Thank you for that, Shane. I can see the sense in moving these folks around.
Mary Jane Buchannon bapt 18 Jan 1855 Bumlin CI is pictured here on the left with my grandmother Maud Briggs born 1875 as a babe in the late 1880's.
From your helpful lead to Slater's Directory at
http://www.failteromhat.com/slater/0026.pdf I saw the entry for Mount Pleasant , and wondered if the JP had a barracks attached to his home. I then saw the mention of a police barracks in Strokestown and then looked for it on Google-Earth, where I made what could be an interesting discovery. The hamlet to the WSW of Strokestown is Lisroyne, and for years I have been looking for a place called Lisrain where my grandmother recalled her mother saying she last lived before she came to England.
I could not find the Griffiths mention in Boyle - perhaps I am using the wrong spelling. I've tried Buchanan, Buchannon, Buckanan but nothing works.
On another tack I did find a likely lad as future husband to Mary Jane - Alexander Briggs lodging at Ballymacbrennan, Magheralin, Lurgan, in County Down in 1864. This ties in with his report in the 1911 census as coming from nearby Mullaghglass, except that he thought it was Armagh. Boundaries may have changed. They married in England on 04 Aug 1875. In 1911 Mary Jane reported her birthplace as Roscommon, thus sparking off this search.
Regards, Alex