what saved jim and his mother after they had to flee the inn

Nothing in particular saves them. After failing to get help in the town they return and break into the chest belonging to Billy Bones. Mother and son take the money counted out so far as well as the oilcloth packet. As they make their way back to the village, they hear voices and see a lantern coming their way. Suddenly, Jim's mother faints, and in order to protect them from the quickly approaching lantern, Jim drags her under the arch of a bridge.