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Grey archival boxes on a library shelf labelled as Ordnance Survey Letters with the relevant county.
Ordnance Survey Letters: divided by county and held in the Library of the Royal Irish Academy.

OS200: Spotlight on the Ordnance Survey Letters

This blog is the second in a series that marks 200 years since the first Ordnance Survey of Ireland.

Meadhbh Murphy

OS200 research project

This year marks 200 years since the first Ordnance Survey of Ireland. As home to a significant Ordnance Survey Archive, the Library of the Royal Irish Academy is pleased to be a partner in the OS200 research project.

The second instalment of this blog series will look at the Ordnance Survey Letters written by the surveyors while out in the field.

The OS Letters

The Royal Irish Academy holds a large collection of manuscript OS Letters comprising correspondence between John O’Donovan, MRIA (1806-1861), and other researchers employed on the Survey, to their Dublin headquarters as they travelled around the country. O’Donovan was appointed to the Ordnance Survey in 1830 and worked closely with Captain Thomas Larcom, MRIA (1801-1879), and George Petrie, MRIA (1790-1866), researching Irish placenames and establishing the authoritative form of names to be used in the maps.

There are one hundred thirty-seven volumes of letters, they exist for each Irish county with the exceptions of Cork, Antrim and Tyrone and are arranged by county and parish. The letters often record fascinating details of meetings and discussions with local people, folklore/tales behind the name of a particular place, commentary on events happening at the time and, of course, topographical information.

Handwritten letter.
Ordnance Survey Letters Containing information relative to the Antiquities of the County of Clare. O’Donovan to Larcom, 21 October 1839. RIA 14 B 23/5 (20)
Handwritten letter.
Ordnance Survey Letters Containing information relative to the Antiquities of the County of Clare. O’Donovan to Larcom, 21 October 1839. RIA 14 B 23/5 (21)

An Abbot, a Sorcerer and a Scallop

An example of such fascinating detail linking an abbot to monuments and folklore of a local area can be read in a letter written by O’Donovan to Larcom on 21 October 1839. O’Donovan was writing from Ennistimon, Co. Clare, about the history, genealogy, traditions, antiquities and place names of the surrounding areas of Abbey, Ardrahan and Finnivara. O’Donovan noted that Donough More O’Daly, Abbot of Boyle, lived near Finnivara House, ‘where a curious monument called Leacht of Donoghmore O’Daly is shown and also the site of his house and of a College over which he presided’. O’Donovan commented further…

‘Many wild stories are here told about Donogh More, but none sufficiently definite to be committed to writing, for tradition is so extravagant here as to make Donogh More O’Daly a brother of the Sorcerer Macámh Insi Creamha, whom he is said to have accidently killed by a “cast of a sharpened scallop”.’

The Sorcerer was a member of the Tuatha De Danann, a mythological race that inhabited Ireland after being banished from heaven because of their magical prowess.

Handwritten letter
Ordnance Survey Letters Containing information relative to the Antiquities of the County of Limerick. Notes by O’Donovan, 1840. RIA 14 D 18/6 (v)
Stained glass window with St Ita clothed in a purple robe and holding a book.
Stain glass window depicting St Ita in Ballylooby Church, Co. Tipperary. Courtesy of Wikipedia.

Poor Ity!

Other curious details, particularly about religious traditions, were also noted by the surveyors. In 1840, while collecting topographical information about the parishes of Rathronan and Killeedy in Co. Limerick, O’Donovan included references to St Ita and her association with Limerick. In O’Donovan’s over thirty pages of notes, he referred to a ‘primitive Irish church’ founded by Ita, who was also known as Ite, Ida and Mide, and inserted the following piece of associated history…

‘It was she [Ita] who suffered great tortures for the love of God; she permitted a daol to suck her unknown to all for a long time, until it grew to a size greater than that of a sucking pig, so that all her side was weakened, etc.’

O’Donovan included an explanation note about what a ‘daol’ was. He noted that a daol, or Darbh Daol, was ‘an insect well known and universally detested by the Irish people, because they believe that it feeds on human flesh in the Churchyards’. Today this insect is known as Devil’s coach horse beetle. The letters can give us an insight into the surveyors’ personalities, and here we can see a flash of O’Donovan’s when he noted this opinion about Ita and her death; ‘(Poor Idy was an Idiot! JO’D)’.

Green bound volumes on a library shelf.
O’Flanagan’s transcriptions of the Ordnance Survey Letters in the Library of the Royal Irish Academy.

Digital Images and Transcripts

Full transcripts of the letters were edited by the Rev Michael O’Flanagan (1876-1942) from 1927-1930 and a typescript set of this edition is held by the Library. Michael Herity, MRIA (1929-2016) published an updated transcription series of the letters which are available to consult in the Library, however they can also be accessed through your local public library.

The manuscript letters were disbound, conserved, microfilmed and digitised as part of the International Access to Academy Library Holdings Project, generously funded by Atlantic Philanthropies and completed in 2012. Digital versions of the letters are available on the Ask About Ireland website where they complement other resources such as Griffith’s Valuation and the OS Name Books. As part of the OS200 Ireland Mapped project the Library contributed digital scans of the microfilmed OS Letters along with detailed associated metadata.

Keep an eye out for our next blog to learn more about the OS archival material held here in the RIA Library and to find out about more about the OS200 digital resource.