SI Vault
Peter R. Gimbel
November 17, 1958
In the depths of the colder oceans lies a strange and fearful world which few men have explored. Here is the story of deep-ocean free diving
Decrease font Decrease font
Enlarge font Enlarge font
November 17, 1958

The Wildest Province Of The Sea

In the depths of the colder oceans lies a strange and fearful world which few men have explored. Here is the story of deep-ocean free diving

View CoverRead All Articles View This Issue

A water surface has the quality of a veil, perhaps the most marvelous veil in creation. It is the natural barrier between the two worlds of the planet earth, the world of air and the world of water. Its character is in the eyes of the beholder: infinitely hostile to some and vastly mysterious to others. For most people it has both qualities. The artfulness of the surface veil lies in the fact that it suggests with purity and truth the temper of the world it hides, while actually revealing nothing. Over the shallow reefs of the tropic seas, it is pale and enchanting and full of sun; beneath it lie the coral reefs and white sand bottoms, and in those light-blue, sunny waters swim brightly colored creatures. It is for the most part a cheerful world full of dazzling color. But the surface of the temperate oceans is a hostile veil. It is dark and wild, especially far from land. It is fitting that it is so, for the world it conceals is not friendly either but a world of somber, neutral color tones, of icy cold, and a gray and planeless wilderness called middle ground that lies between the surface and the bottom but out of sight of both.

Near the shore, the hostility of the surface barrier is apt to be diminished. A diver can orient himself with land, the world he knows. The veil has an edge, a place to peek around without too much exposure. The hostility and the mystery have a limit, and all is well. Far at sea, beyond sight of land, the ocean presents a different face. The veil stretches infinitely on every side. The mystery and hostility, especially on the dark surfaces of the temperate seas, are boundless. There is no reference point, no certainty, only a world of water drowning everything familiar, even the memory of land. The surface is a psychological barrier. "We were out of sight of land, with 1,500 fathoms of water under the keel, and the whale herd diving and spouting around the ship." When Cousteau wrote that in The Silent World, summing up the situation before a dive, the idea of the vast inimical wilderness of the open sea was very much with him.

In the broadest sense the hazards of deep-ocean diving fall into two categories, psychological and external; but to imply in the slightest that the former are any less real than the latter would be very wrong. Any dive has a rhythm, a sort of self-imposed pace or control that creates a sense of security and well-being. Breathing under water through a mouthpiece, or even with a full face mask, demands it. This rhythm is not something that one thinks about, but it is there, and when it is shattered the dive becomes chaotic and precipitates the external dangers in a disastrous rush.

Skin-diving without the use of any breathing apparatus has been practiced for centuries by pearl and sponge divers, mostly in tropical latitudes. But skin-diving with self-contained underwater breathing apparatus (scuba), properly called free diving, has within the last decade put so much mobility at a diver's disposal that those who were explorers by nature were bound to extend the frontiers. And so they have. They will dive far from land and will, if necessary, go deep (as much as 200 to 225 feet). All those who do it, and do it consistently and with security, know that this deep open-ocean free diving is a specialty, with its own peculiar dangers and tremendous allure. The promise of the unknown seems grand to them and draws them outward from the littoral, deep below the surface, always beyond the hazy perimeter of their vision. They are willing to pay the price of a well-calculated risk in the knowledge that they will reap the reward of discovery. Ignorance and curiosity sire all their explorations.

Jumping into the sea, breaking through the veil out of sight of land is an act one grows accustomed to after a while. It becomes exhilarating, an expression of a man's belief in his own indestructibility, a belief without which no one should undertake open-ocean diving. It signifies the clean, decisive beginning of a dive: the forethought and perhaps apprehension are left behind; the act is begun; imagination is disintegrated in a single splendid instant by the rush of reality. The passage between two worlds produces a unique feeling even in divers not much given to abstract thoughts. It has a brilliance and a purity, that leap far at sea.

As the explosion of tiny bubbles from the impact clears away, the first sweeping look around reveals one of the greatest differences between offshore and coastal diving: the characteristic clarity and luminosity of deep-ocean water. Sometimes the first look about catches a fast-running pelagic fish—tuna, jack or mackerel—silver, solid-bodied and wild; or a massive jellyfish, its streaming stingers pulsating in the bright-lit blue. Of course, the color difference between tropical and temperate water is tremendous, even far at sea. The oceans outside the tropical belts are darker in tone and less clear as a result of the greater concentrations of plankton, but they are not necessarily less beautiful. Within 30 or 40 feet of the surface, on a sunny day, the ocean water 15 or 20 miles off New England, eastern Long Island or California can be a breathtaking blue of a sort that hardly ever occurs in the warmer seas where the super-clarity (visibility sometimes reaches 150 feet) renders the color paler and less dramatic. But it is not color alone that gives open-ocean water a look so separate from coastal zones. It is a quality more definable in the feeling of hugeness and exposure it produces: the power of the liquid bond against the diver's skin, a free-flowing link with every other creature of that wall-less world.

In self-contained diving, one of the great limiting factors is time. All free divers carry a watch on deep dives. Their air supply is limited, and the deeper the dive the more critical the time factor becomes since the volume of air consumed with each breath increases in proportion with the depth. Because of this and also because the decompression tables (which define the limits of time and depth within which a diver is relatively safe from bends and indicate the maximum rate of ascent in the event that the limits have been exceeded) are calculated from the time of departure from the surface, a fast descent is really mandatory in deep free diving. Not that a slow descent is unsafe. In fact, it is safer in certain ways, but it is inefficient. Anyone who makes a deep dive presumably has a good reason for doing it and wants the maximum time at his objective depth. His air supply is a known quantity, and the decompression tables are intended to bring him up safely from deep down. If he wants to add safety factors to safety factors, he probably does not want the dive enough. If, on the other hand, for physiological reasons or because of poor technique, he is unable to "clear" his ears under rapidly increasing pressure, he is not qualified for deep diving.

Other than being able to equalize the pressure in the ears rapidly, deep free diving has no arbitrary prerequisites that do not apply to shallow diving. It seems too obvious to mention that the greater distance a diver puts between himself and the surface the less room he leaves for error. Like the skier who undertakes downhill racing, he is betting that whatever condition he finds ahead he will be able to handle. There comes a depth—and it varies too much with particular conditions to say exactly what it is—when you have stopped hedging your bets. It naturally follows that anyone who dives below 40 or 50 feet should be well beyond the point where he might feel compelled, due to general insecurity, to get to the surface immediately.

A descending line should be used as a safety measure in all offshore dives without exception. Its purpose is not, as might be supposed, for a diver to haul himself to the bottom. The slender filament serves rather as a guide which, if properly placed, will lead to the exact spot at which the diver wants to arrive on the sea floor. It performs another function that can be even more important: it marks the exact point where the diver submerged, so that in case the surface party monitoring his bubbles (which is absolutely the only way of knowing the location of a submerged free diver once he is out of sight) loses the trail—something that is very easy to do in weather that is anything less than ideally calm—the boat will know the general area in which to search. Anyone who has ever made a dive far at sea and surfaced only to see his tender, having lost the bubbles, searching aimlessly a half mile away, out of sight except when both he and the boat rise simultaneously on the crest of a wave, and has vainly yelled into the wind to attract attention as the waves slapped him in the teeth and hope leaked out of him will never again be likely to dive without placing a marker.

In terms of environmental change, there are probably very few experiences to compare in drama with a diver's rapid passage in temperate waters to a depth of 125 to 150 feet. Within a minute, the pressure on every square inch of his body increases fivefold; the temperature is likely to drop about 20° Fahrenheit; the light will fall from bright to twilight, and the dominant background colors will change from sunlit shades to neutral gloom. The planet he knew vanishes in a self-propelled, headlong plunge, a mere instant in duration.

Continue Story
1 2 3