Huck -- amphibian or mammal?

Comparing Huck (on page 173) he talks about how living on a raft is much more comfortable than living on land. I can see how Huck relates to this; He could feel that living on the raft gives him more freedom in the fact that he is close to the world. He is out more and can see, and is more one, with the whole world. In a town, one can easily feel cramped and closed in, in a small house inside a random small town in Arkansas. Also, it reminds me of when he was living with his father, and Huck had to be locked up, sometimes for weeks, by his dad, to ensure that he wouldn't run away. In that sense, one can notice how Huck would rather be outside, since he was constantly forced to stay inside a house for practically most of his young life. Also, I suppose that he doesn't like to be cramped up around crowds and he rather be on a boat with just a few people, Jim, the kind, the duke and himself.