Down Survey - Survey Methodology

Survey Methodology

The survey employed about a thousand men and was performed with the promised rapidity, not by introducing new scientific methods, but by careful direction of the numerous subordinates among whom the labor was apportioned. Instead of using skilled surveyors, he completed the project using the now-unemployed - and cheap - soldiery. To enable unskilled soldiers to complete the task properly, Petty designed and built some simple instruments. The soldiers were only required to note the position of natural features and then use the chain provided to measure distances. Skilled cartographers then laid the information collected onto gridded paper at a central office in Dublin.

The method used was one of surveying the boundaries of parishes, the block of townlands inside those boundaries was not usually detailed. The scale used was generally 40 Irish perches to an inch (sometimes 80 perches), one perch equalling 21 feet (6.4 m). This land survey method was used widely in rural Ireland up to the nineteenth century and sorting out the precise details was left usually to the legal profession. As a result, the Down Survey is considered to be about 87% accurate.

Profitable and unprofitable land were distinguished, and there were abbreviated captions for arable, meadow, bog, woodland, mountain and several kinds of pasture, with area figures for each of these categories. Coverage of other subjects was uneven. In the parish maps, dwelling houses with the owners' names are entered in each townland.

Generally speaking, it was a survey of confiscated land. Parts of counties Roscommon, Galway, Clare and Mayo were not surveyed as they had been covered in the Strafford Survey of Connaught (1636–1640) and were anyway not to be confiscated.