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TIME-SENSITIVE MATERIAL

Henry Petroski

e mark time differently than we mea- other digit repeated three times. However, the Wsure distance. Although none of us is freshness of the preface numeral 2, after a millen- likely ever to have seen a new car nium of years beginning with the numeral 1, odometer read 000000, we infer that that was in- seems special and remarkable. The change in the deed the reading when it was installed at the facto- prefix attracts the kind of attention that a decadal ry. As the car was driven from the assembly line to birthday or anniversary does, with just about its parking lot, the wheels began to turn and the everyone forgetting or abandoning the fact that machine registered tenths, miles, tens of miles and we measure age by different numerical rules that so forth as they were reached. With dates we mark we mark dates. From newspapers and maga- the days, months and years before they are com- zines, and now including this column, to profes- pleted, however, and so from the instant after mid- sional societies and organizations, millennial night on New Year’s Eve 1999, we by custom write madness has triumphed over reason—with lists the date as 01/01/00, even though it will be anoth- modified by top, best, greatest and other superla- er 24 hours before that day is completed. And it tives being voted on, compiled and disseminated. will not be until midnight on 12/31/00 that the year 2000 is completed, and with it the 20th century. The Best of Lists; the Worst of Lists Y2K notwithstanding, the second millennium will Lists are always interesting, of course, even to en- really end not with a bang but a whimper. gineers—and even though we realize the arbitrari- Engineers and scientists know all this, of ness of numbers, including “round” numbers end- course, but it would have been difficult for us to ing in 0 or 5. It is only an accident of our base-ten persuade the mass media to hold out for an en- system and the multiple recurrence of 5, we might tire year before recognizing the arrival of the 21st tell ourselves rationally, that make top-10 lists or century and the “new millennium,” which truly 25th anniversaries special, but we get caught up in begins on 01/01/01. If we were to insist on wait- the process of compiling lists, perhaps because lists ing until 2000 turned into 2001 for our celebra- appear to have a rationality of their own, a begin- tions, we would risk being seen as spoilsports at ning and an end, an ordering, a definiteness, a de- best or hopelessly out of date at worst. Ironically, cisiveness. The phenomenon is nothing new. it has been the focus on the very technical prob- A survey conducted 70 years ago by the Amer- lem of Y2K computer compliance, a problem ican Society for the Promotion of Engineering Ed- closely associated with engineers and scientists, ucation sought to identify “the outstanding engi- or at least computer scientists, that has empha- neers of the past twenty-five years; also those who sized the four-digit year, which in turn has dri- might fairly be considered the greatest engineers ven the focus of the date change to the odometer- of all time.” In addition to the still-familiar Edison like event of 1999 turning into 2000. The year and Ford, listed among the outstanding engineers change is being treated as a counting event, of the first quarter of the 20th century, there were when in fact all it is, is a marking event. John F. Stevens and George W. Goethals, who Not since the upside-down year 1961 almost played central roles in the construction of the four decades ago or the palandromic and mirror- Panama Canal, completed in 1914. These two en- image year 1881 over a century ago has a new gineers were also identified as among the greatest year’s number been treated as such an icon. Such engineers of all time, but a 1974 article about oddities will not occur again until the numero- Stevens in Civil Engineering magazine was entitled, logically rich seventh millennium gives us the “The Forgotten Engineer.” (Ferdinand de Lesseps, year 6119, and the ninth millennium gives us the French entrepreneur who pushed the canal 8118. In terms of numerical patterns, 1999 and project, was named the fifth greatest engineer of all 2000 are identical—a single digit followed by an- time, even though he was not an engineer.) Number 10 on the list of outstanding engineers Henry Petroski is A. S. Vesic Professor of Civil Engineering of the first quarter of the 20th century was Ralph and a professor of history at Duke University, where he also Modjeski, the builder of Philadelphia’s Benjamin chairs the Department of Civil and Environmental Franklin Bridge, completed for the nation’s 150th Engineering. Address: Box 90287, Durham, NC 27708-0287 birthday, in 1926, and thus a name more familiar

© 2000 Sigma Xi, The Scientific Research Society. Reproduction 18 American Scientist, Volume 88 with permission only. Contact [email protected]. identifying the 125 most significant innovations Outstanding Engineers that shaped the industry during the magazine’s (ca. 1930) lifetime and also the industry’s 125 most influen- tial people who made contributions since the Top engineers identified by a survey magazine’s founding in 1874. Eads made ENR’s of deans of engineering list, but Modjeski did not. (John’s son,Washington Outstanding Engineers of the Roebling, and his wife, Emily Warren Roebling, Past 25 Years (ca. 1930) are on the list as project managers, but the elder Herbert C. Hoover Roebling, who died in 1869, did not qualify.) Charles P. Steinmetz Should ENR identify the top 150 people to cele- Thomas A. Edison brate its 150th anniversary in 2024, it should not John F. Stevens surprise anyone if on second thought, and in the John Hays Hammond context of a longer history, some of last year’s 125 George W. Goethals do not make the cut 25 years hence. Lists are George Westinghouse products of their times. Guglielmo Marconi In the wake of the Centennial of Engineering Henry Ford celebration, which took place in 1952 and coincid- Ralph Modjeski ed with the 100th anniversary of the founding of Benjamin G. Lamme the American Society of Civil Engineers, the coun- Michael Pupin try’s first national engineering professional society, John R. Freeman the ASCE undertook to identify outstanding Clemens Herschel American civil engineering works. The 1955 list re- Gustav Lindenthal flected the importance of water supply, treatment and control in the first half of the 20th century, with Greatest Engineers of All Time (ca. 1930) the majority of the “seven wonders” being in that James Watt category. When the mid-century list was updated Leonardo da Vinci in 1994, the water works were largely displaced by Thomas A. Edison works of transportation. Each list contained a sin- William B. Eads1 gle bridge, with the San Francisco-Oakland Bay Ferdinand de Lesseps Bridge being displaced by the Golden Gate Bridge Charles P. Steinmetz on the newer list. The mid-century list recognized George Westinghouse the greater engineering achievement of the lesser- John Ericsson known bridge, but the late-century list, which Archimedes seemed to be driven more by popular than by tech- Lord Kelvin nical criteria, was topped by the notable but when John L. Roebling2 constructed state-of-the-art span that had become George W. Goethals the tourist symbol of San Francisco. John F. Stevens

1 most likely James Buchanan Eads Seven Modern Civil Engineering 2 most likely John A. Roebling Wonders of the United States in 1930 than today. Two other bridge builders Identified by the American Society were also included on the 1930 list of greatest en- of Civil Engineers in the wake of its centennial and updated almost 40 years later gineers of all time, but that is not to say that they got any respect. James Buchanan Eads was Seven Wonders of the United States (1955) misidentified as William B. Eads and a John L. 1 Chicago’s Sewer Works Roebling was listed, presumably John A. Roe- 2 Colorado River Aqueduct bling, the designer of the Brooklyn Bridge. 3 Empire State Building Also included on the list, among Archimedes, 4 Grand Coulee Dam Leonardo and Lord Kelvin, was John Ericsson, 5 Hoover Dam now hardly a household name. Yet this builder of 6 Panama Canal the Monitor ironclad “revolutionized navigation by 7 San FransciscoÐOakland Bay Bridge his invention of the screw propeller,” as stated on the little known but prominent monument to Eric- Seven Wonders of the United States (1994) sson that stands in Washington, D.C. to this day, 1 Golden Gate Bridge beside the Potomac River, next to the Arlington 2 Hoover Dam Memorial Bridge and a stone’s throw from the Lin- 3 Interstate Highway System coln Memorial. Lists do not have the staying pow- 4 Kennedy Space Center er of monuments, but neither ensures familiarity. 5 Panama Canal Engineering News-Record, the distinguished 6 Trans-Alaska Pipeline magazine of the construction industry, celebrated 7 World Trade Center its 125th anniversary during 1999, and it did so by

© 2000 Sigma Xi, The Scientific Research Society. Reproduction 2000 January–February 19 with permission only. Contact [email protected]. Greatest Engineering Achievements The National Academy of Engineering, which Outstanding Engineering Achievements celebrated its 25th anniversary in 1989, elected to 1964 Ð 89 mark the occasion by naming 10 outstanding achievements of the period. These included the Named on the occasion of the 25th anniversary of the National Academy of Engineering moon landing, the microprocessor, the jumbo jet, lasers and fiber-optic communication. The list 1 Moon Landing was not greeted with unanimity, especially 2 Application Satellites among civil engineers, who saw as also deserv- 3 Microprocessor ing of recognition such neglected achievements 4 Computer-Aided Design and Manufacturing as the cable-stayed bridge, the tubular skyscraper 5 CAT (computer-aided tomography) Scan and the interstate highway system, which, al- 6 Advanced Composite Materials though not exactly invented during the period, 7 Jumbo Jet certainly flourished then. 8 Lasers In a booklet promoting the NAE’s outstand- 9 Fiber-Optic Communication ing engineering achievements, the 25-year period 10 Genetically Engineered Products ending in 1989 was described as one that “wit- nessed more advancement in technology and, consequently, greater change in the lives of peo- tendance voted for the five that were to be for- ple than any previous 25-year period in recorded warded to the NAE as the choice of the civil engi- history. The sentiment echoed that expressed 90 neers. The ASCE plans also to use the list com- years earlier in the New York Times, which on De- piled to help celebrate its own 150th anniversary, cember 31, 1899 carried a story on the 19th cen- which will occur in the palindromic year of 2002. tury. As quoted by Stephen Jay Gould in his It will be interesting to see which “seven won- Questioning the Millennium, the story asserted that ders” survive from the 1994 list. “Tomorrow we enter upon the last year of a cen- The American Society of Mechanical Engineers tury that is marked by greater progress in all that took a different tack. It listed in alphabetical order pertains to the material well-being and enlight- in its magazine 20 “broader topics encompassing enment of mankind than all the previous history some specific technologies,” including air condi- of the race.” We can only speculate on what will tioning and refrigeration, the airplane, computer- be written of the 21st century. aided engineering technologies, plastic manufac- To celebrate not an anniversary of its own but turing and xerography. A reply card was provided the arrival of the year 2000, a few years ago the for readers to rank order their choices of 10 top National Academy of Engineering embarked on achievements. The final top 10 of the ASME will a project entitled Greatest Engineering Achieve- each be the topic of a feature article in Mechanical ments of the 20th Century. The idea, which grew Engineering during the year 2000. The top five out of a desire to convey the importance and ex- achievements were submitted to the NAE. citement of engineering to the public, and espe- Tau Beta Pi, the honor society founded in 1885 cially to young students, was to focus on “the as the engineering counterpart to Phi Beta Kappa significant impact that engineers and engineering (see “Engineering,” March–April 1998), took a have had on the quality of life in the 20th centu- more parochial approach in seeking two lists from ry.” To reduce the chance of omitting—or at least its members “in an attempt to identify as many considering—achievements from technological- outstanding Tau Beta Pi engineers as possible.” ly less visible, sweet or glamorous branches of Readers of The Bent, the magazine of the society, engineering, the project was designed to be a col- were asked to list the top 10 engineers of the 20th laboration between the NAE and professional or- century in addition to the top 10 engineering ganizations, including among others those repre- senting civil, mechanical, chemical and electrical engineers. In all, more than 60 engineering soci- Top 10 Responses to the American Society eties were asked to participate in the first phase of Civil Engineers Millennium Challenge of the project, which involved each society nom- inating no more than five candidates for the greatest engineering achievements of the century. Interstate Highway System The individual societies used different ap- Long-Span Bridges proaches to identify their outstanding projects. Dams The American Society of Civil Engineers termed Water Supply its effort the Millennium Challenge and asked its Airports 120,000 members to nominate civil-engineering Wastewater Treatment achievements, enticing the membership with Skyscrapers $1,000 prizes for the top 10 winning entries. The Rail Transportation nominations were judged by a panel, and a defin- Sanitary Landfills / Solid Waste Disposal itive list of 10 was announced in October at the Water Transportation (Canals and Ports) society’s annual meeting, whereupon those in at-

20 American Scientist, Volume 88 © 2000 Sigma Xi, The Scientific Research Society. Reproduction with permission only. Contact [email protected]. jective “to recognize engineering accomplish- Greatest Mechanical Engineering ments of the past and present, and to lay the Technologies of the 20th Century groundwork for future successes.” The week is designed to celebrate the profession and “to tell Identified by the American Society the rest of the nation of the many contributions of Mechanical Engineers and submitted to the membership to rank engineers make to everyday life.” Professional or- ganizations and groups sponsor special Engineers Agricultural Mechanization Week activities, which include lectures intended Air Conditioning and Refrigeration for the general public and demonstrations for Airplane school children to help them “relate math and sci- Apollo Program ence to the world around them” and not inciden- Automobile tally to make them aware of engineering as a pro- Bioengineering Processes fession and as a possible career choice. Bottle Manufacturing National Engineers Week is thus a natural fo- CAD/CAM and other Computer- rum within which to announce the Greatest Engi- Aided Engineering Technologies neering Achievements of the 20th Century. The Codes and Standards announcement should attract considerable inter- Food Processing est, for regardless of what we think of millennium Gas Turbine Technology madness, anniversaries, top 10 lists and the like, Integrated Circuit Mass Production the naming of the greatest engineering achieve- Glass Manufacturing ments provides an opportunity for us to reflect Microelectromechanical Systems on the nature and importance of engineering and Numerically Controlled Machines and Robots its virtually countless contributions to making Paper Converting daily life so much more comfortable and conve- Plastic Manufacturing nient than it must have been a century ago, let Power Generation alone a millennium ago. The lists may not sur- Ribbon Machine vive the judgment of history, but they should cer- Xerography tainly present valuable and instructive barome- ters of fin de siècle preferences for engineers, historians and laypersons alike to ponder in achievements of the period. Those needing decades, centuries and millennia hence. prompting were referred to the society’s Web site (http://www.tbp.org), which “lists hundreds of famous Tau Beta Pi engineers and significant en- gineering accomplishments of the century.” The nominations served as the basis for producing a ballot, and the results are to be announced in May 2000 at the national awards ceremony of the American Association of Engineering Societies, another collaborator in the NAE project. The grand list of the greatest engineering achievements of the 20th century has by now been determined by an anonymous panel of NAE members representing the various engineering disciplines, but the list has been released only to the participating societies, who are working at co- ordinating the individual press releases. The tim- ing made it impossible to include the final list in this column, of course, but the greatest achieve- ments are scheduled to be announced publicly during National Engineers Week, which takes place each year during the week containing the traditional date of George Washington’s birthday (February 22), or February 20–26 this year. This is consistent with the project’s being “part of a larg- er public awareness campaign” that is “meant to stimulate public discussion about engineers and the contributions of engineering.” National Engineers Week was initiated in 1951 by the National Society of Professional Engineers, another collaborator in the NAE’s Great Achieve- ments Project. It is now cosponsored by many of the major engineering societies and has as its ob-

© 2000 Sigma Xi, The Scientific Research Society. Reproduction 2000 January–February 21 with permission only. Contact [email protected].