By Deborah Hayden, OG(H)AM’s Co-Investigator
In a previous blog on this site, I noted that the use of ogam in early Irish manuscripts was closely associated with the development of texts on grammar and alphabets, subjects that would have formed a cornerstone of education for any medieval Irish scribe. By the late medieval and early modern periods, the transmission of ogam in such sources had also become intertwined with ideas about ciphers and secret writing, seemingly due to the circulation of a tract on cryptic varieties of the script known as In Lebor Ogaim (‘The Book of Ogam’. The inclusion of this material alongside texts that formed part of the rudimentary curriculum may help to explain why we find evidence for familiarity with ogam script and its cryptographic uses in what might otherwise seem an unlikely textual genre: namely, that of medical writing.
Over 120 medical manuscripts written in the Gaelic languages survive today, most of which were produced between ca 1400 and ca 1700. As a substantial – but as yet still underexplored – proportion of the total number of extant vernacular written sources from this period, they not only offer valuable insight into the early history of medical knowledge in Ireland and Scotland, but also into the historical lexicography of the Gaelic languages more generally. The practice of medicine across the Gaelic world centred around the activities of various learned families, whose members were often both experienced physicians and trained scribes who compiled medical manuscripts for their own reference purposes and frequently travelled considerable distances to access training or copy new material. While many of the texts preserved in the Irish-language medical manuscripts reflect engagement with scientific ideas and pedagogical trends current in the emerging universities of the European continent, some also reveal glimpses of a more local educational background. One example of this is the use of ogam script by certain members of the hereditary medical family known by the surname ‘Mac an Leagha’ (literally ‘son of the physician’, and therefore perhaps denoting a medical lineage of some antiquity) who were active in North Connacht around the turn of the sixteenth century.
Ogam and cryptography in the medical handbook of a Sligo physician
By way of illustration, we might begin with Dublin, King’s Inns Library MS 15, which is a collection of medical texts penned in 1512 by one Máel Eachlainn Mac an Leagha. This individual must have been a doctor of considerable standing, as he is in one instance styled ollamh in dá Mac Donnchaid or ‘professor’ to the two Mac Donnchaidh lords in Ballymote and Tirerrill, Co. Sligo. Like many physicians of the period, however, Máel Eachlainn clearly travelled from his home in search of training and reference works to copy: various notes in Kings Inns 15 indicate that he began writing the manuscript in Sligo, continued while visiting Kildare (in the present Herbertstown, about three miles from Newbridge) and completed it in Sligo upon his return. The manuscript contains an Irish translation of a surgical text by the fifteenth-century Italian physician Petrus de Argellata, as well as a tract on pathology that appears to have been compiled from existing Irish translations of at least four different sources, including works by well-known medical authors of the period such as Geraldus de Solo, John of Gaddesden and Bernard of Gordon.
While Máel Eachlainn Mac an Leagha thus shows himself to be fully engaged with teaching that circulated in medical works popular elsewhere in Europe, his scribal activity also offers an occasional nod to Gaelic tradition, as evidenced by the fact that he signs his name in ogam on two separate occasions in the Kings Inns 15 manuscript. The first such signature occurs on folio 107r, following a section of the pathological text concerned with eye ailments. Paul Walsh transliterated this inscription as OI MISE MAELEACLOINN MA-, noting that half of the last visible letter in the line (‘c’) has been torn away along with the conclusion of the entry. Walsh’s reading of the first circle in the line as the forfid symbol ᚖ (representing the diphthong oí) may be incorrect, however, since the circle does not intersect the baseline as one would normally expect, but rather is appended to one end of it. It is possible that the symbol was in this instance merely intended to serve as a distinctive type of ‘feather-mark’ indicating the start of the inscription. As Nora White has pointed out to me, a similar symbol appears on the ogam stone from Glanfahan, Co. Kerry (on which see here):

Máel Eachlainn again signed his name in ogam on folio 117v of King’s Inns MS 15, this time at the end of a section of the tract on pathology concerning afflictions of the tongue. Here the signature is complete and can be transliterated as MISE MAC ILLOINN MEC IN LEGA (‘I am the son of Illann, Mac an Leagha’):

One might observe that in this example (enlarged below), Máel Eachlainn superscribed four letters in Roman script and added dots to separate each distinct word. The use of punctuation and such ‘casual script-switching’ within words became increasingly common in manuscript ogam during the later medieval and early modern periods.

It is also interesting to note that Máel Eachlainn’s ogam signatures in King’s Inns Library MS 15 occur alongside other notes in cipher, suggesting that his use of the script might be linked to a broader interest in cryptography and perhaps also a familiarity with earlier texts that illustrated various types of secret writing systems. For instance, on folio 106v of the manuscript (again in the tract on pathology) he wrote his name in so-called ‘ogam consaine’, a common cipher, using conventional Roman script, wherein vowels are replaced by certain combinations of consonants (for further examples of this code, see here). On folios 67v and 112v, moreover, he signed his name using two other common ciphers (likewise in conventional Roman script) whereby each letter is to be read as the one after or before it in the alphabet, as illustrated below:

Both of the letter-substitution ciphers in question were circulating in Insular manuscripts by at least as early as the twelfth century, as is demonstrated by their inclusion in tables of exotic and cryptic alphabets from Oxford, St John’s College MS 17 (another manuscript that is also of interest for its ogam-related contents, as discussed here).
Ogam in a collection of materia medica
The King’s Inns Library manuscript is not the only medical source featuring ogam written by members of the Mac an Leagha family. Another example is Dublin, Trinity College MS 1323 (H 3. 4), a sixteenth-century vellum codex consisting of what were originally two separate manuscripts that mostly contain texts on the medicinal uses of various plants. Although the identity of the scribes responsible for copying this manuscript is not altogether clear, one of them might be a certain ‘Maghnus mac Gilla na Naem micc a Legha’ who is mentioned in a colophon on page 63. That this figure may have been a relative of Máel Eachlainn is suggested by two marginal ogam inscriptions on successive pages of the manuscript, one of which seems to have been written by Máel Eachlainn himself – indicating that at some point the book may have been in his possession. Thus at the bottom of page 32, the words ‘OLC SIN A MAILEACHLAOND MOIR’ (that is bad, great Máel Eachlainn’) are written in ogam, followed by legh sin (‘read that’) in Roman script:

While neither the scribe of this note nor the object of his criticism is explicitly identified, Máel Eachlainn Mac an Leagha would seem to be the addressee. At the bottom of the following page (33), moreover, Máel Eachlainn himself offers a response by way of a second ogam note. Although the intended value of some of the symbols in the middle of this inscription is uncertain, the beginning of the line might be read as COMORTUS […] RE […] and the final words as CONNLA MISE MAILEACHLAINN. The note as a whole may thus mean something like ‘a competition (of penmanship?) with Connla, I am Máel Eachlainn’. One might observe that in this instance, Máel Eachlainn seems to have used the forfid symbol ᚖ to represent the vowel ‘o’ (normally 3 strokes through the line) instead of the diphthong oí:

What we can glean from this second note, however, is that Máel Eachlainn was probably challenging someone named Connla to equal his scribal efforts, and one might therefore infer that this same Connla was the author of the first ogam inscription on page 32. Several years ago Paul Walsh established, on the basis of colophons and notes in the various extant medical manuscripts associated with the Mac an Leagha medical family, that Máel Eachlainn Mac an Leagha had a brother named Connla who was likewise a practising doctor in North Connacht, working primarily around the region of Magh Luirg (in modern-day Co. Roscommon). It is probable that this is the individual referred to here.
Connla Mac an Leagha and ogam in an Irish tract on uroscopy
Yet a third medical manuscript connected to the Mac an Leagha medical scribes is Dublin, Royal Irish Academy MS 445 (24 B 3), which consists of a number of bound fragments written around the turn of the sixteenth century. Among the 15 or so texts preserved in this source are a large prosimetrical collection of remedies for ailments affecting all parts of the body, arranged in head-to-toe order; a portion of a translation of Bernard of Gordon’s Lilium medicinae; an astrological tract; a lapidary (or treatise on the medicinal properties of stones and minerals); and a version of a pharmacological text by Walter of Agilon. Nearly all of this manuscript was written by Connla Mac an Leagha, brother of the aforementioned Máel Eachlainn.
Pages 31 and 32 of the RIA 24 B 3 manuscript contain a fragmentary treatise on the contents of urine. Uroscopy (the diagnosis of illness through examination of urine) was a common topic of discussion in medical manuscripts of the period, and the text in question, although incomplete and as yet unedited, appears to consist of an Irish version of fairly standard teaching on the subject found in Latin and other languages. What is interesting for our present purposes is the fact that the scribe of the Irish text (most likely Connla Mac an Leagha) repeatedly switched between Roman and ogam script in the middle of certain sentences:

For example, in lines 10–12 of page 31, when explaining the characteristic signs of a flux of menstrual blood, Connla wrote the first few words of the phrase AG DUL A NDATh dubh (‘becoming black’) in ogam script (with the exception of the final h in dath, which is written as a suprascript Roman character):

Connla’s use of ogam here thus does not appear to have any especially cryptic intent, but rather more likely represents the same kind of casual ‘script-switching’ we have seen above in one of Máel Eachlainn’s signatures. One might speculate that Connla has done this either for the purposes of personal amusement, or perhaps as a distraction from copying material that he considered to be quite technical or tedious in nature.
Ogam and medicine in the modern period
The sources outlined above, all penned by two doctors from the Mac an Leagha family during the early sixteenth century, are not the only surviving Irish-language manuscripts to feature contents of a medical nature alongside the use of ogam script. Another even more striking example of this phenomenon is found in National Library of Scotland, Advocates’ MS 50.3.11, which is a notebook – recently digitized for the OG(H)AM project – consisting of 66 pages of healing charms and prayers written entirely in ogam script. This source, which is thought to have been written in Kerry in or around 1849, has been dubbed ‘The Minchin Manuscript’ on account of the signature of its probable scribe on the title page, where the antiquarian J. F. Campbell also signed his name in ogam when the notebook came into his possession over two decades later:

As I am producing a full transcription of this source as part of my work for the OG(H)AM project, I will reserve detailed discussion of these particular encrypted cures for a future contribution to this blog. In the meantime, the image below of a common charm for toothache might serve to whet the appetites of our most avid readers. More on this soon!

Further reading:
De Brún, Pádraig, Catalogue of Irish Manuscripts in King’s Inns Library Dublin (Dublin: DIAS, 1972), pp. 36–43
Hayden, Deborah, ‘Attribution and authority in a medieval Irish medical compendium,’ Studia Hibernica, 45 (2019), 19–51
Nic Dhonnchadha, Aoibheann (2000) ‘Medical writing in Irish’, Irish Journal of Medical Science 169/3: 217–20 (repr. from LYONS, J. B., ed. [1999], 2000 Years of Irish Medicine [Dublin: Eireann Healthcare Publications], pp. 21–26)
Ó Conchubhair, Mícheál (ed. and trans.), An Irish Materia Medica (Tadhg Ó Cuinn) (interim version, 1991)
Purser, John (2019), ‘The cryptic background to the ogam manuscript NLS Adv. MS 50.3.11’, in Cànan is Cultar/Language and Culture. Rannsachadh na Gàidhlig 9, ed. by Meg Bateman & Richard A. V. Cox (Isle of Skye: Clò Ostaig), pp. 291–306
Walsh, Paul, ‘An Irish medical family – Mac an Leagha’, in Irish Men of Learning. Studies by Father Paul Walsh, ed. by Colm Ó Lochlainn (Dublin: Three Candles, 1947), pp. 206–18