You probably spotted some errors in this posting long ago. The family you list were children of William and Dorothy (Swan) Dimmitt. They were grandchildren of the couple you name--William and Catherine (Bull)Dimmitt. I think your date for their son James may have been somehow mixed with the date of birth for William and Catherine Dimmitt's son, James, who was born 30 Mar 1737. And you probably know that Beal Dimmitt prob had no first name "Richard".