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A Zipper Day Mystery

LEYLA DOSS, HOST: May 19th marks the end of capacity restrictions on most New York businesses, and we all know what that means: putting on real pants. After over a year of Zoom meetings in sweats, New Yorkers are zipping up their office wear again. Kate Stockrahm sets out to report on “National Zipper Day,” only to find out the date’s origin, much like the fastener itself, is more complicated than it first appears.

KATE STOCKRAHM: If you want to talk zippers, Fred Klingener is a good place to start.

FRED KLINGENER: The subject line in the email was “Do you want to talk about zippers? And my response was sure.

STOCKRAHM: Klingener is the grandson of Gideon Sundback, the inventor of the modern zipper. He’s an engineer himself and takes zippers seriously.

KLINGENER: By the way, zipper people don't call themselves zipper people. We are fastener people.

STOCKRAHM: Okay, zipper people: not a thing. Fastener people: absolutely.


*And you’ll appreciate the Talon Fastener even more once you’ve worn that suit awhile.*

STOCKRAHM: A company called Talon produced this short film in 1938 to convince button people to become fastener people.

*You’re right, it does make the trousers a lot neater and smarter!*

*You bet it does*

STOCKRAHM: The film doesn’t mention any National Zipper Day on April 29th. So I asked Klingener about the date’s meaning.

KLINGENER: I frankly didn't know what April 29 was. It doesn't relate to anything we think of as foundations of the industry.

STOCKRAHM: That industry is zippers -- with over $4 billion in sales in the U.S. alone -- and “we” means fastener people. Klingener told me he’d be happy to talk more, but first I should read Zippers, the book on the fastener’s history.


STOCKRAHM: Zippers is over 250 pages long. 25 more if you count the references and footnotes. Clearly, someone had been down this road before me, and that someone was Robert Friedel. He also taught the History of Science and Technology at the University of Maryland for 35 years. Why write about zippers Professor Friedel?

ROBERT FRIEDEL: The deeper you get into it, the more intriguing it becomes… at least to me.

STOCKRAHM: Friedel agrees that Sundback, Klingener’s grandfather, invented the modern zipper. Sundback’s first design was nicknamed the Plako, and in Friedel’s book, you can see the Plako fastener’s patent was issued on April 29th, 1913. The date of National Zipper Day.

Great! Mystery solved, right? Wrong.

FRIEDEL: I suggest that the patent date is is perfectly worthless date to hang anything on because it depends on, you know, the lawyer schedule on the patent examiner schedule, and all that other stuff that had nothing to do, or very little to do, with the invention itself.

STOCKRAHM: Plus, Friedel’s book points out the April 29th design just didn’t work that well. It still required a violent tug to pull up and down. But it was an improvement on the zipper that came before it.

That’s right, before it. It turns out that the zipper wasn’t born of a sudden burst of inspiration, it was more of an evolution.

FRIEDEL: It's kind of a nutty notion, okay, that you're going to have this little slide device that will open and close a thing for you. Okay? And it takes 20 years to get it right.

STOCKRAHM: Friedel says another inventor, Whitcomb Judson, designed a fastener he called a “Clasp Locker” way back in 1893. And then improved it and patented it again in 1905. That second design was called the C-Curity fastener, and it was so fickle it had to be removed before each washing.

*Sure it won't jam?*

*Certainly not! Try it!*

*Won’t it rust?*

*Not a chance.*

STOCKRAHM: With a better sense of the historical complexities, I went back to Fred Klingener. I told him we celebrate his grandfather’s invention on the day it was patented. But Fred countered:

KLINGENER: March 20th. The Hookless #2… that was March 20th, 1917.

STOCKRAHM: Welp. You can’t win ‘em all.


STOCKRAHM: March 20th was the patent date for his grandfather’s model “Hookless #2,” an improvement on his earlier April 29th design. Fred emailed me a picture of the #2 patent and I had to admit, it’s the first fastener that truly looked like a modern zipper. And given its sales, it seems it worked better too.

*I don't know, I don't go in much for these new fangled ideas.*

*Well I'd certainly advise you to try it for a couple of weeks. Then I know you'll never go back to the old way!*

STOCKRAHM: The more I learned about its history, the less likely it seemed there could be a single “zipper day.” There were better and worse designs, a variety of patent dates, and a historian who said we shouldn’t even trust those dates. Plus, I soon learned, the term zipper wasn’t even trademarked until the 1920s -- a decade after the supposed zipper day.

So, I started over again. If you type in “National Zipper Day” on Google, one of the top hits is a librarian’s post in Michigan.

*Ring ring* You’ve reached Farmington Hills Community Center. Children’s services, this is Marie speaking.

STOCKRAHM: The kids that visit Maria Showich-Gallup know her as Miss Maria. She’s always on the lookout for interesting events to share with them, and that’s how she landed on Zipper Day. She pulled her primary source for the date, a two inch thick, dark blue reference book called Chase’s Calendar of Events.

MARIA SHOWICH-GALLUP: Okay, this is an old one. I have probably a more current one upstairs in the adult department. But yeah, they have anything and just like, everything in here.

STOCKRAHM: A Publisher’s Weekly blurb on the cover of this year’s Calendar of Events calls it “one of the most impressive reference volumes in the world.” Miss Maria showed the entry for National Zipper Day. Without any explanation, it marks the date of the patent as April 29th. Another dead end.


STOCKRAHM: Even if April 29th isn’t the best date for Zipper Day, I just want to know who decided it was. But as I dug deeper it became clear that what I, a librarian, and hundreds of Google results believed to be a fact, might just be a mistaken historical footnote.

Disappointed but determined, I reached out to someone who doesn’t know anything about the history of zippers, but who does specialize in finding the source of information.

EMILY BELL: The idea that there is an authentic national zipper day, when you think about it for two seconds, is slightly absurd.

STOCKRAHM: Emily Bell is the founding director of the Tow Center for Digital Journalism. She’s made a living researching the intersection of tech and reporting. As for Zipper Day,

BELL: I think I would call it marketing. It feels like something that was generated in order to draw attention to a product, to create a sales opportunity.

STOCKRAHM: I admit I hadn’t really considered this. Zipper Day might have just started out as a marketing gimmick. that after many years began to take on the weight of fact.

BELL: I think what's happened is you've struck... you're covering what you think is a fun story, and you have fallen into a rabbit hole // which is how do we know what we know? And who is sending us messages? And why? Where do they come from? And can we trace the source of them?

STOCKRAHM: I didn’t mean for this to become so started with zippers! But Bell says my quest is an example of how hard it is to pull truth out of an increasingly complex pool of information.

*I’m glad you fellas are really sold on this idea… you’ll find most men accept it without question.*

STOCKRAHM: National Zipper Day may be a marketing ploy, and it may very well have some basis in historical fact… albeit fact scattered across patent records, reference books, and websites. But, at least with Zipper Day, that confusion doesn’t matter much (unless you’re a fastener person).

BELL: I don't think anybody is going to march on the Capitol because of National Zipper Day. But the steps you went through in trying to establish “Is this thing that I'm told is true? Is it really true? How do we know what we know?” That's at the heart of this whole era of information disruption.

STOCKRAHM: So, next time you’re about to share a post, or a Tweet, or reach out to the grandson of a notable inventor about a supposed holiday, just remember to ask yourself first… is this another National Zipper Day?

Kate Stockrahm, Columbia Radio News.


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