We have found many marriage marks on the beams - as shown above. These are marks cut into beams in Roman numerals to show the carpenter where each beam should go. They are cut into the end of a beam and two with matching numerals will 'marry' up. The numerals also indicate whereabouts in the building the beams are to go.
This scribe system was overtaken by the square rule system somewhere between 1600 and 1640 which again would back up the supposition that the barns date somewhere in the mid to late 1600s.