Looking for information on Samuel Rippie born in Donegal, Ireland in 1775 son Samuel Rippie born 1801 died in 3 Jan 1879 in rothesay, bute, Scotland
No Rippie/Rippy households in Donegal in the 1850s in Griffiths Valuation. There were only a couple in the whole of Ireland and they were in Co Tyrone.
http://www.askaboutireland.ie/griffith-valuation/index.xml?action=nameS…
The 1901 Irish census has just one Rippie/Rippy in Co Donegal in it. She was Katie Rippy, born Scotland, who was lodging with a family in Corrafrin.
http://www.census.nationalarchives.ie/pages/1901/Donegal/Knock/Corraffrin/1198701/
If you get no other clues, it might be worth searching in that area.