The Ordnance Survey Memoirs of Ireland are are a unique source for the history of the northern half of Ireland before the Great Famine, as they document the landscape and situation, buildings and antiquities, land-holdings and population, employment and livelihoods of the parishes. The surveyors recorded the habits of the people, their food, drink, dress and customs. Details of ruined churches, prehistoric monuments and standing stones were also included.
Importantly, the Ordnance Survey Memoirs also provide copious
background information on the character and habits of the people who lived in
Ireland during the early part of the nineteenth century.
In some instances certain volumes of the series (particularly the volumes covering counties Antrim and Londonderry) will provide names and other useful details relating to individuals.
For example, the extract below is taken from Volume 11, concerning those living in the parish of Aghanloo: