George Howard (Lord Morpeth) was Chief Secretary of Ireland. (In US terms that’d be like the Secretary of State). He left Ireland in 1841. 160,00 people signed a petition thanking him for his service to Ireland. Some gave their addresses.
So it’s a significant list of people alive in Ireland in 1841, with names and some addresses. Given that the 1841 census was destroyed, it acts as a sort of census substitute, providing some information at a period when other records are scarce.