A Fourteenth-Century Plague Treatise, Part 2



As we saw in the first chapter of this medieval plague treatise, some historical commentators believed the plague was spread via poisonous air. At first blush this seems a precursor to modern germ theory. But keep in mind that classical and medieval authors were ignorant of bacteria and viruses (though they sometimes spoke of airborne “seeds” or semina that spread disease). Nevertheless, they were aware that lingering among the ill could mean getting sick.1 The text in Part 1 warned against eating hot foods or taking baths whenever the plague comes around, since these pleasant activities open the pores to venomous airs. Other treatises warn against exposing the body to southern winds, lest these warm airs dilate the pores and penetrate the heart.2

In this second chapter, the language of organs and their “cleansing places” (clensyng place in Middle English or locus purgativus in the Latin) comes from the classical/medieval theory of the four bodily humors: yellow bile, black bile, phlegm, and blood. The idea was that these fluids are balanced in a healthy person but could become “superfluous” or overabundant, causing sickness. At that point the superfluous humors would need to be purged from the body in order to restore health (and you might be paying a visit to your local leech).3

Modern historians have largely discredited the theory that the medieval plague or Black Death was an outbreak of the Bubonic plague, spread by fleas (though you’ll find plenty of hangers-on, including Wikipedia).4 That said, the Black Death and Bubonic plague share the same major symptom, namely large swellings or buboes on the body. The historian Robert Lerner distinguishes between the kinds of swellings described in medieval sources and those reported in nineteenth-century accounts of Bubonic plague victims:

Although [medieval] chroniclers often mention large tumors in the groin [which is characteristic of the Bubonic plague], they rarely locate them only there. Much more often they have them appearing in two places, groin and armpits, and sometimes in three places, groin, armpits, and behind the ears, or on the throat or neck. Given that the groin, armpits, and neck are the major locations of human lymph nodes, it is reasonable to believe that the Black Death was a lymphatic disease. (210)5

As you’ll see in the translation and transcription below, these lymphatic regions correlate with the organ “cleansing places” that supposedly collected superfluous humors/fluids in medieval medical theory. They were basically describing the lymph system without knowing precisely what that was.

Once more I should note that the Middle English transcription below is my own work, based on an online facsimile hosted by Harvard. All errors are my own. I post this because it’s interesting; it’s not my aim to resurrect humoral theories of medicine (fascinating though they may be).


Chapter 2. The second chapter tells where this sickness comes from and what causes it. Humans have 3 principal parts and members: the heart, the liver, and the brain. Each of these has a cleansing place where it purges superfluities and [thus] cleanses itself.6 The heart’s cleansing place is located under the arms. The cleansing place of the liver is between the thighs and the body and these holes.7 But the cleansing place of the brain is below the ears or under the throat.

This evil comes when the pores have been opened due to one of the causes mentioned above [in the first chapter]. The infected [literally “venemous”] air enters and soon mixes with a person’s blood, thus running to the heart (that is the very ground and root of life and the human nature8) in order to destroy it and kill the person. The heart naturally flees from whatever is opposed or contrary to it and therefore sends the poison to its cleansing place, where, because it is stopped and cannot escape,9 it passes to the next principal part — the liver — to destroy it. In the same manner, the liver sends the poison to its cleansing place, where it is then stopped. Because it cannot proceed once more, the poison passes to the third principal part, which is the brain, which puts it in its cleansing place so that it may not advance from there. And thus the poison is moving for a long time before it rests in any place, [for a space of] over 12 hours. Finally, if it is not released via bloodletting within 24 hours, it festers somewhere and sends a man into sickness and produces a swelling in or near one of the 3 cleansing places.

Middle English Text Transcription

[f. 44v]Chapter 2. The secunde chapitre tellith hou this sekenesse coomyth & what is þe cause thereof. In man [are] iij principall p[ar]ties & members: the harte, the lyver, & the brayne & each hath his clensyng place where he may put oute his sup[er]fluytees & clense hym. The harte hath his clensyng place [f. 45r] vndir the armes. The clensyng place of the lyver is betwene the thies & the body & these hooles. But the clensynge place of the brayne is vndir the eares or vndir the throte.

þan this evill coomyth þus whan the poris ben opyn for sum cause aforeseide, the air venemous entryth and anon mengith with a mannys blode and so renneth to þe harte that is grounde & roote of lyf & mannys kynde for to distroy it and sle the man. The harte kyndely fleeth that is ageyne it & contrar[i] to it & puttith the venyme to his clensyng place and by cause that þat place is stoppid þat it may not oute it passith to þe [f. 45v] next principall parties that is the lyver for to destroy it and it on the same wise puttith it to his clensyng place and for that is stoppid. Also that it may not oute it passith to the thrid principall party that is the brayne and he puttith it to his clensyngplace and yit it may not oute there and thus a long tyme it is moevyng or that it rest in any place xij houres & more. And then at last within xxiiij hours yif it be not passand onto with bloodyng it fastenyth [Thornton: festres] in summe place & castith a man in an ague & maketh a bocche in sum[?] of the iij clensyngplaces or nygh them.

  1. For instance, in the 15th century Giovanni of Capestrano compared the spread of epidemics in the air to the growth of yeasts (Latin fermentum): “It is a rule of doctors that whenever the air in any place begins to be pestilential with the appearance of worms and poxes and measles, which typically precede pestilence, or with the appearance of any pestilential disease […] everyone must move to an air in which nothing of the afore-mentioned appears or appeared in the near past within, at least, six months because of the vestiges of past epidemics, which like yeast [qui velnut fermentum] infect those who move to that place.” See Ottó Gecser, “Giovanni of Capestrano on the Plague and the Doctors.” Franciscan Studies 75 (2017): 27-48 (p. 41). Gecser’s translation.

  2. See, for instance, Joseph P. Pickett’s “A Translation of the ‘Canutus’ Plague Treastise.” In Lister M Matheson, ed. Popular and Practical Science of Medieval England. (Colleagues Press, 1994): 263-282. In particular p. 273: “the south wynde greuyth the heeryng & hurteth the herte, by cause it openeth the poores of man & entreth into the herte[…]”

  3. Thus the Italian physician Mondino de’Liuzzi (ca. 1265-1326) claimed that the uterus’ second job (after reproduction) is “purging the whole body of superfluous, undigested blood.” He adds, “This applies to human beings only, because other animals do not suffer from the menstrual flux, since in them superfluities are consumed in [the production of] hide, fur, claws, beaks and feathers and the like, which humans lack.” From his work Anathomia Mundini. Text taken from Faith Wallis, ed. Medieval Medicine: A Reader. (University of Toronto Press: 2010), p. 236.

  4. For a thorough synopsis of the arguments against the Bubonic theory, see Robert E. Lerner, “Fleas: Some Scratchy Issues Concerning the Black Death.” The Journal of the Historical Society vol. 8:2 (2008): 205-228.

  5. See reference in previous note.

  6. The word superfluytee in Middle English can denote impurities or excess humors, such as bile or phlegm or blood.

  7. I’m unsure how to translate the reference to holes here — these last 3 words of this sentence are absent in the Thornton manuscript (ed. Margaret Sinclar Ogden, EETS 1938, repr. 1969, p. 52 — see part 1 of this blog post for more info). It’s possible I transcribed something incorrectly from the manuscript, though I’ve given it a second look. The Latin reads inter crura et corpus in crurium concauitatibus, or “between the legs and body in the cavities of the legs” – which I’m assuming refers to the inguinal region — home to a number of lymph nodes that could become inflamed by the black death or other diseases.

  8. The word here is “kynde” – to see its broader senses of nature, body, form, essence, see the definition. In Latin, this reads ad cor quod est principium et radix vit[a]e et humanam naturam taliter destruit et occidit — “to the heart, which is the beginning and root of life, and thus destroy and kill human nature.” I take the humanam naturam, here the source of the Middle English mannys kynde as likely the direct object of the verbs destroy and kill, given the accusative form (whereas principium and radix are nominative). (Latin nerds: check my work!)

  9. The full Latin here is sed quia ille locus est taliter op[p]ilatus, quod exire non possit procedit ad partem principaliorem ipsi cordi annexam que est epar — “But because that [cleansing] place is thus blocked so that it cannot proceed further, it proceeds to the principal part linked to the heart, which is the liver.”