral waters and spas in this area4. Everywhere in Europe, medicine and natural philosophy did perceive the environment as a whole (that also included historical monuments, remains and antique traces), and this was especially true in a worrisome territory as the area surrounding the city of Naples.

3Here I will briefly reconstruct the history of the texts dealing with mineral baths and sudatoria, and their therapeutic uses, in the period that goes roughly from the early 16th century to the late 17th century, a crucial period for the development of medical knowledge in Naples and in Italy, where and when conflicting models of the body and of its physiology often also involved the construction or appraisal of conflicting models of the body of the earth. Medical men – physicians, but also learned surgeons and apothecaries, and in some cases patients themselves – contributed to the idea that medicine held the key to the secrets of both ‘bodies’. Medical knowledge and medical men thus became, or proposed themselves as, the authorized interpreters of the environment, of its effects on human bodies, and ultimately also of the therapeutic use of baths5.

Ruptures and continuity in the Cinquecento

4In October 1538, a spectacular and unprecedented natural event took place near Pozzuoli, in the very heart of the Phlegraean Fields: an entirely new volcano began erupting, becoming a “mountain” of remarkable height in only a few hours6. In the two years preceding the eruption, seisms had been so frequent as to ruin almost all the buildings, both ancient and modern, in the area. In the preceding two days, the sea had suddenly retired, allowing fishes to be caught by the hand: an ominous sign, whose character of portent soon became the object of discussion. After the eruption, the whole of the area of Naples was touched, physically by the cloud of ashes projected onto a very large area, but also by the wildest rumours concerning the fate of the city and its surroundings. Among the Roman remains destroyed by the Monte Nuovo eruption there were some very special ones, namely, some of the best preserved ancient baths – built on springs of mineral waters – in the South of Italy, still in use at the time of their destruction.

5Therapeutic and cosmetic baths in the Phlegrean Fields had been in almost uninterrupted use since Antiquity, and the qualities of mineral waters in Pozzuoli, Bajae and the Ischia were well known; among the authors that mention them we find Strabo, Livius, Tibullus, Pliny, Celsus, Seneca, Galen, Oribasius. In the Middle Ages, a long tradition of use remembered by chronicles and by travelers, as by Benjamin of Tudela, writing in the 12th century, culminated in the thorough description contained in the De Balneis by Petrus Ebolitanus. The poem, written in the XIII century, enjoyed an enormous success and became the standard description of the springs and baths and of their therapeutic diversity. Many late medieval manuscripts of this text were lavishly illustrated7. As it has been said, «there is no other instance in secular book illumination of a subject of predominantly local interest – as opposed to a herbal or a romance – where we possess such a wealth of illustrative material8. » The history of the images of the baths is a long one, with a remarkable development, as we shall see, in the 17th century.

6In the early 16th century, before and after the rupture represented by the 1538 catastrophe, the baths benefited from, and helped fostering, the development of the local industry of the printing press, becoming one of the standard subjects for “scientific” and touristic books – the two genres are not always easy to differentiate9. As also happened in other bathing localities, guides and other publications exploited the patients’requests for a reliable itinerarium to the baths, and extolled the therapeutic virtues and features of the springs10. A substantial number of short treatises, collections of medieval and humanistic compositions, and other texts were published, and rewritten or commented, suggesting a continuity in the use and description of localities and springs from the late antiquity onwards11. However, continuity is not obvious, even before the Monte Nuovo eruption, that dramatically altered topography and life in the area. Claus Kaufmann has suggested that already in the Middle Ages Bajae had comparatively declined, to the advantage of Pozzuoli and of the Averno lake12. Livio Petrucci, concentrating on the use of baths for medical and other purposes, observes that many springs had already been abandoned in the 15th century13. What is certain is that the decline of some springs was accelerated by the eruption, and that the dramatic opinion expressed by Simone Porzio, «balnea illa, tot saeculis caelebrata, quaeque tot aegris salutem praestabant, cinere sepulta iacent»14, may indeed be true, at least for some of them. Despite this, destruction was far from complete, and while it is difficult to entirely agree with the thesis of the end of Pozzuoli as a favorite Neapolitan location for medical bathing, the eruption contributed to changes in the uses and locations of baths15. After 1538, the town and its surroundings were indeed partially in ruins, but there were signs of revival. The Spanish Viceroy Pedro de Toledo, who cultivated a strong interest in the sciences, had a villa and beautiful gardens build in the town, so as to try and convince the inhabitants to come back. In fact, we know from many testimonies that baths in Pozzuoli were active, if not thriving, from the 1550s and 1560s onwards16.

7The eruption also had the effect of bringing dramatically to the fore an ancient and altogether not forgotten question, namely, the one of the troubling double character of the “airs, waters and places” in the Phlegraean Fields, and in the Campania felix as a whole. In this region the fertility of the soil and the beauty of the skies was commonly considered to be matched, indeed caused, by subterranean fires and exhalations, threatening destruction of men and artifacts. A striking image of the Bagni di Pozzuoli is to be found in the Studiolo of the Tuscan Grand Duke Francesco de’Medici, who was committed to scientific practice and in particular to alchemy. The painting had been commissioned to Girolamo Macchietti and was completed in 1572. While not being painted from life, it well represents the ambivalence perceived by authors writing on the natural features of Campania17. It is mainly occupied by a bathing scene: naked men sit or are immersed in water, against the background of a classical architecture, ornamented with columns and busts. Looking attentively, however, one can spot on the left margin of the scene, clearly visible against the dark nocturnal sky, somewhat lurking behind the classical harmony of the image, the fire of an erupting mountain. It is interesting that this representation of the baths is to be found in the section of the Studiolo devoted to the element of Fire, instead than in the section on Water, as it might be expected18. Mineral springs were kindled by, and existed because, the presence of fire in the bowels of the earth.

8In the same years of the Monte Nuovo eruption, a lively discussion on earthquakes, subterranean “winds” and exhalations, and on their role in various geological phenomena, was taking place in Italy and in Europe, building on ancient theories and narratives, and partially and painstakingly transforming them19. Explanations of earthquakes, mainly deriving from Aristotle’s Meteorologica, connected mineral springs to subterranean sulphurous exhalations; earthquakes had plagued Pozzuoli’s area before the eruption, and it was all too evident that mineral waters derived their heat and qualities from the same sources, that is, from subterranean mines (miniere) and from their combustion. Theories in this sense were expressed by a number of authors writing on the subject and belonging to the lively Neapolitan milieu of natural philosophers and physicians active at the end of the 16th and the beginning of the 17th centuries20.

9We will mention here only one example, the Historia Naturale (1599) by Ferrante Imperato21. A learned apothecary and natural philosopher, Imperato dealt at length with waters and their properties and origins in the sixth and seventh books of his work. His aim was to build a general theory of waters and their mineral properties, but, rather frustratingly for the modern reader, he avoids any specific discussion of the qualities and medical properties of the local baths while discussing the qualities of waters in general. However, in the XXI chapter of book VIII he comments on the airs of the Phlegraean fields, whose quality should indeed be very unhealthy, if one considers the poisonous exhalations coming from places such as the Grotta del cane in Agnano. He mentions one of the Pozzuoli baths (the Ortodonico) where the vapors, normally helpful for patients, become mortal when the Borea (northern) wind is blowing. At the same time, and in a rather paradoxical fashion, waters and airs that have been in contact with subterranean fires help to restore people to perfect health, by dissolving obstructions and helping fluidify humours. In Imperato’s opinion, fires and heat are a crucial factor in purifying the airs and waters and in exhalting the therapeutic properties of the minerals they contain.

Chemistry and the anatomy of waters, Iasolino to Bartoli

10In 1607, Giulio Cesare Capaccio published a learned and practical guide of the Phlegraean Fields and in particular of the city of Pozzuoli and of its surroundings, dedicated to Pozzuoli’s citizens, A’cittadini di Pozzuolo22. This contained a list, clearly meant for visitors and patients, of the available baths and sources, with a short indication of the diseases they could help healing. Capaccio underlines the richness and diversity of the treatments – not only baths, but also sudatoria, where natural vapors could be absorbed through the skin or by inhalation, or mud or sand applications, as in the Solfatara. While his work is meant as a sort of advertising of the Phlegraean sites, Capaccio does also mention the island of Ischia, and the role played by Giulio Iasolino in the rediscovery of its ancient, and hitherto comparatively neglected, baths and mineral springs23.

11The rich 16th century literature on the mineral baths of Bajae and Pozzuoli often contained detailed, “scientific” accounts of the relation between specific baths and therapeutic effects, accompanied in some instances by a sketchy appraisal of the chemical qualities of the waters, assessed through the use of chemical techniques, such as distillation24. However, the approach of these texts seems somewhat amateurish, when compared to the systematic assessment of the properties and qualities of metals, springs and waters that can be read in Iasolino’s De Rimedi Naturali che sono nell’Isola di Pithecusa (1588)25. Giulio Iasolino (1537/8-1622?) was an anatomist and physician from the town of Monteleone, in Calabria Ultra. He had been a pupil of the Sicilian Giovanni Filippo Ingrassia and he became lecturer of anatomy and medicina practica at Naples’Studium sometime in the 1560s26. Iasolino had long been a practicing anatomist before turning to the description of Ischia waters, and he accurately sketches an “anatomy” of the island, both of its subterranean and of its external features. He describes in detail the mineral substances that can be found in the island: the alum («allume27»), the remarkable quantity of niter («copia grande di nitro28») and the traces of lodestone («magnesia»). The island is a sort of open air theater of minerals, that can be detected by fastidiously observing and recording the different colours of its rocks and stones, hinting to an unbounded richness and mixture of diverse substances29.

12The best modern biographer of Iasolino, Paul Buchner, who has been able to see a manuscript copy of the book as it had been originally planned, states that a lengthy chapter on volcanoes has been lost in publication30. We cannot obviously know in detail what it contained, but is apparent that the connection between subterranean fires – in many senses, a natural laboratory where mineral substances, metalli, are processed by means of heat – and the chemical qualities of the sources is crucial for Jasolino. In fact, while he is largely dependent on Andrea Bacci’s De thermis, recently (1571) published in Rome, he differentiates himself from his better-known colleague because of his decidedly chemical approach. This explains why he begins his book on Ischia waters with a lengthy tractation on fire: in his opinion, no art or technical skill or knowledge could have been found or preserved and transmitted without the help of fire: «all the arts were found by means of the fire, and the fire keeps them going31». Consistently, he admits to having sought the help of a skilled chemist in order to perform thorough experiments on the composition of Ischia waters and on the mixtures of substances therein. He admits to having found no gold or silver in them32. Despite recent groundbreaking works, we do not yet know enough about the diffusion of chemical and Paracelsian doctrines in Italy, or in Naples, in the late Cinquecento33. Iasolino’s text encourages a better assessment of the practice of chemistry in Naples, and of its connection to anatomy. In fact, as late as the end of the 17th century, “anatomy” was still meant as indicating the practice of dissecting bodies as much as the art of knowing the composition of substances through chemical processes.

13In his exam of Ischia sources, Jasolino does not limit himself to anatomy and chemistry. From the point of view of practical medicine, his book offers a fascinating example of the multiple connections between the classification of diseases and the classification of mineral substances. Mineral waters and sands mainly have a local and mechanical effect on bodies, and as such they present an interesting parallel with at least some of the effects produced by means of surgical operations. However, at the same time, waters have a wide array of effects on bodies in general, that can be resumed in the two extremes of restriction (stringere, astringere) and opening, mollifying and slackening (aprire, mollificare). But what is really striking in Jasolino’s text is his use of historia, both in the sense of personal experience as in the sense of historical knowledge34. His effort to identify baths and their exact location is remarkable: he lists 11 sources of fresh water, 35 of hot waters, the mud in Fornello, 5 locations of hot medicated sands, and 19 sudatoria, sources of hot vapour. He boasts of having carefully examined them all in person, and indeed he is known for having stayed in the island for long periods of time35. In order to even simply find the springs in an environment that was still comparatively underdeveloped and wild, he mobilizes historical knowledge, both in the form of erudite textual information as in the research of local witnesses and guides. He is acutely aware – as indeed had been the authors of the works on the baths of Pozzuoli and Bajae – of the modifications, some of them dramatic, that have occurred in this unstable territory in the course of time, changing it beyond recognition. He thus constructs what can be considered to be a sort of “philology” of the environment, that has to be read as a palimpsest:

«Come per la differenza, & mutatione de’ tempi si sono perdute, o tralasciate, & di nuovo si sono trovate, o ridotte in uso molte cose importanti; così si pruova essere avvenuto intorno à bagni... a’ nostri tempi si sono manifestati tanti nuovi paesi, tante Isole si sono trovate, tante, e tanto diverse, & non conosciute nationi, tanto mare, tanta terra, tanti riti, & costumi sono venuti a nostra cognitione, che non fuor di ragione si dice esersi truovato un nuovo mondo36. »

14His task is particularly difficult; while Pozzuoli and Bajae had been well known and explored throughout the Middle Ages and the Renaissance, Ischia was less well known, and the rupture with ancient testimonies was more marked.

15Jasolino’s work on the baths of Ischia was dedicated to a noblewoman, the duchess Domenica Geronima Colonna – the sister of Marco Antonio Colonna, the commander of the Christian fleet at Lepanto – who in 1559 had married Camillo Pignatelli di Monteleone, Jasolino’s motherland. The lady seems to have been directly interested in the exploitation of the baths: she had rearranged and restored the baths of Gurgitello, that Jasolino describes at length. At the time, Ischia was emerging from a long period of neglect and abandonment; for a long time it been under the pressure of North Africa piracy. In 1544, in an incursion by the redoutable Hayreddin, 2000 of its inhabitants had been captured and sold as slaves. After Lepanto, the island had benefited from a period of comparative safety: the population had increased, and Iasolino’s work reflects this changing reality as much as the crisis, if not downright decline, of the baths on the mainland.

16Jasolino’s work on Ischia enjoyed great reputation and was reprinted many times, and as late as 1763. After almost a century, the Neapolitan physician and iatrochemist Sebastiano Bartoli (1629-1676) published two works on the baths that, once again, were composed along the “chemical” line. These are the Breve ragguaglio de’bagni di Pozzuolo (1667) and the lengthy, posthumous and incomplete treatise called Thermologia Aragonia (1679)37. Bartoli’s interest in the chemistry of mineral waters was strong, due to his chemical background, influenced by Jean Baptiste van Helmont’s theories38; but it would have probably come to nothing without his involvement in the restoration of the baths attempted by the Spanish Viceroy Pedro de Aragón (who reigned from 1666 to 1671). The story is well known, but nevertheless interesting if seen in continuity with Jasolino’s work. The Viceroy, whose patronage helped Bartoli to overcome many an obstacle in his career and publications, had an interest in the theories and practices of the innovative, if heterodox, scientific Neapolitan milieu, embodied by the Accademia degli Investiganti. As the story goes, he had been inspired by the reading of Giovanni Elisio’s Succinta instauratio de balneis totius Campaniae (1519) to try and save from destruction the baths that were not yet ruined beyond repair. He had thus asked Giulio Cesare Bonito, Duca di Isola, and the physician Vincenzo Crisconio, to trace the extant baths in the Phlegraean area and to precisely map their sites. Of the traditional 35, remembered by Elisio and by many others, they had only been able to identify thirteen. In the same year, Bartoli, who was already one of the Viceroy physicians, had, in his words, already begun a project aimed at «fare di quelle [fonti] nell’imminente Estate una esatta anatomia per mezzo della distillatione, e dedurne regole certe della loro efficacia39.»

17In 1666 Pedro de Aragón had then appointed a board in order to complete the task; it was composed by Diego Ragusa, Protomedico, and by other physicians – besides Bartoli himself, Francesco Liotta, Gio: Domenico Turris, Vincenzo Protospataro, Antonio Cappella, Alesio Alonya, Leonardo Di Capua, Bernardino Corvisiero, Domenico Buonincontro, Vincenzo Crisconio, Giacinto di Felice40. Leonardo Di Capua and Bartoli were prominent among the ‘moderns’, as opposed to the ‘Galenists’, who advocated a traditional notion of medicine. Their participation in the board, as well as Bartoli’s works, point at the attempt by iatrochemists, who had gained a place among patients in the city, but whose practice and therapeutics were fiercely adversed by the Galenists, to use the baths and their exploitation in order to legitimize their knowledge. Chemistry presented a clear advantage in the discovery, analysis and assessment of the properties of mineral medicated waters41. However, this was not an easy task. Waters and springs were by no means easily left to physicians; Bartoli found himself in competition with an altogether different professional, the engineer Lorenzo Roggiano, who according to him did not possess the knowledge necessary to find or discover the ancient sites, let alone restore them to the ancient perfection or therapeutic use42. Bartoli claims to have been able to do so by means of an attentive reading of ancient and medieval sources on the springs. In fact, he did so by following the method already experimented by Jasolino, also adding an enhanced awareness of the possibilities offered by the two combined skills of the philologist and of the natural philosopher.

18In Bartoli’s opinion, the origin and main source of the heat and mineral qualities of the springs is to be found in the subterranean, liquid sulphureous fire – the «foco liquido, se non vogliamo dire quel Solfo risoluto in acqua dall’industria d’un Vulcano interraneo43» – active in the abyss under the Solfatara volcano. Bartoli also deals with other sources, namely, textual ones: he correctly traces the origins of the “modern” works on the baths to the texts by Giovanni Villani and by Alcadino, that is, by Pietro da Eboli, whose name and authorship were not yet as known as his poem was widely read. He also states that he has in his possession several ancient manuscripts on the topic, among them an illustrated one, reproducing the ancient decorations that explained which parts of the body could be treated by the different waters, thus enabling a widespread and lay use of the baths and other treatments. In fact, Bartoli’s – and the Viceroy’s – dream would have been to restore the epitaffi, the inscriptions and visual representations that in some cases could be traced back to the ancients’use. There is a well-known anecdote, also remembered by Bartoli who considers it a mere legend, concerning the misdeeds of the physicians of Salerno, who had attempted the destruction of the epitaffi, because of the threat they posed to their professional role in advising patients on bathing. The physicians had succeeded in destroying part of the inscriptions, but they had been punished by divine anger and had drowned, returning from the expedition, in a shipwreck near Capri. The narrative underlines the importance, still acutely felt in Bartoli’s times, of images in the use of baths in Pozzuoli and Bajae44. It also points to the awareness, somewhat typical of the milieu to which both Jasolino and Bartoli belonged, of the possibility of a medicine without physicians, that is, of a natural and spontaneous use of treatments by lay people, avoiding the mediation of learned, traditional medicine.

Conclusions

19Baths and sources of mineral waters in the early modern age cannot be seen as isolated phenomena. They were part of a troubling, complex environment, that included, in a vertical disposition, subterranean, terrestrial and celestial elements, including exhalations, winds, and airs. Renaissance readings and commentaries of one of the capital texts of the ancient knowledge in this field, Aristotle’s Meteorologica, helped to reinforce the awareness of the connection between health, disease and the environment; in fact, it was prominent for iatrochemistry and iatromechanics, as Descartes’ Meteorae show, and in the Hippocratic revival in the Enlightenment. While this is true throughout Europe, waters in the Campania Felix presented specific and somewhat paradoxical features; their therapeutic uses were also connected with, if not altogether caused by, the strong destructive powers of earthquakes and volcanoes, or of poisonous exhalations. The healthiness of the “airs” and the fertility of the soil in the surroundings of the city of Naples were celebrated, but they could just as easily turn into threatening and catastrophic phenomena, that could go from the “bad” nature and constitution of human bodies and temperaments – quick and hot-tempered, and as such violent and prone to lust45 – to earthquakes and volcanic eruptions.

20In actual fact, baths were the locus of complex professional and social negotiations: besides the question of the competition between different professional knowledge and expertise – with patients claiming to be able to avoid the physician’s advice – more direct political issues could be at stake. Bathing could for instance be used as a pretext to avoid court engagements, e. g. as related by Capaccio, who quotes the scathing answer given by viceroy Count Olivares to a courtier asking a licence to go to pass the waters: «Dunque come si fa in Spagna, & in altri lochi, senza questi solfi, e senza queste acque46?» However, physicians and other medical practitioners enjoyed a position of privilege in their knowledge of these phenomena, both because of their training in natural philosophy and because of the longue durée tradition of medical reflection on “airs, waters, places”. The physicians’ability to read the signs only visible at the surface of the animal body enabled them to read the often puzzling signs and symptoms of the body of the earth47. The latter also included historical signs and remains, related to changes occurring in time. While the waters, fires and airs of many European countries could be envisaged as an unchanging factor, or at best as a factor changing only with seasons or through human activity, in Naples the succession of geological phenomena, the development of sophisticated human artifacts and the destructive power of nature combined in a peculiar and dramatic way. Physicians were called to interpret a changing and thus extremely worrisome territory, where human bodies themselves were subject to instability.