Review by William D Shannon.

O ’Cionnaith, himself a land surveyor, presents a vivid account of how Ireland became one of the most-mapped countries in the world, following the Cromwellian and Williamite land redistributions, which led to the Down Survey of the 1650s and the Trustees Survey of 1700-1703. The beneficiaries, the new landlords of the Ascendancy, wanted to know exactly what they had acquired, and the initial emphasis was on boundaries and basic land-measurement. By mid-century, though, the demand changed, with estate maps becoming as much show-pieces as management tools. Following the Act of Union, the government took an interest, with the Bogs Commission (1809-1814) scientifically surveying a substantial part of the island, the emphasis now being on topography rather than ownership, at a scale of two inches to the mile. Then, in 1824, the Ordnance Survey was diverted from Britain to Ireland, at first for taxation purposes, with the decision being taken to go with the scale of six inches to the mile. The result is an unparalleled national archive for the landscape historian and archaeologist.
Land Surveying in Ireland, 1690-1830, Finnian O’Cionnaith, Four Courts Press, £30, ISBN 978-1801510141