"Tarzan is subjected to another trial in the swamp"
In this scene, Tarzan (Doug) is bound across the mud with one arm tied to a tree on one side of the pit and the other arm tied to a tree on the opposite side. His ankles are bound together and he is left to sink slowly into the bottomless mud. The ropes are too tight and too strong, but he struggles desperately to escape. Eventually, he sinks almost to his armpits. He cannot free his arms and his ankles are tied together, so there is simply nothing he can do but wait for the natives to return from their hunting trip. There is no telling what they will do to him if he cannot escape.