When we start our Irish research, we soon come across the fact that many records were destroyed. Much of the record destruction came in the 1922 during the Irish Civil War when the archive was burned. The most valued, but not the only records, up in smoke were the 1841 and 1851 censuses, half the Church of Ireland registers, wills and administrations.
To try and fill in some gaps, we usually turn to the “Census Substitute” chapters in all the research guides. A census substitute is a record, any record, which fills in gaps by documenting a segment of the population in a given county or parish. These range from tax lists, to tombstone inscriptions, to such strange things as dog licenses. When they work to fill gaps, they really work. When they don’t then we simply move on. However, don’t assume any census substitute list is complete. None of them are close to being complete for the odd and scattered sources out there. A good census substitute list can come pretty darn close.