The volcano of Jorullo (1759) and the official record made of its birth
A volcano broke out of flat sugar-cane country in Michoacan on 29 September 1759. Within a fortnight the alcalde mayor had reported it to the viceroy and required the administrator of the ruined estate to keep a daily narrative; the viceroy asked whether lava had run, and a pound of the affected sand was collected and sent up. The eruption also destroyed a hacienda and emptied a pueblo de indios. Both halves are in the same file.
Why this wins its question: English-language accounts of Jorullo begin with Humboldt, who arrived forty-four years late, and treat the eruption either as a geological curiosity or as the occasion of his mistaken theory of elevation craters. What they leave out is the file: that within a fortnight a district magistrate had reported to the viceroy, that the authorities were ordered to send in what they knew, that a named estate administrator was commissioned to keep a daily narrative and did so for six weeks, that the viceroy asked specifically whether lava had flowed, and that a pound of sand was collected and forwarded with a proposed method of separating it and an explicit admission that the collector did not know what it was. This entry quotes that record from the transcription of the expediente, and it puts on the same page the 150,000 pesos, the starving cattle, the hungry labourers, the emptied pueblo de indios that had to carry its own church to Churumuco, and the chaplain who tried to exorcise the volcano - none of which a defence of colonial science would include, and all of which is in the sources it rests on.
Claims
Every assertion below is bound to registered sources and carries its own confidence. Weight them; do not treat the page as uniformly authoritative.
The eruption had three months of warning and the warning was written down. The diary forwarded to the viceroy records that on the hacienda of Jorullo and its surroundings there began to be heard and felt, "en fines de Junio del presente ano de 59, unos retumbos o golpes, debajo de la tierra, repetidos pero sin temblar", so extraordinary in sound and seeming to come from directly beneath the hacienda that they frightened everyone living there; the noises grew in number and were joined by earth tremors which "aunque no principiaron muy fuertes, lo llegaron a ser luego que entro Septiembre", by which time the large body of workers on the estate was terrified and beginning to abandon it and go up to live in the neighbouring hills. On 17 September at nine in the morning a roar was heard "pareciendo que tiraban una andana de canones en el centro de la tierra"; the chapel cracked and the tiles were shaken from its roof.
The document records something its writer could not explain and did not suppress. He notes that the workers' flight came less from the noises and tremors than from a rumour circulating among them: "una voz vaga que entre ella misma se esparcio, afirmando que el dia de San Miguel se habia de acabar Jorullo, sin que de este aguero les hubiese podido desvelar persona alguna ni menos investigar el origen de semejante voz." The day of San Miguel is 29 September, and that is the day the volcano broke out. The administrator states the coincidence, says he could neither talk the people out of the omen nor trace where it came from, and leaves it there; nothing read here explains it, and this entry does not either.
The outbreak is dated and placed to the quarter-hour and the quarter-league. It came "el 29 del dicho Septiembre, dia de S. Miguel, y a las tres de la manana, a distancia de un cuarto de legua de las casas de la hacienda, por la parte que declina del Oriente al Sur, en una canada que se llama Cuitinga", where after "tres o cuatro muy recios temblores" a very dense black column of smoke burst out, then a tempestuous and horrible noise, and then flames "que en globos brotaba con gran violencia para lo alto". Frightened, the administrator and the people went to hear mass in the chapel, and while they were at communion it began to rain water mixed with earth, so that when they came out the ground was covered with mud and the roofs loaded with it, the sky strangely darkened and the explosions so thick and thunderous "que causaba fuerte pavor y espanto, con mucho hedor a azufre".
The contribution claimed here is administrative, and it is documented in the file itself. On 13 October 1759, a fortnight after the outbreak, the alcalde mayor of Michoacan, teniente coronel D. Martin de Reinoso Mendoza y Luyando, reported the event to the viceroy, the marques de las Amarillas, "acompanando el siguiente diario de observaciones". Orders were issued to the local authorities "para que suministren cuantas noticias sepan acerca del volcan". The administrator general of the affected haciendas, D. Manuel Roman Sayago, records in his own heading that the alcalde mayor had required of him a "veridica, diaria y puntual narrativa de los efectos del consabido volcan del Jorullo", together with a report on the state of the pueblo de la Guacana, expressly so that the viceroy should be informed of it. A daily observational record was thus commissioned by name, from a named officer, in the first fortnight of an eruption, and it survives.
The enquiry went further than narrative: it asked a specific physical question and it collected a specimen. On 13 November the administrator went down to the volcano again "a fin de reconocer si ha corrido el betun o lava que manda S. E. se le noticie en particular" - the viceroy had asked to be told about that in particular. He describes the old waters of the hacienda running thin and clear over the sanded flats, with a white sediment on the bed "a modo de cal desleida, tirante a amarillo, y delgado como un pliego de papel de estrasa", showing a pearly greasy sheen at the edges which broke up and dissolved when he tried to roll it on his finger; being unable to collect the substance itself, he took instead "las arenillas que me parecieron estar mas infectas de el" and remitted about a pound of them to the alcalde mayor, suggesting that water poured on the sand and allowed to settle would separate it out. He then states the limit of his own competence in as many words: "ni yo tengo conocimientos de dicha lava, ni ha habido persona que me diga que materia sea; pero sea la especie que fuere, no corre otra cosa que la que llevo dicho."
The observer also reasoned, and his four closing clauses are the nearest thing in the file to analysis. The first is comparative and is the sharpest: that the eruption came "no haber rompido en lo alto de algun cerro, como se ha verificado en los demas volcanes que se ven en este reino, sino en lo mas hondo y plano de la canada de Cuitinga". The second records what would now be called volcanic lightning - that when the cloud thickened it formed storms in the sky "arrojando repetidos rayos, centellas, exhalaciones y otros tiros de fuego". The third measures the new edifice: so many red-hot stones have been thrown that around the vent they have built "un brocal, pretil o circulo que ya pasa su altura de trescientas varas", overtopping the sides of the ravine it has filled and disfigured. The fourth is that in all the destruction "no han peligrado por Divina Providencia persona ninguna", only the workers and inhabitants scattered and wandering, many of them unaccounted for. The relacion is signed and dated "en esta labor de Cuarallo, en trece dias del mes de noviembre de mil setecientos cincuenta y nueve anos.—Manuel Roman Sayago."
The cost to property and to the people who worked it is in the same sentences as the observations, and it is not small. The hacienda - a rich sugar, stock and grain estate belonging to D. Jose Andres de Pimentel, regidor of Patzcuaro - was ruined on 29 September, its loss put "segun el administrador y muchos inteligentes a 150.000 pesos"; the writer says the greater pity was "las hambres y desnudeces que ha padecido la pobre gente operaria que la servia", who lost nearly everything, and the sight of the oxen, mules and horses wandering the hills without a branch to eat, some of them dying isolated and unreachable. Dry ash later covered the pastures of the cattle hacienda of San Pedro four leagues off and reached Oropeo, Guadalupe, Zicuiran, Cungaripo and other stock estancias ten and twelve leagues to the west, leaving the beasts with nothing to graze and no water to drink, since the streams ran "infecta de materias sulfureas". The copper mines of Inguaran, five leagues to the south, were nearly emptied of their workforce - and the file adds, without comment, that the operarios were afterwards "restituyendo ... a solicitud de los mandones".
A pueblo de indios was destroyed and its community moved itself out. La Guacana, the head town of the parish about half a league from the hacienda de la Presentacion, was depopulated on 5 and 6 October; its curate "salio huyendo a pie tras de todo el pueblo que iba puesto en fuga", sheltering on the cerro de Cuarallo and at the puerto de Tamacuaro, where they took the images of their church. Later in the month the curate and the Indians of the pueblo came down to take out the sacred vessels, ornaments, side altars and the goods of the clergy, and moved to Churumuco some fifteen leagues south in the same parish, "por no haber quedado el mas leve fundamento de poder habitar en el citado pueblo de la Guacana"; they carried away all their property, movables and cattle, "asi de cofradias como de comunidad", and the town was left waste with the roof of its church fallen in. The writer records that the removal was made at immense labour "por el incesante llover de arena seca y opacidad de aquel pais, padeciendo de los ojos y sin poder hacer de comer". He does not say whether all the Indians of the pueblo reassembled at Churumuco, and says he cannot: "No sabre decir si todos los indios se han congregado a Churumuco."
The response was liturgical as well as documentary, and the same file records both without embarrassment. Before the outbreak the administrator sent to the Jesuit colegio of Patzcuaro for padre Isidoro Molina to come and say rogation masses and lead acts of penitence "para aplacar la ira divina"; Molina arrived on 20 September and began a novena of masses and a mission of confessions the next day. On 15 October, when the cloud shifted, the image of Nuestra Senora de Guadalupe was carried out of the cracked chapel unharmed and taken on foot and on shoulders to the cerro de Cuarallo in procession by more than a hundred and fifty of the labourers, men and women, singing the salve. On 7 November the chaplain of the neighbouring hacienda of Nombre de Dios, Br. D. Jose de Arriaga, came to exorcise the volcano; a fresh roar from the vent drove the party off in flight, and he withdrew half a league further and exorcised it "desde un alto con el conjuro de tempestades". The same administrator who collected the sand specimen recorded the exorcism, and this entry does not tidy either out of the account.
What the place looked like afterwards, and what it gained, is set down by the Mexican compiler of 1854. The volcano appeared "en lo mas bajo de la canada de Cuitinga", whose materials filled the ravine and then piled around the vent to a considerable height; the ground blistered "formando vejigas hasta de 180 metros de elevacion"; sands covered the pastures and burned the trees; the ashes fell "hasta cincuenta y siete leguas en linea recta del crater". The cone stands "1.578 pies sobre los planes que lo rodean", and around it, on ground called el Mal pais, are "millaradas de pequenos conos de dos a tres metros de altura, muchos de los cuales exhalan un vapor espeso y se conocen con el nombre de hornitos". There had been no further eruption. The streams of Cuitinga and San Pedro, swallowed at first in the fissures, reappeared as hot springs, and "en 1803 su temperatura era de 65" degrees. And the balance is struck in one sentence that gives both sides: "el pais es triste y esta desolado, las cenizas llevadas a lo lejos abonaron la tierra y contribuyeron a dar fertilidad a una gran estension de territorio."
The famous European account of Jorullo rests on the witnesses this file was made of, and the point is worth making carefully rather than triumphantly. The 1854 article observes that the appearance of the volcano "es uno de los fenomenos mas sorprendentes de los verificados en nuestro pais; recuerda el Monte-Novo de Napoles, y llama la atencion de los sabios del mundo", and introduces a quotation from the baron de Humboldt's Ensayo politico which itself begins by citing local testimony: "Los que fueron testigos de esta gran catastrofe, desde las colinas de Agua-Zarca, aseguran que se vieron salir llamas en un espacio de mas de media legua cuadrada." Humboldt was in New Spain in 1803 and 1804, forty-four years after the event, and what he could gather was what the people of the district and the colonial paper trail had preserved. The confidence here is held down because Humboldt's own book was not opened for this object: the quotation is read as the 1854 article prints it, and no claim is made about what else he wrote.
The limits of this entry's evidence should be stated plainly, because two of them are large. First, the expediente itself was not opened: the article that transcribes it says it runs to 46 fojas in the archivo general, and its editor states that he copied only "todo lo que tenga importancia" and that he omits a letter of the cura de la Guacana as adding nothing to the diaries - so the fullest single account of the effect on the Indian town is precisely what the printed text leaves out, and this entry cannot supply it. Second, the drawing the administrator promised and sent does exist, but the 1854 editor who saw it calls it "pintado de negro y rojo, con poco tino y sirviendo apenas para formar idea aproximada del objeto", so the earliest image of the volcano is described here at second hand and not reproduced. Third, no modern volcanological literature was consulted for this object and none of its dates or measurements has been checked against one. Fourth, and deliberately: this entry does not claim that Jorullo was the first birth of a volcano recorded by contemporary observers anywhere, because nothing read here supports a claim of that kind - the 1854 article's own comparison is to Monte Nuovo at Naples, which erupted in 1538.