had one of my terriers stuck in a quarry working , on day 2 a fella came across the fields, big tall gangly lad with overalls on & wearing wellies , he came up to me & said whats your problem lol , not knowing him i nearly decked him then he said he heard about the stuck dog & was a potholer ,beggar me this lad wormed his way in underground , feared for his safety , he saw the dogs head wedged between a V shaped rock stuck fast , the quarry owner arrived & with his machine bit by bit we dug away the rocks , eventually we got near enough to put a rope gently around the dogs ne