P51mus wrote:
And if you shaped the clay boat wrong and "infused it with fire", then put it in water, it'd sink. Like if you made a clay ball and fired it up. No straddling of lines there. Straight to earth, despite the fire.
One way of explaining this away within the elemental paradigm would be to realize that a boat is really a container of sorts, and that the contents of the container will influence the natural height/depth which it attempts to attain. Since a ball isn't a container but rather a solid piece of Earth, obviously it would sink.
To elaborate on the "boats as containers" idea:
When boats (and most other containers) are full of air, they naturally tend toward higher elevations than water, and float upon it. However, if a boat springs a leak and fills with water, then it will sink, since it has lost the added levity of the air which was influencing it previously.
Possible objection:
Okay, you mention a boat "springing a leak," but what's happening when a boat springs a leak? A hole has opened in its bottom, water and air are meeting, and the water is moving to become higher than the air which was there previously. What's up with that, huh?
Hmm. Well, what you have to realize is that actually, when you're putting the boat-container into the water with the air in it, you're taking some of that air further down than it would go naturally. (c.f. Crashman's post; if only half of the boat is above the surface, the other half must be below the surface of the water, which is lower than air is normally willing to go.) At the same time, you're forcing a like amount of water to go elsewhere, but as can be proved by the smooth surfaces of puddles, left to itself water tries to maintain a perfectly smooth face where it meets with air. So when the boat-container is ruptured, the water happily rises back to the height it had before being displaced by the boat-container and its air, and the air happily rises and allows the water to take its place. Of course, this upsets the balance of elements within the boat-container; less air and more water means it now has a greater tendency to sink, and sink it does.
Pyromancer, not sure what to say to your ideas yet. If I think of anything, I'll let you know. :-)