"You see how it is," Frank said, "the Black Bear can never be pushed up over the falls, and we can never get her past the obstructions below, even by the use of dynamite.  If we could blow the those logs out of the way, the Indians would board us instantly.  We could give them only a charge or two of dynamite and a few shots before they would be inside.  Now' we can drift down the river in the Wolf without fear of entertaining man-eaters on board. They may get on top of the boat, but they can never get inside."