In modern times, Bernoulli's Law explains such diverse phenomena as why a baseball curves, why a sailboat can sail into the wind, and why an airplane wing lifts the aircraft. But then, as now, most people did not really understand these events in terms of physics: most jet-age travelers would probably be surprised to learn that a jet flies because it is literally sucked upward into the air by a partial vacuum over the wings' upper surface, and the sole purpose of the engines is to propel the wings forward fast enough to create a stream of passing air that produces this necessary vacuum.
Futhermore, a physicist would dispute even this explanation as not really correct, and would insist that a rigorous explanation of events is even further from the public's "common sense" idea about these phenomena.
In the face of this complexity, one can readily understand Pierces own confusion, and the erroneous conclusion. he drew. Apparently he believed that the airstream around the moving carriage, as described by "Baroni," would act to suck him down to the carriage roof, and thus help him to maintain his footing as he moved from car to car.
The truth is that Bernoulli's Law would not operate in any way on his body. He would simply be a man exposed to a fifty-mile-an-hour blast of rushing air, which could blow him off the train at any moment, and it was absurd for him to attempt what he did at all.
Nor was this the extent of his misinformation. The very fact that high-speed travel was so new left Pierce, along with his contemporaries, with very little sense of the consequences of being thrown from a fast-moving vehicle.
Pierce had seen Spring Heel Jack dead after being thrown from the train. But he had regarded this with no sense of inevitability, as the outcome of some inexorable physical laws. At this time, There was only a vague notion that to be thrown from a speeding train was hazardous, and somewhat more hazardous if the train was moving rapidly. But the nature of the hazard was thought to lie in the precise manner of a person's fall: a lucky man could pick himself up with a few scrapes, while an unlucky man would break his neck on impact. In short, a fall from a train was regarded pretty much like a fall from a horse: some were worse than others, and that was that.
Indeed, during the early history of railroads, there had been a sort of daredevil's sport called "carriage-hopping," favored by the kind of young men who later scaled public buildings and engaged in other madcap escapades. University students were particularly prone to these amusements.
Carriage-hopping consisted of leaping from a moving railway carriage to the ground. Although government officials condemned the practice and railway officials flatly forbade it, carriage-hopping enjoyed a brief vogue from 1830 to 1835. Most hoppers suffered nothing more serious than a few bruises, or at worst a broken bone. The fad eventually lost popularity, but the memory of it bolstered the public belief that a fall from a train was not necessarily lethal."
In fact, during the 1830s, most trains averaged twenty-five miles an hour. But by 1850, when the speed of trains had doubled, the consequences of a fall were quite different, and out of all proportion to a fall at slower speeds. Yet this was not understood, as Pierce's testimony indicates.
The prosecutor asked: "Did you take any manner of precaution against the danger of a fall?"
"I did," Pierce said, "and they caused me no little discomfort. Beneath my ordinary external garb, I wore two pairs of heavy cotton undergarments, which had the effect of making me unpleasantly heated, yet I felt these protective measures necessary."
Thus, wholly unprepared and entirely miscalculating the effects of the physical principals involved, Edward Pierce slung a coil of rope over his shoulder, opened the compartment door, and clambered up onto the roof of the moving carriage. His only true protection--- and the source of his audacity--- lay in his complete misunderstanding of the danger he faced.
The wind struck him like an enormous fist, screaming about his ears, stinging his eyes, filling his mouth and tugging at his cheeks, burning his skin. He had not removed his long frock coat, and the garment now flapped about him, whipping his legs "so fiercely that it was painful."
For a few moments, he was totally disoriented by the unexpected fury of the shrieking air that passed him; he crouched, clutching the wooden surface of the coach, and paused to get his bearings. He found he could hardly look forward at all, because of the streaking particles of soot blown back from the engine. Indeed, he was rapidly covered with fine black film on his hands and face and clothing. Beneath him, the coach rocked and jolted in an alarming and unpredictable fashion.
He very nearly abandoned his intent in those first moments, but after the initial shock had passed he determined to go forward with his plan. Crawling on his hands and knees, he moved backward to the end of the coach, and paused at the space over the coupling that separated his carriage from the next. This was a gap of some five feet. Some moments passed before he gathered the nerve to jump to the next car, but he did so successfully.
From there he crawled painfully down the length of the car. His frock coat was blown forward, covering his face and shoulders and flapping around his eyes. After some moments of struggle with the garment, he shucked it off and saw it sail away, spun twisting in the air, and eventually fall by the roadside. The whirling coat looked enough like a human form to give him pause; it seemed a kind of warning of the fate that awaited him if he made the slightest error.
Freed of the coat, he was able to make more rapid progress down the second-class coaches; he jumped from one to the next with increasing assurance, and eventually reached the luggage van after a period of time he could not estimate. It seemed an eternity, but he later concluded it had not required more than five or ten minutes.