It had long been a theory that a liquid did not retain its shape when removed from its container. However, scientists were forced to change that theory after observing the photographs shown here. The photographs show that the water in the balloon retained its balloon shape for 12 to 13 millionths of a second after the balloon had been burst by a dart.
The first time I saw that caption and the photographs, I was reminded of a wonderful figure of speech coined by the famous physicist Wolfgang Pauli. When he was asked to comment on a scientific paper that had been submitted for publication, Pauli said: "This isn't right. This isn't even wrong."
What Pauli meant was that the paper had no connection with scientific reality, and that trying to correct it would be pointless. The only rational thing to do would be to start over from scratch.
The same applies to Prentice Hall's illustration. The notions set forth in the caption are so completely divorced from reality that the caption isn't even wrong.
"It had long been a theory that a liquid did not retain its shape when removed from its container," Prentice Hall's writers say. In reality, no such theory has ever existed. The writers have invented an imaginary "theory" that is the inverse of the well known concept that a liquid conforms to the shape of its container. That concept, however, is a part of the definition of a liquid -- it is not a matter of "theory" at all. And even as a definition, the writers' statement is ridiculous: No one has ever defined a liquid as something that does not retain its shape when removed from its container.
The writers next declare that "scientists were forced to change that theory after observing the photographs shown here." In reality, the photos did not induce scientists to change any theory, any definition, or anything else. The photos don't show anything that was unexpected -- and rather than impugning the concept that a liquid accepts the shape of its container, these photos confirm it. The first photo shows that a mass of water inside a balloon did indeed conform to the shape of the balloon, and the second shows that the water even held that shape for about 13 microseconds after the balloon disintegrated. (In 13 microseconds, the water hadn't had time to move.)
Prentice Hall's absurd caption is all the worse because the writers have missed an opportunity to tell something important. If I had been in their place, I would have written a caption like this:
Science requires observations of the world around us. Sometimes we can employ instruments to enable us to see things that are so small or so fast that we cannot see them with our eyes alone. We cannot, for example, see what happens at the instant when a water-filled balloon is pierced by a sharp object -- but we can use a high-speed camera to take photos that show how the balloon and its contents behave. Here are two such photographs. They show that the water retains the shape of the balloon, for a few millionths of a second, after the balloon disintegrates.
Who makes up the stuff that Prentice Hall puts in its "science" books. Did anyone at Prentice Hall actually believe that the water-balloon caption made any sense or had anything to do with science? Did the caption's foolishness actually escape the notice of all the "reviewers" listed in all those versions of Prentice Hall Exploring Physical Science and The Nature of Science? Or did Prentice Hall's editors just not care enough to replace it?
Leonard Tramiel, of Palo Alto, California, is a computer programmer and an amateur astronomer. He holds a doctorate in astrophysics from Columbia University. He teaches astronomy in local schools, as a volunteer, under the auspices of Project Astro, sponsored by the Astronomical Society of the Pacific.
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