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  • Courtesy photo

    Pedro Perez kneels and checks the workings of a 320-foot-long slide rule in front of Alvirne High School on March 22, 1979.
  • Courtesy photo

    Pedro Perez kneels and checks the workings of a 320-foot-long slide rule in front of Alvirne High School on March 22, 1979.
  • Courtesy photo

    This handmade sign, in front of Alvirne High School on March 22, 1979, draws attention to the senior class' accomplishment.
  • Staff photo by Don Himsel

    A typical slide rule is a foot long or so - 319 feet shorter than the version built by Alvirne students back in 1979. This user is sliding the "cursor," which helps keep track of answers.
  • Staff photo by Bob Hammerstrom

    Alvirne class of '79 yearbook and Guinness Book of World Records, where the largest slide rule was recorded.

  • Staff photo by Bob Hammerstrom

    Alvirne class of '79 yearbook and Guiness Book of World Records, where the longest slide rule was made by students. Photo on the left show the slide rule.

Wednesday, April 21, 2010

Then-seniors at Alvirne recount how record slide rule put together

HUDSON – The mystery of Alvirne High School’s world-record, 320-foot-long slide rule from three decades ago has been solved, mostly.

Only one question remains: Where is it now?

After the enormous, wooden contraption was laid out in front of the school on a crisp March morning 31 years ago, proving to be so long that students had to change the calculation so they wouldn’t block the driveway; and after The Telegraph had published a picture of it, so the Guinness Book of World Records would acknowledge Alvirne’s work in the 1980 edition; and after the school’s senior class had celebrated their accomplishment by taking their own pictures for the school yearbook – after all that, what happened to the slide rule?

“One time I saw the center piece, one 8-foot section, down in the basement of what used to be the old historical society, but I don’t know for sure,” said Pedro Perez, who was a senior in 1979 when he instigated the project. “We were frugal. I seem to recall the remaining sections were returned to the shop as stock.”

Alas, says Hudson Historical Society member David Alukonis, no portion of the device ended up with the keepers of town history as far as he knows. And Alukonis should know, because he was a member of the 1979 senior class, and is even featured in The Telegraph’s photograph from that era.

“Maybe it’s in a barn somewhere, but I’ve never encountered it,” Alukonis said Monday.

Memory of this most unusual senior project had faded over the decades, but it returned last week for an unfortunate reason: The death of Jim Reed, who was an industrial arts teacher at Alvirne for 32 years.

Reed passed away April 11 at age 79, and his obituary for The Telegraph mentioned his role in creating a world record slide rule.

This intrigued the paper and led to a story in The Sunday Telegraph that detailed an inability to find out much about this project. That story drew the attention of Debbie Hanks of Hudson – who was Debbie Cuthbertson when she helped with the project as an Alvirne senior – and she contacted Perez, who is now a nuclear engineer in Virginia.

“My class, a couple of the seniors, we were looking for something we could do to get some recognition to the school,” Perez said. Alvirne had only opened a couple of years earlier. “We wanted to do something unusual, at the same time reflecting science and technology.”

Even in 1979, the calculating devices known as slide rules were becoming outdated, as the first handheld electronic calculators showed up in workplaces and schools. Not even centuries of being an obligatory tool of scientists could save the “slipstick” from eventual irrelevance, but in 1979 they hadn’t quite disappeared, particularly if your father was an engineer.

“I remember my dad using one,” said Hanks.

Perez, whose father was a civil engineer who worked for the company that built the Seabrook nuclear power plant, has similar memories. So when he learned that the world record slide rule was “only” 204 feet long, he decided to try to break it.

Perez said Mr. Reed took the weird idea in stride and gladly helped the senior design, build and assemble 40 separate 8-foot-long sections, made from ripped wood stock in the machine shop.

“He was very supportive. We became good friends,” said Perez of the teacher. “A lot of the work we had to do after school – and he would stay with us, because you could not let the students (in the shop) unsupervised.”

The result, Perez admits, was not a model of calculating accuracy.

Slide rules use logarithms to simplify calculation. Longer slide rules can hold more detailed logarithmic marks, allowing more detail in the answer. A standard 10-inch slide rule is accurate only to three significant digits but the current world record, a 350-footer made by a retired engineer in Texas, can do calculations to six significant digits.

In theory, the Alvirne rule could also have been that accurate, but the markings were drawn on a long, long roll of cash register tape affixed to the wood on its record-breaking morning, and Perez said they were only sufficient to do a simple multiplication.

More precision wasn’t possible, Perez said, partly because it was tough getting high school seniors overly concerned about niggling details when graduation was barely two months away. After all, this was happening too late to be included on college applications.

In a way it’s amazing that they were able to get a group of teenagers to show up at school just after sunrise – they started early to make sure they’d have enough time to assemble the slide rule and do the calculations – for something so unusual.

“We were a pretty geeky class,” said Hanks. Among other things, she said, they successfully petitioned officials to create a Latin course.

The slide rule might not have been a thing of calculating precision, but it was impressive to behold, Alukonis said: “I remember how it took up the whole front lawn, from one end of the building to the other.”

Perez says he had planned to use it to calculate 3 times 2, but that involved extending the sliding portion so far that it would have blocked the driveway. He made a last-minute change, which was easier said than done: The slide rule was so unwieldly that it took a half-dozen people, each dragging a dowel attached to the slider as handles, to shift the slider.

“We had to precisely align the numbers on the scales, and just to move something that 320 feet a couple of inches, coordinating all those folks pushing at once, wasn’t easy,” Perez said.

It was enough for the Guinness folks, who included a listing about the accomplishment in the 1980 book of records.

These days the record survives in a few fleeting references online and dog-eared copies of the 1980 book. A group of college students in Illinois built a 323-foot slide rule later that year and bumped Alvirne from follow-up editions of the Guinness records.

The Telegraph published a photo in its March 22, 1979, edition, showing Perez and others working away – it was taken by Dean Shalhoup, who still writes for the paper, and was headlined “The Long, Winding Slide Rule” by some Beatle fan of an editor – and the rule itself was left on the front lawn for several days.

After that, who knows? High school graduation swamps the memories of those involved. Nobody recalls taking it apart, but presumably Mr. Reed oversaw the work, and if any piece was saved, he might have saved it. His family members say none of them know anything about it.

Still, perhaps somewhere the central section exists.

If it does, the owner needs to turn it over.

There on the back, written by Hanks at Perez’ request, is a quotation in Latin from the poet Seneca that sums up the class’ adventure. Translated into English, it reads “There is no great genius without some touch of madness.”

David Brooks can be reached at 594-5831 or