# burning the oil in our menorah - how does it work?

**URL:** <https://boards.straightdope.com/t/burning-the-oil-in-our-menorah-how-does-it-work/607566>\
**Category:** Factual Questions\
**Created:** [December 27, 2011, 9:19pm UTC](https://boards.straightdope.com/t/burning-the-oil-in-our-menorah-how-does-it-work/607566 "2011-12-27T21:19:36Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Shinna\_Minna\_Ma](https://avatars.discourse-cdn.com/v4/letter/s/f08c70/32.png) [@Shinna\_Minna\_Ma](https://boards.straightdope.com/u/Shinna_Minna_Ma)\
**Post date:** [December 27, 2011, 9:19pm UTC](https://boards.straightdope.com/t/burning-the-oil-in-our-menorah-how-does-it-work/607566/1 "2011-12-27T21:19:36Z")

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So now that I’ve finished lighting eight nights of oil in our menorah, can anyone explain the chemistry behind how it works? How does lighting the top of the wick draw the oil up to burn?

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**Author:** ![aceplace57](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aceplace57/32/3500_2.png) [@aceplace57](https://boards.straightdope.com/u/aceplace57)\
**Post date:** [December 27, 2011, 9:26pm UTC](https://boards.straightdope.com/t/burning-the-oil-in-our-menorah-how-does-it-work/607566/2 "2011-12-27T21:26:45Z")

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Capillary action -

> **[Capillary action](https://en.wikipedia.org/wiki/Capillary_action)**
>
> Capillary action (sometimes called capillarity, capillary motion, capillary rise, capillary effect, or wicking) is the process of a liquid flowing in a narrow space without the assistance of external forces like gravity.
> The effect can be seen in the drawing up of liquids between the hairs of a paint-brush, in a thin tube such as a straw, in porous materials such as paper and plaster, in some non-porous materials such as clay and liquefied carbon fiber, or in a biological cell.
> It occurs becaus...

> [@](#):
>
> Capillary action, or capilarity, is the ability of a liquid to flow against gravity where liquid spontaneously rise in a narrow space such as between the hairs of a paint-brush, in a thin tube, in porous material such as paper, in some non-porous materials such as liquified carbon fiber, or in a cell. This effect can cause liquids to flow against the force of gravity, sun or the magnetic field induction. It occurs because of inter-molecular attractive forces between the liquid and solid surrounding surface; If the diameter of the tube is sufficiently small, then the combination of surface tension (which is caused by cohesion within the liquid) and force of adhesion between the liquid and container act to lift the liquid.[1]

[http://www.ehow.com/how-does\_5142658\_oil-lamps-work.html](http://www.ehow.com/how-does_5142658_oil-lamps-work.html)

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**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\
**Post date:** [December 27, 2011, 9:51pm UTC](https://boards.straightdope.com/t/burning-the-oil-in-our-menorah-how-does-it-work/607566/3 "2011-12-27T21:51:53Z")

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> [@Shinna\_Minna\_Ma](#):
>
> So now that I’ve finished lighting eight nights of oil in our menorah, can anyone explain the chemistry behind how it works? How does lighting the top of the wick draw the oil up to burn?

Capillary action will draw the oil from one end of the wick to the other, saturating the entire wick regardless of whether it’s lit or not. When you light one end of the wick, the oil there vaporizes and burns, freeing up pore space for the oil in the rest of the wick to move into those empty pores, continuing the process.