• Brittany
• Landévennec

Collection of Jean-Baptiste Colbert

• Computus
• Cosmology
• Calendar

• Various notes and anathema (added s. XII-XV?) (1r)
• Regulae mensium (1v)
• Brief history of computus, possibly compiled by, or in any case attributed to, a certain Etnoc auctor (1v)
• Calendar (2r-7v)
• Computistical and cosmological tables and diagrams (8r-18r)

Fols 18v-37r contain a heterogeneous collection of computistical and cosmological texts, including excerpts from Isidore's and Bede's works on these subjects, as well as numerous passages reflecting Irish computistical thought. In particular, the compilation presents:

• numerous chapters dedicated to the various divisions of time, mostly re-elaborated from the Irish De divisionibus temporum (passim)
• an equation between the annus naturalis and the annus magnus, very close to a passage of the Computus Hibernicus Parisinus of AD 754 (cf. the entries for Angers, BM, MS 476 and Paris, BnF, MS Lat. 6400B)
• an incomplete discussion of the noun uesper, based on the writings of Virgilius Maro Grammaticus (very close to analogous contents occurring in Paris, BnF, MS Lat. 6400B (25v)
• a textual lacuna (possibly due to the loss of a whole quire) between fols 25v and 26r
• a computistical argumentum for AD 1042, mentioning the death of Alanus rex Britanniae (30r)
• a mention of 6241 as the present annus mundi (= AD 1041/1042) (31v)
• added notes (s. XII-XV?) (37r-v).

• Certainly written in Brittany
• Numerous Breton saints in calendar

This MS can be dated thanks to the explicit reference to AD 1042 as the 'second year after the death of Alan, King of Brittany, son of Geoffrey' (secundo anno post mortem Alani regis Britanniae filii Ioffredi, plainly a reference to Alan III of Brittany, who died in AD 1040). Given that the script agrees with a mid-eleventh-century date, and given that a further dating clause for AM 6241 = AD 1042 occurs on fol. 31v, there is no doubt that this unit of Lat. 7418A was written in AD 1042 or shortly thereafter (for a different view, see Borst 2006: I, 274).

As for the attribution to Landévennec (or possibly one of its daughter-houses), this is confirmed by the mention of both the depositio and the dies natalis (i.e. the death) of Saint Winwaloe in the calendar, respectively at fols 3r and 3v (depositio sancti Uuingualoei abbatis for 3 March; natalis sancti Uuingualoei abbatis for 28 April). Moreover, this calendar mentions many other Breton saints, such as Gildas (29 January, fol. 2r), Paul Aurelian of Léon (12 March, fol. 3v), Corentinus of Quimper (1 May, fol. 4r), Ronan of Locronan (1 June, fol. 4v), Samson of Dol (28 July, fol. 5r), Edernus (1 September, fol. 6r), Melanius of Rennes (6 November, fol. 7r), and Macutis (15 November, fol. 7r). Finally, the brief history of computus that can be read on fol. 1v appears to have been compiled by, or is in any case attributed to, an individual named Etnoc auctor: Etnoc may well be a Breton name (cf. Bisagni 2019: 253–4).

The computistical materials occurring in this MS present significant insular and specifically Irish affiliations: among these, we may mention in particular a table at fol. 13r (on which cf. Lambert and Bisagni 2018), a fairly long section on the divisions of time at fols 20v–23v, a discussion of the different types of 'kindling' of the moon at different times of the year (subincensio, mediaincensio and superincensio) at fols 23v–24r, and a passage concerning the different forms of the noun uesper at fol. 25v (the contents of this passage derive from the writings of Virgilius Maro Grammaticus; for interesting parallels in other Breton MSS, cf. the entries for Cambridge, University Library, Dd.10.16, Paris, BnF, Lat. 6400B, and Paris, BnF, Lat. 13029 in the present Handlist; moreover, the uesper passage also occurs in Rome (Città del Vaticano), BAV, Reg.lat.49; cf. Bisagni 2020a: 43–4, n. 106). Even more important in this respect is the unique textual agreement between the discussion of the annus naturalis and solar eclipses at fol. 23v of Lat. 7418A and a passage of the Computus Hibernicus Parisinus of AD 754 dealing with the same subject-matter (fol. 277r of Paris, BNF, Lat. 6400B; cf. Bisagni 2019: 255–6). As a consequence, it seems that the eleventh-century scribe of Lat. 7418A copied computistical materials of Irish origin that had been circulating in Brittany at least since c. AD 900, and possibly well before that time.

Bisagni 2013–14: 122 (n. 23); Bisagni 2017: 32, 34; Bisagni 2019: 253–6, 261; Bisagni 2020a: 43–4 (n. 106), 49 (n. 120), 110; BnF Archives et Manuscrits; Borst 2004: 141, 150–4; Borst 2006: I, 274–6; Lambert and Bisagni 2018: 160 (n. 10).

• https://gallica.bnf.fr/ark:/12148/btv1b100323565