I located the photograph of a gravestone for John Pontius on Ancestry.com -- perhaps you can find it if you search there; but I have a copy if you want it.
The gravestone shows that John (Johann) Pontius was born 1718 in Alcace, came to America in 1738 and married in 1743 Catherine Zeller, daughter of Henry (I believe Heinrich) Zeller and Anna Marie Barigal.Died 1794. Their children and dates are listed on the back of the gravestone.
Let me know if you want me to send the photos, if you don't already have them.
I am also descended from Anna Catherine Zeller who married John Pontius, direct to my great grandmother Mary Ann C. Hassinger who married Peter J. Fellows.