Whom do huck and Jim discover on the wrecked steamboat?

Huck and Jim couldn't escape the steamboat at first because their own raft had drifted away and was going far down river. Their only option was the robber's boat back up on the steamboat. When they got there, the robber's were loading it with goods they stole but went back for more. Huck and Jim took advantage of this time and took their boat to save themselves. Huck later sent someone else to rescue the robber's before they drowned on the ship.