The Olde Jack gets it's name from a drinking vessel that the village was famous for, called a 'jacorra'. According to Wikipedia:
' (a) famed historical drinking vessel made of leather with a silver mounted enscripted band around the rim known as "the Jacorra" ("Corra" incidentally being an ancient name of the village). It was purported to be a challenge for any man to drink the full contents (just over a pint) of the Jacorra vessel in one go as quickly as possible but this wasn't as easy as it sounds due to the width of the vessels rim only allowing a thin trickle to pour from it. Unfortunately the whereabouts of the fabled Jacorra are no longer known, and is believed to have disappeared without trace some 120 years ago.
The people running the pub seemed very pleasant and it has a good reputation for food apparently, although we had a long way to travel so had to turn down their kind offer of something to eat. I hope to be able to see the plaques installed one day and try a meal there!