John Downs

My Great- Grandfather was John Downs.  He was born 1/6/1834 in County Cork per my mother.  Per historical Census records he  immigrated in 1859 which would have made him 25 years old.  I am not able to find what ship he was a passenger on or what port he entered when he arrived.  I wonder if he came through Philadelphia because there was some Pennsylvania connection.  He married Anna Clifford on 4/16/1866 in Cleveland, Ohio, Cuyahoga County.  The marriage certificate looks like "Gowns" was the last name d/t bad handwriting.  They had two daughters, Johanna and Mary and then moved to Carlisle township in Lorain County, Ohio. They had seven more children. His parents, I learned from a death certificate was John and Mary McLaughton Downs.  I would like to know if he really was from County Cork, Ireland.