The 102-year old steam-powered, ocean-going tug, Hercules, is in dry-dock at Bay Ship & Yacht Co.’s Alameda yard for maintenance and repair work. Earlier this month she was towed across the bay from her berth at the Hyde Street Pier of the San Francisco Maritime National Historic Park, operated by the National Park Service. She will be in dry-dock at BS&Y for about a month for sandblasting and painting the riveted steel hull, replacing the boat deck, and other maintenance work at an estimated cost of some $500,000.