Niagara: A History of the Falls (12 page)

BOOK: Niagara: A History of the Falls
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Unlike Ellet, who was all sizzle and froth and quick to take umbrage, Roebling was slow to arouse and tenacious in his ambitions. When he built a bridge he supervised every detail, left nothing to chance, prepared himself for every contingency. These Teutonic qualities were apparent when he decided to settle in the United States at the age of twenty-five. Long before he sailed he had carefully surveyed the prospect, state by state, so that he knew exactly where to put down his roots.

He came from the walled town of Mühlhausen in Thuringia, the son of an easy-going tobacconist and a ferociously ambitious mother who channelled all her energies into John, her fifth and youngest child. She entered him in the Royal Polytechnic Institute in Berlin where, according to family legend, he was the favourite disciple of the philosopher Hegel. But it was as an engineer and architect that he graduated, and it was as a farmer that he came to America. With several other countrymen he purchased seven thousand acres of land in Pennsylvania and formed a German-American village that would be called Saxonburg.

Seventeen years later, in 1848, when Ellet parted with the bridge companies, John Augustus Roebling was forty-two, a tall, lean engineer, his long, sombre face lined with deep furrows, his steel-blue eyes unblinking beneath a heavy brow, his beard giving him the appearance of a Biblical prophet.

He had long since given up farming to become the founder of the American wire rope industry. He had come to America while the canal still reigned, when the major communities were linked by a network of manmade waterways. Moonlighting in the winter months as a surveyor and dam builder, he had noticed deficiencies in the Kentucky hemp ropes used to haul canal boats across the Allegheny Mountains on the portage railroad that linked the eastern and western sections of the Pennsylvania Canal. The boats were hoisted into wheeled cradles and dragged by rope hawsers up the inclines, then dropped down on the far side to rejoin the waterway. Under the strain of this system, the thick hemp quickly wore out and had to be replaced.

Why not make the rope out of twisted wire? Roebling asked himself. It would be stronger, lighter, more durable. He fiddled with the idea, built a wire ropewalk on his farm, and eventually taught his fellow Germans his own technique of winding and weaving the strands. But when he approached the canal company, he met a wall of resistance.

Nobody had ever made wire rope in America. The Pennsylvania politicians who controlled the canal wanted no part of the idea; nor, understandably, did the hemp manufacturers. Roebling finally managed to wangle permission to try his scheme on one of the canal’s ten inclined railways. But he no sooner had his wire rope in place than his enemies chopped it in two.

The stubborn engineer went to the top – to the president of the state’s canal commission – and in a few bold sentences talked himself into a superintendent’s job. Soon all ten inclines were equipped with Roebling’s wire rope. “God is good!” said Roebling.

But the canal era was nearing its end, snuffed out by the new railroads. Undaunted, Roebling turned his inventive mind to another use for wire rope. He remembered that in his university days he had been impressed by a bridge suspended by chains over a small stream. Indeed, he had written a thesis on the subject. Now it occurred to him that the same principle could be used for a cross-river aqueduct but using wire rope, which was stronger than any chain.

He worked out his plans and calculations in the greatest detail and laid them before the canal company that was about to build an aqueduct across the Allegheny River at Pittsburgh. The idea was unprecedented. In Germany it would probably have been rejected. But Roebling, counting on New World daring, convinced the engineers that his scheme should be tried. If he failed, he faced ruin. But he did not fail, nor did he expect to. In fact, the success made his reputation.

If aqueduct pipes could be carried suspended over a broad river, Roebling pondered, why not a bridge? By 1846 he had built his first suspension bridge over the Monongahela River at Pittsburgh. It lasted thirty-five years.

By 1850, when after a two-year hiatus he was finally awarded the Niagara contract, Roebling had four more suspension aqueducts to his credit. He had also moved his wire rope business to Trenton, New Jersey. There he designed everything himself – not only the new plant but every piece of machinery he installed. His confidence in his abilities was absolute; he trusted no one else. Years went by before he could be persuaded to hire an assistant engineer or draughtsman.

Few others had his certitude. To the engineering profession he was a daring experimenter, possibly a madman. Five chain suspension bridges had already collapsed in Europe. Then in 1850, a wire suspension bridge twisted and crumpled under the tread of marching troops. Why was Roebling tempting disaster?

Robert Stephenson, son of the inventor of the locomotive and one of the best-known bridge builders in England, put no trust in the Roebling concept. He was convinced no suspension bridge could support a heavy train lumbering across its unsubstantial arch. Stephenson’s cumbersome and expensive bridges were constructed of tubular steel. “If your bridge succeeds,” he told Roebling, “then mine have been magnificent blunders.”

Roebling moved implacably forward. Using Ellet’s original span as a service bridge, he started construction in 1851. Again he oversaw every detail, planned every step, arranged for any contingency, left nothing to others. Since each Roebling bridge was different from every other, designed for the particular site and circumstance, he was like an artist who puts his own stamp or signature on canvas or sculpture.

Unlike the flamboyant Ellet, he worked without fanfare, often in the bitter cold, without a break. He rarely left the site. A town known, aptly, as Suspension Bridge was springing up on the American side, and from there, by mail, he ran his factory in Trenton, again following every detail himself – from the installation of new machinery to the collection of debts.

He worked as a man obsessed, oblivious to family and friends, shunning holidays, forgetting anniversaries. When the intricate work of cable spinning began in December 1853, he abandoned any thought of Christmas because he trusted no one but himself to oversee the job. “Mrs. Roebling wishes me to come home,” he had written to one of his staff. He concluded bluntly, “I cannot.”

When, on New Year’s Day, 1854, she bore him his fourth son, Roebling heard about it from Charles Swan, his factory superintendent, in a business letter, of all things. He seemed baffled and bewildered. “You say in your last, that
Mrs. Roebling & the child are pretty well
. This takes me by
surprise
, not having been informed at all … what do you mean? Please answer by return of mail. I myself was a little doubtful about the sufficiency of a 3-inch shaft – must try it now …” And thus, in spite of his puzzlement, he went on with the pressing business of the day.

He had no patience with the conventional thinking that a suspension bridge should be flexible. In these “loose fabrics swung up in the air for the very purposes of swinging” he foresaw future trouble. In Roebling’s view, the bridge itself should be as stiff as the wooden aqueducts he had previously designed.

Roebling’s two-tiered bridge resembled nothing so much as a gigantic iron girder, stretched across the gorge suspended by cables. It was 820 feet long, 24 feet wide, and 20 feet deep, an oblong metal box, slightly convex at the centre. The railway tracks and pedestrian walk ran along the upper level – the top of the box. Common traffic used the plank roadway at the bottom. In between was a massive nest of trusses, girders, and cables designed to keep the entire structure rigid. Roebling had, in effect, fashioned a single hollow beam as protection against cumulative undulations.

Roebling had made it impossible for his bridge to sway or twist in the wind. A heavy team of horses, Roebling declared, would cause a much greater jar or trembling than a train crossing at five miles an hour. The concept was Roebling’s own; it had never been tried before. This was the first time stiffening trusses had been used in bridge building, a radical innovation that would in the future become standard for all suspension bridges.

The span, when completed, weighed a thousand tons. It was hung from four ten-inch cables of wrought iron, each constructed of 3,640 wires, oiled, spliced, reeled, strung, adjusted, and finally wrapped by his own patented methods. As he wrote, with his usual confidence, the finished webs were not only pleasing but “their massive proportions are also well calculated to inspire confidence in their strength.” The tension composing each wire, he declared, “is so nearly uniform I feel justified in using the term perfect.”

In developing his theory of stiffening, Roebling was intuitive; the principles of aerodynamics were not known in 1854 and would not be for the best part of a century. No other engineer caught on to the fact that a high wind could cause undulations in the floor of a bridge that would build up until the bridge was destroyed.

Even Ellet failed to grasp this principle. The Niagara Suspension Bridge would survive for forty-two years. His own, over the Ohio River at Wheeling, lasted a mere five. Completed in 1849, it was the longest span in the world – more than a thousand feet – but remarkably light and narrow for its length. It lacked the strong mesh of stays and trusses that Roebling insisted upon, and that was its undoing.

In May 1854, a high wind struck Ellet’s bridge and collapsed it into a tangle of twisted girders. A reporter for the Wheeling
Intelligencer
had just walked off the structure when the catastrophe occurred. He turned to see it “heaving and dashing with tremendous force.” It “lunged like a ship in a storm,” the walkway rising almost to the height of the towers, then falling back, twisting and writhing until, in one last determined fling, half the flooring was nearly upside down.

“The great body of the flooring and the suspenders forming something like a basket between the towers, was swayed to and fro like the motion of a pendulum. Each vibration giving it increased momentum, the cables, which sustained the whole structure, were unable to resist a force operating on them in so many different directions, and were literally twisted and wrenched from their fastenings.” Shortly afterward, “down went the immense structure from its dizzy height to the stream below, with an appalling crash and roar.”

The engineering profession as a whole was baffled by this unexpected development. But not Roebling, who read the account and knew at once what had happened. His immediate reaction was to order additional stiffening for his bridge. From this point on engineers ignored Roebling’s principles at their peril. Almost ninety years later one group did. On November 7, 1940, the Wheeling disaster was duplicated, almost blow for blow, when a high wind struck the new Tacoma Narrows Bridge over Puget Sound in Washington State, causing it to shake to pieces.

In July 1854, a different kind of disaster struck Roebling’s bridge crew. A plague of cholera broke out, causing sixty deaths in the first week. Roebling didn’t stop his own work for a minute. Constantly exposed to the disease, he decided to use his willpower to fight it off, as he had once fought off seasickness. He paced his room all night, refusing to give in. “Keep off
fear”
he declared, “– this is the great secret. Whoever is afraid of cholera will be attacked, and no treatment can save him.…” Whether through willpower or plain happenstance, he survived. The epidemic ended in August.

The following January, Roebling’s bridge weathered a tremendous twelve-hour gale. “My bridge didn’t move a muscle,” he said proudly. Less than three months later, on March 8, 1855, with the structure almost complete, he put it to a series of tests using heavy locomotives. That day, a twenty-three-ton engine of the Great Western Railway crossed the span “without the least vibration.”

On March 18, when the bridge was opened to the public, a twenty-eight-ton engine carrying twenty double-loaded freight cars with a gross weight of 368 tons crossed the bridge, covering its entire length – the first train in history to cross a bridge suspended by wire cables. “No vibrations whatever,” Roebling noted jubilantly. “Less noise and movement than in a common truss bridge.”

The first passenger trains, jammed to the roof with people, crossed at the rate of twenty a day. “No one is afraid to cross,” Roebling exulted. “The passage of trains is a great sight, worth seeing it.” The Niagara Falls, New York,
Gazette
headlined a “Great Triumph of Art.” It was an even greater triumph of engineering. For this was the first railway suspension bridge in the world, constructed at a cost of only $400,000. As Roebling reported to the bridge companies, a European bridge would have cost four million “without serving a better purpose or insuring greater safety.” Stephenson’s heavy tubular bridges in Great Britain were now seen as obsolete. The suspension bridge belonged to the future.

Roebling’s Niagara bridge remained intact until, in 1897, it was finally retired to make way for a wider and stronger structure geared to the increase in rail traffic and the heavier rolling stock. But its wire cables were as sound as they had been when Roebling installed them more than forty-two years before. The same could not be said for the two bridges constructed by the other two men – Edward Serrell and Samuel Keefer – who had once been in the running with Ellet and Roebling to span the Niagara.

Serrell was given a contract to build a highway suspension bridge over the Niagara between Lewiston and Queenston. The 1,053-foot span was completed in 1851, damaged by a gale in 1855, and rescued by Roebling, who installed a system of guy ropes to protect it from the high winds. In the spring of 1864, after an ice jam had caused the workmen to loosen the guys, another gale destroyed Serrell’s bridge.

Three years later Keefer, an Ottawa engineer, was given the task of building the Clifton suspension bridge two miles closer to the Falls than the Roebling structure. This wooden suspension bridge – 1,268 feet long – was opened in 1869, widened and reconstructed with steel in 1887, and reopened in 1888. Seven months later, on January 9, 1889, a hurricane tore it from the cliffs and dumped it into the river, where it remains hidden beneath the waters to this day.

BOOK: Niagara: A History of the Falls
9.19Mb size Format: txt, pdf, ePub
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