Tomfox on Family Tree Circles

I have been researching the Fox line for years (off and on). I have discovered most of the folks until I get to the 17hundreds. Most of them were farmers. My grandfather was John fox 1873, Lackan Lower, Ballintemple, Clanmahon, County Cavan. His father was Michael 1841 to 1908; he also lived in Cavan. His father was Bernard 1800 to 1876 and then Patrick Fox Mar 1768 to 1819 in Westmeath. He is buried in Castlepollard, Westmeath. I have their vitals and the name of their spouses. I believe what I have is correct, but I would like to go further back. Any clues?