Keeping track of numbers has always been part of what makes us human. So at some point along the way, we created a tool to help us keep count, and then we gave that tool a name. We called it: a calculator. But depending on what era you were born in, and maybe even what country, what constituted a 'calculator' varied widely.

Keith Houston wrote about the evolution of the calculator in his latest book, Empire of the Sum The Rise and Reign of the Pocket Calculator. It is exactly the kind of nerdery we like to get up to here at 99% Invisible -- history explained through the lens of an everyday designed object.

Empire of the Sum

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Today's episode features #1 Robert Caro superfan, Conan O'Brien.

The Power Broker by Robert Caro is a biography of Robert Moses, who is said to have built more structures and moved more earth than anyone in human history. And he did it without ever holding elected office. Outside of New York City, Robert Moses wasn't exceptionally well known. Inside of New York, he was mostly accepted by the media as simply the man who built all those nice parks. But The Power Broker, which is subtitled Robert Moses and The Fall of New York, changed all that. It is a tour de force of journalism, history, and biography. Roman also argues it's really fun to read and is strongly in contention for the best book ever written.

But there is something of a catch, which can hang readers up: the book is a daunting 1200 pages long. As influential and amazing as this bestseller is, many people own an unopened copy gathering dust on their bookshelf. But that is a crime because this book needs to be read or at least discussed at length on a podcast.

Roman Mars and Elliott Kalan (Flop House, Daily Show) are starting The Power Broker book club that will run through all of 2024 as bonus episodes and in this introductory episode, Conan O'Brien joins us to talk all things Robert Caro.

Breaking Down The Power Broker

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Roman note: This is one of my favorite episodes of all time. Should be a movie. Enjoy!

The tradition of the Tomb of the Unknowns goes back only about a century, but it has become one of the most solemn and reverential monuments. When President Reagan added the remains of an unknown serviceman who died in combat in Vietnam to the Tomb of the Unknowns in Arlington National Cemetery in 1984, it was the only set of remains that couldn’t be identified from the war. Now, thankfully, there will never likely be a soldier who dies in battle whose body can’t be identified. And as a result of DNA technology, even the unknowns currently interred in the tomb can be positively identified.

The Known Unknown

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The Cassette tape was great in so many ways, but let’s be honest, they never really sounded great.  But because the cassette was so much cheaper and easier to use and portable, a lot of people didn't care so much about the audio quality. They just wanted to be able to use something that they could carry around with them. The cassette’s other big advantage: it was easy to record on.

We talked to Marc Masters about his new book High Bias, about the history of the cassette. One chapter about concert bootleggers covers perhaps the greatest success story of the cassette: Grateful Dead live tapes.

Long Strange Tape

Plus we're featuring a bonus story that we produced in 2016 in collaboration with Benjamen Walker's Theory of Everything about a place where cassettes were of vital importance.

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In a lot of ways, Lincoln Heights, Ohio, sounds just like any other suburb. If you walk around town, you’ll hear kids playing outside the local elementary school. You’ll hear the highway that takes commuters down to Cincinnati. At the woods on the edge of town, the birdsong is delightful. The town feels calm and peaceful - at least, until the gunfire starts. Most weekdays, it begins in the morning, and lasts through the afternoon. Sometimes it goes past sundown, and occasionally into the weekends. Once the shooting begins, it comes in rapid-fire waves throughout the day. People say it makes it hard to focus or relax, and those who work the night shift say they can’t sleep.

The noise of gunfire isn’t from street violence. It all comes from an open-air gun range that’s owned by the Cincinnati Police Department.

Home on the Range

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In the mid-1900s, people flocked to Reno, Nevada -- not for frontier gold or loose slots, but to get out of bad marriages.  The city became known as the "Divorce Capital of the World." For much of modern history, it has been relatively easy to get married, and extremely difficult to get divorced -- and for a time, this was true in the New World as well. But Reno provided the cure: The Six-Week Cure.

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Most heists target gold, jewels or cash. This one targeted illegal seeds. As the British established their sprawling empire across the subcontinent and beyond, they encountered a formidable adversary — malaria. There was a cure — the bark of the Andean cinchona tree. The only problem? The Dutch and the French were also looking to corner the market in cinchona. And the trees themselves were under threat.

This week on 99pi, we feature a story from Stuff the British Stole, a co-production of ABC Australia and CBC Podcasts. So "grab a gin and tonic and come with us to hear how a botanical empire took off — and gave birth to a quintessential cocktail."

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For decades, society has dealt with people with dementia and other forms of cognitive decline by storing them away in unstimulating, medicalized environments. But around the world, a new architectural movement is starting to challenge that old paradigm. Designing environments where people with dementia can live as normally as possible, until the very end.

Model Village

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It’s hard to overstate just how important record album art was to music in the days before people downloaded everything. Visuals were a key part of one's experience with a record or tape or CD. The design of the album cover created a first impression of what was to come. Album art was certainly important to reporter Sean Cole, one particular album by one particular band: Devo. This is the story of Devo’s first record and the fight over the arresting image of a flashy, handsome golf legend on the cover.

Plus, former 99pi EP Katie Mingle gets the backstory of the Langley Schools Music Project LP, a haunting and uplifting outsider artist masterpiece.

This episode was originally broadcast in 2018

Devolutionary Design

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Over a decade after Elvis Presley’s death, the king of rock & roll took over headlines once again as Americans weighed in on which portrait of Elvis would be forever immortalized on a 29 cent US postage stamp. It was put to a popular vote: should the stamp feature an image of young Elvis at the start of his rise, or an older Elvis in his iconic white jumpsuit.

The resulting Elvis stamp eventually outsold every single commemorative stamp before and since.

You Ain’t Nothin But a Postmark

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