Boku and Goku gulped hard, they saw the rushing river in front of them.
A boulder rolled over and was carried away by the river flow before breaking apart after colliding with another rock. They believe from the bottom of their hearts that even elephants will be carried away by this current.
Water buoyancy is a magical thing and is the reason why can a ship weighing hundreds of tons float on water. Unfortunately, the laws of physics also apply in this world. No matter how heavy and strong Boku and Goku will still be carried away by the current of this river. This is because the water pressure at the bottom will be stronger and lift their bodies, as a result, their legs that do not touch the riverbed will float and their bodies will be carried away by the swift current of the river with a depth of two meters.