As far as I can tell from a family tree of sorts drawn up by a distant relative (no documentation or proof provided),
I believe Henry's parents were Edmund Clarke (baptized 7/5/1824), married Hannah Tuffrey (on 15/10/1846).
After Hannah's death he married her sister Ester.
Edmund's father appears to have been a William born 1797, mother Elizabeth Warton (?)..
The family tree faded giant photo-copy) goes back to a John Clarke born in Bampton, Oxfordshire, in 1697.
It includes many Australian connections, and some dead-ends. My direct line is shown.