Owen,
I am slightly confused but see if any of this helps.
Hugh Henry was born in 1874 to Samuel Henry and Rachel Taylor who married in Macosquin Presbyterian Church in 1865. A Samuel Henry was Baptised in Garvagh Presbyterian Church in 1841. What appears to be the family are available in the 1901 and 1911 census, living in Ballinteer.
I have no way of determining if the two Samuels are the same man.
Regards