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Archaeologist May Have Found the First Protractor 78

If physicist Amelia Sparavigna is correct, in addition to frogs, lice, and locusts, Egyptian schoolchildren were also plagued with useless geometry instruments in their new notebooks at the beginning of every school year. A mysterious object was found in the architect Kha's tomb in 1906 and its function has remained the subject of debate ever since. Sparavigna is certain the object is actually the world's first protractor. From the article: "The key, she says, lies in the numbers encoded in the object's ornate decoration,(Pdf) which resembles a compass rose with 16 evenly spaced petals surrounded by a circular zigzag with 36 corners."
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Archaeologist May Have Found the First Protractor

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  • does this help solve the mystery of the Pittsburgh protractors? :)
    • Yes, duh. Everything involving human knowledge is implicitly prefaced with "known". Stating it is unnecessary.

      • I'm mostly referring to the headline stating it is the "first" but I would also argue that the "known" is not implicit.

        • Yes I know, "First known", and yes it is implied. It's always implied. "Biggest meat-eating dinosaur", "earliest hominid", "most spectacular bosoms", "fastest man on earth" -- everything regarding these statements has an implicit "known" qualifier.

          In cases where there is actually some reason to believe that there cannot possibly be something earlier, bigger, faster, etc -- i.e. cases where they are going beyond the implicit claim of "known" -- they will use some other qualifier. Like, "most massive star

  • Not useless (Score:5, Insightful)

    by JoshuaZ ( 1134087 ) on Monday August 01, 2011 @12:00PM (#36948472) Homepage
    Seriously, this is supposed to be news for nerds and the summary gets a gratuitous attack on protractors? They aren't useless now and they certainly weren't useless in the past. Before electronic systems, protractors were needed for all sorts of applications in architecture and engineering. In other areas, the way stars were carefully charted used protractor-like instruments. This last was particularly important in many ancient cultures because they relied on the stars to figure out just when to plant. Later, in the age of navigation, the sextant (again a protractor variant) was used to help accurately estimate latitude, a critical ability for sailors allowing the exploration and trade which eventually gave us the modern world. Moreover, aside from these applications, having children work with protractors helps them improve their ability to estimate things at a glance and improve their geometric intuition something that is important in daily life as well as all sorts of jobs, whether as things like carpenters or more academic jobs like engineers and physicists.
    • by mat catastrophe ( 105256 ) on Monday August 01, 2011 @12:07PM (#36948558) Homepage

      That's quite a passionate and protracted argument. I think you covered all the angles.

    • I think they were considered useless as in most math classes when students study Trig. they are taught to do the math and not measure it on a projector... (As values are not to scale) So in school it was a useless tool... However in real life where you do need to make things to scale they are quite useful... Even today. But if you were to use one in real life you are probably going to get something better then that $0.25 plastic protractor

      • Thanks, Yeah I never could figure out why they sell them in the school supply aisle. Every trig problem I had to solve went to great efforts to say angles are not accurate. In fact I think they would intentionally make the angles inaccurate to catch people. All those classes I would sit there wondering why do they even sell this or show us how to use them.

        I'd like to see a professional protractor.

        • by bmo ( 77928 )

          >I'd like to see a professional protractor.

          It's steel and it goes in my toolbox.

          There are those with vernier or electronic measurement so you can get resolution smaller than a degree. For measuring real-world things and for setting up machining and woodworking.


          • So you could almost use a protractor ownership to determine what kind of work a person does. I don't use a protractor, I deal with the ideal, with equations, with concepts. You on the other hand live in the real world and have to account for my screwups ;)
            "In theory there is no difference between theory and practice. In practice there is."

        • by fishbowl ( 7759 )

          >I'd like to see a professional protractor.

          We have dial indicators for calibrating machine tools (aircraft tolerances). This kind of tool doesn't look like a school supply protractor but it measures the same thing. There are also tools that use a laser strobe to measure stuff like jitter on rotating machine parts.

          In my VW toolbox I keep a homemade protractor. It's an aluminum one-legged arc that shows a few (experimentally derived) specific angles used for setting timing.

        • Every trig problem I had to solve went to great efforts to say angles are not accurate.

          On exam papers, in text books etc?

          Look at any properly made engineering drawing. Somewhere there should be an injunction "DO NOT SCALE", meaning "Do not measure anything on this paper and correct for scale ; if you think you need a measurement, and it is not written in the drawing, consult your supervisor."

          That applies to CAD-generated drawings as much as hand-drawn ones. The problem isn't in the drawing itself ; it's i

    • What's all that? I'm going to design video games for a living!
      *is ostensibly a grown man*

  • I read the fine pdf. Appears to be a degree system of measurement. Eat that, grad and radian fans...

    How she has ruled out a flower with 18-fold symmetry, or just random decorative stuff, is not described. I'd like to see a table of intervals vs measured degrees, I wonder how accurately it measures up.

    • I read the fine pdf.

      I read the image captions. Although it looks like english, it lacks a few important details, and even with those it would be gibberish. I refer to the caption that talks about the 16-fold symmetry (which it does not have) and the "18 corner" line, which they eventually admit actually has 36 corners.

      With that kind of writing, I didn't bother reading the body of the text.

      I'll save the point that the object lacks any reasonable means of use as a protractor for a different day. Oh, why not now. If there is a

      • This object could have just been the case for such a tool. (Which, in itself could be a neat find, but I doubt the object in the picture was the actual tool. The markings on the straight edge do not get further apart as you get to the edges and this is something you'd notice if it was used in the way described. (ie: With a plumb.)

        • This object could have just been the case for such a tool.

          TFA states that the object is a case, but for a balance, not a protractor. You can see the joint along the length of the body, but the hinges aren't illustrated. I'd guess leather, but not necessarily. And not important to the question at hand.

      • Although it looks like english, it lacks a few important details, and even with those it would be gibberish.

        Could you please translte you post into Italian. Your English is imperfect and confusing, and may actually be gibberish, and it would be so much more convenient for me if you wrote in Italian. Or Russian. Or French.

        The article is obviously written by someone working in a non-native tongue, English. So before you criticize, ask yourself if you could do any better.

        and the plumb line needs to pass throu

    • Appears to be a degree system of measurement. Eat that, grad and radian fans...

      I've heard that electrons can only spin in one of two directions. That means that they count in binary. Eat that, trinary, octal, decimal and hex fans ...
      Same argument ; same relevance. They're different tools for different jobs.

      Gradians (grads) were introduced to make artillery calculations simpler in the days when the calculations were done years before the gun was built and put into tables for use at the gun emplacement.

  • Multi-Tool (Score:4, Interesting)

    by jellomizer ( 103300 ) on Monday August 01, 2011 @12:22PM (#36948750)

    I would considered it multi-tool.

    You could use it a balance scale, a straight edge, a measuring unit, a protractor... Probably more. It would seem like a good tool for a Foreman to carry around and make sure the workers are getting things right or they need to be beaten more, heck by the look of it it could work as a nice club too.

    • Considering the WIDE variety of protractors and "squares" throughout history which perform more than one function, your explanation makes perfect sense. So does robust construction since job sites are rough on gear.

      Carpenters, ironworkers, and other tradesmen are still fond of the tools of their trade. No surprise one would be buried with them.

    • by jovius ( 974690 )

      The object is clearly made for accurate projectile shooting in the class room.

    • Perhaps more of a cestus instead of a club.

  • when you look at it from the Right Angle ...


  • by jovius ( 974690 ) on Monday August 01, 2011 @01:05PM (#36949260)

    How do we know that this isn't the world's second protractor?

    • The numbers on the top are obviously patent numbers. Since there are no serial numbers it's also, obviously, a prototype. No other device such as this could ever have been made.

  • Hidden within the article is that this is an empty case that might have held something. Looking at the outer shape, it could just as easily have been a cannon. If they wanted to be helpful, they shou'd have shown pictures of the opened case. There is also no scale for this object, but it appears fairly large. Why would an empty box be put into a tomb? It could be hollow as a way to make it lighter, instead of making it a box. It could have been a childs see-saw. I'd look for wear patterns on this, ubkess it

    • by Reziac ( 43301 ) *

      Looks to me like it's sitting on a sheet of quarter-inch plexiglass, so it's maybe 18 inches, ie. a bit over a cubit. I'd guess that the tool itself was exactly one cubit in length, making it multipurpose.

      And I don't know what the mystery is, when it's stated that the case was with a bunch of related tools and is of such an obvious shape for the tool. When I was in high school lo those several decades ago, we still used protractors of this exact same type in Geometry class; if I look in enough boxes, I prob

  • by Lord Grey ( 463613 ) on Monday August 01, 2011 @01:15PM (#36949404)

    I thought the archaeologist found Phssthpok [], a Pak Protector. That would have been news.

  • by Virtucon ( 127420 ) on Monday August 01, 2011 @01:16PM (#36949430)

    The worlds first pocket protector too? I'm also missing a "Dukes of Hazzard" lunchbox and Thermos so if the archaeologists see it, let me know.

  • If this is such a mystery, why don't they just go to Egypt and ask these schoolchildren? They know Egypt is a country right? "Egyptian schoolchildren" from which era?

  • ...or first Adult toy.
  • That's a toddler's's just leaning that way because that kid had no friends.

At work, the authority of a person is inversely proportional to the number of pens that person is carrying.