Now, that gives me pause! I'm pretty confident of my understanding of a bicycle. The author claims that people challenged to make a sketch of its workings do things like omit the chain, or connect the chain to both wheels, or draw the pedals outside the chain, but I don't believe I'd make any of those mistakes. On the other hand, if zipper technology were erased tomorrow, the world would be using buttons and hooks for a long time if they were relying on me to re-invent that mainstay of modern fashion. I know a flush toilet has something to do with siphon power, but that's about where I quit. Years of dusting the perfectly visible workings of the hammers in my piano have left me a bit vague about how all the levers fit together, though I do understand generally that the key tilts on a lever and that eventually translates that motion to a final hinged piece that strikes a string. All I really know about speedometers is that they know what fraction of a mile represents one revolution of my tire; years ago I was warned that putting the wrong size of tire on your car will make your speedometer mislead you about your speed. Helicopters and cylinder locks might as well be black magic.
So perhaps some education is in order, beginning with the onomatopoetic zzzzzzzipper.
The basic idea is a row of interlocking teeth that fit tight when in a straight line but loosely when bent into an arc. If the row is in a spiral shape, it generally is made of polyester, while "ladder-type" arrangements typically are made of metal. According to Wikipedia, "A special type of metal zipper is made from pre-formed wire, usually brass but sometimes other metals too. Only a few companies in the world have the technology." This is the sort of thing that sets one's conspiracy-detectors buzzing, but a helpful Forbes article explains how one Japanese firm came to dominate the zipper business by the early years of this century, including a charming anecdote about growing pains as an Asian company attempts to expand overseas:
Yoshida told the employees he sent abroad to melt into the local population as much as possible. In one incident an employee sent to Holland spent months studying Dutch so that he could make an opening day speech to his employees in their own language. After his speech the workers are reported to have said, “Wow, Japanese sure sounds a lot like Dutch.”Of course, no sooner had Japanese entrepreneurs sewed up the zipper market than China began to give them a run for their money.
Here are some do-it-yourself repair guides for a broken zipper, which should be easy to complete with our newfound understanding of the mysterious mechanism.
DNA molecules operate very much like a zipper. In fact, all enzymes employ the trick of opening up a clasp so that an interlocking shape can be inserted or removed before the clasp springs back.















