 This is a sketch of what goes on in fracking to try to get gas and sometimes oil out of shale's way down below. So the surface of the earth, the air is up here, and down here, labeled Marcella's shale, is one of the layers that has lots of organic stuff trapped in it. And they have learned to drill wells that don't just go down, they can actually turn and drill huge distances horizontally. And then at some point what they'll do is they'll start pumping fluid into this at really high pressure. And as the pressure goes up and up and up and this tries to expand, eventually it breaks. And when it breaks, they squirt stuff into the cracks. There's a little close-up of this area shown up here. They'll squirt sand in so that the crack won't close. And then gas can sneak out between the sand grains and they can pump it out of this thing and put it in a pipeline or something else and we can burn it and use it in various ways.