"Yes, that's the base of the lungs, isn't it?" Eric queried.
"It is," the doctor answered. "Now when a man brings down the weight of the upper part of his body on his hands—the way Johnson is doing there—it means that about one hundred pounds of pressure is applied to those lungs, doesn't it?"
"Sure; fifty pounds on each lung," agreed the boy.
"You can see how that forces out nearly every bit of air in the lungs. Then, as soon as he leans backwards again, and takes off the pressure, the air rushes in to fill the lungs. That makes artificial breathing, doesn't it?"
"Of course."
"That's the whole secret of restoration; that, and keeping everlastingly at it."
"But if the Schaefer method is the best way," protested Eric, "I don't see why everybody doesn't use it."
"Such as—"
"Well, the Life-Saving end of the Coast Guard doesn't!"
"I don't say the Schaefer is the only good method," answered the doctor; "nothing of the kind. It's the one that suits us best." He stepped over to the prostrate man, never relaxing his vigilant watch for the first sign of life. Then, returning to Eric, he continued, "The Coast Guard uses the Sylvester method, doesn't it?"