Answer:
A large oasis in the desert. Come with cash and leave with none.
I stand in one place yet I fill a whole room. I can be filled with molten rock and come in every hue.
A dragon's tooth in a mortal's hand, I kill, I maim, I divide the land.
Though desert men once called me God today men call me mad. For I wag my tail when I am angry. And growl when I am glad.
I have two body parts but am used to measure length. What am I?
I am the kind of an ant that's good at math. What am I?