Jules Verne: Twenty Thousand Leagues Under the Seas

FIRST PART CHAPTER 4: Ned Land (continued)

"As many as that?"

"Yes, and since the atmosphere's pressure actually weighs slightly more than one kilogram per square centimeter, your 17,000 square centimeters are tolerating 17,568 kilograms at this very moment."

"Without my noticing it?"

"Without your noticing it. And if you aren't crushed by so much pressure, it's because the air penetrates the interior of your body with equal pressure. When the inside and outside pressures are in perfect balance, they neutralize each other and allow you to tolerate them without discomfort. But in the water it's another story."

"Yes, I see," Ned replied, growing more interested. "Because the water surrounds me but doesn't penetrate me."

"Precisely, Ned. So at thirty-two feet beneath the surface of the sea, you'll undergo a pressure of 17,568 kilograms; at 320 feet, or ten times greater pressure, it's 175,680 kilograms; at 3,200 feet, or 100 times greater pressure, it's 1,756,800 kilograms; finally, at 32,000 feet, or 1,000 times greater pressure, it's 17,568,000 kilograms; in other words, you'd be squashed as flat as if you'd just been yanked from between the plates of a hydraulic press!"

"Fire and brimstone!" Ned put in.

"All right then, my fine harpooner, if vertebrates several hundred meters long and proportionate in bulk live at such depths, their surface areas make up millions of square centimeters, and the pressure they undergo must be assessed in billions of kilograms. Calculate, then, how much resistance of bone structure and strength of constitution they'd need in order to withstand such pressures!"

"They'd need to be manufactured," Ned Land replied, "from sheet-iron plates eight inches thick, like ironclad frigates."

"Right, Ned, and then picture the damage such a mass could inflict if it were launched with the speed of an express train against a ship's hull."