Well Pi, by an amazing coincidence Yazz contacted me recently, as she is also a descendant of John and Barbara. My line descends from Barbara Mattingley's daughter, Frances (Fanny) Mattingley, who left Rotherhithe and turned up in records in Hartlepool, Co Durham on the eve of the 1851 census, the day she married William Shadforth of that town.
According to the information I have unearthed, John Torrison (aka Hans, Jan, Jans and various spellings of Torrison) was born on Ytteroy, a Norwegian island. He was baptised there on 12th November 1772, and was the son of Torres Reitan and Gunnil Hansdatter.