Thanks! I have been using these now:). The 1841 Census form can be very confusing, but there are expanatory notes. What the Irish government did was include lines for entering names of deceased family members who had lived with the family during the past ten years (since June 1, 1832), and had died. Names, relationshp to head of household, date of death and even disease died from are included - if you can read the handwriting!
One man, Denis Nail, age 61 died in 1831 and was included, so he must have been born in 1760.
But not many fragments have survived. We can however, check these against the Tithe Applotments and Griffith's Valuations to try to tie families together.