There are many errors in this document, first of all the prime factor of the Henthorn(e)s in Ireland belief is that it is simply a belief that James and John came to USA from Ireland.No one has any proof whatsoever, no documents, or where they sailed from.
There is also no proof that James who was born in 1705 ever had a brother John.In those days cousins and uncles were often referred to a brothers because they were brought up in extended families.
At the time that this James and John turned up in USA there were several sets of brothers and cousins all with the same names and time scale in the UK who disappeared at the time these two turned up in USA.
I would like to see some proof shown on this matter, I have researched in Ireland and cannot find that Isaac and Mabel ever had a son John, nor is there evidence that their son James ever came to USA.It is not feasible that someone who studied at University and had a good education would turn up and be a blacksmith.
Any clues out there would like to hear about them.