Lord Morpeth's Testimonial Roll 1841 is now available for searching and viewing on Ancestry. You can search either by name or browse by page.
Rather disappointingly, only a very small proportion of the pages or signatures give any indication of location, so it will be difficult for most researchers to pinpoint an ancestor with any certainly, even if the names match.
But in any case, beyond the thrill of finding a potential ancestor's signature in the document, such a discovery isn't, of itself, going to instantly progress your genealogy research.
However, the Morpeth Roll project's aim is to learn more about the document and the group of people who signed it. Very little is currently known, other than the document's intent as a fond farewell to a well-regarded statesman.
It'll become more useful as more is learned about the people who signed it.
Lord Morpeth Testimonial Scroll is a 412metre-long document made up of pages of paper gathered from across Ireland. Each page holds a number of signatures from supporters of Lord Morpeth who was leaving political office. It begins: 'To The Right Honourable Lord Viscount Morpeth: The Address of the Nobility, Gentry, Clergy, Merchants, Traders & People of Ireland.' It was originally estimated to hold some 250,000 names, but the indexing project has produced only (!) 158,000.
The Roll has been conserved and digitised in a collaborative project between NUI Maynooth and Ancestry.