"He has made the two seas to flow freely (so that) they meet together:Between them is a barrier which they cannot pass. " (Quran, 55:19-20)
The Mediterranean Sea and Atlantic Ocean meet each other at the Strait of Gibraltar. One of the properties of these two seas that has only recently been discovered is related in a verse of the Quran as follows:
"He has made the two seas to flow freely (so that) they meet together: Between them is a barrier which they cannot pass. " (Quran: 55/19-20)
This property of the seas, that is, that they meet and yet do not intermix, has only very recently been discovered by oceanographers. Because of the physical force called "surface tension," the waters of neighbouring seas do not mix. Caused by the difference in the density of their waters, surface tension prevents them from mingling with one another, just as if a thin wall were between them.
It is interesting that, during a period when there was little knowledge of physics, and of surface tension, or oceanography, this truth was revealed in the Quran.
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