Mathias nods his agreement at Sookie's question, which is a good one and something people don't often think to ask. "Divers are trained in various ways to clear their ears before they're allowed to be certified," he says. "That's what prevents damage to your sinuses or eardrums while the pressure changes. It's the same as being on an airplane and there's really no right way to do it. I'm sure you've done it before." Especially if she's noticed it while being in the pool.

He looks at the equipment behind him and shrugs, smiling faintly. "I received all I would need the year before last and then last year it gave me additional equipment to teach someone and several more oxygen tanks. I have to be careful with how much I use, especially since it gave me nothing like that this year, but there's plenty left. I ration it well."

One day he's going to run out, but until then, he's just going to keep hoping that the island gives him enough to get by with.