This leg is very long. The last fifteen meters is a vertical ascent into the air chamber. Goto Dengo had hoped that the natural buoyancy of their bodies would make this easy, even if they were on the verge of drowning. But as he is kicking up the narrow shaft, pushing frantically on the feet of Wing, who is above him and not going as fast as he would like, he feels a growing panic in his lungs. Finally he understands that he must fight the urge to hold his breath—that his lungs are filled with air at a much higher pressure than the water around him, and that if he doesn’t let some of that air out, his chest will explode. So against his instinct to save that precious air, he lets it boil out of his mouth. He hopes that the bubbles will pass by the faces of the men above him and give them the idea too. But shortly after he does it, they all stop moving entirely.