Journal of Volcanology and Geothermal Research 178 (2008) 347–358

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Vesuvius: A historical approach to the 1631 eruption “cold data” from the analysis ofthree contemporary treatises

Emanuela GuidoboniIstituto Nazionale di Geofisica e Vulcanologia, Sezione di Bologna, via Donato Creti, 12, 40128 Bologna, Italy

E-mail address: guidoboni@bo.ingv.it.

0377-0273/$ – see front matter © 2008 Elsevier B.V. Aldoi:10.1016/j.jvolgeores.2008.09.020

a b s t r a c t

a r t i c l e i n f o

Article history:

The 1631 Vesuvius eruption Received 15 March 2007Accepted 26 September 2008Available online 10 October 2008

Keywords:historical volcanologyVesuvius1631 eruption chronologyprecursorstreatises

is one of its best known and most studied of its type. However, the historicalapproach performed within the framework of the Exploris project highlighted new evidence from previouslyunused or unknown historical sources. These consist of three treatises that were contemporary to the event;although written in Latin, they have been fully translated and analysed. To guarantee systematic use andopen access to the large amount of information they contain, they have been provided as a small database.These treatises have provided new information on phenomena that preceded and accompanied the eruptionof 1631, making possible the formation of a complex chronological profile, starting from around 6 monthsbefore the eruption. The anthropic impact is also outlined. The method applied has produced a chronology of“cold data”, which are not interpreted from the volcanological standpoint, but only derived directly from theanalysed history and sequence of the texts. The analysis of the three treatises has not, however, solved all ofthe problems connected with the detailed knowledge of the event in 1631. Indeed, problems of two kindspersist: a) linguistic correspondence between the volcanological terms of today and those used in the texts;b) the lack of precision of the measures indicated. Here, the main results obtained from this analysis methodare presented, along with a discussion of their limitations and some new perspectives.

© 2008 Elsevier B.V. All rights reserved.

1. Introduction

On 16 December, 1631, a violent eruption of Vesuvius began, at theend of a long period of repose that had led people to forget the dangerof this volcano. As is well known (Rosi et al., 1993; Rolandi et al., 1993;Marturano and Scaramella, 1998), the eruption lasted for several daysin its most acute phase, which caused over a thousand deaths as wellas major economic damage to the villages of the Vesuvius area. Theeruption also left indelible signs on the landscape (e.g. changes in thecoastline, the profile of the volcano), and also on the culture of the day,which suddenly felt more vulnerable and weak in confronting thisvolcanic activity.

This eruption ended completely only after a few years, but byJanuary 1632 a number of intellectuals from Naples and other places,were already engaged in drafting reports and treatises to describe andinterpret that extraordinary reawakening of Vesuvius. Indeed,between 1632 and 1634, numerous pamphlets, notices, letters andreports were published, along with treatises, some of which werewritten in Italian, others in Latin, and one in Spanish. This largecollection of edited works was already listed in the Vesuvianbibliography of Furchheim (1897), which was variously cited in thescientific works starting from Alfano (1924) and Alfano and Fried-länder (1929), and integrated by Cerbai and Principe (1996). The aim

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of the present study was to develop a new critical reading of the“apparently” known texts, that have been often cited, but notanalysed. The volcanological literature of the last 40 years has indeedconcentrated more on the treatises and the reports drafted in Italian,sometimes also citing texts in Latin, but without actually consultingthem.

For this study, three contemporary treaties written in Latin werechosen, which owing to the difficulty of the language, have not beenadequately taken into consideration previously.

2. The methods and materials of the study: the role of “cold”historical data

The aim of this study was two-fold:

i) to attempt to reconstruct the eruption scenario as described by thewitnesses in a new way, that has not been analysed previously, toprovide new data for volcanologists;

ii) to attempt to reconstruct a chronology inferred from these texts,with the separation of the textual and conceptual analyses of thetreatises from our present-day scientific knowledge.

This method is aimed at providing chronological succession of“cold” data: this is not intended in the sense of “objective” data, but inthe sense of “preinterpreted” data from a volcanological point of view.Indeed, I believe that between the historical sources and theirvolcanological interpretation there is the need for an explanatory,

348 E. Guidoboni / Journal of Volcanology and Geothermal Research 178 (2008) 347–358

and easily checked, phase, explained from an exclusively critical,philological and historical point of view. In my opinion, this kind ofexplanatory interface should, on the one hand, favour increasedtransparency on the part of the volcanologists in the interpretation ofhistorical data; on the other hand, it should make possible moreinterpretations and uses of the same data, although withoutnecessarily avoiding critical problems relative to the interpretationof words, measures, sequences and durations, for example.

In its present state, the volcanological literature of events in thepast instead provides an already interpreted version. More like a“story of a story” rather than scientific use of the historical data, thistype of analysis can create a closed circle, in which elements alreadynoted and understood tend to be selected.

A small workgroup of exclusively historians and philologists hastherefore examined the three texts. The study lasted for over a year. Thedescriptions of the activity of Vesuvius (and of other volcanoes in theMediterranean area) in the treatises of the last four centuries areespecially rich in detail, and are inserted within a lengthy chronologicaldevelopment. Most of the phenomena described in these treatises canthus be pinpointed in time and in geographical space, and hence beanalysed as a fully fledged sequence of cold data before any scientificinterpretation, as canonly result fromahistoric andphilological analysis.

The separation of the two levels, i.e. historical and volcanological,which has instead has been followed here, obviously does not comewithout its surprises, as well as some problems, as it lays bare someunresolved aspects (and also at times some that are hard to resolve),some possible contradictions between the examined texts, or neglectedelements that are of primary importance. As compared with theknowledge already gained in the literature, this appears to be a morerealistic set of data, although also in some ways more problematic foranyone who has to interpret this data within the volcanological field.

The results presented here constitute a newway of using historicaldata in volcanology, which was applied for the first time within theExploris project.

3. The treatises examined and their cultural context

A preliminary analysis of the available choices suggested one ofthree treatises: Carafa (1632), Mascolo (1634) and Varone (1634).These are only partially known and have been little used byvolcanologists as they were written in Latin; the first two havecertainly been cited, while the third has remained virtually unknown.

These three treatises are positionedwithin the Latin language usedby the witnesses to the 1631 eruption. The liveliness and theimmediacy of the descriptions made by these authors is accompaniedby a substantial literary erudition, which was typical of theecclesiastics and the men of law of those times. The authors werecommitted to describing and explaining everything they had observedbefore, during and after the 1631 eruption. This descriptive activitywasmade, as can be imagined, within the cognitive frameworks of theday, an element that demanded an all but superficial knowledge of thetheories as to the origins of volcanoes and earthquakes of those times.

In all three treatises, the description of the Vesuvius eruption in1631 is preceded by dozens of pages of philological, etymological andhistorical disquisitions (often a discouragement for the volcanolo-gists), which are an example of how the culture of the day addressedthese great natural events. The most important element in theexplanation of the natural phenomenawas still the preponderant roleof the tradition of the natural philosophers that had preceded them.So it can be said that there was a knowledge that ‘reiterated’ itself,with very few variants, thereby forming a compact self-referentialsystem. The knowledge of this context continually interacts with the

Fig. 1. Views of Vesuvius A) before and B) after the 1631 eruption, from engravings by Nicolfamous images almost became icons of that great event in the Europe of the day.

description of the events and it is an important background thatcannot be ignored by those who analyse the texts.

Each of the three treatises has a section concerning the historicalactivity of Vesuvius prior to 1631. The three authors recall prioreruptions of Vesuvius from very similar sources and literary traditionsthat are not totally independent, supporting them with their ownpersonal classical culture, and forming some proto-catalogues, whichwere then at the root of the current catalogues. However, if the eruptionof 79ADwasmore or less known about from the ancient sources, for themedieval period their data appear to be very scanty. This is also becausein the 17th century there was a scarce availability of printed medievalsources, and such texts were mostly manuscripts lying in monasticlibraries or in collections of scholars and aristocrats.

In the 17th century, many texts of a naturalist type (e.g. essays andtreatises in early physics, medicine, astrology), and above all of atheoretical character, were written in Latin. However, Italian was alsoused for texts in major research: indeed, as is well known, the DialogueConcerning the Two Chief World Systems of Galileo was published inItalian, in Florence, in the very sameyear of 1632 (Galilei,1632). Then, inOctober that year the dramatic events of the inquisition trial of Galileostarted, an event that was held to be the start of modern science, andunderstood as research independent of theology. But the parallelismwith the three treatises examined is only chronological: indeed, fromthe standpoint of scientific thought, these three Neapolitan treatisesabout the 1631 eruption constitute an example of pre-Galileandescriptions of nature, which was then still the exclusive domain ofecclesiastics and theologians, or of medical practitioners and physicistswhowere still searching for confirmation of ancient natural philosophy.

These three texts indeed show how in thewidespread knowledge ofthe day the theories as to the causes of the natural phenomena werepractically closed to Aristotelian opinions and theories, which wereassumed and elaborated by medieval philosophy, and coded in theScholastic system. Our three authors ignore the great novelty that the16th century naturalist thinking had instead articulated,with the doubtscast upon the Aristotelian interpretation of Nature. Mathematicalphysicists and naturalists, like Georg Bauer, Agricola (1494–1555), orphilosophers like Bernardino Telesio (1509–1588) and Giordano Bruno(1548–1600) started an intellectual break-away movement towards anewobservationof nature and its phenomena. Our three authors are notthe representativesof that restlessworld of thephilosophical researcher,but rather of the closedhorizons of intellectual conformism that in thoseyears was typical of church culture.

However, when the three are treatises examined, albeit within thelimits of the cultural framework and the interests of the authors, theyaccurately describe the phenomena that had preceded and accom-panied the 1631 eruption, and the evolution of the events witnesseddirectly or reported by a collation of witness reports that they feltcould be trusted. The treatise by Mascolo, for example, also containstwo famous images of Vesuvius, before and during the 1631 eruption,which in the Europe of the day almost became an icon of that greatevent (Fig. 1A and B). The three treatises also reveal the devastatingeffects upon the Vesuvius area and the social responses that arose inthe very early phases after the catastrophe. However, for these socialand economic aspects there are other numerous coeval documents,more important and authoritative than the treatises, in the ecclesias-tic, private and public administration (today in historic archives), thatdo not fall without the scope of the present study.

4. The authors of the three treatises

As indicated above, the authors of these three treatises were typicalspokesmen of the Neapolitan intelligentsia in the ecclesiastic and

as Perrey, Table 1, included in the treatise by G.B. Mascolo (1634) examined here. These

349E. Guidoboni / Journal of Volcanology and Geothermal Research 178 (2008) 347–358

Table 1Example of a comparison between the current terms and those in Latin from the threetreatises examined. Listed here are some “technical” terms most used today within thevolcanological scope and their possible equivalents used in the three treatisesexamined. For each term the Author of the treatise and the page number is indicated,understood as the first occurrence of the term in the examined works. Legend: C 1 =Carafa p. 1; M 2=Mascolo p. 2; V 3=Varone p. 3

English Latin and literal meanings Source

Volcano mons [mount] C 4; M 3; V 2mons ignivomus [fire-spewing mount] M 155mons ignigenus [fire-producing mount] V 64mons igniferus [fire-bearing mount] V 120Vulcanius [(mount) of Volcano] V 64

Vent/bocca vorago [abyss] C 8; M 18; V 119barathrum [precipice] C 9cavernae [caves] C 10; M 11viscera [bowels] C 11; M 13; V 64os [mouth C 8; M 15os ignem evomens [fire-spewing mouth] C 7faux [maw] C 9; M 219

Crater crater [crater] C 8; M 18; V 29vorago [abyss] C 12; M 7; V 123hiatus [aperture] C 13; M 3; V 82hiantis barathri fauces [maw ofthe wide-open precipice]

C 9

Conduit caminus [chimney] M 3uter [uterus] M 25; V 2

Rumbling mugitus [bellowing] C 10; M 275; V175fragor [din] C 10; M 275; V361sonitus [sound] C 14; M 3; V 118murmur [rumbling] C 16; M 11fremitus [rustling] M 3strepitus [clanging] C 89; M 156; V 45rumor [noise] C 15; M 4; V 65

Earthquake terraemotus [earthquake] C 9; M 19; V 79motus [movement] C 10; M 8; V 58tremor [tremor] C 11[terrae] concussi [shaking (of the earth)] C 9; M 2; V 119

Eruption conflagratio [conflagration] C 5; M 34; V 3incendium [blaze] C 6; M 2; V 2eruptio [eruption] C 9; M 283; V 4

Lava torrentes ignei? [igneous torrents] C 42; M 17; V 253;torrentes ignis? [torrents of fire] M 15torrentes flammarum? [torrents of flames] M 15

Magma – –

Ash cinis [ash] C 6; M 1; V 133arena [sand] C 28; M 11; V 159

Cloud nube [cloud] C 12; M 3; V 139nebula [cloud] V 159

Gas – C 11; M 155; V 63Exhalation exhalatio [exhalare] [emission] C 11; M 155; V 63

spiritus [spirit (blowing)] C 11; M 8; V 63spiritus inflammatu [inflamed s.] M 70halitus [breath] C 11; M 12; V 64halitus igneus [igneous breathing] M 12; V 64afflatus [blowing, breathing] M 21

Gas/Smoke fumus [smoke] C 10; M 3; V 84exhalationes fumosae; exhalationesfumidae [smoky emissions]

C 44; C 87

fumidi vortices [vortex of smoke] M 14Vapour phreatic

eruptionvapo [steam] C 13; M 21; V 196vapor igneus [igneous steam] M 21; V 196

Piroclastic flow torrentes igniti cineris? [torrents of fiery ash] C 30Lahar torrentes liquati cineris?

[torrents of melted ash]C 31

fluvius cineris [river of ash] C 31fluidus cinis [fluid ash] C 38

Pumice pumex [pumice] C 29; M 219

350 E. Guidoboni / Journal of Volcanology and Geothermal Research 178 (2008) 347–358

religious spheres. All three were erudite, cultured men, and author-itative first-hand witnesses of the eruption, as they saw it in person.

4.1. Gregorio Carafa

Carlo Marcello (later Gregorio) Carafa was born in Naples in 1588,the son of Marzio Carafa and Faustina, daughter of FabrizioSammarco, Baron of Rocca d'Evandro. Carafa undertook a scholasticpath that was typical of his elevated social status, and was thereforeof high profile. He dedicated himself to the study of theology andphilosophy, and joined the Teatini fathers in the house of San PaoloMaggiore of Naples, where he took his vows on 18 November, 1606,taking the name of Gregorio. Still in the house of the Teatini of Naples,he held the Chair of Philosophy for 3 years, and that of theology forsix. The fame he acquired among his contemporaries as a theologian,preacher and man of great culture, as well as the position of hisfamily, the support of the Viceroy of Naples, and therefore of theEmperor Philip 4th of Spain, meant that Carafa reached the highestpositions in his Order: he was the chief of the Teatini from 1641 to1643, and the following year he was elected as the 12th general Headof the Order; in 1646 he was reconfirmed. He was a firm supporter ofecclesiastical jurisprudence.

On 24 August, 1648, he was elected Bishop of Cassano in Calabria;on 23 June, 1664, he became Archbishop of Salerno. He became theextraordinary diplomatic attaché of Philip 4th of Spain to PopeInnocence 10th and held several other diplomatic offices, althoughperhaps of an exclusively honorary nature. He died in Salerno, on 23February, 1675.

4.2. Giovanni Battista Mascolo

Giovanni BattistaMascolowas born in Naples on 24 June,1583, andbecame a Jesuit in 1598. He taught theology and philosophy at theCollege of his Order, of which he was Rector for some time;subsequently, for 17 years, he held a school of rhetoric at his home.Famous as a good Latinist, he wrote elegant verses in Latin, with a richand flowery style. Pope Urban 8th, who held him in high esteem,madehim several career offers, but being of modest and reserved character,Mascolo always refused. His works range across several topics. He diedof the plague in Naples on 20 July, 1656.

4.3. Salvatore Varone

There is very little information available about Salvatore Varone.He was born in Cinquefrondi (Reggio Calabria) in 1593. He joined theCompany of Jesus on 7 October, 1612; he taught grammar, thehumanities and rhetoric, and for six years, scholastic theology andmorals. He was famed as a very learned intellectual, and twomanuscripts in Italian of a rhetorical nature have been attributed tohim. In the period of the Vesuvius eruption in 1631, Varone wasstaying at Portici, and he was thus an eye-witness to the wholeeruption. His treatise was written in full maturity, probably usingsome of his previously unpublished works. He died in Barletta on 5January, 1648.

5. Textual analysis: from the terms to the meanings

One of themost interesting aspects brought to light by this study isperhaps that of the analysis of the terms used in the treatises. Thelinguistic aspect is relevant to the volcanological interpretation ofthese treatises, because some misreading may easily be possible, fortwo main reasons:

i) Latin has some false analogies with Italian, the language-mediumtowards English, and the volcanologists who earlier analysed theliterature of the 1631 eruption were mostly Italians;

ii) some of the terms that are commonly used in volcanology today,such as lava, magma and pyroclastic flow, did not have directequivalents either in the Italian of the times, nor in Latin.

The term lava, for example, appears to be used for the first timeonly in 1663 (see Cortellazzo and Zolli, 1983, p. 656). Again, in 1779,lava meant “a liquefied stone-like substance that is put into

351E. Guidoboni / Journal of Volcanology and Geothermal Research 178 (2008) 347–358

movement” (una liquefatta lapidea sostanza che è messa in movi-mento, Spallanzani, 1779). According to Cortellazzo and Zolli, theorigin of the word lava is Neapolitan, being derived from the Latinlabe (to flow), with the main meaning relating to a torrent ofrainwater. In Sicilian, a language often used in the past to describeeruptions of Mount Etna, the word lavina refers to stream, and la-vinaru to a large torrent canal. The meaning of “volcanic flow” laterprevailed over that of torrent or landslide. Without delving deeperinto the etymology and the use of this term, the interpretativeproblem posed by the three treatises examined is the following:does the fact that the term lava had never been used, nor could ithave been by then, mean that the lava of the 1631 eruption did notexist? From the linguistic standpoint, we cannot claim that therewas no lava just because it was not specifically named as such;instead, the words or the replacement paraphrases must beanalysed. In contrast, the more recent stratigraphic dating byPrincipe et al. (2004) excluded the presence of lava in the 1631eruption: the authors discuss a variety of evidence in detail (notonly paleomagnetic). The different lavas that have been dated to1631 (Gialanella et al., 1993; Rolandi et al., 1993) have beenattributed by Principe et al. (2004) to eruptions of the medieval orpost-1631 period.

From the historical and linguistic point of view, it may be useful torecall how in the 17th century there was a lack of scientific language

Table 2Vesuvius, 1631: from the summer to December 16th 4.00–5.00°h UT. Legend. The numbernotwithstanding precise indications by the authors. ex: 1119 22=November,19th, hours 22UT. Tor dubious date. numbers in italics = day and/or hours “contained” in the time range indicated inday/s h = hour/s. c. = circa

Date or chronological range Duration Time beforeeruption

Source Summary of the descriptio

m d h

Summer/ 08 ? 1 m ? c. 4 m V Fires visible at night at pre09 01 — – 09 10 — 11 d c.3 m 15 d C Lowering of the ground; la09 01 — – 12 16 05 3 m 15 d 3 m 15 d V Considerable anomalous re10 01 — – 11 30 — 2 m 2 m 15 d V Underground noises (from11 19 22 – 11 20 07 9 h 27 d V Rough seas; moderate seis12 01 ? – c. 18 d ? V Emissions, with effects on11 28 — – 12 02 — 5 d 18 d V Darkening and variation in

rock (eastern slope); major11 30 — ? 5 d c. 16 d ? V Loud noises in the Vesuviu12 07 17 – 12 08 17 1 d 10 d V C M Moderate seismic activity

Herculaneum for some day12 08 17 – 12 09 17 1 d 9 d V Underground noises in the12 08 17 – 12 15 — 8 d 9 d V C M Underground noises (Vesu12 09 — [8 d before] – 8 d V Underground noises and th12 09 — – 12 15 — 7 d 8 d V Restlessness among the do

emissions of hot vapours (12 10 — – 12 15 — 6 d 7 d V Glowing, fiery emissions (f12 10 — – 12 15 21 6 d 7 d V Tranquillity of the air (Ves12 11 17 – 12 13 17 3 d 6 d V Moderate seismic activity12 13 — – 12 16 — – 3 d C Darkening of the waters of12 13 — – 12 15 20 2 d 5 d C Tranquillity of the air in th12 14 17 – 12 15 21 1 d 4 h 1 d 11 h V Tranquillity of the air and

coastal area of Vesuvius12 15 20 – 12 16 01 5 h 8 h V Calm sea (coastal area)12 15 20 – 12 16 04 8 h 8 h V C M Repeated seismic activity f12 15 20 – 12 16 05 8 h 8 h V Restlessness among the do

seismic activity (30 shocks12 15 20 – 12 16 07 2 d 8 h M Intense and repeated seism12 15 21 – — — — 7 h 7 h V Underground noises and se12 16 04 – — — — ? c. 1 h C Seismic activity; opening o

just above the path that gocloser to the one facing At

12 16 04 – 12 16 05 c. 1 h c. 1 h V Very loud underground noand the coast facing the mnoises in the Atria; intenseon the eastern slope, seaw

12 16 04 – 12 16 05 c. 1 h c. 1 h V C M Fiery emissions; thunder, uof a cloud (Vesuvius area),

12 16 05 ERUPTION V Smoke emissions; loud uncloud emission reaching ab

suited to describing the parts of the volcano and its activity with termsthat had an univocal meaning, which often makes the recognition ofthe phenomenological reality that their contemporaries describedrather problematic. Suffice it to recall, for example, that to indicate thelavas of Etna erupting in 1669, the mathematician Giovanni AlfonsoBorelli (1670), the first scientist to monitor a volcano and who was apart of the Galilean school, used terms such as: river of fire (flumenignitus), torrent of fire (torrens ignitus), profusion of fire (profluviumignis), and other similar ones, which we again find in the threetreatises examined. This does not necessarily mean that the “rivers offire” of Vesuvius in 1631 were lavas such as those of Etna in 1669.However, it is the use of terms that were the same or similar indifferent volcanological contexts that indicated the need to carry out avery careful and attentive identification of the terms in the currentvolcanological lexis.

Making an intermediate phase explicit to the scientific user, inwhich the original words are preserved, may perhaps avoid a type ofcircular thinking between the use of historical data and volcanologicalinterpretations. Perhaps, it would be useful in the first instance topreserve the original linguistic form, and then only subsequently,through paraphrasing and noting the linguistic context that theauthors themselves outline, to identify the present-day equivalentterm. We have thus attempted to provide a cold lexis also from thepoint of view of word meanings, which we have not initially

s indicate in succession: month day and hour; the time is approximated to the hour,he names of the villages are those currently in use. – : indicatesmissing data. ? = uncertainthe preceding box, so the phenomena described constitute a specification.m = mount d =

n

sent-day Erculano (Resina in the texts) eastern slopes of the volcanondslides; ground faulting; smoke emissions; fiery emissions (north-eastern slope)stlessness among the domestic animals; flight of wild animals from the Vesuvius areaPortici)mic activity in the coastal region of Vesuviusthe herbaceous vegetation [wilting] (Vesuvius area)the water chemistry [salinity] (Vesuvius area); collapse of a great overhanginguplifting of the ground - (slopes, particularly western)s areain the Vesuvius area; underground noises: in the Vesuvius area, and atswestern and south-western slopes of Vesuviusvius area; underground noises (Herculaneum and Vesuvius area)under in the Vesuvius areamestic animals in the Vesuvius area;Small uplifting of the ground;Vesuvius area)rom the central crater; at Herculaneum)uvius area); calm sea (sea facing the Vesuvius area)(Vesuvius area)the wells (Vesuvius area)e area of Vesuvius and in Naplesrestlessness of the animals in the Vesuvius area, calm sea in the

elt at Naples and in the Vesuvius area, for a range of c. 7.380 kmmestic animals (Vesuvius area, from Portici); moderate and repeated); underground noises – Vesuvius areaic activity in the area of Vesuvius and Naplesismic activity – Vesuvius areaf faults and landslides; landslides between the Atria and the summit of the Veolo,es from Atria and circles the Veolo, in the middle of the mountain's slopes,riaises in the Vesuvius area, ebbing of the sea in the Gulf of Naples, between Pozzuoliouth of the River Sarno; earthquakes, landslides, ground faulting; loud undergroundsmoke emissions; fiery emissions; rock expulsion (from the central crater,

ards)nderground noises and lightening, rock expulsion, ash and smog, emissionviolent seismic activityderground noises; ground faulting; opening of a large chasm;out 37 km in height; haze (from the fracture appearing in the Atria)

Table 3Vesuvius activity: from 1631, December 16, h. 05 to December 18. See legend in Table 2

Date chronologicalrange

Duration Source Summary of the description

M d h

12 16 — – 12 18 — 2 d V Hurling of rocks and lapillus; obstructions of the waterways and subsequent overflowing; eruptions of ‘fire’from the central crater, across a range of c. 9.225 km, with particular intensity on the northern slope, as far as Puglia

12 16 05 – 12 16 — ? C Fiery gas emissions, underground noises and lightning, ash and dust, emission of a cloud, violent seismic activity andopening of a new eruptive mouth (from the crevasse that opened in the Atria)

M Seismic activity; underground noises; thunder; fiery emission; cloud (Vesuvius area).12 16 05 – 12 16 07 2 h C Strong underground noises (Vesuvius area)12 16 05 – 12 22 — 7 d C Less frequent and less intense underground noises (Vesuvius area)12 16 05 – 12 18 — 2 d C Lowering of the ground owing to the collapse of the wall: Mount Veolo (central crater) lowered by about 450 m.12 16 05 – 12 18 — 2 d V Moderate and unceasing seismic activity in Campania; rocks hurled at Torre del Greco (Herculaneum),

eruptions of fire at Boscoreale (Boschi)12 16 05 – — — — ? V M Smoke emissions; strong underground noises; cracking of the ground; opening of a new eruptive mouth

(western side of the crater); emission of a cloud that reaches around 37 km in height; darkness from thefissure opening in the Atria

12 16 05 – 12 16 08 3 h V Cloud; suspension of ash and dust; smog; warm and sulphurous emissions (Vesuvius area)12 16 07 – 12 17 05 22 h M Smog; raining ash; cloud; thunder; lightening; fire emissions; raining sand and ash; hurling of fiery rocks; sulphurous emissions12 16 07 – 12 17 — 1 d V M Moderate seismic activity (Vesuvius area; Naples)12 16 08 – — — — ? V Lightning and thunder coming from a cloud of the crater?4; seismic activity; underground noises (Portici, Villa Nava,

Torre del Greco, Ercolano) raining ash; dust suspension; darkness (Portici, Villa Nava, Torre del Greco, Herculaneum)12 16 08 – 12 16 12 4 h V Withdrawal of the sea between the coast of Campania and the Island of Capri (beach near Serino); “fiery” waters in the

coastal zone of Amalfi; territory around Serino; Ottaviano. Loud underground noises, emission of a cloud from the crater;hurling of rocks, lightning, emission of ‘fire’ from the fissure that opened in the Atria

12 16 10 – 12 16 11 1 h V Raining ash in Campania, Puglia, Basilicata, and regions that face the eastern coast of the Adriatic and on the northern coastof the Aegean, as far as the current Strait of the Dardanelles; darkness; sulphurous emissions, dust suspension (Campania region)

12 16 10 – 12 16 12 2 h C Moderate seismic activity; underground noises; cloud; darkness(in Naples)12 16 10 – 12 16 15 c. 6 h V Falling ashes12 16 12 – — — — ? V Rough seas in the Gulf of Naples, between Naples and the coast overlooking the cliff of Rovigliano/mouth of the Sarno

[the stretch of the coast affected by the phenomenon is about 16 km long]12 16 12 – — — — ? C Eruption of volcanic material; hurling of fiery masses from the central crater in the direction of Ottaviano12 16 13 – — — — ? V Warm emissions; strong underground noises; hurling of rocks; intense seismic activity: collapse of the wall of the central crater;

fissure opening in the Atria, central crater and zone lying between the two craters12 16 13 – 12 17 — 2 d C Raining ash, hurling rocks and pomice stones from the fissure opening in the Atria as far as northern Puglia (Apulia Daunia);

Arpaia (CE), eastern slope, in the direction of the city of Nola, Ariano Irpino (AV), Avellino12 16 04 – 12 17 — c. 1 d V M Raining ash; hurling rocks and pumices from the fissure that opened in the Atria, eastern slope, in the direction of Nola,

Ariano Irpino, Avellino12 16 04 – 12 17 — 1 d V Underground noises felt at a great distance12 16 15 – 12 16 — ? V Clouds of smoke; raining ash; sulphurous emissions; hurling rocks

The rain of ash and rocks fell violently upon Nola, Palma Campania, Trocchia - Pollena and Ottaviano. The first of these cities,in particular, was repeatedly hit by rocks hurled from the volcano. The rock fall-out above all affected the north-eastern side.The cities furthest away are Nola and Palma Campania, (at about 12 km from the crater)

12 17 11:30 – 12 1712

30' min M Seismic activity (Vesuvius area); raining ash and rocks from the central crater; particularly upon; eruption of fire fromthe central crater, above all upon Torre del Greco (Herculaneum) and Torre Annunziata (Pompeii), as far as the sea

12 16 16 – 12 16 18 2 h V Intense and continuing seismic activity in the Vesuvius area12 16 17 – 12 16 18 1 h V Increase in the eruptive activity; darkness (northern side of the volcano; Ottaviano, Palma Campania, Lauro, Trocchia-Pollena,

Somma Vesuviana)12 16 17 – 12 16 18 1 h C Intense seismic activity felt at Naples12 16 17 – 12 16 22 5 h M Raining ash; increase in the seismic activity (Vesuvius area; Naples)12 16 19 – 12 16 22 3 h V Fiery vapour? (Torre Annunziata) fire in the woodland area at Herculaneum12 16 19 – 12 17 05 10 h C Raining ash and earth at a great distance5, darkness in the Vesuvius area12 16 20 – 12 17 10 8 h V C Unidentified luminous phenomenon12 16 20 – 12 17 05 9 h C Moderate seismic activity in the area of Vesuvius and Naples12 16 20 – 12 17 05 9 h V Darkness; cloud; lightning; underground noises (Vesuvius area); rough seas along the coast overlooking the Vesuvius area12 17 05–12 17 08 3 h V C Darkness; sulphurous emissions; dust particle suspensions described in Naples); smog, raining ash (Vesuvius area; Naples)

outflow of ashes, darkness; lightning (Vesuvius area)C Withdrawal of the sea and subsequent return wave in the sea facing the Vesuvius area, for c. 370.8 mV Withdrawal of the sea facing Portici, Resina, Pompeii and Herculaneum (ancient site) for about 55.35 m from the coast,

and the return of the water was not wholly completeFacing Castellammare di Stabia, Granatello for about 50–70 m; length c. 550 m. At Torre del Greco, length c. 370 m;width c. 75 m. At Torre Annunziata length c. 180 m, c. 35 m

12 17 05 – 12 17 13 8 h C Loud underground noises, intense and repeated seismic activity12 17 08 – 12 17 09 1 h V M Abundant rainfall (Naples)12 17 09 – 12 17 — ? V C M Obstruction of the waterways and subsequent flooding that affected the following towns and areas: Pollena, Trocchia,

Massa di Somma, the plain of Palma Campania, Lauro and its neighbourhoods, Nola, and the villages, Marigliano and Cicciano,Arienzio and Casalnuovo di Naples; south-eastern side, in particular along the bed of river Sarno, in the direction ofTorre Annunziata; obstruction of the water pipes (pipes from Limatola to Maddaloni and Arienzo; north-western sideand underlying soil, in the direction of Arienzo and Maddaloni)

12 17 09 – 12 17 11 2 h C Underground noises (Vesuvius area)12 17 09 – 12 1711-13

2–4 h C Underground noises, eruption of “fire” from the central fissure of the Atria at Torre del Greco (some homes burned down andthe church of the Carmelitani), direction Massa di Somma and San Giorgio a Cremano; raining ash, hurling of rocks6,strong seismic activity at Torre Annunziata

12 17 09 – 12 17 15 6 h C Eruption of ‘fire’; hurling of rocks; raining ash; obstruction of the waterways and subsequent flooding7; perhaps obstructionof the aqueducts in the south-eastern side, in particular along the bed of the River Sarno, in the direction of Torre Annunziata;north-western side, and underlying soil, in the direction of Arienzo (Argentia) and Maddaloni (Mataluni)

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Table 3 (continued)

Date chronologicalrange

Duration Source Summary of the description

M d h

12 17 09 – 12 17 11 2 h V C M Variations in the coastline, with the uprising of ‘new wharves’ in the sea, created by the material transported by the ‘fiery’ river(Gulf of Naples, from the port of Naples to Castellammare di Stabia; sea facing Granatello, Torre del Greco and Torre Annunziata

12 17 10 – — — — ? V Sudden stillness of the air and the sea at Naples and in the sea aheadUnderground noises accompanied by hurling lapilli and followed by the emission of seven rivers of fire coming from the central crater

12 17 10 – 12 17 12 2 h V 1st river of fiery ash in the direction of Naples, passing along the bed of the Sebeto, the territories of Barra and San Giorgio a Cremano,the surroundings of Villa Nava, as far as flowing into the sea, near the sanctuary of Santa Maria del Soccorso

partiallyCM

2nd river of fiery ash towards Portici and as far as the sea; variation in the coastline. From the central crater, deviating after 0.922 km,with a front of c. 0.553 km3rd river of fiery ash, deviates after 1.107 km, heading towards Ercolano, as far as the sea, with a front of at least c. 1.845 km4th river of fiery ash, from the central crater, deviating after c. 0.11 km, directing towards Torre del Greco, with a front of c. 5.535 km5th river “of fire” across the territory between Torre del Greco and Torre Annunziata, as far as the sea, with a front of c. 1.845 m6th river “of fire” in the direction of Torre Annunziata and Boscoreale as far as the sea7th river “of fire”, ash and “fiery bitumen” in the direction of Ottaviano, Pollena–Trocchia, Santa Anastasia, Massa di Somma and the smallinhabited centres in the surrounding areas; suspension of ash and dust in the air

12 17 10 – — — — ? V Underground noises, accompanied by hurling lapilli and followed by the emission of seven “rivers of fire” (from the crater)12 17 10 – 12 31 — 15 d V Repeated seismic activity12 17 09 – 12 17 11 2 h C Raining ash; hurling rocks12 17 09 – 12 17 11 2 h C Strong seismic activity (Torre Annunziata) raining ash as fare as the port of Vaissetun?12 17 10 – 12 17 13 3 h V Sudden drying up of the waters in a basin in the territory of Ottaviano12 17 10 – 12 28 — 11 d V “Fire” in the sea facing Portici12 17 10 – 01 14 — 28 d V Repeated seismic activity in Naples12 17 13 – 12 17 15 2 h C Cloud, seen from Naples12 17 17 – 12 17 21 4 h V Fiery glows, seen from Naples12 17 — – 12 18 — 1 d V Obstruction of the waterways and subsequent flooding of the territory of Arienzo, Nola, Arpaio and Cicciano12 17 20 – 12 18 05 9 h C M Seismic activity felt in the Vesuvius area felt and Naples; fiery emissions; rocks hurled from the central crater12 7 20 – 12 18 05 9 h M “Boiling over” of the waters of the sea in the coastal zone of the Vesuvius12 18 05 – 12 18 07 2 h V Diminution in the eruptive activity12 18 06 – 12 18 08 2 h C Cloud from the central crater12 18 06 – 12 18 13 7 h C End of the fiery emissions coming from fissure opening in the Atria; emissions from the central crater12 18 17 – 12 19 17 1 d M Cloud, seismic activity, underground noises in the Vesuvius area and Naples

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interpreted. Table 1, for instance, shows the complexity of theselinguistic transfers and the variety and overlap of terms that wereused to indicate words that today have a precise and unequivocalmeaning.

6. The heart of the results: a chronology of the great eruption withindividual memories compared

On the grounds of the synoptic comparison of the three treatises,a chronology of “cold” data was prepared, in the previously definedsense. Tables 2, 3 and 4 provide the heart of the results. Thisoperation has required the formation of a small database, which hasallowed us to select the various phenomena described and arrangethem according to various indicators, among which there is theiroccurrence in time. The time indications are provided by thetreatises as canonical hours (i.e. from daybreak to sunset) or ashours all'italiana (i.e. from sunset to sunset): together, these localuses were transformed into the single time system of today(universal time). The hours are obviously approximate owing to alack of recording of less than a half hour.

In the three treatises, the phenomena that occurred are narrated ina way that is in accordance with the purposes of the narrator, andbecause of this, the phenomena observed are often not described inchronological order. The three authors, and in particular Varone(1634), often introduce fragments of personal memories to explain orcontextualise some of the events, or to reinforce their theoretical linkswith ancient tradition: for this reason the narrative is discontinuousand is performed at different levels.

The measures adopted by the authors to quantify various aspectsof the reality that they describe also require some clarification. Theproblem is not so much the conversion of the ancient measures (intopertiche, passi, tumoli, miglia napoletane ecc) into the current metricones, but rather to understand if these measures can be trusted. Theimpression one has is that some of the measures used are

exaggerated, not only because they were influenced by the emotionssurrounding the event, but also mainly because the forma mentis ofprecision was not widespread at the time. For example, the height ofthe pine-tree shaped cloud that rose into the sky from Vesuvius on16 December, 1631, was indicated by Varone as equivalent to circa37 km (but is instead considered to be circa 15 km by Rosi et al.(1993). Instead, the distances between the various locations, thepaths of the “rivers” and the “rivers of fire”, and the burnt surfacesalmost always appear to be congruent. For the analysis of these“rivers” of materials erupting from Vesuvius that are described inthe three treatises, it is necessary to note that this section is a rathercomplex one that has not yet been adequately analysed. Forexample, Varone listed seven “rivers”, while Carafa and Mascolowere less precise. A more direct comparison between the threeauthors will indeed be interesting to have a precise picture of theerupted materials at last and to provide a critical understanding ofthe relationships between these texts and the use that has beenmade of them by volcanologists in the literature. In this regard,Varone, who appears to be wholly independent from the other twoauthors, provides highly detailed chronological and topographicalparticulars, along with a description of the materials which the“rivers” consisted of. The descent of the seven rivers, which issummarised in Table 3, is an important part of the treatises; thetreatise of Varone contains many details.

From Varone, we can appreciate that therewere seven “rivers” thatwere different in their directions and in the materials of which theywere composed (at least as they were perceived through the eyes of awitness of the time). The first river was described as being of “fieryash”, and as heading in the direction of Naples (see Table 3 for theroutes); also the second river was of fiery ash and in heading towardsPortici it reached the sea, causing a variation in the coastline; this riverarose from themain crater and it deviated after 0.922 km; its front wasof circa 0.553 km. The third river, which was also of fiery ash, deviatedafter 1.107 km, heading towards Ercolano, as far as the sea, with a front

Table 4Vesuvius activity: from midday on 18th December 1631 to 31st December 1632 see legend in the Table 2

Date/Chronological range Duration Source Summary of the description

1631, 12 18 — – 12 20 –– 2 d V Collapse of part of the wall of the crater of Vesuvius; underground noises; seismic activity (also felt in Naples)12 18 — – 12 24 –– 6 d V Rocks hurled from the crater, onto the slopes; smoke emissions; warm emissions; thunderclaps (from the crater, Vesuvius area)12 18 — – 12 25 — 7 d V Moderate and continuing seismic activity (in Naples)12 18 — – 12 31 — 13 d V Moderate and repeated seismic activity, with at least 60 shocks (in Naples) rocks hurled (from the crater, on the slopes)

underground noises (Vesuvius area, Naples)12 18 — – 12 31 — 13 d C M Moderate and repeated seismic activity, with at least 60 shocks (in Naples)12 18 17 – 12 19 17 1 d M Cloud12 19 05 – 12 20 07 1 d M Storm (Vesuvius area; Naples)12 19 17 – 12 20 17 1 d V Underground noises; rocks hurled; fiery emissions from the central crater12 19 17 – 12 21 17 2 d C Fiery emissions; seismic activity, cloud (from the crater; visible in Naples)

M seismic activity (Vesuvius area; Naples)12 20 17 – 12 21 17 1 d M Violent storm (Vesuvius area — Naples)12 21 17 – 12 22 17 1 d V Underground noises; seismic activity (in Naples);

M Darkness, suspension of ash and dust (Vesuvius area; in particular in Nola)12 22 17 – 12 24 17 2 d V Underground noises; seismic activities (in Naples)12 23 17 – 12 24 17 1 d M Flooding (Nola and outlying territories)12 24 11 – — — — ? M Darkness(Vesuvius area)12 24 17 – 12 25 17 1 d M Rain of ash (Vesuvius area)12 24 — – 12 31 — 7 d V Smoke emission (Vesuvius area)12 25 17 – 12 26 17 1 d V Falling of fiery rocks? (the Church of Santa Maria di Pugliano was hit)12 29 05 – 12 29 08 3 h M Storm; underground noises; hurling of fiery rocks; ash from the main crater, in the direction of Marano and the sea12 30 05 – 12 30 08 3 h M Intense seismic activity (Naples)12 30 22 – 12 31 07 9 h M Storms; eruption of water and fire (Vesuvius area, above all in the vicinity of Herculaneum and Ottaviano)12 31 — – 06 18 — c. 5 m V Moderate and repeated seismic activity, with at least 60 shocks (in Naples) rocks hurled (from the crater,

on the slopes) underground noises (Vesuvius area, Naples)12 31 — – 06 18 — c. 5 m C M Moderate and repeated seismic activity, with at least 60 shocks (in Naples)12 31 — – 06 24 — c. 6 m V Smoke emission (Vesuvius area)12 31 17 – 01 01 17 1 d V Underground noises; seismic activity (in Naples)12 31 17 – 01 01 07 14 h M Sulphurous emissions in Naples1632 01 01 — – 01 14 — 14 d V Repeated seismic activity01 01 20 – 01 02 17 21 h M Seismic activity, sulphurous emissions (Vesuvius area, Naples)01 01 17 – 01 02 17 1 d C M Raining ash (Naples)01 02 — – 03 12 — 2 m C Emissions of smoke (from the central crater), smoke emissions (sea facing Torre Annunziata)01 05 17 – 01 06 17 1 d V Underground noises; seismic activity (in Naples)

M Sulphurous and bituminous emissions (?) (Vesuvius area; Naples)01 06 22 – 01 07 07 9 h M Seismic activity (Vesuvius area; Naples)01 06 — – 02 23 00 1 m 18 d M Fiery emissions; seismic activity (Vesuvius area; Naples)01 07 07 – — — — ? M Falling of fiery rocks (the Ospizio della Quercia was hit)01 09 05 – 01 09 12 7 h M Fiery emissions; dense smoke emissions; darkness (Vesuvius area; Naples)01 15 17 – 01 16 17 1 d V Seismic activity (in Naples)01 30 17 – 01 31 17 1 d V Smoke emissions; fiery emissions (from the central crater; in Naples)02 04 17 – 02 05 17 1 d V Smoke emissions; fiery emissions (from the central crater; in Naples)

M Seismic activity; fiery and bituminous emissions (Vesuvius area; flooding due to the heavy precipitations (Mount Abella)02 12 17 – 02 13 17 1 d M Two strong shocks felt in the Vesuvius area and in Naples; eruption of incandescent ash from the crater02 16 — – — — — ? C Emissions of smoke and darkness, underground noises, sulphurous emissions (central crater)02 16 — – 03 12 — 24 d C Progressive enlargement of the mouth of the crater, smoke emissions, sulphurous emissions, fiery emissions (central crater);

fissure opening in the Atria; moderate and continuing seismic activity (in Naples) underground noises, darkness (Vesuvius area)02 18 17 – 02 19 17 1 d M Underground noises; sulphurous and bituminous emissions (?); seismic activity (Vesuvius area)02 19 17 – 02 20 17 1 d V Underground noises; moderate seismic activity; sulphurous emissions; darkness(in Nola)02 20 17 – 03 01 17 9 d M Fiery emissions (Vesuvius area)02 23 17 – — — — ? M Raining ash (Vesuvius area, Naples)03 01 — – 03 12 — 11 d C Fiery emissions from the central crater03 02 17 – 03 03 17 1 d M Heavy rain; rocks from the volcano's crater; sulphurous emissions (Vesuvius area)03 11 17 – 03 12 17 1 d V C Underground noises; smoke emissions (from the central crater; in Naples)03 13 22 – 03 14 07 9 h M Seismic activity; hurling of incandescent rocks (from the crater; Vesuvius area)03 21 17 – 03 22 17 1 d M Seismic activity (two shocks); fiery and sulphurous emissions (Vesuvius area)04 01 — – 04 20 — 19 d M Emissions of smoke from the sea; “boiling over” of the waters (coast of the Gulf of Naples, roughly from

Naples to Castellammare di Stabia)04 18 17 – 04 19 17 1 d M Raining ash; underground noises (from the crater, as far as Naples)05 19 17- 05 20 17 1 d C Underground noises (Vesuvius area)water eruption (slopes of the Vesuvius)05 31 22 – 06 01 05 1 d M Seismic activity (Vesuvius area)06 — — – 11 — — c. 5 m M Seismic activity; sulphurous emissions (Vesuvius area; Naples)06 22 04 – 06 22 05 1 h C M Strong seismic activity; underground noises (Naples) — smoke emissions (from Naples)06 22 15 – 06 22 17 2 h M Moderate seismic activity (Naples)06 22 17 – 06 22 22 5 h C Smoke emissions07 09 05 – 07 09 08 3 h M Moderate seismic activity (Naples)07 31 03 – 07 31 06 3 h M Seismic activity (Naples)08 13 22 – 08 14 05 7 h M Seismic activity (Naples)08 13 17 – 08 14 17 1 d M Intense atmospheric precipitations (Campania region)09 — — – 11 — — c. 2 m M Intense atmospheric precipitations (Vesuvius area)09 01 –– – 09 30 — 29 d M Repeated seismic activity of moderate intensity (Naples)09 16 17 – 19 17 17 1 d M Seismic activity (Naples)09 25 18 – 09 25 20 2 h M Seismic activity (Naples)09 27 17 – 09 28 17 1 d M Sulphurous emissions (from the crater; in Naples)10 26 05 – 10 27 20 c. 2 d M Dense smoke emissions (from the crater)

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Table 4 (continued)

Date/Chronological range Duration Source Summary of the description

1631, 12 18 — – 12 20 –– 2 d V Collapse of part of the wall of the crater of Vesuvius; underground noises; seismic activity (also felt in Naples)11 09 06 – 11 09 08 3 h M Moderate seismic activity (Naples)11 28 17 – 11 29 17 1 d M Darkness11 19 05 – 11 19 07 2 h M Seismic activity; dense smoke emissions (from the crater; in Naples)12 02 05 – 12 02 08 3 h M Moderate seismic activity (Naples and neighbouring territories)12 08 05 - 12 08 08 3 h M Seismic activity (Naples)12 08 22 – 12 09 07 9 h M Seismic activity (Naples)12 15 22 – 12 16 17 19 h M Heavy atmospheric precipitations; underground noises (?); seismic activity; sulphurous emissions (Vesuvius area, Naples)12 18 — – 12 20 — 2 d V Collapse of part of the crater wall, underground noises, seismic activity

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of at least circa 1.845 km. The fourth river was also described as beingof fiery ash that arose from the central crater, and it deviated aftercirca 0.11 km, heading towards Torre del Greco, with a front of circa5.535 km. The fifth and sixth rivers were instead described only asbeing “of fire”; the fifth crossed the territory between Torre del Grecoand Torre Annunziata, as far as the sea, with a front of circa 1.845 km,and the sixth river headed in the direction of Torre Annunziata andBoscoreale, as far as the sea. Finally, the seventh river was formed ofash and “fiery bitumen”, and it descended in the direction of Ottavianoand Massa di Somma.

Fig. 2 shows an image, which was not a part of the treatises, butinstead drawn by a contemporary, of some of the seven “rivers” thatpoured from the central crater, some of which reached the sea. Despite itslimitations, the chronological reconstructionof theeventshas thepurposeof providing the order, of correlating and integrating the observations ofthe various authors, as we follow the unfolding of the events.

The earthquakes mentioned have been selected, recomposing thepicture of the perceived seismicity, which is obviously less than thereal one (which today can be obtained from instrumental detectors),which will have been well below the sensitivity of human perception.In Fig. 3 the landslips and landslides on Vesuvius are indicated; thesemight have been deformations that preceded the eruption, and the

Fig. 2. Some of the seven “rivers of fire” described in the treatises examined here, seen as

various shocks before and after the eruption, from October 1631 toJanuary 1632, according our three authors.

Fig. 4 represents the felt seismicity fromFebruary 1632 to September1633, as described in the three treatises. For this aspect, it can be seenthat most of the eventsmentioned are of an intensity between III and IVdegrees on the MCS; then there are periods of slight and incessantactivity, which remain as anoverall indication. There are also two eventsof more sustained intensity (VII MCS), that occurred soon after theeruption, on 17 December and 18 December, 1631, in Torre Annunziata(described by Carafa). The overall trend of the seismicity justifies thestate of alarm, panic and prostration that the population of the Vesuviusarea underwent in the space of at least 3months, evenof only becauseofthe continuing seismic activity: an element that today is not secondarywith a view to information and prevention.

From summer 1631 to 16 December, 1631, at 4.00–5.00 h UT (i.e.until the beginning of the explosive phase of the eruption), a“countdown” was also calculated, to give an immediate idea of thetype of phenomena that we can today term as “precursors”.

Some ideas as to how the contemporary people saw andexperienced this eruption is also contained in the iconography ofthe times, which set the memory of particular aspects of that event.The availability of images of this eruption, as is known, is very

a print by J. Passari (Bibliotèque Nationale de France, Estampes et Photographies, VX46).

Fig. 3. The Vesuvius area. Some of the phenomena reported in the examined treatises are indicated here, which occurred from September 1631 to January 1632: probabledeformations, which are not specifically detailed in the treatises, but are described as some visible effects, such as small landslides or landslips, on Vesuvius. Variations in the waterchemistry, noise and seismicity are also indicated.

356 E. Guidoboni / Journal of Volcanology and Geothermal Research 178 (2008) 347–358

extensive. Here I have chosen some of the lesser known images thatgive a particular idea of the phenomenon and that in a certain sensealso explain the chronological data (see Table 2).

As regard to the social aspects and the anthropomorphic impact, thesources of the time are very many and very rich. To limit ourselves hereto an immediate and synthetic suggestion, we can see Figs. 5 and 6: theformer shows an image of the disaster as seen by thewitnesseswho sawthe eruption from Naples: a dense and very dark cloud enveloped theVesuvius area and the city itself, and Vesuvius was almost concealedbehind an enormousmass of smoke and ash. In the latter Fig. (Fig. 6) thevolcano is almost of secondary concern, with emphasis on the socialunrest and the population movement that the event triggered: it was atrue and proper exodus from the country villages towards Naples, anevent of social unrest that the author placed in the foreground as

Fig. 4. The Vesuvius area. Perceptions and mentions of earthquakes are shown

compared with the natural phenomenon. This image immediatelyconveys the implications of an eruptive eventwhich, if it occurred today,would have far more devastating impacts in the current demographicand economic scale of the area (over 700,000 people).

7. Discussion and conclusions

The analysis performed on the treatises of G.B. Mascolo, G. Carafaand S. Varone can be considered as the initial phases of a study andanalysis that should include other Latin treatises and the ones writtenin Italian and Spanish, as well as other types of sources (administrativeand fiscal). This first analysis has made available a volcanologicalinterpretation of a broad chronology and description of the phenom-ena that preceeded, accompanied and followed the 1631 violent

from the three treatises examined, from February 1632 to September 1633.

Fig. 5. The great cloud and black smoke that enshrouded Vesuvius during the eruption on 16 December, 1631, as seen in a particular from a painting of Rocco Spataro, an eye-witnessof this event (Naples, private collection).

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eruption phase. Among the precursor phenomena, some new oneshave also emerged that were previously unknown in the literature,and that are better analysed and interpreted in Bertagnini et al. (2006)on the base of the three treatises (Guidoboni, 2004).

The analysis of the Latin terms used to describe the phenomen-ology of the eruption in the three treatises has paved the way to aseries of considerations that can be summarised:

i) there is no direct relationship between the terms in thetreatises and the current volcanological lexis;

ii) it has been possible to build a chronology of cold data from thetreatises (as it would have been for other contemporary texts),with a significance not of objective data – as would maybe beequivalent to instrumental data – but of data interpreted onlyfrom a historical and philological point of view;

iii) the interpretative phase of the volcanologists should followfrom the cold data and be performed in a transparent manner.

The method of analysis applied in this study has shown, in myopinion, that it is possible to avoid apparent conflicts in data in thephase of scientific interpretation. This aspect is strongly multi-disciplinary: bearing this inmind avoids the risk of “circular thinking”,which can easily take shape between opinions (or hypotheses, or data)of the volcanologists and historical testimonies (see the problem ofthe presence or absence of lavas discussed above).

An exact picture of the occurrence of the great 1631 eruption ofVesuvius presents some elements that are also relevant with a view tocivil protection, such as the type of precursor phenomena perceivedby the witnesses and the time that elapsed before the acute phase ofthe eruption. With a view to prevention, other interesting aspectsinclude the extent of the area where the ashes fell, the overall humanimpact, the number of dead (which fluctuates between 300 and 1000;far fewer than the figure reported in the literature), and the intensemigratory flow towards the city of Naples that was triggered by the

eruption. To evaluate the last of these, we have made use of thehistorical demographic data available in the literature. As a whole, theanalysis performed has allowed us to locate 126 villages or isolatedbuildings that underwent effects of various kinds due to this eruption(e.g. ashes, fiery masses, water, mud) and the detailed picture shouldin any case be eventually better studied.

For the social aspects and the economic impact in the villages of theVesuvius area, there are, of course, many other types of sources ofinformation that are more specific than these treatises, such as theadministrative and fiscal records, the correspondence between thecentral power and the local administrations, and the feudal administra-tions (preserved in the State Archives and by the present-day Councils).

Furthermore, the topography of Vesuvius and its changes followingthis eruption can now undergo further assessment through scanningthe database for such manifestations and subjecting them tovalidation in the field.

Acknowledgements

The textual analysis and critique of the treatises was carried outwitha working group comprising a researcher from SGA — Storia GeofisicaAmbiente, funded by the Exploris project in 2002–2003. We would liketo thank the following for their participation in this study and analysis:Federico Sant'Angelo and Federica Foschi for the translations from Latin;Gaia Fanelli andMaria Giovanna Bianchi for the selection of the texts forthedatabase;DanteMariotti for the localisation and the geo-referencingof the cited toponyms and the volcanic effects.

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Fig. 6. The eruption of Vesuvius in 1631: the social unrest and the populationmovements that the event triggered off. Painting by Scipione Compagno (Vienna,Kunsthistorisches Museum).

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