I've written about the Revision Books a number of times. The Revision books for the Republic are located at the Valuation Office in Dublin (one of the repositories for the Dublin Research Trip), however, the books for the six counties of Northern Ireland were sent to Public Records Office of Northern Ireland (PRONI). The good news is that the PRONI has now digitized these books for Antrim, Armagh, Down, Fermanagh, Londonderry and Tyrone between the years 1864 to 1933.
Although some of the Revision Books were microfilmed by the LDS, I've always had problems using them, because the order of the filming was difficult to follow. When using the originals you begin with the Griffith's Valuation information using the townland, county and parish. A series of books will be brought out which contain the revisions. The individual revision books are bound together with the earliest book last working forward to the newer books.
You begin with the last book, checking the index for the page of the townland. You then match the number and letter reference (first column of Griffiths) to the entry in the townland and you should find a match to the Griffith's entry. I say "should" because there is always the possibility that something happened to your ancestor (moved, died) after the original printing.
Assuming your found your ancestor you note any changes. Here's where using the originals (as opposed to the microfilm) also is beneficial as each of the changes were done in a different color ink.
Using the PRONI images is straight forward. Begin by searching for the placename. I searched for Ballycrune in Down in the parish of Anahilt. The results listed five Valuation Books giving me the dates covered by each from 1866 - 1929.
Opening the first file, I paged to the index and found that the townland of Ballycrune began on page 37. There is no search by page number, but the page buttons allow you to move forward and back by single page or by 10 pages. Once I got to page 37, I needed to get to occupier 14a, my ancestor William Moag.
There were no changes from Griffith's to the listing in the first book, however in the second book, William Moag is crossed out and Mary is written in above (the end of the line shows the date as 1881). This shows that some event has taken place, in this case, the death of William and his wife, Mary has become the occupier.
In book 3, covering 1886-1897, the occupier changes from Mary Moag to James Rush in 1891. This corresponds to the year Mary and her children emigrated to the United States. The fact that the property moved to James Rush points to another area of research for me, as Mary's maiden name was Rush. Is James a brother?
This is a great addition to the digital records at PRONI. Now if the Valuation Office in Dublin would do the same thing <g>!
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