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The Great Bridge Page 21
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James Buchanan Eads was an authentic American genius and one of the looming figures of the nineteenth century. Slim, leathery, highly opinionated, disliked by many, he had survived an extraordinary life on the Mississippi that had included a lucrative underwater salvage business, a financially disastrous attempt at glass manufacturing, and the building of a fleet of ironclad gunboats during the Civil War. These slow, squat, ugly warships, built before the Monitor or the Merrimac and nicknamed “the Turtles,” had played a decisive part in defeating the Confederates on the Mississippi, along with the rams built by Charles Ellet. Eads had not designed the ships himself, nor had he gone into battle with them as Ellet had with his rams, but he had organized everything, having timber cut in Minnesota and Michigan, iron armor rolled at St. Louis and Louisville, keeping four thousand men at work on a night-and-day basis, and financing much of the operation out of his own pocket. At the time Washington Roebling was distinguishing himself on Little Round Top, Eads’s gunboats were assisting Grant in the successful siege of Vicksburg.
In early 1870 Eads was approaching fifty. He was the sort of person who liked to play chess with two or three others at a time, and in a recent weight-lifting contest among some of his blacksmiths, he had come in second.
During his years in the salvage business Eads had worked with diving bells up and down the Mississippi and was said to know more than any man alive about the river’s treacherous currents and the character of its bottom. This had been an important factor when he presented St. Louis and New York financial backers with his radical proposal for a bridge over the Mississippi. But it was his unbridled self-confidence and his reputation as a man who could get things done that mattered most in the end. He managed to convince men who had worked with the country’s foremost engineers that he, James B. Eads, was the one man fit to bridge the Mississippi at St. Louis, that the bridge he wanted to build was the only answer, and this despite the very well-known facts that he had had no formal training as an engineer and that he had never once built a bridge before. Both Charles Ellet and John A. Roebling had prepared plans for suspension bridges at St. Louis back in the 1850’s. Later, the year before he died, Roebling had done an entirely new set of plans, combining both suspension cables and parabolic arches. But Ellet’s and Roebling’s ideas had been turned down. (The St. Louis people were fools, John Roebling wrote to his son.) Now Eads and his bridge were the talk of St. Louis.
The great need was for a bridge to carry a railroad and highway over the river without interfering with steamboat traffic. The Mississippi at St. Louis is about the same width as the East River. Instead of a heavy iron truss, the customary thing then for railroad crossings, or a suspension bridge, Eads had conceived a mammoth arched bridge, with arches of steel set on stone piers. He intended to span the river with just three of his steel arches, the biggest of which, the center span, would be longer than any arch of the time by several hundred feet. To avoid interfering with river traffic during construction, his assistant, an engineer named Henry Flad, had devised a cantilever system nobody had tried before. The halves of each arch would be built out toward one another from their respective stone foundations, like great jaws slowly closing over the river, which was the conventional way, except that here the temporary supports needed (until the jaws joined) would be supplied from above. The usual practice was to prop such arches up from below with temporary timber “falsework” that could be torn out once the bridge was finished. But since this would be impossible, obviously, if the river was to be kept clear, Eads would hang the arches from overhead cables attached to temporary wooden towers built above each of his stone piers.
So the design of the bridge, the material he intended to build it with, the way he planned to build it, just about everything about the bridge, was unorthodox and untried. And when he had first proposed it, Andrew Carnegie had decided that somebody who knew about things mechanical, as he said, had better look over the plans.
Carnegie’s interest in the bridge was twofold. He had been approached by Eads’s St. Louis backers to see if he might be interested in selling some of their bridge bonds. Also, it was a few years before this that he had organized his Keystone Bridge Company, one of the first to specialize in manufacturing iron railroad bridges. Carnegie enjoyed talking about his love of bridges. Like Thomas Pope and John Roebling he saw them, he said, as testimonials to the national spirit and professed great personal satisfaction in the part he played in building them.
The Keystone company was now being invited to come in on the St. Louis job as consultants and to handle the superstructure. So Carnegie, quite sensibly, asked for an opinion on the bridge from Keystone’s chief engineer and president, J. H. Linville, whom Carnegie described with customary enthusiasm as “the one man in the United States who knew the subject best.” This was an overstatement, but Linville was certainly among the finest men in engineering. He had been bridge engineer for the Pennsylvania Railroad before Carnegie hired him and the huge iron truss he had built over the Ohio at Steubenville in 1864 was considered the outstanding structure of its kind.
Linville asked that a set of Eads’s plans be sent to him. He examined them carefully, then, a little like the paleontologists who had been asked to give an opinion on the Cardiff Giant, he solemnly declared the subject preposterous. “The bridge if built upon these plans will not stand up; it will not carry its own weight,” he told Carnegie in private, and presently, in a formal statement, he called the bridge “entirely unsafe and impracticable” and said any association with it on his own part would imperil his reputation and was therefore out of the question.
Linville was quite wrong and Carnegie, who knew nothing about engineering, urged Linville to lead Eads “into the straight path.” Eads, however, was not about to be dissuaded or to have any outsider, regardless of reputation or connections, begin doctoring his bridge. In the end he would convince even Linville that he knew what he was doing. The Keystone company went to work on the bridge; Carnegie went off to London to sell a block of bonds to the American financier Junius Morgan, father of J. P. Morgan; and by the summer of 1867 Eads was confidently proceeding with the preparatory work for the first abutment beside the St. Louis waterfront. In neighboring saloons it was said that the bridge would take seven million dollars to build—and seven million years.
As things turned out the final cost would come to something near ten million, and seven years would go by before the job was completed. Once in use the bridge would be acclaimed by everyone, and by engineers especially. As one engineering historian would write, the bridge was “an achievement out of all proportion to its size,” something Washington Roebling thoroughly appreciated at the time Eads came over to visit the Webb & Bell yards.
Like every bridge engineer and every railroad official in the country, Roebling was keenly interested in the St. Louis bridge, but since Eads, along with everything else in his radical scheme, also planned to sink his piers by means of pneumatic caissons, Roebling perhaps more than anyone appreciated the full daring of the man and the tremendous importance of what he was attempting, not just to his own work at Brooklyn but to the whole future of bridge engineering.
When he first envisioned his bridge, Eads had originally planned to use coffer-dams to sink the two midriver stone piers upon which his great steel arches were to rest. But in April of 1869, he had returned from a trip to Europe, convinced he had a better answer. He had seen the French engineer Moreaux use a pneumatic caisson to sink piers for a bridge over the Allier River at Vichy and he came home full of faith in the technique and sure he could make it work at St. Louis, even though the Mississippi, as he knew better than anyone, was not the gentle Allier.
So through that summer of 1869 Eads and Roebling had been devising their own separate plans for the foundations of the two biggest, most important bridges of the age, each man working quite independently and with only his own judgment to go by. Eads, however, had his caisson in the water by mid-October, before the contract with Webb & B
ell had even been signed, and by the time Eads arrived in Brooklyn, his caisson was already well on its way into the sandy bed of the Missssippi.
Of the two, Roebling was unquestionably the better educated on the development of caissons in Europe and the various ways they had been used. Eads had happened onto the technique almost by chance and took about the least time possible to educate himself. Roebling’s father had incorporated caissons in his plans from the start, knew much on the subject, and Roebling himself had taken great pains in his studies, spending close to a year in Europe for that specific purpose. Furthermore, unlike Eads, Roebling was a trained, experienced bridge engineer and was fluent in both French and German. Eads, who spoke only English, had had a difficult time conversing with some of the European engineers he met.
Still and all, Roebling doubtless appreciated that Eads was a man with a most uncommon gift for solving problems, a man of extraordinary originality and determination, a man, in fact, very much like his own father. Roebling also knew that what Eads was up against at St. Louis was far closer to his own situation in Brooklyn than anything the Europeans or McAlpine or anyone else had ever had to cope with. And most important, Eads, unlike Roebling, now had some working experience with caissons.
The caisson Eads had in operation was only about one-third the size of what Roebling was having built in Brooklyn, still it was bigger than any used by the Europeans. More significantly, by January 1870, the Eads caisson was already as deep as Roebling expected he would have to go on the Brooklyn side, and it was still descending steadily through Mississippi sand and mud that offered almost no resistance. By the end of January the trouble had begun.
From the very first Eads’s men had noticed certain peculiarities about working in the heavy atmosphere of the caisson. The most manly voices had a thin girlish sound, for example. It was impossible to whistle or to blow out a candle, as the men gladly demonstrated for the many visitors Eads liked to bring down. Some of the men mentioned a notable increase in their appetites. Others talked of trouble breathing or of a painful ringing in the ears. But by the time they were down forty feet there had been several clear cases of the mysterious sickness, a subject Eads and Roebling had both heard something about in Europe.
As early as 1664 an English doctor named Henshaw had published an essay proposing, ironically enough, that compressed air be used as a method of treating a variety of common disorders. In France and Germany, institutions sprang up offering the latest facilities for just such atmospheric treatment. Compressed-air “baths” were claimed to work miraculous cures and became something of a fashion, and particularly for curing indigestion. But the pressure in such baths was never much greater than normal.
The first civil engineer to work with compressed air of any substantial magnitude, however, was a Frenchman named Triger, who in 1839, or thirty years before Eads and Roebling built their caissons, used compressed air inside an iron tube to hold back water while sinking a mine shaft through quicksand. The technique had worked quite successfully, but before the job was completed, Triger observed a number of unexplainable reactions among his men and put down in his notes what are thought to be the earliest recorded cases of caisson disease, or “the bends.” Two of his men, Triger wrote, had been hit quite mysteriously by sudden sharp pains in the arms and knees about half an hour after coming out into the open air.
Later in France there would be more serious cases. Men would be seized at home, long after coming out of compression. Sometimes the pain was accompanied by chills and vomiting. Other symptoms were recorded: a great dullness of mind, an incoherence of speech or stammering, nosebleeds, a distressing itching of the skin, tottering gait, an increased flow of urine, even pain in the teeth. One supposedly scientific study noted that Hungarians and French suffered least, while Italians, Germans, and Slavonians were said to have had by far the worst time. It was also known for a fact that one or two men had died of the experience.
The first signs among Eads’s men had been occasional muscular paralysis in the legs. But there was no pain connected with it, the men said, and the sensation passed off in a day or so. But as the caisson went deeper more and more of them began having trouble. In some cases now the arms were affected, as well as the bowels and sphincter muscles. Men complained of severely painful joints and sudden, excruciating stomach cramps. Still, nine out of ten of those affected felt no pain whatever, they said, and so long as the phenomenon remained painless, it would not be taken very seriously. Indeed, according to one account, “A workman walking about with difficult step and a slight stoop was at first regarded as a fit object for jokes, and cases of paralysis and cramp soon became known popularly by the name of ‘Grecian Bend.’”
To ward off trouble the men rubbed themselves with an “Abolition Oil” that was said to work like a charm. Some of them began wearing bands of zinc and silver about their wrists, arms, and ankles, and such were the claims of success that Eads decided to thus outfit every man on the force at the company’s expense, only now the protective armor, as the men called it, was worn about the waist as well, and even under the soles of the feet. Still instances of the unaccountable malady continued to increase.
When one of his foremen got sick, Eads decided to shorten the shifts inside the caisson. The men would stay down for four hours only, then rest for eight hours before going back for another four. The caisson was at forty-two feet by then. By February 5, when it was at sixty-five feet, Eads again altered the schedule, to three two-hour shifts, with rests of two hours in between, none of which was very popular with the men, since with every change of the shift they had to make a long climb out of the caisson, up a spiral stairway. For those who felt no adverse reaction from the compressed air, the new routine was just one more big inconvenience, while for those who did, the climb was only added torture. As the official history of the bridge states dryly, “The fatigue of ascent added not a little to the distress and prostration of those affected with cramp.” At seventy feet, on February 15, with the air pressure in the chamber at thirty-two pounds per square inch, or more than double that of normal atmospheric pressure, one man was in such pain that he was sent to the hospital.
Severe cases grew a lot more common after that. One man became unconscious and did not speak for three hours. Nobody considered the thing a joke any longer. But even so, as Eads would tell visitors, many of his men, the majority in fact, had been affected in no way at all. He had taken hundreds of visitors down into the caisson, even “delicate ladies,” he said, without any of them experiencing ill effects. There was no doctor who could explain it satisfactorily for him. Some doctors said a slower transition from the abnormal to natural pressure would prove less injurious; others claimed the contrary, that the trouble came from passing too rapidly from natural into compressed air. But Eads argued that neither could be correct since none of his air-lock attendants had been hit. It was the amount of time spent under compression that caused the trouble, he maintained, plus the general physical condition of the individual.
He pointed out that most of the men who had been struck down were new hands, unaccustomed to the work, that they had been thinly clothed and poorly fed to begin with, or, in some cases, alcoholic. So as the caisson continued its descent, Eads ordered that only men in prime physical shape be hired for the work.
Then on Saturday, March 19, which happened to be the same morning the Brooklyn caisson was launched, Eads reported the first death. The man’s name was James Riley. He had worked the first shift, just two hours in the chamber, came up feeling fine so far as anyone knew, then fifteen minutes later gasped for breath and fell over on his face. He was the first American to die of the mysterious disease. But at least fifteen more would die at St. Louis before Eads finished his bridge, and more would be crippled for life.
About three thousand people turned out to watch the launching of the Brooklyn caisson. The Kings County Democrats, to no one’s surprise, took the opportunity to make it a day of speeches and band music. People had tr
ouble thinking of a suitable way to describe the main attraction, but most eventually concurred that it looked “more like a huge war leviathan or battery for harbor defense than any other thing.” And as the Eagle observed, a very large number of them had turned out chiefly because they doubted it could ever be launched.
The top, or deck, of the caisson was strewed with tackle and various odd-looking pieces of machinery. A number of lines were connected to a steamboat standing by in case of trouble going down the ways, and at the rear of each way, heavy wooden rams had been rigged, to be worked simultaneously, to get the huge structure started. Inside, a temporary airtight compartment had been built on the forward wall to buoy up that side as it hit the water, and a full complement of crabs, winches, and 150 wheelbarrows had been stowed away, battened down with strips of wood.
The launch took place at ten thirty and was in every respect a great success. As soon as the last block was split out, the giant mass began to move. It went down straight and even, with no need of assistance. It struck the river with just enough speed to overcome the resistance of the water and the air chamber worked to perfection, keeping the front side from sinking. The deck never even got wet.
A great roar went up from the crowd. An air pump on the deck was at once set in motion and in a few hours the water was all out of the work chambers, thus proving to Roebling’s satisfaction that the thing was airtight. Later on the air inside was allowed to escape and the top of the caisson settled to within seventeen inches of the water, which, Roebling noted with pleasure, happened to agree exactly with his previous calculations.