For about 350 years, humanity’s most innovative portable computer was something called a slide rule. Just as typewriters once symbolized the writer, slide rules symbolized the engineer.
These analog calculators came in metal, wood, plastic, and even bamboo, and could be found all over the world. Its functions included calculating higher-order multiplications, exponents and logarithms, among other mathematical operations. They were typically long and rectangular with a retractable center segment and featured dense fields of letters, lines, and numbers stacked on top of each other.
They seemed almost comically abstruse, as if they could be used as paddles in the hazing rituals of a math fraternity.
Non-nerds struggled to make sense of them. Then, in the early 1970s, lightweight electronic calculators became widely available. The slide rule market collapsed and the manufacture of new devices virtually ceased.
One day, about 20 years later, a middle-aged avionics engineer named Walter Shawlee was looking through a drawer in his home in Kelowna, a midsize city in British Columbia, when he came across his old slide rule from high school. .
It was a pocket-sized Deci-Lon from Keuffel & Esser, model 68-1130, with a slender ivory body and a delicate transparent slide case. Both had stood the test of time. Shawlee recalled that when she was a teenager she had spent six months saving money to buy it.
Inspired by this encounter with his youth, he created a website dedicated to slide rules. Before long, nostalgic mathematical geniuses from decades past arrived at the site. The emails arrived in Mr. Shawlee’s inbox. He began spending eight hours a day researching, buying, fixing and reselling old slide rules.
“Are you trying to corner the market on slide rules?” his wife, Susan Shawlee, asked nervously, The Wall Street Journal reported in 2003.
The Institute of Electrical and Electronics Engineers’ Spectrum magazine determined in 2007 that Shawlee had, in fact, “cornered the global market.”
“He’s Mr. Slide Rule,” a Texas engineer and slide rule enthusiast told The Journal. “Walter knows everyone in the slide rule business.”
Shawlee died on September 4 of last year at her home in Kelowna. She was 73 years old. The death was not widely reported at the time, and The New York Times was notified about it just last month. His wife said the cause was cancer.
Shawlee wasn’t just a slide-rule sentimentalist in thrall to the teenage geek’s memories. He argued that slide rules had intrinsic appeal for several reasons.
He saw dignity, for example, in its solidity and design. In a 1999 profile in The Times, Mr. Shawlee described slide rules as “the techno-kids’ version of a sword.” About his website, the universe of slide rules, contrasted them with digital technology. “In 50 years, the computer you’re using to view this web page will be a garbage dump,” he wrote, “but your trusty slide rule will be just fine.”
For Shawlee, the loss of durability represented by slide rules belonged to a broader narrative of decline. “When we used slide rules every day in the 1960s, we were able to send people to the moon,” Shawlee told The Journal. Speaking to The Times, she observed: “People who grow up with calculators have no number sense.”
Joe Pasquale, a professor of computer science and engineering at the University of California, San Diego, has taught classes on the “history, theory and practice” of slide rules, including a survey of “the best slide rules ever created,” as he he said that in a Course Description.
In an email, Professor Pasquale explained the pedagogical value of slide rules. Calculators tend to replace the human mind, requiring users only to enter numbers and “blindly accept” a result, leading to a loss in the user’s own ability to calculate – “and more generally, to think,” the professor wrote. Pasquale. While slide rules require active participation, he added, “expanding the mind’s computational capacity.”
It was fortunate for Mr. Shawlee that a surprising number of people shared these views. In the early 2000s, he earned $125,000 a year fixing and reselling slide rules. The company paid for the education of his two children and sent one of them to law school. His customer base took its most organized form in society shoulda club named after William Oughtred, the Anglican minister generally credited with inventing the slide rule in the early 1620s.
Shawlee’s website developed a subculture of its own, with a network of slide-rule fanatics from Arizona to Venezuela to Malaysia digging on Shawlee’s behalf among the moldy items of old stationery stores, estate sales, and school district warehouses in search for calculation rules. In Singapore, an official, Foo Sheow Ming, visited the back room of a bookstore and found 40 unopened boxes containing more than 12,000 slide rules of multiple varieties. On his website, Shawlee called the find “the absolute El Dorado of slide rules,” and Foo told The Journal it was “the mother lode.”
Because government regulations prohibited him from making a profit on the products, Mr. Foo sold the slide rules to Mr. Shawlee at a discount. “It all depends on the excitement of the hunt,” he told The Journal.
Mr. Shawlee’s inventory includes notable artifacts of the history of science. He offered a slide rule made for machine gun operators, with windage, elevation, and range calculations. He offered a slide rule for measuring metabolic rates, with different adjustments for age, sex and height. And he used his website to explore hidden depths of slide rules, writing, for example, about slide rules. made by the US government to calculate the effects of nuclear bombs.
“Do you need to know the optimal explosion height for that new nuclear bomb you just bought?” Mr. Shawlee asked in a mock sales pitch. “How about the radius of the high-confidence destruction zone, or the temperature at an exact distance from the nuclear weapon that just exploded down the block? “These babies can answer all those burning questions while being flamed into free ions and radioactive dust at about 1,300 mph.”
He also sold slide rule cufflinks and tie clips, which in some cases had been manufactured by major slide rule manufacturers as promotional items during what Shawlee called “the golden age of slide rules.” Tie clips proved so popular in the slide rule universe that Shawlee worked with a small foundry to begin making them himself.
Over time, its clients included a weather station in Antarctica, where many electronic devices could not withstand the cold; photo editors responsible for resizing images (they like slide rules for their clear display of different values for the same ratio); an archaeologist who discovered that calculators became too dusty to function properly during excavations; pharmaceutical company Pfizer, which gave away slide rules during a trade show; slide rule enthusiasts in Afghanistan and French Polynesia; and “NASA guys”, Mr. Shawlee said Engineering times in 2000.
Walter Shawlee II was born on November 27, 1949 in Los Angeles. Her mother, Joan (Fulton) Shawlee, was an actress known for playing Sweet Sue, the leader of the “girl gang” at the center of the film “Some Like It Hot” (1959), and for playing Pickles Sorrell. . recurring character on “The Dick Van Dyke Show” (1961-66). His father was a hotel concierge and a painter specialized in marine scenes.
At age 14, Walter worked in an electronics surplus store and devotedly read magazines like Electronics World. He studied engineering and mathematics at the University of California, Los Angeles before dropping out. He worked in various positions, including as an assembly line welder at a Volvo factory in Sweden, before founding Northern Airborne Technology, a successful aviation communications company, in Kelowna. He sold the company in 1992.
After that, he became a contract repairman and inventor, helping companies design, for example, machines that could smoothly apply labels to a variety of fruits. He repaired and resold devices, including signal generators, high-voltage rectifiers, and cathode ray tubes.
He and his wife met at UCLA and married in 1971. In addition to her, he is survived by his children, Walt III and Rose Shawlee, and his half-sister, Angie Barchet.
When The Journal visited Shawlee’s home, there were about 1,000 slide rules scattered across the dining room table, Mr. Shawlee’s office and the family sauna. “I know my wife would like to have her dining room back soon,” he told Spectrum magazine.
In a phone interview, Shawlee said thousands of devices were still in the family’s home. She said she planned to continue selling them. As far as she knows, there is no prospect of another collector-expert-repairer-dealer-romantic like Mr. Shawlee emerging in “the slide rule business.”