Off the coast, a tall fin divided the sea into precise segments, signaling the path of the huge fish to the unbounded emptiness, to a few gulls and smaller fish that scattered. The fish appeared gray and white and moved with the precision and trajectory of an enormous bullet, a shot somehow fired in slow motion through the medium of the sea, moving with a purity and suppleness that were eerily beautiful. It is a principle of aircraft design that “a good plane is a plane that is nice to look at.” The great white swam on the surface of the deep like an airship given the lift of a summer sky.
Yet the shark's design was sophisticated beyond the flying machines of Langley or Wright or Curtiss, beyond human understanding in 1916, for it swam and hunted with the inborn perfection of thoughtlessness and genetic memory. It kept a steady keel that afternoon, and its fins wobbled slightly to one side or the other. Invisible lateral lines running down the length of its body recorded changing water pressure. They signaled its brain to adjust its fins, and the shark righted itself, adjusting to smooth cruising mode. As it moved, it read the earth's magnetic field—or the electricity generated by ocean currents moving about the field—like an electromagnetic compass. What use it made of this information is not known, but as it traveled undersea it rode swells of water and magnetism and electricity like a sailor courses the wind.
The shark could see colors. It could see several feet out of the water, could have seen people in a small boat looking down at it were a vessel circling over it, and now it noticed the salmon-yellow light in the sky changing and slightly darkening like the water. The fish had traveled some fifty miles along the coast in five days, and it was hungry. It is not known how often it came near shore during those five days, explored bays and harbors or straddled inlets, fed or failed to feed. But judging by its actions, its need to consume prey had become acute.
Nature had equipped the shark more splendidly than anything that lived to find prey. The shark possessed eight organs like complex interrelated systems for detection, stalking, and identification, systems that worked at all hours and in total darkness, supported by numerous backup systems in case of failure. Shark researcher Xavier Maniguet has compared the approach of a shark to that of a modern torpedo “whose various electronic means of reaching the target make ‘contact' almost inescapable.” As the shark detected the lower salinity and the mass of organic debris in the coastal waters that afternoon, its genetic memory was triggered, drawing it inexorably toward shore. Toward the coast town of Spring Lake.
As the shark neared Spring Lake, sound ratcheted curiosity up toward urgency. The noises were deep, low-frequency sounds, bass notes beyond human perception: The noise emitted by a speared fish, thrashing about, or by a human being splashing in the water. Or by a swimmer, more than a mile away.
Dowling and Hill were far into the Atlantic by then, miles apart and miles from shore, unaware they had entered the tracking range of a great white.
The shark now turned its head slowly, side to side, letting water wash into its nostrils, widely spaced below the mouth, and out again. The horizontal balancing movement of the head allowed the shark to test a wide corridor of smell. Its nose was “thinking,” and, turning its head reflexively in the direction of the nostril that received the strongest smell, the fish proceeded that way. Like a hunting dog, the shark's nasal cavity contained numerous folds to increase the surface area and number of olfactory sensors, but this nose was spectacularly more sensitive than a hunting dog's. Sharks can detect one part of blood in one million parts of water, yet the olfactory ability of the great white that day may have been far stronger. A shark is even capable of responding to concentrations of fish extract of one part in ten billion. To survive as a great white shark was extraordinarily difficult, so nature had supplied it extraordinary weapons.
A quarter mile distant, the great white could smell its prey. It had entered an “odor corridor,” a wide swath of scent in the rough shape of a crude Stone Age arrow, broad at the base and tapering to a point. The shark simply needed to follow the narrowing scent to its source.
The shark was in the water with them.
The thought would soon come to both Dowling and Hill. Yet it is perhaps not surprising that both men were unaware and also unafraid of the potential presence of a shark relatively near shore. The Edwardians were the first generation for whom the ocean had lost its terrors; the sea was a haven of leisure and entertainment, an illusion maintained a century later. “We've forgotten what the ocean is,” says ichthyologist George Burgess. “The ocean is a wilderness. We would never enter a forest wilderness without being aware of its dangers, its predators. Yet we think of the ocean as our giant backyard swimming pool.”
On the Atlantic Coast, sharks are constantly near shore, hunting and scavenging. Fly over Florida beaches in a helicopter or a small plane, Burgess says, and invariably you'll see them between the line of swimmers and the shore. The big shadows passing silently in four, six, nine feet of water, spying swimmers and moving on.
The great white in 1916 moved inexorably forward in its investigation of potential prey. Robert E. Dowling was four miles out to sea now, laboring to turn around, his strokes growing fatigued and sloppy, matching the profile of a fish in distress.
For its prey there would be no escape at this point. The shark's systems were designed to guarantee its death. Were the shark's eyes damaged or its hearing impaired, lateral lines beneath its skin would detect vibrations from any movement in the water—a frightened fish, a ship's propeller, a diver's flippers—and the shark would attempt to hunt down its quarry without hearing or seeing it. Given such faculties, Xavier Maniguet writes, “It is easier to understand how it is impossible for man to escape any determined investigation by a shark in the neighborhood.”
In the daylight hours of July 6, 1916, the shark's sonarlike capabilities were not necessary. At sixty feet, the shark could see a man in the water long before the man could see the shark. Using its ampulla of Lorenzini, a small organ under its nose, the shark could detect the man's faint electric field. At the last moment, when the great white unhinged its jaw and rolled its eye backward for protection, its ampulla of Lorenzini would locate the prey's beating heart.
Robert W. Dowling swam unaware of the crude yet brilliant appraisal of him as potential prey, the silent, unanswerable judgment by judge-jury-executioner. His movements were erratic, like a wounded fish's, yet the ocean was gentle and accommodating as he stroked four miles to shore and soon climbed out of the sea to handshakes and applause. Farther south, Leonard Hill returned too, from the direction of the shark—to land, to safety, and to kudos of his own.
Neither man had a clue, until later, that they had swum through the territory of a stalking, man-eating shark. Perhaps these long-distance swimmers were judged unpalatable, or too large to attack. It is not known why the shark bypassed either man or precisely why it kept hunting humans, only that it did.
When Dowling and Hill received the news later how close they had come to a man-eater, the endorphin euphoria of a long swim dissolved in chilled sweat. It is on record that both men immediately made new vacation plans. Separately, they vowed to abandon their careers as long-distance swimmers. Leonard Hill, the wholesale druggist from New York, swore he'd never swim beyond the lifelines again. Dowling, the flamboyant New York scion and celebrity swimmer, was more emphatic. Of the two men, he had swum closer to the path of the shark, quite near it, there seemed no doubt. He swore he would never swim in the ocean again.
“Never again,” he repeated. “At least, not here.”