With the establishment of registration laws and the growing proliferation of engineering schools, entry into the profession via the self-taught route of an Eads, or even the semiformal educational route of a Lindenthal, became less and less common. Though state licensure regulations included grandfather clauses so established practitioners were not excluded no matter what their route to their practice, and allowed for responsible experience as a substitute for formal education, earning an engineering degree was increasingly the way to become an engineer.
As president of a national group, Steinman spoke and wrote frequently on matters relating to the profession, including engineering education. Whereas so many in his profession less than a century earlier had little if any formal education, Steinman expected the engineer of the twentieth century to be a lettered individual. Then, when identifying himself to strangers as an engineer, he would not hear “an involuntary exclamation,” as Herbert Hoover once did from a woman he had met while traveling, followed by her admission, “Why, I thought you were a gentleman!” Hence, among the ways Steinman saw to advance the status of the profession was the manner in which engineers were educated. This had changed to a considerable degree since the nineteenth century, but he saw reasons for it to change further still:
The four-year course may have been adequate two generations ago, but the increasing content of essential engineering knowledge and the growing recognition of the desirability of a background of liberal and cultural studies for a professional man have altered the picture. Those of us who took a complete college course before entering an engineering school have never regretted it.… Personally, I favor a pre-engineering college course of two years, ultimately of four. This is in line with the best standards achieved in other professions.
Although Steinman might have changed “men” to “men and women” if he were writing today, he would have to change little else, for the issue of what form an engineering education should take, and whether it should follow a general college degree, is still a matter of some discussion. A strong argument can also be made that engineering, which is “essentially a mode of thought based on a mastery of the laws of nature,” should be a component of all liberal education in an age that must deal with problems not only of bridging ever-wider chasms, both literally and figuratively, but also of undoing some of the inherited neglect and environmental legacies of earlier times.
In addition to advocating the liberal education and registration of engineers, Steinman pushed for use of the professional title “Engineer” or “Engr.” with personal names, which he likened to physicians’ use of “Dr.” Adopting the practice for himself, Steinman began to sign his letters “Engr. D. B. Steinman.” On this issue, however, not even Engineering News-Record was in his corner. In an editorial commenting on Steinman’s introduction of the proposal at the first annual meeting of his National Society of Professional Engineers, the magazine retorted: “Engineers above all are supposed to be logical; do they propose to follow the present plan to its logical conclusion with Physician Jones, Dentist Smith, Chiropractor Brown—or Barber Cavello, for that matter, for barbers too are licensed in the interest of public safety?”
Among the letters to the editor on the subject was one from Ing. Robert B. Brooks, Jr., who pointed out that the “Mexican engineer is a titled individual.” Indeed, in many Spanish-speaking countries, the earned title “Ingeniero” is a mark of distinction, as is the title “Ingenieur” in Germany. But such traditions were not easily introduced in America, “where titles have been looked upon with disfavor.” No matter the inconsistency of Engineering News-Record in forgetting that the young country did confer the titles of doctor, senator, general, captain, professor, and the like; the time was not propitious for Steinman to be suggesting the adoption of the title of engineer. Though his commitment to the issue never fully disappeared, it seems to have flagged a bit after he completed his two terms as president of the National Society of Professional Engineers. Among the things that competed for his time and attention were the new opportunities that had arisen for engineers generally to undertake bridge projects following such eminently successful and prominent models as the George Washington Bridge, in which the structure was paid for by the tolls levied on the traffic using it.
5
All the great bridge designers seemed to want to hold the record for the longest span, but there were only so many locations that needed or could justify a bridge of record size. Among the last of the great unbridged crossings in the United States that remained unspoken for in the mid-1930s was the entrance to New York Harbor known as the Narrows. Ammann was only one engineer working clandestinely at the time on plans for a bridge at that location. Steinman also saw the crossing not only as the opportunity to regain the span record for the East Coast, but also as the opportunity of a lifetime for an engineer who wished to be memorialized in his work. Though perhaps not quite so obsessive about what Steinman would call his “Liberty Bridge” as Lindenthal was with his North River Bridge, Steinman nevertheless worked on and off on the design for twenty-five years, possibly having an idea for the structure as early as 1926. It was planned to have a main span of 4,620 feet, “a thousand feet longer than the George Washington span” and over four hundred greater than the Golden Gate. Steinman would also point out that it would have a clearance of 235 feet above high water, “100 feet higher than the East River Bridge,” of his great hero Roebling, and towers eight hundred feet high, “higher than the Woolworth Building.”
David Steinman’s unrealized Liberty Bridge (photo credit 6.11)
After the death of Holton Robinson, Steinman practiced under his own name for fifteen years. The cover of a brochure issued by D. B. Steinman in the late 1940s was dominated by a sketch of Liberty Bridge. A smaller reproduction of this same sketch had appeared without identification or comment on the inside title page of a Robinson & Steinman brochure dating from the early 1930s, but now a description of the cover declared that Steinman’s dream would be “the world’s greatest engineering achievement. Furthermore, spanning the gateway to America, it will be a symbol of our free, vital civilization, a portal of hope and courage—an inspiring symbol of the spirit of America.” These postwar words may have been intended to rouse support for his dream bridge, and they may indeed have done that among his friends and associates, but Steinman apparently did not have the ear of Robert Moses, the person who, perhaps more than any other single individual, controlled whether a bridge would be built across the Narrows and, if it would, who would build it. Ironically, Steinman, the supreme politician of his profession, seems to have been much more naïve in the local politics of bridge building than Ammann or Strauss in their quests to erect a great bridge in a great municipality. Nevertheless, as late as 1948, in an interview that appeared in The New York Times, Steinman said, “I expect Liberty Bridge to be built and hope to be identified with it.” After that achievement, he would be ready to retire, he allowed, but an aging engineer had to do more than hope to win the competition for a great bridge.
Steinman continued to promote his Liberty Bridge, and himself, in his own way. The back cover of the same brochure that carried a sketch of the span contained a photograph of “the hands of Dr. Steinman at work on plans for the great span over the Narrows,” taken by the photographer Frank H. Bauer for a book of studies of “the hands of outstanding representatives of the various arts and professions.”
To accompany his hands using dividers and scale, Steinman took a quote from John Ruskin about building not for “present delight” but “forever” with stones that “will be held sacred because our hands have touched them,” by descendants who will say, “See, this our fathers did for us.” Steinman, who never showed any such admiration for his own father, evidently thought so much of the portrait of his hands that it formed the larger-than-life focus, surrounded by images of many of his already realized bridges, in a mural in an engineering-faculty lounge that he would donate to the University of Florida. Before he did that,
however, Steinman thought there might be an opportunity for greater exposure of his engineer’s hands immortalized with dividers and scale over drawings of his dream bridge. In fact, he thought the image would form the perfect basis for the design of a postage stamp that was to be issued to commemorate the centennial of the American Society of Civil Engineers, in 1952. As late as 1957, a biographical sketch of Steinman described such a stamp as having been issued, but the stamp that was actually released in 1952 showed not an engineer’s hands but two bridges—a covered wooden bridge and a steel suspension bridge, which represented the century of engineering progress. Steinman must have been greatly disappointed that his stamp design was displaced in the final decision, but he may have been even more disappointed that it was Ammann’s George Washington Bridge that represented the century of progress. That the hands did appear as part of the design of an official first-day cover envelope may have been but small consolation.
Though it could be said that the George Washington Bridge was indeed the most significant structure to mark the century of progress since the founding of the American Society of Civil Engineers, an equally strong argument might have been made for not including it, or for employing the image of any one of several other bridges. After all, the George Washington was over twenty years old in 1952, making it more a symbol of eight decades, rather than a century, of progress. Had nothing of significance happened in bridge engineering, if that was indeed to be the metaphor for progress, since 1931? The light suspension bridges with sleek girder-stiffened decks that culminated in the Tacoma Narrows Bridge were not suitable candidates, for obvious reasons, but it could also be argued that the George Washington itself made engineers do what they did to those bridges. And what of the Golden Gate Bridge? Did it not represent progress beyond the George Washington? In short, the George Washington was a curious choice for the stamp. To understand why such a choice was made, however, requires a detour onto some routes of engineering progress that remain incompletely mapped to this day.
After the George Washington demonstrated that a stiffening truss was not absolutely necessary for the success of a suspension bridge, roadways supported by shallow stiffening girders were a natural development. As we have seen, the thin, ribbonlike profile provided by such designs was in keeping with the aesthetic goals of the time, and so Ammann, Steinman, Moisseiff, and their contemporaries were designing bridges with more and more slender profiles. Problems had begun to appear in bridges built as early as 1937. The Fykesesund Bridge in Norway, which had a 750-foot span suspended by rolled I-beams, and the Golden Gate Bridge, which had a conventional truss, oscillated in the wind, but it was the eight-hundred-foot span of Steinman’s own Thousand Islands Bridge over the St. Lawrence River, completed in 1938, and the 1,080-foot span of his Deer Isle Bridge in Maine, opened in 1939, along with Ammann’s Bronx-Whitestone Bridge, finished that same year, that drew the greatest attention to the problem, especially with the collapse of the Tacoma Narrows, which had essentially the same plate-girder construction as these.
Official first-day cover and U.S. postage stamp commemorating the centennial of engineering in America, incorporating, respectively, David Steinman’s hands working on plans for his not-to-be-realized Liberty Bridge and Othmar Ammann’s George Washington Bridge (photo credit 6.12)
Even before that disaster, Steinman and Ammann disagreed as to how best to retrofit their wavy bridges. Both of Steinman’s spans had been fitted with cable stays that were stretched between points on the tower near the roadway and the suspension cables. Thus installed, they were designed to stay, or steady, the main cables, and thereby check oscillations of them and the suspended roadway to an acceptable level. Ammann’s Bronx-Whitestone Bridge, on the other hand, had cables stretched between the tops of the towers and the roadway, which proponents believed would check the motion of the roadway directly. Within a month of the collapse of the Tacoma Narrows Bridge, which had been fitted with cable stays of yet another kind, Engineering News-Record published separate articles on the alternatives endorsed by Steinman and Ammann. Some time after these pieces appeared, Steinman brought the issue out in the open with a letter to the editor in which he challenged the implication that Ammann’s solution was found to be preferable to his own after “elaborate tests on a model conducted at Princeton University.” In fact, Steinman contended, his system of cable stays was not included in the tests, which were carried out for the Triborough Bridge Authority.
Terminology used for various means of attempting to suppress or reduce oscillations of suspension-bridge decks (photo credit 6.13)
Steinman concluded with nine reasons why he believed that the system adopted to steady the Bronx-Whitestone was “less efficient and effective than the system previously successfully applied on the Thousand Islands and Deer Isle bridges.” Among his reasons were factors relating to temperature changes, tower flexibility, side-span motion, torsional oscillations, and various technical details having to do with the nature of harmonic motion. The letter was followed, in the same issue, by a response from Ammann, who labeled as “valueless” Steinman’s “general unqualified assertions” that were “unsubstantiated” by analysis or experiment, and speculated that his criticism of the Bronx-Whitestone solution was motivated by Steinman’s “unsuccessful attempts to sell to the Triborough Bridge Authority his services and the use of his patented stay ropes which he endeavors to advertise as being superior to anything else.” In an attempt to refute some of the more technical of Steinman’s points relating to the dynamic behavior of bridges, Ammann revealed some of his own prejudices: “They involve such a complex problem that no one, not even the most learned physicist, could make a reliable analysis without experimental investigation. Dr. Steinman’s medley of arguments is pure guesswork expressed in impressive sounding scientific words.” Extensive studies involving models were required to resolve the matter, according to Ammann, and all installations called for “constant watching” to be sure they did not slip the way those on the Tacoma Narrows Bridge had done. The report of the committee of Ammann, von Kármán, and Woodruff on the collapse of that bridge gave no acknowledgment of the disagreement with Steinman over the form that stays should take. Steinman would later tell Engineering News-Record that the committee was composed of his “competitors” and that he was left out.
Politics and personalities can most easily enter where there are no incontrovertible solutions to technical problems, for the analytical difficulties can be horrendous and may rest upon assumptions that can always be called into question. Model tests, including the computer-based ones that are possible today, are also subject to criticism for their assumptions, and even when these are agreed upon, there can never be an exhaustive study of all possible conditions under which the bridge and its cable systems can operate. As for the “most learned physicist” that Ammann referred to, the analysis of such an individual, who might be a onetime academic like Steinman, remains a sore point among engineers to this day, for physicists tend to deal with such idealized systems that many bridge engineers fail to see the analyses as representing real bridges in real winds. Indeed, the problem epitomized by the Tacoma Narrows Bridge continues to stir controversy and debate among theoreticial engineers, practical engineers, and physicists alike. Whatever explanations of that collapse may be claimed or proposed remain open to the accusation that they are pure theory, for the simple reason that the very phenomenon they are intended to explain—namely, the actual oscillation and collapse of a full-scale suspension bridge across the Tacoma Narrows—is not available for verifying the theory. As for the retrofitted bridges of Steinman and Ammann, they have been made even more difficult to analyze with the added complications of their stays and stiffening systems. Though Steinman’s cable-stay solution was never admitted to be superior to Ammann’s, the latter’s Bronx-Whitestone Bridge was finally retrofitted with the stiffening trusses that essentially made the question of cable stays moot, and incidentally destroyed the bridge’s sleek lines.
&nb
sp; Thus, when it came time to decide what bridge to put on a stamp commemorating a century of engineering, the choice between an Ammann reality and a Steinman dream also became a choice between the two camps of engineering approaches and responses to the Tacoma Narrows collapse. Furthermore, since the centennial of the American Society of Civil Engineers was being viewed as an occasion to define the centennial of the profession of engineering itself in America, that organization no doubt had desired to have a say in whose bridge should be pictured on “their” stamp. They would naturally turn to the work of Ammann, who after his break with Lindenthal had become the consummate organization man. He was more identified with bridges than anyone in New York, where the headquarters of the American Society of Civil Engineers was located, and his George Washington Bridge was the topic of an entire volume of the society’s Transactions. This must certainly have made a portrayal of that bridge preferable to a photograph of the hands of Steinman, who in his promotion of professional-engineering registration could actually have been seen as a threat to the oldest professional-engineering group in America. In 1953, the year after the stamp was issued, Ammann was made an Honorary Member of the society, thus achieving its coveted “Eminence Grade” of membership. Steinman, on the other hand, continued as an ordinary Member and was never recognized by the ASCE as having achieved “eminence in engineering.”
Among the reasons for Steinman’s lack of recognition by some segments of the engineering establishment must certainly have been his insistence on keeping the embarrassment of the Tacoma Narrows collapse more in the forefront of discussion than many engineers, such as Ammann, would have liked. The more it was talked about, the more attention it might call to the underlying influence of the George Washington Bridge, and to other spans built in the design climate of the 1930s. In the early-to-mid-1940s, Steinman’s desire to understand and articulate theories on the stability of suspension bridges, not to mention to build still larger ones, had brought plenty of attention to the most ignominious event in engineering history. But his interest in bridges became nicely complemented by his desire to pursue literary endeavors.
Engineers of Dreams: Great Bridge Builders and the Spanning of America Page 43