WHEN the fleeing Israelites hotly pursued by Pharaoh and his troops, were making their escape from Egypt, they found themselves at one point trapped on the western shores of the Red Sea. God, however, saw them right: "All that night the Lord drove back the sea with a strong east wind and turned it into dry land and the waters were divided and the Israelites went through the sea on dry ground, with a wall of water on their right and on their left." When the fugitives had gone across, "the waters returned, and covered the chariots and horsemen" of the Egyptians in their wake.
Scientists, in their idle moments, like to imagine possible natural solutions to such biblical conundrums. In the case of the parting of the Red Sea described in Exodus, they have come up with three ways in which the Lord might have engineered the miracle.
One suggestion is that the parting may have been simply a mirage. Perhaps the Israelites did not cross the Red Sea at all, but took a more northerly route across the Nile Delta. The hot sun shining on the sandy soil could produce an appearance of shimmering "wetness", similar to that often seen here on a tarmac road in summer time: perhaps Moses simply led his people through an illusion of water, which appeared to part in ont of them and to close up gain behind. But this does the explain what happened to poor Egyptians.
Another theory is that the parting of the Red Sea may have been caused by an unusually strong and persistent wind. Wind blowing over a body of water for an extended period tends to pile the water up before it like a ridge of soil before a bulldozer - a phenomenon sometimes evident "in Cork when a spring tide combines with onshore winds to cause local flooding. This argument puts the crossing at the northern edge of the Gulf of Suez, where the basin of the sea is narrow, long and shallow.
Computer simulations suggest that a wind of 40 miles per hour blowing there for 10 to 12 hours would cause the shoreline to recede by about a mile, and the level of the sea to drop enough to allow the Israelites to cross on foot. A sudden drop in wind, or change in its direction, would then bring the waters flooding back on top of Pharaoh.
The third possible explanation is that the drowning of the Egyptians was caused by a tsunami - a tidal wave associated with a volcanic eruption somewhere under water to the south, and propagated northwards towards the Gulf of Suez.