Verschillende manuscripten op het Europese vasteland bevatten teksten over computus - de middeleeuwse wetenschap van tijdberekening - die doen vermoeden dat zij vanuit Ierland via Bretagne over het Karolingische rijk zijn verspreid. Specifieke elementen, zoals woorden en zinsnedes in de stijl van de Hisperica Famina, de Ierse naam Columanus (Columbanus?), en relaties met Ierse teksten zoals De ordine creaturarum, wijzen op een Ierse oorsprong van deze teksten. De manuscripten waarin zij worden gevonden wijzen zelf weer naar Bretagne van waaruit deze teksten verder moeten zijn verspreid. Nader onderzoek wordt uitgevoerd in het project Ireland and Carolingian Brittany: Texts and Transmission (IrCaBriTT).
When I stepped for the first time into the manuscript reading room of the Bibliothèque Nationale de France, in Paris, on a sunny autumn day of 2013, little did I know that I was about to encounter the codex that would determine the future direction of my research.
In an article published in 1984, Pierre-Yves Lambert briefly commented on two Old Breton glosses previously discovered by Léon Fleuriot in an early medieval manuscript containing a lengthy and heterogeneous miscellany of texts on computus—the medieval ‘science’ of time and time-reckoning. The manuscript in question was one of the several codicological units now constituting Paris, Bibliothèque Nationale de France (BNF), Lat. 6400B (to be precise, fols 249bisr–284v). This unit was written during the first half of the tenth century in one of the most important intellectual centres of the Loire Valley: the Benedictine monastery of Fleury at Saint-Benoît-sur-Loire.
Realising that no modern scholar had ever studied Lat. 6400B in relation to its computistical contents (as opposed to its few vernacular glosses), I decided to investigate this matter further, and in late 2013 I was kindly allowed by Dr Charlotte Denoël (curator of medieval manuscripts at the BNF) to study the original manuscript in detail. Six years on, Lat. 6400B has not finished yielding precious evidence for the transmission of computistical texts between Ireland, Brittany and the Carolingian Empire. The present article offers a brief overview of some of the main discoveries and developments that were set into motion by that first encounter with a very special manuscript.
The ‘Hisperic’ phrase tithis turgescentis dodrantem
During my PhD in Old and Middle Irish at the National University of Ireland, Galway (2004–2008), I had the privilege and pleasure of sharing many coffees, meals and stimulating discussions with several fellow doctoral students (many of whom have in the meantime become colleagues and excellent scholars); one among them, Immo Warntjes (now based at Trinity College, Dublin) was responsible for kindling my interest in early medieval computus—a topic on which we have collaborated since. For this reason, soon after realising the potential importance of Lat. 6400B for the study of the Continental transmission of Hiberno-Latin computistics, I discussed my preliminary findings with Warntjes, who, being an expert on the most technical aspects of computus, quickly detected (at fol. 277r) a crucial element for the identification and the dating of some of the most intriguing materials preserved in this codex: an anonymous computist’s attempt to elaborate a method for predicting solar eclipses.
In addition to being unique and exciting in its own right, this discovery also provided a precise date for a long continuous tract embedded in the compilation of Lat. 6400B (fols 274r-284r): the eclipse prediction makes it clear that its author was working in or shortly after the year 754. Moreover, the textual affiliations of this complex passage left no doubt that this tract originated in Ireland, and for these reasons Warntjes and I decided to label it Computus Hibernicus Parisinus of AD 754 (hereafter CHP).
Within a few days of Warntjes’s discovery, I identified another interesting textual element in the section that follows the eclipse prediction, at fol. 277v. The topic switches here to a technical treatment of one of the divisions of time: the quadrans, meaning ‘quarter-day’ (i.e. ¼ of one day). In this section, the discussion moves deftly between computus, grammar, etymology and biblical exegesis, focussing especially on the applicability of the term quadrans to calculations concerning the course of the moon as well as the rhythm of the tides. It is precisely in the section dealing with tidal theory that our anonymous Irish computist invokes a number of textual authorities such as the famous Isidore of Seville and the more obscure biblical commentator Philippus Presbyter. Among these, the following citation can be read: tithis turgescentis dodrantem (see image 1).
This curious phrase, here attributed to a mysterious prologus columna nigri, can be roughly translated as follows: ‘the powerful flood-tide of the swelling Ocean.’ Clearly, this is not ordinary Latin. Instead, the vocabulary of this citation belongs to the peculiar Insular style that often goes under the name of ‘Hisperic Latin’ (from the title of the most famous work written in this style, the Hisperica Famina): a language filled with rare lexical items, often borrowed from Greek or Hebrew, or newly coined through a variety of mechanisms of composition and suffixation, in a feast of striking linguistic inventiveness, or even playfulness. Words like tithis (originally the name of a Greek goddess of the Ocean, Τηθύς) and dodrans (here used not in its Classical meaning ‘three quarters’, but rather according to the specialised sense of ‘powerful incoming tide’) appear rather often in Insular—and indeed specifically Irish—works that may be characterised as ‘Hisperic.’However, there is one use of dodrans that offers a particularly close parallel with the quotation in Lat. 6400B. In his fifth letter, addressed to Pope Boniface, Columbanus offers a stylistically extravagant allegory of the arrival of the Christian faith to Ireland: in particular, Christ reached the island trans turgescentem dodrantem, ‘over the swelling flood’. In spite of a few differences, the textual match is clearly remarkable. For these reasons, in an article published in Peritia 24-25 (Bisagni 2013-14) I tentatively explained the plainly corrupt attribution to a prologus columna nigri as a scribal error hiding the name of Columbanus in the genitive. Thus, we may be dealing here with a prologus Columbani—a source which is otherwise unknown.
Conceivably, things could have simply ended there, in which case Lat. 6400B would have remained an interesting but essentially isolated example of Breton transmission of some rare Hiberno-Latin computistics. But things did not end there.
Further occurrences of the same Hisperic phrase in Carolingian manuscripts
Shortly after the discovery of the CHP, I found striking confirmations of the Breton circulation of Irish computistica analogous to those of Lat. 6400B in several other manuscripts, such as Angers, Bibliothèque Municipale, 476 (written in Brittany in the early tenth century) and BNF Lat. 7418A (written at Landévennec, in Western Brittany, in AD 1042). But the most surprising new data came to light when I turned my attention to Rome, Biblioteca Apostolica Vaticana (BAV), Reg.lat.123, a large codex written in the Catalan monastery of Ripoll in AD 1055. This manuscript, whose contents were in all likelihood copied from a miscellaneous collection on computus and cosmology put together in Fleury around the mid-ninth century, turned out to be a real treasure-trove of Hiberno-Latin computistica: for example, we find here excerpts which, taken together, constitute a nearly complete third copy of the Irish computistical tract De ratione conputandi, as well as innumerable textual matches with other Insular works that we may loosely describe as ‘scientific.’
Even more significantly, at fol. 77r of this manuscript I discovered a further occurrence of the Hisperic phrase tithis turgescentis dodrantem (see image 2). Surprisingly, though, this phrase is not cited here as part of a discussion of the quadrans like in Lat. 6400B; instead, it features in the conclusion of an argumentum (i.e. an algorithm) for calculating quot horis luceat luna in unaquaque nocte (‘for how many hours the moon may shine in whichever night’). Rather than presenting the usual recension of this argumentum (copied in numerous Carolingian computistical manuscripts), Reg.lat.123 offers what is plainly an augmented version, in which the discussion is extended to the relationship between the moon and the tides. The citation tithis turgescentis dodrantem appears precisely in this additional section, where it is misattributed to the already-mentioned biblical commentator Philippus Presbyter. As I have argued in an article published in Peritia in 2017, this interpolated version may have been compiled in Brittany (perhaps shortly after AD 800) and later circulated in scriptoria of the Loire Valley—especially Fleury—around the middle of the ninth century.
But again, this was not the end of the story. An even more interesting piece of evidence emerged in late 2016, when I discovered numerous large excerpts from a hitherto unknown Irish computistical tract in the manuscript Laon, Bibliothèque Municipale, 422, written in the first third of the ninth century in an undetermined scriptorium of Northern Francia, possibly in the area of Corbie. That we are dealing here with excerpts taken from an Irish tract is demonstrated not only by countless textual correspondences with Hiberno-Latin literature, but also by the occurrence of three words in Old Irish embedded in the main Latin text. Thus, in the chapter concerning the hour at fol. 39v, the anonymous author clarifies the linguistic distinction between the Latin terms hora (‘hour’) and ora (‘edge, limit’) by specifying that the latter word is the one corresponding to Old Irish or and imbel, likewise meaning ‘edge, border, limit.’ Moreover, in the section concerning the calendrical term idus (‘Ides’) at fol. 49v, a complex etymology is offered for the word in question: in this explanation, idus is associated with idolum (‘idol’), a word which is in turn explained as the ‘Greek’ equivalent of Latin formola (meaning ‘small shape’, but also ‘image made in a mould’). The noun formola is eventually translated by means of a bilingual Latin/Old Irish collocation: forma coirthe, i.e. ‘the shape of standing stones’, with standing stones being clearly taken as the equivalent of pagan idols.
Laon 422 contains an extraordinary number of fascinating passages deriving in all likelihood from what was originally an extensive Irish tract focussing on the divisions of time. We find here discussions concerning the various names of the sun, the relationship between different types of atom (atoms of matter, atoms of time, etc.), the theological nature of darkness, and even a brief text describing the strange places that the sun visits during its night-journey before fighting a daily battle against the Leviathan, the monster of the abyss who, swallowing and vomiting enormous amounts of seawater, triggers the rhythmical movement of the tides … More to the point, Laon 422 shares a significant amount of rare textual materials with the following computistical compilations: (1) an unpublished tract on the divisions of time contained in Cologne, Dombibliothek, 83-II (an important codex written at Cologne in 805), as well as, significantly, (2) many sections of Lat. 6400B (copied, as we have seen, from a Breton exemplar) and Angers 476 (written in an undetermined Breton scriptorium). In other words, Laon 422 preserves a substantial amount of the same Hiberno-Latin computistical materials that so far I had been able to find only in Breton compilations.
In particular, in the chapter concerning the quadrans (‘quarter-day’), the tract of Laon 422 discusses the specific use of the term dodrans in a passage from a certain prologo Colmani nigri pfuli: the phrase et tithis turgescentis dodrantem (see image 3). Plainly, the attribution of the citation is here preserved better than in Lat. 6400B. It is of course especially interesting that the attribution of Laon 422 contains the genitive of the Irish name Colmanus, namely the syncopated by-form of Columbanus. Moreover, this passage reveals that the word nigri (also occurring in Lat. 6400B) is an integral part of this mysterious author’s name. In short, there is no doubt that we are dealing with a Colmanus Niger (= Colmán Dub in Old Irish), ‘Colmán the Black’. As for the strange reading pfuli, this may well be a scribal corruption of praesulis, the genitive singular of praesul, a term often used for high ecclesiastical dignitaries such as bishops and abbots. The complete attribution of the Hisperic phrase can therefore be reconstructed as in prologo Colmani Nigri praesulis, ‘in the prologue of Colmán the Black, the prelate.’
How did these texts travel from Ireland to Breton and Carolingian scriptoria?
At this point, it may be useful to summarise the main data presented so far. A Hiberno-Latin computistical tract, written in Ireland in AD 754, survives in a single manuscript witness, the BNF manuscript Lat. 6400, copied in the scriptorium of Fleury from a Breton exemplar in the first half of the tenth century. In addition to preserving a very early attempt to predict solar eclipses, this tract contains the Hisperic citation tithis turgescentis dodrantem, whose style and vocabulary are perfectly compatible with the usus scribendi of Columbanus. This same citation also occurs in a lunar argumentum which, although probably compiled in Brittany in the late eighth or early ninth century, is now extant in two ninth-century manuscripts from the Loire Valley as well as in eleventh-century manuscripts from Catalonia and England. The Hisperic phrase can finally be found in a third text, where it is attributed to a ‘prologue’ by a certain Colmanus Niger (perhaps an alternative name for Columbanus?). The text in question is an Irish tract on the divisions of time, now surviving only as a series of excerpta copied in Laon, Bibliothèque Municipale, 422, an early ninth-century codex from Northern Francia containing an extensive computistical-astronomical compilation that shares numerous textual materials with Cologne 83-II (written in AD 805) and with two tenth-century Breton scientific manuscripts: Lat. 6400B and Angers, Bibliothèque Municipale, 476.
In view of all this, it should be clear that understanding the exact role played by Brittany in the transmission of Irish computistica is far from being simple. Let us take once again the Hisperic phrase tithis turgescentis dodrantem as our test-case: since the earliest manuscript evidence for it is actually found in a manuscript from Northern Francia (Laon 422), on the one hand it is perfectly conceivable that these texts may have reached first of all places such as Péronne or Corbie around 800, being transmitted to Brittany only at a later stage, perhaps through the proven strong links between Breton monasteries and the abbey of Fleury. On the other hand, we must also consider that the absolute chronology of the extant physical witnesses to a text rarely offers a perfect match with the actual path of its transmission, given that the survival of some manuscripts and the disappearance of some others are essentially random phenomena. Indeed, it seems at least equally plausible that these computistical materials travelled directly from Ireland to Brittany during the second half of the eighth century, subsequently reaching the scriptoria of Northern Francia around the early ninth century, again possibly through the crucial intermediary role of the monasteries of the Loire Valley—especially Fleury.
Although it is true that the bulk of the early medieval Breton production of texts and manuscripts is documented from the early ninth century onwards, we do possess good indications that ecclesiastical written culture had been developing in Brittany at the very least since the middle of the eighth century. For example, regardless of the specific date one may wish to assign to the Vita Prima of Saint Samson of Dol, this text proves that no later than circa 800—and quite possibly earlier than that—a Breton monastic writer could produce a full-blown hagiography respecting the conventions of the genre and containing citations from, and allusions to, a wide variety of Latin textual authorities, including Cassian, Jerome, Rufinus, Sulpicius Severus, Cassiodorus, Gregory the Great, and perhaps even Bede. The production of sophisticated works of this kind implies the existence of a considerable ‘infrastructure of learning’, namely scriptoria in which old books may be read and new books may be written by members of the Christian intellectual elite. If such an infrastructure and a literate intellectual elite existed in the late eighth-century Brittany—which is very likely—then it is virtually certain that Breton monastic scriptoria also possessed at least some works on computus, as this essential discipline allowed not only the correct calculation of the date of Easter, but also the establishment of the whole Christian calendar.
In light of the strong reputation for computus enjoyed by the Irish literati throughout the early Middle Ages, and since Bede’s magnum opus on time-reckoning (De temporum ratione, written in AD 725) became the standard textbook for this discipline only from the Carolingian age onwards, it seems reasonable to hypothesise that Brittany may have been particularly exposed to Irish computistical thought during the crucial decades of formation of Breton ecclesiastical written culture. Although one should of course be cautious not to project uncritically ninth-century data onto an eighth-century cultural reality which, unfortunately, is directly observable only to a very limited extent, it is nonetheless remarkable that all extant computistical manuscripts written in Brittany (or copied from Breton exemplars) between the ninth and the eleventh centuries contain at least some textual materials of Irish origin. Given that this is certainly not the case as far as other areas of Carolingian Europe are concerned, this statistically significant presence could conceivably be due to the existence of direct intellectual links between Ireland and Brittany prior to the increasing ‘Carolingianization’ of Breton written culture that took place during the ninth century, especially from the reign of Louis the Pious onwards.
At this stage it is not yet clear whether such links connected Ireland with several or even most Breton monasteries, or whether on the contrary they only involved a limited number of ecclesiastical foundations. The fact that the eleventh-century Landévennec manuscript Lat. 7418A presents specific and distinctive links with the computistical materials surviving in Lat. 6400B may be cautiously taken as an indication that such cultural connections were perhaps particularly strong with monasteries located in Western Brittany.
Conclusion: future directions
It is important to stress that much work remains to be done to test the hypotheses outlined in the previous section. Before 2013, the only Breton manuscript whose computistical contents had attracted some attention was Angers, Bibliothèque Municipale, 477—a codex especially famous for containing the largest collection of Old Breton glosses ever discovered. However, the discoveries made over the last six years have changed the picture considerably, and we are now dealing with a much larger corpus of manuscripts that can cast new light on the transmission of scientific texts between Ireland, Brittany and Carolingian Francia. This corpus is now at the centre of research carried out in the context of the project Ireland and Carolingian Brittany: Texts and Transmission (IrCaBriTT), directed by the present writer at the National University of Ireland, Galway, and funded by the Laureate Scheme of the Irish Research Council. In many ways, this material is very challenging. First of all, rather than focussing on a precisely defined group of sources, the IrCaBriTT project has to deal with an open-ended and ever-shifting body of manuscripts and texts—something which is both exciting and problematic. Given that early medieval computistical codices have been largely neglected so far, discoveries of previously unknown texts tend to be the norm rather than the exception, and this means that new evidence must often be integrated with the old, and provisional conclusions must be frequently revisited.
Here is a concrete example of what I mean. In late 2018 I examined the manuscript Madrid, Biblioteca Nacional, 9605, a computistical compilation written in the South of France, perhaps at Avignon, in the early eleventh century.image 4). While not documented anywhere else, this word can nonetheless be understood as an Old Breton compound meaning ‘star-prophet’ or ‘star-soothsayer.’ To my great surprise, after reading the first few pages I realised that some of the texts copied in this manuscript contain a number of Irish diagnostic features, as well as textual parallels with the Breton manuscript corpus outlined above. This first impression was soon confirmed by an interlinear gloss which I came across at folio 69r: in a brief tract concerning the etymology and the meaning of the calendrical term kalendae (‘calends’), also contained in Lat. 6400B and Angers 476 (as well as a few other manuscripts), we can read the curious gloss sterdigkiniat, placed just above the Latin word astrologus (see
This small discovery raises new questions. Indeed, what is an Old Breton gloss doing in an eleventh-century manuscript from Southern France? Was it originally inserted in the tract De kalendis in a Breton scriptorium, or by a Breton-speaking scholar working elsewhere? And what is the exact relationship between this gloss and the rest of the manuscript Madrid 9605, as well as between this whole manuscript and other plainly related codices such as Lat. 6400B and Angers 476? Could it be that this collection of computistical texts was compiled in Brittany and was later copied more or less mechanically (together with the single vernacular gloss) at Avignon?
It may be possible to answer questions such as these only through a detailed analysis of the whole corpus of manuscripts that share uncommon and highly distinctive computistical materials. It is important to stress that such a comparison should not consist only (or mainly) of collecting and assessing variants according to the usual philological techniques of ‘Lachmannian’ textual criticism. The point here is not so much the establishment of a stemma codicum or the reconstruction of an Ur-Text. Instead, the main interest of this corpus lies in the fact that it constitutes a complex network—a fact that carries considerable methodological implications. Thus, for instance, the Hisperic quotation tithis turgescentis dodrantem is so rare that its occurrence represents a virtually certain proof of a connection between the texts and manuscripts that contain it. Indeed, we should recall that this quotation occurs in three different texts: (1) the CHP of 754, (2) the tract on the divisions of time in Laon 422, (3) and the lunar argumentum concerning the hours of moonlight. This amounts to a total of (so far) six manuscripts: one for text 1 (Lat. 6400B), one of text 2 (Laon 422), and four for text 3 (BNF Lat. 5543; BAV Reg.lat.1260 and Reg.lat.123; Cambridge, Corpus Christi, 291—see note 11 for more details). Even setting aside momentarily the issue of the direction of this textual transmission, this evidence is already sufficient to draw a basic network linking up scriptoria in Brittany, the Loire Valley (especially Fleury), and the area of Corbie-Péronne in Northern Francia.
At this point, if, rather than limiting ourselves to a single rare feature (e.g. the Hisperic phrase), we multiply instead the number of significant Irish diagnostics (i.e. Hiberno-Latin textual elements which had very limited circulation in early medieval Europe), we shall obtain a network of growing complexity. For example, in addition to preserving the lunar argumentum discussed above, Reg.lat.123 also contains a single excerpt concerning the tides, taken from the seventh-century Irish cosmological tract De ordine creaturarum (cf. Diaz y Diaz 1972, IX, 4.28-7.55): this element establishes a significant connection with the Breton manuscript Angers 476, where we can read (at fol. 12) an unpublished short tract on tidal theory whose technical terminology (especially the striking collocation malina tenebrosa, referring to a specific phase of the tidal cycle) is directly based on that of De ordine creaturarum. In turn, Angers 476 shares many diagnostic features with Lat. 6400B, such as a number of distinctive and plainly related scribal errors, the same tract De kalendis where the gloss sterdigkiniat appears in Madrid 9605, an account on the creation of the sun and the moon possibly deriving from the CHP, etc. As for Lat. 6400B, in addition to sharing diagnostics with almost all the other codices of our corpus, this manuscript also contains an extremely rare equation between two ‘types’ of year—the annus magnus and the annus naturalis—which can also be found in the Landévennec codex Lat. 7418A.
The list of diagnostics shared by specific sub-sets of manuscripts could continue, eventually producing a network of connections so intricate that it may be best understood by means of a visualisation on a map, rather than through a narrative description. As I have pointed out repeatedly, much work remains to be done, so that the detailed cultural-historical implications deriving from this analysis are still unknown. However, on a more general level, it seems to me that even the non-directional web briefly outlined above can contribute to demolish the few lingering clichés that represent the early Middle Ages as a ‘dark age.’ Indeed, the remarkable diffusion and the continuous creative re-elaboration of Irish computistical sources evidenced by this corpus imply a striking degree of intellectual vitality and reveal the existence of a widespread cultural ‘internationalism’, at least among the intellectual elites. In other words, rather than being the isolated output of few exceptional individuals or schools, these texts speak in fact of a true ‘scientific community’ united by a powerful lingua franca—the Latin language—as well as by shared forms and practices of erudition. Interestingly, far from being confined to old ‘Roman’ areas or to foundations close (geographically and/or politically) to the core of Carolingian imperial power, this loose intellectual community also involved the only apparently peripheral world of the Celtic-speaking West—especially Ireland and Brittany.
On the one hand, the reconstruction of the mobility of ideas in the Carolingian age in relation to hitherto neglected fields such as computus or astronomy is still in its infancy. On the other hand, there is no doubt that this work promises to make an important contribution to the (re-)drawing of the map of connections between the many nameless scholars who, even amidst the endemic wars, turmoil and crises of the early Middle Ages, nevertheless managed to create and consolidate a form of European intellectual culture more united and cohesive than modern nationalisms, popular perception and recent political developments might lead us to believe.
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