[4] Sir Robert Peel, while chief secretary to the lord-lieutenant of Ireland, encouraged Mason to undertake an Irish statistical work similar to that of Sir John Sinclair for Scotland.
The first volume of Mason's publication was issued at Dublin in octavo, with maps and plates, in 1814, under the title of A Statistical Account or Parochial Survey of Ireland, drawn up from the communications of the clergy.
[4] Mason compiled a Survey, Valuation, and Census of the Barony of Portnahinch in Queen's County.
This was printed in 1821 in a folio volume, and submitted to George IV during his visit to Ireland, as a model for a statistical survey of the whole country.
[4] A catalogue of books relating to Ireland, collected by Mason for Sir Robert Peel, was printed under the title of Bibliotheca Hibernicana, Dublin, 1823.