Catalogue description Ordnance Survey of Great Britain: Copy of the Down Survey of Ireland of 1655 to 1658

The maps from which these reproductions were made form no part of the official set of the Down Survey maps, and were never the property of the Irish Government. They appear to have been a set prepared for the private use of Sir William Petty, who executed the survey on behalf of the Commonwealth. They consist of selected sheets of the baronial survey only, not of the county survey. These sheets were being transported by sea to London for engraving in 1706, when they were captured by a French privateer. They were thence deposited in the Bibliotheque Nationale, Paris.

The maps from which these reproductions were made form no part of the official set of the Down Survey maps, and were never the property of the Irish Government. They appear to have been a set prepared for the private use of Sir William Petty, who executed the survey on behalf of the Commonwealth. They consist of selected sheets of the baronial survey only, not of the county survey. These sheets were being transported by sea to London for engraving in 1706, when they were captured by a French privateer. They were thence deposited in the Bibliotheque Nationale, Paris.

Fire in 1711 damaged the Irish official set in Dublin, leaving it defective. In 1734, an English researcher discovered Petty's maps in the Bibliotheque Nationale; and they were recognised as the best and most carefully executed record of the earliest survey of Ireland. Contrary to his contract, Petty had retained some of his working maps and the field books, which passed by testament to the National Library of Ireland.

The Down Survey was the legal basis for the identification of Irish lands. Where sheets were missing, reference was made to the maps in Paris. Copies of the latter were made in 1787 by General Vallency, and are in the custody of the National Library of Ireland, Dublin. The Irish Parliament, however, decided that as copies they were not admissible as evidence.

To rectify that situation, attempts were made at various times to prevail upon the French Government to restore those volumes to Ireland, but without success. In 1906, further negotiation was undertaken on behalf of the Government of Ireland by the British Foreign Office, in the general atmosphere of the Entente Cordiale, to obtain restitution of the maps, or, failing that, to investigate ways of obtaining satisfactory photocopies of them. As a result, permission was obtained for copies to be made at the Ordnance Survey Office, Southampton, in 1908. The originals were thereupon returned to Paris. A set of the reproductions was acquired for the library of the Public Record Office.