What happens when that wave travels, and it travels through water and the body, since the body is about 85% water, so there's very little attenuation unless it reaches an acoustic interface where the transmission of the wave is different. So when it reaches a place, say, a water-air interface or a water-stone interface, the transmission different, so some of that energy is absorbed, some of it is reflected. The energy that's absorbed actually goes through the stone and then when it tries to come out the stone at the end, again, it reaches, again, an acoustic interface and there's actually some distraction of the stone at the far end and some people have theorized that that actually has a major effect on the stone; it's not that you're actually crushing it by snapping it into itself, although there is certainly that aspect of it when the wave hits the front side of it but, actually, you're pulling it apart from the backside. This all occurs in microseconds and it results in fissures in the stones, multiple cracks, and the thing starts breaking up into little pieces. And it gets to the diagram of that at "A" is where there's the compressor force, "C" the wave has been absorbed into the stone, and "B" there's this tensile force that distracts the pieces from the stone.