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I found this picture.

old

An old mathematician has devised this tool. It is about conic sections.

What does it do? I can't figure out.

Maybe only Arab users can answer this question. The script is written in Arabic.

I understand some of the words such as "برکار" which means compass. And "تام" meaning universal; complete.

It seems this is designed to draw any conic section. But is that possible?

From the translation of the text in the picture, it turned out to be a universal conic section drawer compass.

Now my question is how does it do that?

the most relevant place to ask this, I think, must be here. Because here may be some people who have seen this tool once.

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    You may want to take a look at the two pictures at the bottom of [this page](https://php.math.unifi.it/archimede/archimede_NEW_inglese/curve/guida/paginaindice.php?id=2&idd=1). This question sounds more relevant to the [history of math and science](http://hsm.stackexchange.com). Anyway, I found the [persian article](https://fa.wikipedia.org/wiki/%D8%A7%D8%A8%D9%88%D8%B3%D9%87%D9%84_%D8%A8%DB%8C%DA%98%D9%86_%DA%A9%D9%88%D9%87%DB%8C) to be more informative (Yes, I could read it) – 2017-01-05
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    @polfosol The two pictures are very small. And the Wikipedia article doesn't talk about the principle upon which this apparatus was made. I think understanding the way this thing works is more related to math rather than history of math, compatriot! – 2017-01-05

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This is a compass, a device for drawing circles by rotating a pencil. The marks measure the angle of the compass (and thus the radius of the circle). The original image can be found on Wikimedia commons.

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    Just a simple compass? – 2017-01-05
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    Probably, that's what the description says, and I don't see any way to change the angle evenly while drawing, so it can likely only draw circles. – 2017-01-05
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    Why two protractors then? – 2017-01-05
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    [Wikipedia presents it](https://en.wikipedia.org/wiki/Ab%C5%AB_Sahl_al-Q%C5%ABh%C4%AB) as being a "perfect compass to draw conic sections". Since an ordinary compass can't draw conic sections other than a circle, there must be more to it. References 6 through 10 in the Wikipedia article seem to lead to more detailed descriptions of it. @AHB. – 2017-01-05
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    My bad, the leg can indeed be moved while drawing. https://hal.archives-ouvertes.fr/hal-00658217/en – 2017-01-05