JenB - it was an option given in a search I did for Cornhill generally in the North East. Looking at Google maps, there seems to be streets in the city named Cornhill, although whether it was/is an actual district may have been my mistake. I was being lead by the family connection to Houghton-le-Spring in the vicinity, only 17 miles from this Cornhill, so appolgies if this has been a false trail.