When the weather is dank and windy or otherwise foul, walking across the Harvard Bridge, which spans the Charles River linking Boston and Cambridge, is a trek that has taken the measure of many a Harvard or MIT student. But late one autumn night in 1958, it was a student who took the measure of the bridge.

To be more precise (and precision is everything in the measuring business), the student in question on that particular night was one Oliver R. Smoot Jr. Then a hapless 5'7" MIT freshman and Lambda Chi Alpha pledge, he was rolled head over heels across the entire span. Though it seemed like a pure exercise in hazing and brotherly sadism, the stunt did add to the store of human knowledge: The length of the bridge was said to be exactly 364.4 smoots plus an ear.

Under the watchful eye of a senior brother, the pledge class of'58 carefully calibrated the bridge, painting marks every 10 smoots until they reached the Boston side of the river, where their fraternity house is located. Thus, a unique unit of measurement—not to mention a whole new tradition—was born. Successive pledge classes have picked a new color (most recently, a blazing red) and repainted the bridge's original smoot marks twice annually for the past 30 years.

Unfortunately, frat tradition pulled little weight with the Massachusetts Department of Public Works. Late in 1987 a final decision was made that the bridge's aging concrete was overdue for replacement, and plans for the $16 million overhaul did not at first include smoot preservation. Threatened with the extinction of their pet project, the Lambda Chi members raised a mighty hue and cry to "Save the smoots!" Soon they attracted the attention of the Boston press.

The protesters cast the threatened smoot removal as a quality-of-life issue. "Smoot marks make it possible for students to know how far they are from the other side without looking up," says Richard Lightburn, president of the fraternity chapter. "You can stay huddled down in your jacket and still know how far you have to go." Tracked down in Washington, D.C., where he is now the executive vice president of Computer and Business Equipment Manufacturers Association, the original Smoot offered scholarly support. "Smoots are no more illogical than feet or yards," says Oliver Smoot, now 48.

The smoot storm came as a surprise to the men accused of wrecking the legend, members of the construction crews working on the span. "It was just graffiti to us at first," admits Charles Madden, vice president of Modern Continental Construction Co. "Then fraternity members started coming by asking if we could deliver a couple of the 4,000-pound slabs with the smoot marks on them to the frat house." Says pledge Matt Beaumont, 18: "We take this very seriously. It's a very famous legend on campus." To preserve tradition, desperate measures were needed and recently taken. Beaumont and his pledge brothers set out with nearly a mile of kite string and painstakingly marked the precise intervals of existing smoot marks so they could be re-created when the bridge work is completed.

All of their efforts may be paying dividends. No less an authority than the Massachusetts Metropolitan District Commission, the government body in charge of the bridge, has gone on record in support of smoots. "We recognize the smoots' role in local history," says Leanne del Vecchio, the MDC's public information director. "That's not to mean," she quickly adds, "that the agency encourages graffiti painting. But smoots aren't just any kind of graffiti. They're smoots! If commemorative plaques and markers are not installed by the state once the bridge work is done, then we'll see that it's done."

Some students, however, have not been reassured by such promises. They are pushing for a more radical solution—that, after completion of repairs, there should be a fresh re-smooting, using the Son of Smoot. It happens that Stephen Smoot, the 21-year-old scion of Oliver R. Smoot Jr., is presently attending MIT and is ready to lay down his body length for the cause. "Fine with me," says Smoot the younger. He admits he is fond of the smoot legend, which has for him the status of "a favorite old family story."

His father also has no objection to a measured succession. Nevertheless he warns, "Stephen is taller than I am. He's 5'11", which might throw everything off." As for an encore performance at the age of 48, Smoot the elder politely declines. "It's a bit tiring, and its one of those things that's much more fun to do at 18," he says. Then, after a pause, he speaks of a cruel dilemma that can haunt anyone who exists as a standard unit. "My problem," he admits quietly, "is that I'm afraid they'll find out I've shrunk with age."

—Ned Geeslin, S. Avery Brown in Boston