Nikola Benin, Ph.D
The Church of Orsanmichele is of a rectangular shape of 33,2×22,4m. It has ten external pilasters and two internal ones. It is 40,7m high, resulting in three storeys. The ground floor is recognizable by its arches and large windows, and the sculptures present in the fourteen niches that go around the structure of the building. The first and second floors are rhythmed by two rows of two-lighted windows overhung by the various shields of Florence and their gothic ornaments. In the corners stand medallions representing the four seasons. As for the main door, it was built later, is in wood, and has the inscriptions OSM on it (standing for Orsanmichele).
The building as we now know it was built in 1337. Originally, at the same spot, was an oratory built in the second half of the VIIIth century in the gardens of a Benedictine monastery dedicated to St. Michael Archangel. It was then used as a loggia[1] in the 1240s, by the corporation of merchants, to store wheat by 1284. It was then destroyed by a fire in 1304, and rebuilt in 1337 in its actual structure.
Historical context
By the end of the XIIIth century, Florence started to be ruled by the arti, or guilds, of which seven were dominant (the arti maggiori), and fourteen were “inferior” (arti minori). Before those guilds became so powerful, Florence was ruled by an elected assembly. But the former became so rich, that they put aside the richest families of Florence and got control over the city (except the Medicis, whose reign started at the end of the XIVth century with Bicci, founder of the Medici Bank in 1397).
The system of Guilds existed in Florence, but also throughout Europe, perhaps as a result of the collegias of Ancient Rome. During the Ancient Times, the latter were already a way of maintaining social order. As for during the Middle Ages, they started to appear in growing cities around the Xth and XIth century; and by the XIVth century, guilds regulated the society, being able to pass bills for example. Hence, a real political power and a fierce competition between the different guilds.
During the XIIIth century, the guilds were fighting over power and wealth, and that is why in 1240 was built the loggia of Orsanmichele by Arnolfo di Combio, a major architect whose work is representative of the Florentine gothic architecture. However, it was used both as a market place and a place of devotion since an idol of the Virgin Mary, inside the loggia, was much visited by pilgrims for it had been the stage of a Christian Miracle, quickly making Orsanmichele a place of dedication rather than a marketplace.
The first half of XIVth century is often considered as being the apogee of Florence: the construction of Santa Maria del Fiore started in 1290, the construction of the Palazzo Vecchio started around the same period of time, showing the wealth and growing empowerment of the city. The second half of the XIVth century was more of a challenge to the city of Florence, yet artistically speaking the Church of Orsanmichele has never stopped evolving since the sculptures of the niches were built until the very beginning of the XVIIth century. That is why we can now consider Orsanmichele as the testimony of the evolution of the Florentine artistic scene, from the late XIIth century to the very beginning of the Baroque period.
The 1337 building was commissioned by the Silk Guild, and built following the plans of the architects Neri di Fiovarante (… – 1374), Benci di Cione (1337-1404), and Francesco Talenti (1300-1369).
Architecture and decor
A) A CHURCH DESIGNED AS A PALACE
One can easily notice that Orsanmichele does not have the regular outline of a Church, as for example Santa Maria Novella, also completed during the XIVth century, that has the classical outline of a Christian cross. Instead, Orsanmichele is rectangular, as a classical loggia was. That can easily be explained by the original purpose of the building: a market place for wheat. Indeed, the place was turned into a Church because of the idol of the Madonna that was very popular and often visited by Pilgrims as well as locals. When the building was reconstructed in 1337, it kept the original basis of the structure and built the Church according to this shape. What actually makes it a Church are the purpose that it was given as well as the Altar and the Tabernacle that can be found inside. Hence, the interior architecture is more that of a church than the exterior architecture.
B) EXTERIOR ARCHITECTURE: THE NICHES
As mentioned previously, the Church of Orsanmichele is especially famous for the fourteen sculptures that decorate its outside walls.
In chronological order, the sculptures appear as follows: The Madonna of the Rose (1399), Simone Ferrucci or Giovanni di Piero Tedesco; Saint Philip (1410-1412), Nanni di Banco; Saint Mark (1411-1413), Donatello; Saint Peter (1413), Donatello; The Four Crowned Saints(c.1413), Nanni di Banco; Saint John the Baptist (1416), Ghiberti; Saint George (1417), Donatello; Saint Eligius (1420), Nanni di Banco; Saint Jacob (1422), Niccolo di Pietro Lamberti; Saint Matthew (1423), Ghiberti; Saint Stephen (1427-1428), Ghiberti; The doubting of Saint Thomas(1465-1466), Verrocchio; Saint John the Evangelist (1515), Baccio da Montelupo; Saint Luke(1601), Giambologna.
The sculptures are either made of marble (for the less rich guilds), or of bronze (for the richest guilds). The material used was representative of the wealth of the Guild, in particular the arti maggiori.
The most recurrent artists are Nanni di Banco (1385-1421), Donatello (1386-1466), and Ghiberti (1381-1455).
In the beginning of the XVth century, in Laudatio Florentinae Urbis (Praise of the City of Florence), Leonardo Bruni confirms the idea of continuity from Antique Rome to Renaissance Florence, as stated by Coluccio Salutati in 1377, saying about Florence that it was “the daughter and the very fiber of Rome”. Nanni di Banco, Donatello, and Ghiberti’s sculptures illustrate the Renaissance equilibrium between this will of being the daughter of Rome and the late Florentine Gothic style.
Therefore, in order to illustrate this mixed artistic influences, one can focus on Nanni di Banco’s Four crowned Saints and Donatello’s Saint George.
THE FOUR CROWNED SAINTS, NANNI DI BANCO
The sculpture of the four saints was commissioned by the Guild of workers in stones and woods, and is made out of marble. The niche itself presents highly Byzantine influences: the upper decorative part can be compared to Flamboyant Gothic Style cathedrals such as the Cathedral of Amiens, built in the XIIIth century. The interior of the niche, especially the upper part, is in cross vaults, which are typical of the Gothic style. The frieze, in the lower part, recalls of Medieval manuscripts in which the Gospels were illustrated with such ornaments. Here, it is representing sculptors in the typical Florentine bottega, allowing to presume that the four saints are giving their consent to what the sculptors are doing in that frieze and, therefore, to all the sculptors in Florence.
However, the subject itself is linked to Antique Rome since the Four Crowned Saints, Claudio, Nicostrato, Sinfronio and Castorio) were roman citizens who had converted to Christianism and had become martyrs after they had refused to sculpt the statue of a Pagan idol.
The plastic treatment is also very linked to that of Ancient times: not only are they wearing roman togas, they are positioned in contrapposto and the drapery of their clothes recalls the treatments of the gowns in Ancient Rome monuments.
Consequently, Nanni di Banco has illustrated the wished continuity between Antique Rome and his contemporary Florence.
Donatello’s Saint George gives a very different impression from the formerly mentioned sculpture of the Crowned Saints. The medieval references are stronger than in Nanni di Banco’s work. Indeed, Saint George was very famous thanks to the XIIIth text, the Golden Legend, in which the episode of Saint George defeating the dragon is related, and more specifically in the Byzantine East. Here, the character is standing straight, there is no contrapposto, and his adornments (shield, sword, military gown) are typically medieval. But here, Saint George is not here to represent the link between Ancient Rome and Florence, it was made to represent Florence’s strength and determination in keeping its hegemony while the city was facing threats from growing neighbor cities, most particularly Naples. The idea behind the Saint George is that of not being afraid in front of enemies, and the Saint’s stature embodies the idea very well: he is standing equally on both legs, but one of his feet is just a little outside the niche, meaning that he is ready to attack; his shield is in front of him, depicting the Saint’s determination of not being attacked; finally, his look shows the idea of a conqueror, who will not be defeated. Anyone passing in front of the sculptures in these times of fear, would find himself wanting to be as strong as Saint George, and that is the idea that Donatello wanted to convey.
In relation to the exterior architecture, the interior is also of rectangular shape. The holes in the wall testify of the time period when the building was a granary: the grains were sent from the second floor to the ground floor for the merchants to sell. The ten external pillars can also be seen from the inside, and frescoes are painted all over them. The two internal pillars are standing in the middle of the room and finally, at the back of the room, stands the presbytery with the Tabernacle of Madonna Delle Grazie (c.1359) by Orcagna, and the Saint Anne Altar (c.1526) by Francesco da Sangallo.
The ceiling is supported by cross vaults of stones and bricks, which create a dual material effect that can also be found – for example – on the facades of other Florentine churches such as Santa Croce, but also on Byzantine or Islamic medieval architecture, once again testifying of the high influence that other medieval architectures have had on the Florentine one. As for the cross vaults, they are typical of Gothic architecture.
THE FRESCOES ON THE PILASTERS
If the vaults and ceiling are also covered in fresco, the paintings on the pilasters are much more atypical since they represent Patron Saints in real life sizes. First of all, the impression that their sizes gives makes the paintings very impressive to the human eye. Most of the works were realized by Jacopo Casentino, yet among other painters. There are thirty-six saints represented in total, and between them are important stylistic differences. Looking at the representation of Saint Bartholomew, the medieval reminiscence is obvious. The saint is in a frontal position, on a blue background, with a golden aura around his head. The representation is clearly in-between medieval and Renaissance – for the painting is less static and the facial expression is a little more precise than on a medieval painting.
Nevertheless, Saint Stephen Promartyr, shows a tridimensional aspect that the former Saint did not have. The warmer colors, the detailed clothing, the contrapposto and the light – as if it were coming from inside the Church and enlightening the Saint – show a painting technique that is closer to that of the Renaissance than to the medieval one. Also, the absence of an aura shows the humanist point of view of the painter: The Saint looks more human, thus allowing the devotees to feel closer to the Saint, hence, closer to the religion itself. Most probably were the two frescoes painted during different periods of time.
Once again, the frescoes illustrate the evolution of the Florentine artistic scene, but this time in painting. It is also relevant to notice that it does not only concern the Florentine arts, but enhances the evolution from Medieval Times to Renaissance: during the Middle-Ages the techniques were not as developed as during the Renaissance (lacking the discoveries of the Antique treaties that allowed painting, sculpture and architecture to evolve), but in terms of religion, the purpose was very different. The painting aimed at making sure the person who stood in front of it understood perfectly its meaning, as a perfect illustration of the religious texts. The Renaissance, with the rise of humanist thinking and the Protestant Reform, was more about putting man in the middle of everything. Therefore, the saints keep their classical iconography but the representation has a scientific approach that there was not in the previous sacred representations.
The presbytery itself is elevated by two small steps, and the ground is made of stones and marble. A third of the surface is covered in three different marbles: white marble from Carrara, black marble from Monferrato and red marble from Monsumanno
Orcagna, or Andrea di Cione di Arcangelo (1308-1368), completed the tabernacle[2]between the years 1352 and 1360. First of all, the structure of the tabernacle is interesting for it recalls that of a Church. A three-part structure, of which the main and central one is a vault overlooked by a dome. This choice is not innocuous, since sanctuaries dedicated to the Virgin Mary are often linked to cupolas, and the tabernacle contains Bernado Daddi’s tryptic panel Madonna and Child with Angels (c. 1346/7). The architectural style is typically flamboyant Gothic, tied by the European impulse of Gothicism architecture as mentioned previously. The decorative elements include animals, minerals, plants, implements, natural phenomenon… for example, seashells are used along with stars, in the center of the vault. These elements are direct references to the Virgin Mary: the shell is the symbol of the Immaculate Conception – and extensively a symbol of birth in general –, just like the snail (present on the friezes) is a reference to the same idea of virginity (folk wisdom considered that snails came from mud and not from procreation). Various other elements are either Christic references or references to the Virgin Mary. It also contains sculpted elements (framed by the seashells) which depict various moments of the life of Mary.
It is interesting to consider the actual placement of the tabernacle according to where the entry now stands. Indeed, the entry to Orsanmichele is on the left-hand side (when facing the presbytery). Thus, the first thing that the spectator sees is the altar and not the tabernacle. However, the grandiose aspect of the latter, and its imposing architecture, immediately attracts the eye towards it. However, the tabernacle was conceived as to receive outdoor lightning since it was conceived when the Church was still an open market place and the walls had not been sealed. Now that it stands in a closed space, the tabernacle can seem a little out of place, especially considering that it stands next to the Altar which is much smaller.
THE ALTAR OF SAINT ANNE, FRANCESCO DA SANGALLO
The Altar was sculpted by Francesco da Sangallo in the first half of the XVIth century. It represents Saint Anne, the Virgin Mary and the Christ. The cult of Saint Anne, in Florence, started after the expulsion of the Duke of Athens in 1343. Here, the sculptor does not only represent the Holy Family, he represents the stages of life. Indeed, Saint Anne is represented as an elderly lady, which is rarely the case in previous representations as one can see on Raphael’s Madonna del cardellino painted in 1507.
Also, the artist made a clear reference to Michelangelo’s Pietà of 1498, for he signed his name on the belt of Saint Anne, as Michelangelo had done on the Virgin Mary’s.
Conclusion
What is to highlight about the Church of Orsanmichele is its capacity to create a link, if not a discussion, between different periods of time and different artists. Indeed, the architectural and decorative evolution of all its elements – both architectural and decorative – allow the spectator to understand the artistic history of Florence.
Architecturally speaking, the building represents the evolution of the city of Florence. Then, even more intensely, its decorative aspect – both interior and exterior – shows the technical evolution in art, as well as the new ideas in thinking that appeared, mostly during the Renaissance period. The presence of elements dating from late Middle-Ages to the very end of the High Renaissance allows one which passes in front of the Church to have a clear overview of the evolution of the artistic scene of Florence. The interior has the same capability.
Thus, the Church of Orsanmichele is a Gothic building of which the architecture is both that of a palace and that of a Church.
Bibliography
- Artusi, L., and S. Gabrielli. Orsanmichele in Firenze. Becocci Firenze., 1982.
- Avery, Charles. Florentine Renaissance Sculpture. Butler and Tanner Ltd, Frome and London, 1987.
- “Italy – Florence in the 14th Century.” Encyclopedia Britannica. Accessed September 22, 2018. https://www.britannica.com/place/Italy.
- Kreytenberg, Gert. Orcagna’s Tabernacle in Orsanmichele, Florence. Harry N. Abrams, Inc., Publishers., n.d.
- “Omeka@CTL | Italy in Crisis: Plague in the 14th Century : Tuscany : The Madonna Delle Grazie and Orcagna’s Tabernacle.” Accessed September 11, 2018. http://ctl.w3.uvm.edu/omeka/exhibits/show/plague/tuscany/tus-madonna.
- “Orsanmichele Church and Museum – Florence.” Accessed September 11, 2018. http://www.museumsinflorence.com/musei/orsanmichele.html.
- Richard Turner, A. Renaissance Florence, The Invention of a New Art. Perspectives Prentice Hall, Inc., 1997.
La storia è quella dell'avventura di alcuni speleologi che, sotto al piccolo centro storico di Orvieto, proprio dentro alla grande Rupe così propensa all'instabilità, hanno ritrovato un incredibile mondo sotterraneo che era stato scavato, utilizzato e poi dimenticato: un oscuro labirinto articolato in oltre 1200 tra grotte, cunicoli, pozzi, cisterne, creato dall'uomo, picconata dopo picconata, in quasi tre millenni di ostinato e continuo lavoro.
Tutto iniziò alla fine degli anni 70, quando una frana di grandi proporzioni assestò un bel morso nella Rupe orvietana, a poche centinaia di metri dal celeberrimo Duomo. Ultimo, e più grave, evento causato dal dissesto idrogeologico che minava la stabilità della Rupe, la frana allarmò il mondo intero, preoccupato per la sopravvivenza di Orvieto e delle sue opere d'arte. Ma incuriosì lo sparuto ed agguerrito gruppetto di speleologi locali, già attenti ad una sorta di leggenda metropolitana che, di certo enfatizzando brandelli di una realtà che la memoria storica cittadina non riusciva più a ricordare coerentemente, mitizzava una Orvieto "tutta vuota, sotto". La stessa Rupe mostrava, in alcune delle sua alte e strapiombanti pareti, misteriose aperture, finestrature dai profili irregolari, occhiaie vuote e buie che sottintendevano sotterranei inspiegabili e inesplorati e che, come i cosmici buchi neri, furono fonte di irresistibile attrazione per gli speleologi orvietani.
La riscoperta dell'incredibile realtà sotterranea iniziò proprio da questi aerei pertugi. Assicurate le corde agli alberi dei giardini e degli orti che coronano quasi tutto il perimetro superiore della città (e, in loro mancanza, ai semiassi delle auto), gli speleologi iniziarono a calarsi lungo la sfaccettata Rupe. Emozione. Emozione si può definire, in una parola, la risultante delle sensazioni che caratterizzò le esplorazioni. Emozione, prima di tutto, per gli spazi aperti in cui avvenivano le discese: gli speleologi erano sì abituati all'utilizzo impavido delle corde per superare grandi altezze, ma nell'ambiente angusto delle grotte, dove la vista è limitata al frammento di spazio rubato dall'acetilene all'oscurità e il buio stesso bandisce benignamente ogni vertigine. Qui invece si trattava di abituarsi improvvisamente ad operare all'aria aperta, con lo sguardo libero di spaziare per chilometri e la corda che, in quell'immensità, non era più tale, ma solo un filo sottile sottile... e mente chi nega di aver sentito, almeno per le prime volte, un po' di batticuore. Emozione, soprattutto, per ciò che appariva una volta penetrati nelle grotte rupestri. Stanze squadrate, collegate tra loro da gallerie e illuminate da piccole finestre, si susseguivano per decine di metri su più piani sovrapposti uniti da brevi pozzetti e scivoli. Nelle pareti di fondo, quelle più interne, si aprivano angusti cunicoli che penetravano verso il cuore della Rupe e permettevano a stento il passaggio di una persona carponi o distesa, ma solo per pochi metri, perchè invariabilmente qualche frana poneva irrisolvibili interrogativi sulla loro destinazione. Gli anni avevano ricoperto i pavimenti di uno spesso strato di finissima polvere di pozzolana; ad ogni passo si alzava, rimaneva sospesa in aria immobile, rigata a volte da obliqui raggi di sole che cadevano dalle finestrelle, conferendo a quelle singolari grotte un aspetto che evocava suggestioni quasi magiche. Ma le pareti di quelle stanze, più che il resto, davano l'impressione di essere entrati in una dimensione irreale, in un mondo che era solo un'inquietante imitazione di quello di superficie: migliaia di piccole nicchie cubiche profonde circa un palmo le ricoprivano interamente, senza soluzione di continuità, dai soffitti ai pavimenti. Un'immagine che richiamava alla mente le parole fatte dire da Jorge Luis Borges al protagonista del racconto "L'immortale": "Questo palazzo è opera degli dei" pensai in un primo momento. Esplorai gl'inabitati recinti e corressi: "Gli dei che lo edificarono sono morti". Notai le sue stranezze e dissi: "Gli dei che lo edificarono erano pazzi". Nessun dio aveva, naturalmente, lavorato a quell'opera e, naturalmente, nessun pazzo. Tutto invece rispondeva a precisi criteri di razionale sfruttamento del sottosuolo. Gli speleologi avevano riscoperto quegli apprestamenti sotterranei noti col nome di "colombari", scavati dagli antichi orvietani appena dietro le pareti esterne della Rupe per allevare, nelle piccole nicchie appositamente realizzate, i piccioni, tuttora piatto classico della cucina locale.
L'intuizione dei ricercatori iniziava dunque a trovare conferma e la dava anche alla diceria popolare che voleva Orvieto "tutta vuota, sotto". In effetti, il sottosuolo cittadino cominciava a palesarsi e premiava i ricercatori con una tale quantità di grotte da rendere necessario, parallelamente all'attività di esplorazione, un attento lavoro di catalogazione che suddivise le cavità scoperte per tipo, periodo di scavo ed altri parametri che resero razionale l'archiviazione dei dati raccolti. A questo punto agli speleologi si unirono gli archeologi e l'abitato continuò a rivelare i suoi incredibili recessi sotterranei, vere radici su cui la città era cresciuta e si era stratificata e che il tempo aveva fatto dimenticare. Complessivamente le grotte scoperte superano ormai il numero di 1200, ma il dato numerico, sebbene stupefacente, non è comunque che un'arida quantificazione del lavoro svolto. Non racconta cosa si prova, ad esempio, a percorrere un angusto cunicolo che porta ad un pozzo dove il raggio della torcia elettrica si perde senza trovare il fondo. E allora giù una corda, ed inizia una verticale discesa in un budello di poco più di un metro di diametro che termina dopo trentacinque metri su un cumulo di detriti gettati chissà quando, chissà da chi. A metà discesa due cunicoli scompaiono nel buio. Un breve pendolo, una sotterranea singolare altalena per raggiungerli ed esplorarli, ma terminano dopo poco. Gli antichi scavatori non hanno proseguito nel loro estenuante lavoro sotterraneo,. Perchè? Non c'è risposta. E sopra, la città vive la sua vita quotidiana ignorando che proprio lì sotto, a pochi metri di profondità, un ricercatore armato di casco striscia attraverso un passaggio aperto da un piccolo crollo, sfiora con prudenza massi instabili e preoccupanti, si affaccia, illuminandola di nuovo dopo secoli di oscurità, in una cisterna e rivede, al chiarore giallo dell'acetilene, i grossi conci di tufo abilmente sovrapposti dagli Etruschi nel V secolo a.C. L'opera congiunta degli speleologi e degli archeologi ha permesso il ritrovamento delle grotte del sottosuolo di Orvieto, nonchè lo studio sistematico e scientifico dei dati reperiti.
La Rupe, colonizzata già a partire dal IX secolo a.C., vide poi prosperare un'importante città etrusca, l'antica Velzna. A questo periodo risalgono i primi ipogei scavati dall'uomo alla ricerca dell'acqua, bene insostituibile in una città che, inespugnabile per le insuperabili pareti di roccia che la difendevano, doveva essere in grado di resistere agli assedi. Purtroppo sull'alto pianoro della Rupe orvietana l'acqua è totalmente assente. Da questa carenza nacque l'esigenza di scavare pozzi. Molto profondi, sono tutti a sezione rettangolare e non misurano più di 80 per 120 centimetri. Così angusti, precipitano a piombo per decine di metri alla ricerca delle vene sotterranee. Le due pareti più lunghe sono segnate, con regolare scansione, da piccole tacche, chiamate "pedarole", che permettevano di muoversi all'interno di questi condotti verticali. E lo permettono ancora oggi: gli speleologi, appoggiate le punte dei piedi nelle pedarole, sono scesi e risaliti, sapendo con emozione di ripetere, per un inevitabile automatismo imposto dalle caratteristiche del pozzo, movimenti già mille volte ripetuti, esattamente nello stesso punto, da altri uomini venticinque secoli prima. Gli Etruschi realizzarono anche delle cisterne per la conservazione dell'acqua piovana, nonchè una estesa rete di cunicoli per il suo convogliamento. Basti dire che grazie a tutto ciò, Velzna riuscì a raggiungere l'autosufficienza per quanto concerneva l'approvvigionamento idrico, tant'è che cadde nelle mani di Roma, nel 264 a.C., solo dopo aver resistito ad un assedio che durò più di due anni. Nei secoli successivi gli scavi continuarono. Il sottosuolo della città ha rivelato cave enormi da cui vennero estratte tonnellate di pozzolana, pozzi e cisterne di ogni epoca e dimensione, gallerie, cantine, rifugi, pozzi-butto che ancora restituiscono esempi frammentari di raffinata ceramica medievale e rinascimentale. A volte, la scoperta di alcuni ipogei di grande importanza è un regalo del caso, come, ad esempio, quando venne trovato ciò che ora è noto come "Il Pozzo della Cava". Il proprietario di una tipica trattoria del quartiere medievale notò che una muratura che si trovava nella cantina del locale, e che sembrava una semplice opera di sostegno, dava cenni di cedimento. Rimosso un blocchetto di tufo scoprì... il vuoto! Al di là del vecchio muro non c'era niente! Gli speleologi, prontamente giunti appena sentita voce della scoperta, filati metri e metri di corda oltre il piccolo passaggio apertosi, si calarono nell'oscurità, non senza un preventivo battibecco circa le priorità di discesa che vennero, tuttavia, cavallerescamente stabilite a gomitate. Un grande pozzo li accolse ospitandoli sul suo fondo coperto di detriti, quasi trenta metri più in basso. Si scoprì anche che la parete del pozzo era segnata, per tutta la sua altezza, dalla traccia di un pozzetto con pedarole, tipico del periodo etrusco. Ma le sorprese non erano ancora finite. Dopo alcuni anni, il proprietario decise di liberare il fondo del pozzo dai detriti, invogliato anche dal ritrovamento di documenti attestanti la presenza dell'acqua almeno fino al XVII secolo. Dopo pochi metri di scavo gli speleologi si trovarono di fronte ad una piccola galleria (ad oltre 35 metri di profondità!), occlusa dopo una quindicina di metri da una grande quantità di argilla che impedì la prosecuzione dell'esplorazione, disegnando un nuovo grande punto interrogativo nella mappa delle ricerche sotterranee orvietane.
