Thunderstruck

GUNFIRE

EACH MOMENT MATTERED. MARCONI shrank the size of his coherer until the space containing the filings was little more than a slit between the two silver plugs. He tried heating the glass tube just before he sealed it so that once the air within cooled and contracted to room temperature it would create a partial vacuum. This by itself caused a marked improvement in the coherer’s sensitivity.

A persistent irritant was the need to tap the coherer to return it to a state where it once again could respond to passing waves. No telegraph system could survive such a laborious and imprecise procedure.

Marconi devised a clapper like that from a bell and inserted it into the receiving circuit. “Every time I sent a train of electric waves,” Marconi wrote, “the clapper touched the tube and so restored the detector at once to its pristine state of sensibility.”

He took his experiments outdoors. He managed to send the Morse letter S, three dots, to a receiver on the lawn in front of the villa. With additional tinkering and tweaking to improve the efficiency of his circuits, he increased his range to several hundred yards. He continued trying new adjustments but could send no farther.

One day, by chance or intuition, Marconi elevated one of the wires of his transmitter on a tall pole, thus creating an antenna longer than anything he previously had constructed. No theory existed that even hinted such a move might be useful. It was simply something he had not yet done and that was therefore worth trying. As it happens, he had stumbled on a means of dramatically increasing the wavelength of the signals he was sending, thus boosting their ability to travel long distances and sweep around obstacles.

“That was when I first saw a great new way open before me,” Marconi said later. “Not a triumph. Triumph was far distant. But I understood in that moment that I was on a good road. My invention had taken life. I had made an important discovery.”

It was a “practician’s” discovery. He had so little grasp of the underlying physics that later he would contend that the waves he now harnessed were not Hertzian waves at all but something different and previously unidentified.

Enlisting the help of his older brother, Alfonso, and some of the estate’s workers, he experimented now with different heights for his antennas and different configurations. He grounded each by embedding a copper plate in the earth. At the top he attached a cube or cylinder of tin. He put Alfonso in charge of the receiver and had him carry it into the fields in front of the house.

He began to see a pattern. Each increase in the height of his antenna seemed to bring with it an increase in distance that was proportionately far greater. A six-foot antenna allowed him to send a signal sixty feet. With a twelve-foot antenna, he sent it three hundred feet. This relationship seemed to have the force of physical law, though at this point even he could not have imagined the extremes to which he would go to test it.

Eventually Marconi sent Alfonso so far out, he had to equip him with a tall pole topped with a handkerchief, which Alfonso waved upon receipt of a signal.

The gain in distance was encouraging. “But,” Marconi said, “I knew my invention would have no importance unless it could make communication possible across natural obstacles like hills and mountains.”

Now it was September 1895, and the moment had come for the most important test thus far.

HE SAT AT THE WINDOW of his attic laboratory and watched as his brother and two workers, a farmer named Mignani and a carpenter named Vornelli, set off across the sun-blasted field in front of the house. The carpenter and the farmer carried a receiver and a tall antenna. Alfonso carried a shotgun.

The plan called for the men to climb a distant hill, the Celestine Hill, and continue down the opposite flank until completely out of sight of the house, at which point Marconi was to transmit a signal. The distance was greater than anything he had yet attempted—about fifteen hundred yards—but far more important was the fact that it would be his first try at sending a signal to a receiver out of sight and thus beyond the reach of any existing optical means of communication. If Alfonso received the signal, he was to fire his shotgun.

The attic was hot, as always. Bees snapped past at high velocity and confettied the banks of flowers below. In a nearby grove silver-gray trees stood stippled with olives.

Slowly the figures in the field shrank with distance and began climbing the Celestine Hill. They continued walking and eventually disappeared over its brow, into a haze of gold.

The house was silent, the air hot and still. Marconi pressed the key on his transmitter.

An instant later a gunshot echoed through the sun-blazed air.

At that moment the world changed, though a good deal of time and turmoil would have to pass before anyone was able to appreciate the true meaning of what just had occurred.