THERE have been a number of developments concerning the tunnel uncovered by men working on Tavistock?s old Brook Street Arcade last month. Another mysterious tunnel has been reported by Paddy Moorhead, who contacted the Times about a subterranean passageway discovered more than 20 years ago. Friends of the family used to own a butchers on the premises now occupied by Gray?s on Market Street. After hosing down the rear patio, they noticed water disappearing between the paving and prised up a slab to see where it was going. They discovered a staircase descending into a long dark tunnel. Believing further exploration to be dangerous the Moorheads covered the entrance which been sealed ever since. As for the purpose of the Brook Street tunnel, historian Mary Freeman?s original suggestion ? that it was an underground reservoir ? now seems the most likely in light of the findings of a survey carried out by the Devon Mining Club. A team of cavers entered the tunnel on June 10 and found a number of items inside including the bowl of an old clay smoking pipe and a ?gad? or small chisel ? both of which are to be given to the museum. Although uncertain, the mining club believes the tunnel dates from the early Victorian period given the presence of drill holes bored into the rock. Mary Thompson, who once owned the Arcade, would like to point out that Rosa Bawden, a gypsy, was George Bawden?s mother, not his wife, and whose conservatory was decked out to look like a caravan. The old wagon works in front of the tunnel were used to store furniture, not the tunnel as previously stated.