National Geographic : 1952 Oct
Fish Men Explore a New World Undersea themselves by sucking in water and expelling it behind them, and on occasion we saw them release their notorious "ink." This murky cloud is neither camouflage nor a venomous screen, though other recent investi gators say the "ink" is slightly caustic and therefore distasteful to fish. However, too small actually to hide the octopus, the cloud may well be meant to represent a false octo pus, a vague sort of decoy designed to fool weak-eyed pursuers. A diver can easily outswim an octopus, which usually flutters quickly to the bottom, spreads out, and pretends it isn't there. Prodded, the octopus will make one despairing leap and then become as docile as a tabby cat. We saw all this in the twilight zone of the sea, where the spectrum's red waves were filtered out, where red coral appeared dark blue, carmine gorgonians seemed violet, and blood flowed emerald green. We knew it would take many months before the biological specimens collected in this stratum would undergo final analysis and before scientists could or would launch their first tentative generalizations on the life we had explored. But one thing we had for sure: photographs. Men have looked into the sea before and taken pictures through windowed boxes, through the portholes of bathyspheres,* and, clad in cumbrous helmets, through the tropic shallows. No one to our knowledge, however, had ever swum down to great depths and with artificial light of great intensity caught on film the actual colors of the fish's kingdom. Treasure from a Roman Argosy My own experiments had begun four years before. Like most scientists and divers, I had assumed that pigmentation 50 or 100 feet below the surface was pallid and uninterest ing. Then, in the summer of 1948, Tailliez, Dumas, and I had dived by Aqualung down to the wreck of a Roman vessel sunk in 130 feet of water off Tunisia. It had been built by Sulla to transport loot from the sacking of Athens. From its deck I brought up three marble columns and two Ionic capitals, part of a Greek temple which apparently had struck the fancy of the emperor. Though daylight had appeared to illumi nate these fragments well enough on the sea bottom, where they seemed a dull gray and brown, I was astounded to find at the surface that their encrustations of algae actually glowed with violent reds and oranges. Determined to defeat this capacity of deep water to screen out the more brilliant colors, I started at once to improvise means of bring ing adequate artificial light below. Attaching a powerful lamp to a surface connection, I took it down to the twilight zone, 150 feet below the surface, and there, on 35-mm. Agfa color Cine film, took the first pictures of the depths in their true colors. Since we wished to check the behavior of color emulsions and flash-bulb lights under the sea, we were forced to try many combina tions of both daylight and interior flash film as well as blue and natural bulbs. We diversi fied these permutations even more by dipping the bulbs in tinted varnishes of several colors. The cameras we used were not unusual in themselves, but their housing was. We built into them enough air ballast to give them a positive buoyancy of one pound, which both assured their easy handling below and their ability to float if we had to drop them. Even the Cameras Wore Aqualungs We did more. We permitted our cameras, like ourselves, to "breathe" at any depth. To each was attached a miniature Aqualung which fed it compressed air in proportion to the increase in pressure of the sea around it (page 440). The diver simply opens a valve on the camera at the surface, allowing air to enter the regulator. Thereafter, as he swims down ward with the camera, its regulator automati cally adjusts the intake of compressed air to compensate for each additional foot of depth. A further refinement we devised was to mount our Rolleiflex on a shaft with two pistol grips. The diver trains his camera on the subject like a charging submachine gunner. By revolving one grip, he can change the focus; the other alters the aperture. Our principal problem, of course, was always one of light. The most powerful flash bulbs we could obtain gave an illumination of some 5,000,000 lumens-about 400,000 candle power. On land, such a bulb exploded at night will make possible a color shot 50 feet away in ^2, of a second. In the twilight sea, dense with its quintillions of microscopic organisms and suspended minerals, a similar flash will light up only a 5-foot radius. And to set off eight bulbs of this power at once will illuminate, for color purposes, only an additional seven feet. When we took our underwater photographs on the Calypso expedition, we usually em ployed four Aqualung divers-one to man the camera, two to carry the lights, and one to act as subject. It was an eerie studio in which we operated. Down from the brilliant surface we would glide, past the cliff dwellings of a thousand fish, into the dusk of 150 or 175 feet below. * See, by William Beebe, in the NATIONAL GEO GRAPHIC MAGAZINE: "Half Mile Down," December, 1934; "Wonderer Under Sea," December, 1932; "Depths of the Sea," January. 1932; and "Round Trip to Davy Jones's Locker," June, 1931.