"Right." An echo. He can work with that. Maybe he's approaching this from just slightly the wrong angle. If the cup was making noise by rattling around on the floor, he'd calm the cup, setting off the chain reaction that drops the sound waves to nothing. The water is just the medium the waves travel in from the cup's vibration, just like sound in the air.

For a moment he watches the waves ripple across the surface of the cup, then focuses and lightly settles his hand on the rim. The ripples stop, but what's more, the steam rising from the coffee's surface dissipates as no more is produced from the liquid's own internal vibration. Enjoy your cold coffee, Will.

"I... think I did it," he says, as he withdraws his hand and lifts his eyes to meet Will's. "Felt strange, though. Like walking through mud."