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In פרשת בשלח 16:14, it says --

The layer of dew went up, and behold, on the surface of the desert, a fine, bare [substance] as fine as frost on the ground.

On that verse, Rashi says (translated from here)

When the sun would shine, the dew upon the manna would rise toward the sun, as it is natural for dew to rise toward the sun. [This is similar to] even if you fill an egg shell with dew, close up its opening, and place it in the sun, it [the egg shell] will rise by itself in the air

Is this actually true scientifically? Has anyone ever tried or seen this?

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@DoubleAA Sounds like a fun question....but probably a better fit on Physics, no? – Shokhet Jul 4 '14 at 3:56
Also, @DoubleAA, does that Rashi have to mean the eggshell, and not the dew itself in the form of steam? – Shokhet Jul 4 '14 at 4:01
@Shokhet He says היא whereas טל is masculine, I think. – Double AA Jul 4 '14 at 4:14
@Shokhet כַּאֲשֶׁר יִפֹּל הַטַּל עַל-הָאֲדָמָה (Sh'mu'el II 17:12). However, Rashi may have been referring to שכבת הטל, even though he omitted the word שכבת. That's feminine. – Fred Jul 4 '14 at 5:06
Someone on the internet claims to have conducted this experiment multiple times, and says that one time the egg rose a few centimeters. – Fred Jul 4 '14 at 5:12

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