John O’Donovan’s Ordnance Survey Letters of King’s County, 1837 – 1838: Banagher, Clonmacnoise, Fercall, and Durrow. By John Dolan

Ordnance Survey of Ireland 1824 – 1842

John O’Donovan stayed in Banagher from 10-21 January 1834 where he was accompanied by Thomas O’Connor. As mentioned in a previous blog he used his time there to look at two historic sites in particular, in addition to his normal work. He first concentrated on Clonmacnoise, writing his first substantial and detailed letters on 15 January 1838. This followed on from his request that documents be sent from Dublin ahead of his arrival. He had visited Clonmacnoise and had collected a considerable amount of information about the church site and general area.

He first concentrated on the individual monuments on the site as detailed in earlier manuscripts and associated the monument to the relevant family names. His local contact was a man named Patrick Molloy but O’Donovan was sceptical about the accuracy of the information provided by him. In addition, he dealt with the map produced by Sir James Ware dated 1705; on this map Ware had identified 10 churches at Clonmacnoise, see below. For each monument O’Donovan checked the age of each as indicated in the Annals, checked the background of each one and compared that to a report in Petrie’s possession. Continue reading

John O’Donovan’s Ordnance Survey Letters of Kings County, 1837 – 1838: Scientific Survey, Clan Maliere and Placenames. By John Dolan

Ordnance Survey of Ireland 1824 – 1842

Townlands are the smallest official unit of administration in Ireland, followed by the Parish.  Our townlands are ancient divisions and some have existed under other names since pre-Christian times.

By the early 1800s, local taxes were based on the valuation of townland units. These valuations were based on hopelessly obsolete information and poor mapping, and it was necessary for the boundaries of townlands to be mapped accurately in order to provide a framework for new valuations. There are 64,642 townlands in the Republic of Ireland, with over 1,000 in Offaly.

The Duke of Wellington authorised a survey of Ireland in 1824 in response to requests from his brother, the Marquess of Wellesley, who was Lord Lieutenant of Ireland at the time. The task was given to Lt Col Thomas Colby and officers and sappers of the Royal Engineers with civil assistants. First established as a military office, all the staff were military employees until the 1970s, when recruiting of civilians started.

It was decided to carry out an experimental triangulation survey in 1824, using Ireland as a test area. When completed the Irish survey would be a model for Great Britain and other areas of the Empire. The aim of the survey was to standardise and anglicise the representation of the Irish landscape. Continue reading