The John B. King was a 140 foot wooden drill scow. In 1930 off of the northeast point of Cockburn Island while working in the main channel of the St Lawrence River she was hit by lightning. This set off the dynamite charges on the scow as well as those that had been placed underwater killing 30 of the crew. There were 11 of the crew that were rescued by the US Coast Guard that was in the area at the time of the explosion.
Approximately 80 feet down river from Buoy # 143A and west of CockBurn Island.
Depth 90 ft (27.4 m)