Qualifications : BE (
Location : Room 2.4,
Communications : Telephone +353-1-608-2029, Fax +353-1-677-2204, Email Dan.McCarthy@cs.tcd.ie
Computer Arithmetic, parallel architectures & processing, history of numbers and computation, computistics, lunar and solar cycles, astronomy, chronology, the chronicles of Eusebius, Jerome, Sulpicius Severus, Prosper, Bede and the Irish annals, the Paschal controversy.
Recent publications - click for abstracts:
1987 – ‘The "lost" Irish 84-year Easter Table rediscovered’
1993 – ‘Easter Principles and a Fifth-Century Lunar Cycle used in the British Isles’
1994 – ‘The Chronological Apparatus of the Annals of Ulster AD 431-1131’
1994 – ‘The Origin of the Latercus Paschal Cycle of the Insular Celtic Churches’
1995 – ‘A Re-evaluation of the Eastern and Western records of the Supernova of 1054’
1996 – ‘The Lunar and Paschal Tables of De ratione paschali Attributed to Anatolius of Laodicea’
1997 – ‘The Biblical Chronology of James Ussher’
1997 – ‘An Evaluation of Astronomical Observations in the Irish Annals’
1998 – ‘Astronomical Observations in the Irish Annals and their Motivation’
1999 – ‘The Chronology of the Irish Annals’
1999 – ‘The Status of the pre-Patrician Irish Annals’
2000 – ‘À propos du
synode de Whitby. Étude des observations astronomiques dans les Annales
irlandaises’
2000 – ‘The
Chronology of S. Brigit of Kildare’
2001 – ‘Topographical characteristics of the Vita Prima and Vita Cogitosii Sanctae Brigitae’
2001 – ‘The Chronology and Sources of the Early Irish Annals’
2002 – ‘The chronological apparatus of the Annals of Ulster AD 82–1019’
2003 – The ante-Nicene Christian Pasch: De ratione paschali – The Paschal tract of Anatolius, bishop of Laodicea
2003 – ‘Al-Khwarizmi’s sine tables and a Western table with the Hindu norm of R=150’
2003 – ‘On the shape of the Insular tonsure’
2003 – Annals & Chronology of Irish history
2003 – ‘The emergence of Anno Domini’
2004 – ‘The Original Compilation of the Annals of Ulster’
2005 – ‘Irish chronicles and their chronology’
2005 – ‘Chronological Synchronisation of the Irish Annals’
2005 – ‘Collation of the Irish regnal canon’
2008 – The Irish Annals: Their genesis, evolution and history
2009 – Review of Thomas M. Charles-Edwards, The Chronicle of Ireland: Translated with an
introduction and notes
2010 – ‘Bede’s primary source for the Vulgate chronology in his
chronicles in De temporibus and De temporum ratione’
2010 – Review of Nicholas Evans The Present and the Past in medieval Irish chronicles
2011 – ‘The
study and use of numbers in early Irish monasteries’
2011 – ‘A facsimile edition of the Annals of Roscrea’
2011 – ‘On the arrival of the Latercus in Ireland’
2012 – The Annals of Roscrea – A diplomatic edition
2013 – ‘Ruaidhrí Ó Casaide's contribution
to the Annals of Ulster’
2013 – ‘TCD
MS 1282 (The Annals of Ulster): a scholar's book and exemplar’
2014 – ‘The
illustration and text on the Book of Kells folio 114rv’
2014 – ‘Dalkey Quarry Tramway 1815-c.1855’
2014 – ‘The contribution of Armagh scholarship to the Annals of Ulster’
2015 – ‘The Chronology of Saint Columba's Life’
2015 – ‘On
reconstructing medieval Irish chronicles’
2016 – ‘Offprints of Ada Lovelace’s translation of Luigi Menabrea’s account of Charles Babbage’s Analytical Engine, incorporating an offprint by Babbage’
2017 – ‘Analysing and Restoring the Chronology of the Irish Annals’
2017 – ‘Representations of tonsure in the Book of Kells’
2017 – ‘The Paschal cycle of St Patrick’
List of Abstracts -
'The 'Lost' Irish 84-Year Easter Table Rediscovered' by D. Mc Carthy & D. Ó Cróinín, Peritia 6-7, (Cork, 1987-8), 227-42.
Abstract. The Paschal controversy
in the British Isles centred on the use of an 84-year Easter table, which was
abandoned by
Easter Principles and a Fifth-Century Lunar Cycle used in the British Isles by D. Mc Carthy, Journal for the History of Astronomy, xxiv, (1993), 204-24.
Abstract. The computational
principles underlying the Paschal table, or latercus, found in the
manuscript Padua, Bibl. Antoniana I.27 f. 76r–77v, are closely analysed and the
details of the mechansims of its embolism, bissextile and saltus are resolved
as closely as possible. With this information it is possible to eliminate all
of the scribal errors from the table and, thus restored, the table is presented
in full. From this can be seen that the
'The Chronological Apparatus of the Annals of
Abstract. This paper demonstrates
that the chronological framework of the Annals of Ulster is a combination of
two different systems: one based on January AD dating (nativity era), the other
based on March AD dating (incarnation era). This discovery explains the
discrepancies in the dates, and vindicates Ussher's analysis of the dating
criteria against Bartholomew Mac Carthy's later critique. The introduction of
March AD dating is pinpointed to the eleventh century, and is related to
contemporary political and ecclesiastical developments. The original
chronological apparatus is restored and some of the literary sources are also
identified. The date and place of compilation for the original are identified
as
The Origin of the Latercus Paschal Cycle of the Insular Celtic Churches by D. Mc Carthy, Cambrian Medieval Celtic Studies, 28 (1994), 25-49.
Abstract - The
A Re-evaluation of the Eastern and Western records of the Supernova of 1054 by A. Breen and D. Mc Carthy, Vistas in Astronomy, 39(1995), 363–79.
Abstract. The Chinese and Japanese records are our primary evidence of the supernova of 1054. But their evidence is not entirely consistent, and recent scholarly discussion of them has not yielded clear-cut results. We have therefore re-examined the original sources in some detail in order to determine their relative historical value and to arrive at as close a determination as possible of the appearance of the event itself. We have established from the Chinese sources that, on the authority of the Chief of the Astronomical Bureau at K'ai-feng, a guest star was first sighted between 9 June and 7 July 1054 to the north-west of Zeta Tauri; it became as bright as Venus, was visible in daylight for 23 days and did not disappear from sight until just before 17 April 1056. All this location, duration and brightness data points to this guest star as the supernova progenitor of the Crab nebula. When the Japanese texts are considered the date 4 July 1054 emerges as the most likely date for the first sighting of this supernova. Recent claims for both Middle-Eastern and Western European records are evaluated in the light of this result.
The Lunar and Paschal Tables of De ratione paschali Attributed to Anatolius of Laodicea by D. Mc Carthy, Archive for History of Exact Sciences, vol 49, no 4 (1996), 285–320.
Abstract. The lunar and Paschal
tables in the text De ratione paschali have been critically discussed by
numerous authors over the last 100 years without their inter-relationship ever
being considered or understood. Now, as a result of the discovery of the
‘The Biblical chronology of James Ussher’ by D. Mc Carthy, The Irish Astronomical Journal vol. 24, no. 1 (Jan. 1997), 73–82.
Abstract. Interest in James
Ussher and his chronological work saw a re-awakening as the date of the 22nd
October 1996 approached and it was realised that we were commencing the six
thousandth year from Archbishop Ussher’s estimated date of Creation, viz. the
beginning of the night of the 22nd October 4004 BC. In the popular
press some, playing on the inherent uncertainty of our existence, suggested
that Ussher had predicted that the world would end on the evening of 22nd
October 1996; thus the Irish Times headline
of this date ‘An early tea would be advisable as the world may end at 6 p.m.’.
However, examination of Ussher’s published works and manuscripts shows that
while he strongly reflected the millenarian beliefs of his own time that
significant events fell at intervals of one thousand years, he provided no
precise time of day for Creation and no prediction of the time and date of the
Last Day. In fact the precise time of Creation of 6 p.m. represents an
interpolation made by the
An Evaluation of Astronomical Observations in the Irish Annals by D. Mc Carthy & A. Breen, Vistas in Astronomy, vol 41, no. 1 (1997), 117–38.
Abstract. The astronomical
entries scattered through the Irish annals have been examined in a serious
astronomical context by R.R. Newton as part of his research into the
accelerations of the earth and moon, and by D. Schove and A. Fletcher, as part
of the Spectrum of Time project. They have never, however, been fully collated
and examined as a whole as this paper undertakes to do. What emerges is a body
of records from 442 to 1133 documenting eclipses, comets, aurorae, volcanic
dust clouds and possibly a supernova; from 627 to 1133 all of these records are
of observations made in or near Ireland, and most of them are accurate in their
chronological and descriptive details. Analysis of the details of these records
implies that, at least from the seventh to the eleventh centuries, careful and
sustained observation and recording of astronomical phenomena were conducted in
some Irish monasteries, and it is clear that the underlying motive was
religious and specifically eschatological, i.e. to detect the first signs of
the end of time as prognosticated in the Book of Revelation. Critical
examination of this data allows us to throw new light on the circumstances of
the Synod of Whitby in 664, to identify the date of the eruption of the volcano
Eldgjá in
Astronomical Observations in the Irish Annals and their Motivation by D. Mc Carthy & A. Breen, Peritia 11 (Cork 1998), 1–43.
Abstract. This paper presents the same material as is presented in An Evaluation of Astronomical Observations in the Irish Annals, but it concentrates on the textual and historical issues relating to the material. Thus the original texts of all the entries are reproduced and a much more detailed textual treatment is given of the entry found under 1054 and the historical background to the Synod of Whitby and its relationship to the solar eclipse of 664.
'The Chronology of the Irish Annals' by D. Mc Carthy, Proceedings of the Royal Irish Academy 98C6 (1998), 203–255.
Abstract. The chronology of much of the Irish annals has hitherto been most uncertain, particularly from the fifth to the eighth centuries, which has seriously hindered their use as historical sources. This paper demonstrates that the oldest chronological apparatus preserved in these annals is the kalend-plus-ferial and, further, that the ferial data recorded in the Annals of Tigernach and Chronicon Scotorum may be restored and constitutes a cogent sequence from the Incarnation up to the middle of the seventh century. When this chronology is calibrated using events for which we have indepedendent chronological information it emerges that thirteen kalends were removed from the Iona Chronicle between the AD years 424-664, and thus we may recover the nearly all of the original chronology of that chronicle. Collation of this chronology with those of the Annals of Ulster and Inishfallen shows that both preserve derivative and corrupted chronologies; this collation has been made available on the Web at -
https://www.cs.tcd.ie/Dan.McCarthy/chronology/synchronisms/annals-chron.htm
A copy of this paper is available as a PDF file for down-loading from the Royal Irish Academy website.
'The Status of the pre-Patrician Irish Annals' by D. Mc Carthy, Peritia 12 (1998), 98–152
Abstract. This paper investigates the question of the sources and dates of the pre-Patrician material found in the annals of Tigernach and Inisfallen, firstly by reviewing all the contributions which have been made over the last century. From this it emerges that whereas analysis of the non-Irish material has resulted in significant progress, exploration of the Irish material has proven both difficult and singularly unproductive. Consequently a careful examination of the chronological structure and textual details of part of the Roman imperial succession has been made, which discloses that it had been compiled by conflating Eutropius’ Breviarium ab urbe condita with Jerome’s Chronicle. Next, textual collation with Bede’s Chron. Mai. shows that, rather than the annals having been derived from Bede, as has been generally assumed, in fact both pre-Patrician AT and AI, and Bede, all derive from a common source. The evidence shows that, while Bede’s text is generally less textually corrupt, the annals preserve both more of the content of the original source, and its chronological apparatus as well. Next, examination of the Alexandrian episcopal succession found in AT shows that it had been derived directly from Rufinus’ Ecclesiastical History, and details of the errors suggest that it was he himself who constructed it. Finally, examination of the Hebrew succession in Bede and AI reveals divergences from Jerome’s chronology that could not plausibly be the work of Bede, but are all appropriate to Rufinus. Hence, as a working hypothesis it has been proposed that Rufinus compiled a chronicle in the first decade of the fifth century, which travelled to Ireland with the 84-year Paschal table of Sulpicius Severus, whence it was used in Iona in the mid-sixth century as the basis for the Iona Chronicle. Tables of both the Roman imperial reigns and the Hebrew succession are available at:
https://www.cs.tcd.ie/Dan.McCarthy/chronology/synchronisms/annals-stat.htm
'À propos du
synode de Whitby. Étude des observations astronomiques dans les Annales
irlandaises' by D. Mc Carthy & A. Breen, Annales de Bretagne et des Pays
de l'Ouest vol 107, no.3 (Rennes 2000).
This is essentially a translation to French of the paper published in 1997 as An Evaluation of Astronomical Observations in the Irish Annals in Vistas in Astronomy, vol 41, no. 1 (1997), 117–38.
'The Chronology of S. Brigit of Kildare' by D. Mc Carthy, Peritia 14 (2000), 255–81.
Abstract. This paper undertakes a critical chronological and textual analysis of all the annalistic entries bearing on the life of S. Brigit of Kildare. From this it emerges that AT and CS have best preserved the chronology originally given to Brigit in the Iona Chronicle which placed her death at AD 524 aged 86 years, whereas AU and AI transmit a later tradition subsequently interpolated into the Iona Chronicle that she died aged 70 years. It is argued that the author of the original Iona Chronicle entries was S. Columba, a competent computist and near-contemporary of Brigit, and hence that his chronology of Brigit is trustworthy. To check this, a chronological evaluation of the earliest surviving Vitae S. Brigitae reveals that the chronology of all the individuals found jointly in the Vita I and the annals is consistent, implying that both sources have transmitted a chronology which is essentially correct, a result which supports the historical priority of Vita I over Vita II. Finally examination of the context of Cogitosus’ date for Brigit’s death shows that he aligned it to correspond with existing non-Christian celebrations already held in Kildare.
'Topographical characteristics of the Vita Prima and Vita Cogitosii Sanctae Brigitae' by D. Mc Carthy, Studia Celtica XXV (2001), 245–70.
Abstract. The two oldest lives of St. Brigit of Kildare are the anonymous Vita I and Cogitosus’ Vita II, but scholars have disagreed as to which is the oldest. However evaluation of all of Vita I’s topographical references reveals that it maintains a virtually continuous location for her entire active adult life. It thus mirrors topographically the chronological consistency with annals already demonstrated for Vita I. Since these topographical and chronological elements are evidently independent they must derive from a common tradition which is earlier than that of the annals, that is, the later sixth century. On the other hand Vita II is topographically blank but when Vita I is used to locate Vita II’s parallel episodes, all but three are located in Laigin or in Kildare, in conformity with Cogitosus’ emphasis upon the priority of the church in Kildare. Examination of the episodes given in the time-frame of Cogitosus himself shows that he was deeply involved in technical and practical matters concerning the monastery in Kildare, of which he was most likely both prior and master craftsman. When the Vita II episodes which are more detailed than the parallel Vita I episodes are examined, it clearly emerges that the additions are all appropriate to Cogitosus’ style of composition, namely, enhancing his source with a combination of imagined technical details and pious interpretations. This leads to the conclusion that Cogitosus based Vita II directly and solely on Vita I. Finally consideration of Donatus’ account of the Vita Brigitae by Animosus suggests that Gregory’s Dialogues lib. I,7 inspired both of the names Cogitosus and Animosus as pseudonyms for the author of Vita II. These results substantially support the conclusion that Vita I was composed by Ailerán of Clonard, and it is an abridgement of an earlier, now lost, Vita by Ultán of Ardbraccan.
'The Chronology and Sources of the Early Irish Annals' by D.
Mc Carthy, Early Medieval
Abstract. Chronological
divergence between the different early Irish annals has hampered use of their
many unique records of events in
The chronological apparatus of the Annals of Ulster AD 82–1019 by D.P. Mc Carthy, Peritia 16 (2002), 256–83.
Abstract. The view represented by Mac Airt and Mac Niocaill in their 1983 edition of AU that the annals of ff. 12–14 of TCD 1282 are indeed part of the Annals of Ulster has recently been vindicated. Analysis of the chronological apparatus of ff. 12–14 reveals that their author was responsible for the introduction of Dionysiac epacts and continuous Anno Domini into the Irish annals. He accomplished this by an extraordinary series of interpolations into the pre-Palladian section of the Iona Chronicle that he used as source, demonstrating both his computistical skill and profound indifference to historical chronology. By AD 431 his apparatus was accurately synchronised with all the Dionysiac chronological criteria, and he continued with it, re-ordering many events through the fifth and sixth centuries. In the seventh century he omitted a single kalend, which put all his subsequent apparatus in arrears by one year. Collation of AU with the other annals indicates that his compilation continued to c. 1019 and was completed shortly after 1022. This compilation is identified with AU’s Liber Cuanach, and Cuan hua Lothcháin (†1024) is proposed as the author.
The ante-Nicene Christian Pasch: De ratione
paschali – The Paschal tract of
Anatolius, bishop of
Abstract. Very little
contemporary evidence for the diversity of Christian Paschal practice that
preceded the Council of Niceae has survived. A unique exception, however, is
the Paschal tract of Anatolius, bishop of
Al-Khwarizmi’s sine tables and a Western table with the Hindu norm of R=150 by D.P. Mc Carthy & J.G. Byrne, Archive for the History of Exact Sciences 57 (2003), 243–66.
Abstract. This paper demonstrates that the influential ninth century astronomical tract of Ibn Musa al-Khwarizmi incorporated two sine tables, one to norm R=150 at fifteen degree intervals reproduced from an Indian source, and a second to norm R=60 at one degree intervals derived directly from the chord table included by Ptolemy in his Almagest. Consequently it concludes that the norm R=60 sine table preserved in the twelfth century Latin translation of al-Khwarizmi by Adelard of Bath is indeed the work of al-Khwarizmi, and is not an interpolation as recent scholarship had maintained. An analysis of the one-second errors in the R=150 table preserved in the Toledan tables shows that it was derived by scaling and truncating an R=60 sine table, and the details suggest this to be the work of al-Zarquali of Cordoba, and that he used an edition of al-Battani’s sine table as his source.
On the shape of the Insular tonsure by D.P. Mc Carthy in Celtica xxiv (2003), 140–67.
Abstract. In 1639 bishop James Ussher reviewed all of the evidence relating to the tonsure worn by clerics belonging to the British, Scottish, Pictish and Irish churches from the fifth to the ninth century, and concluded that it was semicircular in shape. In 1703 the Benedictine scholar Mabillon, citing only a portrait of uncertain provenance found in a St. Amand manuscript proposed that the Insular tonsure consisted of entirely denuding of hair the front part of the head, while the back was unshorn. Whilst Mabillon’s hypothesis was unsupported by any evidence and in complete conflict with all of the sixth, seventh and eighth century evidence, some coming from eye-witnesses, nevertheless it has largely prevailed in modern times. This paper carefully reviews the early medieval evidence and proposes that the tonsure was triangular in shape, resembling a Greek delta. This hypothesis is tested against graphic portrayals of tonsures found in some Insular Gospel texts and it emerges that texts associated with Columban monasteries, where the tonsure is known to have been worn, do indeed confirm this triangular shape.
Encyclopaedia entries Annals and Chronology of Irish history in B. Lalor (ed.) The Encyclopaedia of Ireland, (Dublin 2003) pp. 33 and 193 respectively.
Abstract. Brief accounts of the Irish annals and of the basis for the chronology of Irish history.
The emergence of Anno Domini in G. Jaritz & G. Moreno-Riaño (edd.) Time and Eternity – The Medieval Discourse (Brepols: Turnhout, 2003), 31–53.
Abstract. Since at least the eighth
century the system of counting calendar years from the supposed year of the
birth of Christ (ab Anno Domini) has been attributed to Dionysius
Exiguus, a Scythian monk in
‘The
Original Compilation of the Annals of
Abstract. Ever since 1861 when in his Manuscript Materials Eoghan O’Curry published James H. Todd’s opinion that the first three folios of the TCD manuscript of the Annals of Ulster (AU), i.e. TCD 1282 ff. 12–14, represented ‘a fragment of an ancient copy of Tigernach’, the virtual consensus amongst scholars has been that these folios were interpolated and hence that AU commenced at AD 431. However this paper undertakes a critical examination of the paleographical and codicological evidence and demonstrates that these folios were in fact written by Ruaidhrí Ua Luinín, the principal scribe of the MS, and they were bound to the following gatherings in the first stitching of the codex. Furthermore their foliation by James Ware in the earlier seventeenth century implies that there were then eleven folios preceding f. 12, which itself commences at AD 82. This then implies that when originally compiled TCD 1282 commenced either at or near Creation, as do the closely related Annals of Boyle. Moreover critical comparison of the annals transcribed by Ruaidhrí Ua Caiside from TCD 1282 to Rawlinson B. 489 ff. 1–32ra, with the numerous interpolations into TCD 1282 in the hand identified as H2 in the edition of Mac Airt and Mac Niocaill, shows this to be the hand of Ua Caiside and not that of Cathal Mac Maghnusa as has been repeatedly asserted. Finally, examination of the concluding folios of TCD 1282, viz. ff 130r–143v, shows that these were also written by Ua Caiside, as James Ware had asserted in 1639, and in them Ua Caiside developed a steadily improving imitation of the hand of Ua Luinín. Hence the conclusion that this MS is complete at the end and that it was written as far as 1504 by Ua Caiside in approximately that year.
‘Irish
chronicles and their chronology’, the present edition online since 2005 at www.scss.tcd.ie/misc/kronos/chronology/synchronisms/annals-chron.htm
Abstract. This article provides a short introduction to the two
important chronological traditions employed in medieval Ireland. The earlier
was the kalend tradition, which was the original Annalistic chronological
apparatus, employing the kalends of January (1 January) to identify the
commencement of each successive chronicle year. The later was the regnal canon
tradition, which employed a table of the regnal years of the supposed
successive kings ruling in Ireland. The article provides links to a substantial
account of the kalend tradition and to the year-by-year synchronisation over AD
1–1590 of its best witnesses, namely, the Annals of Tigernach, Chronicum Scotorum, the Annals of
Roscrea, Ulster, Inisfallen, Boyle, Connacht, Loch Cé, and Mageoghagan’s Book
(alias Annals of Clonmacnoise). Links are also provided to a substantial
account of the regnal canon tradition, and to a parallel collation of the
regnal years of its significant witnesses; these include synchronisms,
chronological poems, various editions of Lebor Gabála, Michéal Ó Clérigh’s Seanchas
Riogh Ereann and Annala
Rioghachta Eireann (alias Annals of the Four Masters), Seathrún Céitinn’s
Foras Feasa ar Éirinn, and Ruaidhrí O’Flaherty’s Ogygia.
‘Chronological Synchronisation of the Irish
Annals’, the present edition online since 2005 at www.scss.tcd.ie/misc/kronos/chronology/synchronisms/Edition_4/K_trad/K_synch.htm
Abstract. This article briefly outlines the
early use of the kalends of January to sequence a chronicle by Rufinus of
Aquiliea (†410), and its subsequent continuation in Iona, Clonmacnoise, Armagh,
Derry, and along the river Shannon. It provides an extensive discussion of the
significant features of the principal collated sources, namely, the Annals of
Tigernach, Chronicum Scotorum, the
Annals of Ulster, Inisfallen, and Mageoghagan’s Book (alias Annals of
Clonmacnoise), and brief discussions of the Annals of Boyle, Roscrea, the
Fragmentary Annals, Bede’s Chronica
maiora, and the Annales Cambriae.
It examines the problem of seven kalends missing at AD 425–431, and a further six
kalends missing over AD 612–664, and proposes a restoration of these. From this
is derived the synchronised chronology from them over AD 1–1590 based upon the
chronological criteria of the Annals of Tigernach, Chronicum Scotorum, and the Annals of Ulster, Connacht, and Loch
Cé. Over AD 1–1590 tokens of the annalistic entries are collated in parallel,
sometimes comprehensively, at other times using sampling. A chronological
survey of Michéal Ó Clérigh’s Annals of the Four Masters is presented demonstrating
that its chronology is chaotic relative to all of the older annalistic sources,
and for this reason it has not been included in the collation.
‘Collation of the Irish regnal canon’. the present
edition online since 2005 at: www.scss.tcd.ie/misc/kronos/chronology/synchronisms/Edition_4/RC_trad/RC_collation.htm
Abstract. This article describes the ten
principal witnesses to the regnal canon, namely the Laud synchronisms,
chronological poems by Flann Mainistreach, Gilla Cóemáin and Gilla mo Dubda Ó
Casaide, various editions of Lebor Gabála, Michéal Ó Clérigh’s Seanchas Riogh Ereann and Annala Rioghachta Eireann (alias
Annals of the Four Masters), Seathrún Céitinn’s Foras Feasa ar Éirinn,
and Ruaidhrí O’Flaherty’s Ogygia. It describes and provides a
parallel collation of these regnal years for each reign, and discusses their
significant correspondences and differences. Where possible it identifies the
location chosen by each source for the year of the Incarnation.
The Irish Annals: Their genesis, evolution and
history, Four Courts Press, (Dublin
& Portland, OR, 2008), xvi + 416 pages with illustrations.
This is the first book to
systematically survey the manuscripts of the Irish Annals, the unique mediaeval
Christian chronicles which were maintained in
Review of
Thomas M. Charles-Edwards The Chronicle of
‘Bede’s primary source for the Vulgate
chronology in his chronicles in De
temporibus and De temporum ratione’,
in Immo Warntjes and Dáibhí Ó Cróinín (edd) Computus
and its cultural context in the Latin West – Proceedings of the 1st
International conference on the Science of Computus in Ireland and Europe,
Galway, 14–16 July, 2006 (Brepols, Turnhout 2010), 159–89.
Abstract. Mommsen’s 1898 assumption that
Bede had compiled the Vulgate chronology of his chronicles in De temporibus (DT) and De temporum ratione (DTR) has been
simply reiterated by scholars ever since. But critical collation of Bede’s
chronicles with the Irish Annals leads to the conclusion that their common
features, including their Vulgate chronology, derive from a common source that
originated in a chronicle compiled by Rufinus of Aquileia †410. By the year 538
Rufinus’ chronicle was being continued in
A review
of Nicholas Evans The Present and Past
the in medieval Irish chronicles (Boydell Press, Woodbridge, Suffolk 2010),
pp. xv + 289, published by The Medieval
Review and available online at:
https://scholarworks.iu.edu/dspace/bitstream/handle/2022/9494/10.10.04.html?sequence=1
‘The study and use of numbers in early Irish monasteries’, chapter thirteen in Charles Doherty, Linda Doran, and Mary Kelly (edd) Glendalough: City of God (Four Courts Press, Dublin, 2011), 223–37.
Abstract. The presence in the manuscripts of early Christian
Ireland of sophisticated geometrical constructions, complex numerical
structures embedded within texts, and computistical works discussing the
different computations of the date of Easter, all attest to a refined interest
and capability in numbers and their uses in early Irish monasteries. The Latercus, compiled in circa 410 by
Sulpicius Severus in southern Gaul, is the earliest of these Paschal traditions
known in
‘A facsimile edition of the Annals of Roscrea’, by Bart Jaski and Daniel Mc Carthy available online at www.scss.tcd.ie/misc/kronos/editions/AR_portal.htm
Abstract. The Irish chronicle known to
modern scholarship as the ‘Annals of Roscrea’ is found only in the manuscript
The Annals of Roscrea – A diplomatic edition,
by Bart Jaski and Daniel Mc Carthy, (Roscrea People: Roscrea, Co.
Abstract. The Irish chronicle known to modern scholarship as the
‘Annals of Roscrea’ is found only in the manuscript
This edition is based upon the online edition, ‘A facsimile edition of the Annals of Roscrea’, see above, and it was published in a limited edition of seventy-five copies with the generous assistance of the Roscrea People, Roscrea Heritage Society, and George Cunningham of Parkmore, Roscrea.
‘On
the arrival of the Latercus in
Abstract.
The
hypotheses published in 1733 by van der Hagen regarding the supposed
computistical parameters and Roman origin of the Latercus, the 84-year Paschal
tradition followed by the early Insular churches, and the alleged forged status
of Paschal tracts cited by Insular authors are profoundly mistaken when viewed
beside the evidence of the copy of the Latercus discovered by Dáibhí Ó Cróinín
in Padua MS I 27. Furthermore, the computistical features of this
‘Ruaidhrí Ó Casaide’s contribution to the Annals of Ulster’ in Seán
Duffy (ed.) Princes, Prelates and Poets in Medieval Ireland - Essays in
honour of Katharine Simms (Dublin: Four Courts Press, 2013), 444-59.
Abstract. Ruaidhrí Ó Casaide, †1541, a
member of a Fermanagh medical family and vicar of Clogher, made three major
scribal contributions to the compilatiion of the two principal manuscripts of
the Annals of Ulster, Trinity
College, Dublin, MS 1282 (MS H), and Oxford, Bodleian, Rawl. B. 489 (MS R).
Namely, he wrote numerous marginal and interlinear additions to MS H, he wrote
the years AD 1489–1504 in concluding folios 130r–143v of MS H, and he
transcribed from MS H the years AD 431–952 in folios 1–32r of MS R. However, a
comprehensive survey of the occurrence of Arabic numerals, alternative entries
with contrasting chronology, and temporal emphatics such as ‘hoc anno’ and ‘in
bliadhain-si’, discloses that Ó Casaide was also the editor of the exemplar
used by Ó Luinín to write folios 12–130r of MS H. Consideration of the various
temporal horizons in MS H and MS R shows that MS H was written by Ó Luinín and
Ó Casaide between circa 1495–1505, while MS H was transcribed to MS R by Ó
Casaide and Ó Luinín in circa 1505–7, and the entries were then continued by Ó
Casaide until his death in 1541, the additional entries being written for him
by twelve different amanuenses.
‘TCD
MS 1282 (The Annals of Ulster): a scholar’s book and exemplar’ in W.E. Vaughan
(ed.) The Old Library - Trinity College Dublin 1712 -2012 (Dublin: Four
Courts Press, 2013), 33-9.
Abstract. A
short essay reviewing the contributions of both Ruaidhrí Ó Casaide and Ruaidhrí
Ó Luinín to the writing and compilation of the two principal manuscripts of the
Annals of Ulster, namely Trinity
College, Dublin, MS 1282 (MS H), and Oxford, Bodleian, Rawl. B. 489 (MS R).
This shows that when transcribing MS H into MS R Ó Casaide introduced textual
and orthographical changes to the entries. A summary account is also given of
the publication of various editions of these annals, starting with Rev. Charles
O’Connor in 1826, through to the edition of Seán Mac Airt and Gearóid Mac
Niocaill in 1983.
‘The illustration and text
on the Book of Kells folio 114rv’, Studies in Iconography 35 (2014),
1-38.
Abstract. This paper presents the
evidence that the illustration on folio 114r of the Book of Kells showing two
similar figures flanking Jesus, and supporting his arms, represents the
disciples James and John watching with him during his Agony in the
It is further shown that this is one of a number of instances in the
Book of Kells where warmth is expressed towards John, and ambivalence towards
Peter, an attitude found in the Paschal tract De ratione paschali which provided the authority to the early
Insular churches for celebrating Easter on luna fourteen. Moreover, it is shown
that on folio 32v Jesus is portrayed with the triangular Insular tonsure
imposed. These heterodox identifications rule out as possible provenances for
the Book of Kells all those Insular churches that had adopted the Paschal and
tonsurial traditions followed by the Roman church, which rejected luna fourteen
and prescribed the coronal tonsure. This effectively leaves only Kells, whose
foundation is described in the Annals at 807 as ‘the new monastery of Colum
Cille’, as the only plausible location for the compilation of the Book. The
magnificence of the Book suggests that it was commissioned for the church of
this new monastery at Kells, which was completed in 814.
‘Dalkey Quarry Tramway
1815-c.1855’ in David Gwynn (ed.), Early Railways 5, (Clare,
Abstract. An account of the horse-drawn tramway and funicular system constructed 1816–17 at the instigation of the Scottish engineer, John Rennie, to transport granite from the quarry at Dalkey, county Dublin, to face the piers for the harbour designed by Rennie at Dún Laoghaire, about two miles away. The tramway was very robustly designed and constructed, and continued in service until the middle of the nineteenth century.
‘The contribution of
Abstract.
This paper examines specifically the contributions of
‘The Chronology of Saint Columba's Life’ in Pádraic Moran & Immo
Warntjes (eds), Early Medieval
Abstract. Between Adomnán’s Vita Columbae and Bede’s account in his Historia Ecclesiastica, Saint Columba’s
life and missionary career are the best recorded of all early Irish
ecclesiastics. Further, and in great contrast to his fifth-century British
missionary predecessor, Saint Patrick, Columba’s chronology has not been the
subject of controversy in modern times. At least from the seventeenth century
scholarship has been almost unanimous that Columba died in 597, a date that
derives from Adomnán’s assertion that he died on Sunday, and that he left
‘On reconstructing medieval Irish chronicles’
by D.P. Mc Carthy – unpublished.
Exposition. In 2013 the journal Early Medieval Europe published Roy Flechner’s article, ‘The
Chronicle of Ireland: then and now’, in which he endorsed Kathleen Hughes’ 1972
hypothesis of a ‘Chronicle of Ireland’, and added a number of his own
hypotheses. In this he found it necessary to reiterate and approve dismissive
criticism of my own published analysis of the origin and evolution of the Irish
Annals. As I considered that both Hughes’ and Flechner’s hypotheses rest upon
mistaken assumptions and that I was entitled to a right of reply to his
criticism, I submitted an article entitled ‘On reconstructing medieval Irish
chronicles’ to Early Medieval Europe on
27 August, 2015. On 26 November, 2015, the Editors notified me by email
that Reviewer 1 disputed my right of reply, with which view they concurred, and
so they rejected my submission. Here is the link for the pdf of my submission
of ‘On reconstructing medieval Irish chronicles’. A postscript is
suffixed to this submission dated 6 July, 2016, which reproduces the Editors’
email, including the Reviewers’ ‘Comments to the Author’, so that scholars may
judge the situation for themselves.
Abstract. Examination
of Kathleen Hughes’ 1972 hypothesis of a ‘Chronicle of Ireland’ reveals that
her primary assumption that the Annals of Ulster represent ‘the most complete
version of the Irish annals’ was mistaken. This assumption has strongly influenced
the understanding of early Irish annals by most subsequent scholarship.
However, this article contends that the kalend and ferial structure of the
Clonmacnoise group of annals embodies the earliest surviving witness to the
early annals. The methodology of Roy Flechner’s recent analysis of the
compilation, motivation, and classification of the ‘Chronicle of Ireland’ is
also examined and found to be misjudged.
‘Offprints of Ada Lovelace’s translation of Luigi Menabrea’s account of Charles Babbage’s Analytical Engine, incorporating an offprint by Babbage’ by D.P. Mc Carthy – unpublished.
Exposition. This paper was submitted to the IEEE Annals of the
History of Computing
on 14 September 2016. On 31 October 2016 an email from the Chief Editor, Dr
Nathan Ensmenger, included two reviews, the first recommending publication and
the second recommending rejection. Dr Ensmenger concurred with the second
reviewer so that the article was not published. Here is the link to a pdf of my
submission Offprints_of_Ada_Lovelace’s_translation.
In this pdf a postscript has been suffixed to the submission reproducing Dr
Ensmenger’s email, including the two reviews, so that scholars may judge the
situation for themselves.
Abstract.
This article examines textual and bibliographical aspects of Ada Lovelace’s
article translating and annotating Luigi Menabrea’s account of Charles
Babbage’s Analytical Engine, published in the Scientific Memoirs of 1843. Textually it concludes that the preface
to her translation, although apparently attributed to the ‘Editor’, was
actually compiled by Babbage himself, and in it he reviewed the history of both
his Difference Engine and Analytical Engine. However, as published the account
of the Analytical Engine is incomplete because the concluding section dealing
with Babbage’s conflict with the British Government was refused by the editor
of the Scientific Memoirs.
Consequently, Babbage published this concluding section soon afterwards in the Philosophical Magazine of 1843. For the
remainder of his life Babbage regarded this publication as his ‘defense’, and
he placed it first in his un-published ‘History of the Analytical Engine’.
Bibliographically it is shown that offprints of both publications circulated
amongst friends and contemporaries of both
‘Analysing and Restoring the Chronology of the Irish Annals’ in Ralph Kenna, Máirín MacCarron & Pádraig MacCarron (eds), Maths Meets Myths: Quantitative Approaches to Ancient Narratives, (Switzerland: Springer International Publishing, 2017), 177 – 194.
Abstract. Substantial annalistic chronicles of Irish affairs exist in a number of medieval versions, but they exhibit considerable variation both in the sequences of events and the chronological apparatus used to link each year to the Julian calendar. Of these, the Anno Domini years of the Annals of Ulster have been principally relied upon by historians. However, these are demonstrably incorrect from the seventh to the eleventh centuries. Moreover, its remaining chronological data of ferials and lunar epacts at the kalends of January, that is, the day of the week and the age of the moon on 1 January, are almost all interpolations by a later scribe. On the other hand, the Annals of Tigernach and the Chronicum Scotorum have only kalends and ferials marking the commencement of each year from the Incarnation up until the mid-seventh century. Because these kalends and ferials are susceptible to scribal miscopying they were dismissed by historians and textual scholars as “hopelessly confused”. However, analysis of the 28 year cycle of the ferials reveals that they possess a powerful error-correction property. Exploitation of this property has enabled the restoration of all the missing kalends and erroneous ferials of the Annals of Tigernach and Chronicum Scotorum, as well as of the closely related Annals of Roscrea, known collectively as the Clonmacnoise group. Using computer table structures, the kalends and ferials and events of these three have been synchronized with the Anno Domini years over the range AD 1–1178, and this tabulation, with cross-references to the other Irish medieval annals, has been made available online at www.irish-annals.cs.tcd.ie. In this chapter the process of analysis, correction, and synchronization is illustrated, taking the year of the death of St Patrick as an example.
‘Representations of tonsure in the Book of Kells’, Studia Celtica 51 (2017), 89–103.
Abstract Four Insular documents from the seventh and eighth centuries show that a major controversy took place amongst the Insular churches regarding the shape of the tonsure worn by clerics. Those who followed the customs of the Roman church wore a coronal tonsures, oval or circular in plan, while those belonging to some earlier Irish and British churches wore a delta tonsure, triangular in plan. This paper critically examines six figures in the Book of Kells proposed to have been illustrated with tonsures. Three of these at ff. 32v, 34r and 273r all show Jesus with the delta tonsure. The haloed figure above the second Canon table at f. 2v is likewise shown with the delta tonsure. On the other hand, the mounted figure at f. 255v is shown with a coronal tonsure and is explicitly coupled to the words ‘unum’ and ‘peccauerat’ of Luke 17:1 and 17:3 respectively. In Luke 17:1–3 Jesus censures all those who give cause for temptation to sin, saying it would be better that they were cast into the sea with a mill-stone about their neck. Consequently, by this graphic presentation of the coronal tonsure the compilers of Kells expressed their strong disapproval of it. A sixth figure at f. 182r proposed by James McIlwain in 2008 to be illustrated with the coronal tonsure is shown in fact to represent Pontius Pilate wearing an oval cap. Thus the five illustrations of tonsure in the Book of Kells represent a graphic polemic, exalting those who wore the delta tonsure, but directed against those who wore the Roman coronal tonsure.
‘The Paschal cycle of St Patrick’ in Immo Warntjes & Dáibhí Ó Cróinín (edd) Late Antique Calendrical Thought in the Early Middle Ages – Proceedings of the 3rd International Conference on the Science of Computus in Ireland and Europe – Galway, 16–18 July, 2010 (Brepols: Turnhout, 2017), 94–137.
Abstract. Notwithstanding
the substantial corpus of early mediaeval references to St Patrick and his
works, the only account we have of a paschal cycle associated with him is that
provided by Cummian in his letter to Ségéne of Iona and Bécán the hermit in c. AD 633. In this letter Cummian
identified himself and his community with Patrick, but he furnished only
limited technical details for both Patrick’s cycle and the cycle he indicated
that he and his community had recently adopted. However, critical examination
of Cummian’s account shows that Patrick had adapted the 532-year paschal cycle
compiled by Victorius of Aquitaine in AD 457, and that this was the cycle that
Cummian’s community and other influential southern Irish churches had resolved
to adopt at the synod of Mag Léne in c. AD 630. Consequently, Cummian’s account
of Patrick’s cycle, the earliest attested reference to him, holds significant
implications for both the chronology of Patrick’s mission to
Page updated 18 April 2018