One of the more important
aspects of Khor Rori that is overlooked by nearly all theorists, is the problem
facing a vessel moving out of a harbor, inlet, or narrow opening into the sea
with conflicting tides, currents, winds, and sea depth.
These three images show the problem with moving from a protected harbor
out into the sea. Top: What appears to be a smooth flow of water outward, is
(Middle) at least a rough and confusing tidal and current movement that makes
for breaching the ocean a very difficult thing, and (Bottom) at times can be
quite dangerous
The concept of bottom topography
plays an important role in a vessel breaching the ocean from an inlet, river,
or harbor where a channel exists. That is, for the ship to have been built, it
would have needed some type of harbor where the entrance to the sea was narrow
enough to restrict tidal and current fluctuations where the boat was moored.
The problem lies in that vessel then leaving the inlet and entering the sea. As
Nephi states it: “And it came to pass after we had all
gone down into the ship, and had taken with us our provisions and things which
had been commanded us, we did put forth into the sea and were driven forth
before the wind towards the promised land” (1 Nephi 18:8).
The problem any vessel has in leaving
protected harbor or inlet is to breach the current and waves upon entering the
sea. Even modern-day diesel driven vessels have problems. In the days of Lehi,
hitting swells like that could cause a broach, turning the vessel sideways to
the swell and even capsizing
In order to “put
forth into the sea,” the ship would have to move out of the protected harbor,
over the uneven topography that always lines areas where inlets, rivers, khors,
etc., empty into the sea.
First of all, probably one of the least
understood and anticipated influences on wave conditions is bottom topography.
Water depth has a major effect on waves, which will behave very differently
between shallow and deep water.
Waves do not merely affect the surface of a body of water.
The motion involved actually goes down fairly deep, around four times the
height of the waves. So if a wave is four foot, the water is being disturbed
down to a depth of about sixteen feet.
Thus, where the bottom suddenly rises up to near the
surface, such as the mouth of such an inlet, this can cause nasty sea
conditions—it is somewhat like wind flowing around tall buildings, and water
moving against a submerged plateau is going to "hump up" at that
point. And that “hump” causes a giant lift in the prow of the vessel and with
an inexperienced crew, could cause serious damage.
Not only does the underwater obstruction force a change in
water flow direction, but will cause increases in velocity and create nasty
eddies, which can create some of the most dangerous water conditions there
are—like rapids on a river that only a very skilled boatman can handle them. Such
places can be serenely placid at one moment, and deadly the next as the slack
tide or winds suddenly change. Consequently,
sailing from any location of a protected harbor or inlet out into the sea would
present problems for an inexperienced crew like that on Nephi’s ship.
What has been done in modern times, though not always
understood anciently, is the building of a breakwater system at such a harbor
in inlet area, to reduce the intensity of wave action in inshore waters and
thereby reduce the difficulty of entering the sea, though today, with diesel
engines, that is not the problem it once was. In fact, breakwater systems are generally
meant to break the force of waves, to an inlet, river entrance, or harbor as
well as to protect anchorage within the inlet or harbor.
Waves roll
in series, and every so often, a rogue or unusual wave will occur, at first
hidden among the swells and undistinguished to those who do not know what to
look for
It should be kept in mind that waves have a life cycle of
their own. As an example, with every 30th to 40th
wave comes a wave that is much larger than all the waves before it. Basically
the set of 4 waves merge and create a super wave. Recent studies have shown
that these rogue waves may be more common than oceanographers first thought, and they are
unpredictable, usually out to sea, but also along the coast and can create
undue damage. Even smaller forces can disrupt steerage, especially at critical
times such as moving out to sea, with the deeper the water, the greater the
change at such disruption.
One of the important things to keep in mind about the Sea of
Arabia along the south Arabian coast is that the sea has
depths that exceed 9,800 feet, and there are no islands in the middle. Deep
water reaches close to the bordering lands except in the northeast, off
Pakistan and India. To the southeast the Lakshadweep atolls along the
southwestern coast of India, form part of the submarine Maldive Ridge (1800
miles off Arabian coast), which extends farther south into the Indian Ocean
where it rises above the surface to form the atolls of the Maldives. On the
western side of the sea, 300 miles south off the Omani coast, the plateau
island of Socotra, about 70 miles long and with an area of about 1,400 square
miles, is an insular extension of the Horn of Africa, lying 160 miles east of
Cape Gwardafuy (Guardafui).
All of this leads to
the point that in this huge box-like area off the coast of Khor Rori is a very
deep sea of approximately 10,000 feet depth, where water is moving inland
toward the coast. When it reaches the area of rising land, it creates
undertoes, cross-currents, rising tides and tidal influences as well as other
navigational problems for a vessel entering the Sea of Arabia from an inland
khor or river.
In a wooden sailing ship of 600 B.C., the results of an
inexperienced crew in such waters would be disastrous.
However, one of the interesting factors of Khor Rori is the
natural breakwater effect provided by the two promontories along the entrance
to the inlet on either side of the khor. These two promontories or cliffs stand
about 100 feet high, blocking any winds that would effect the sails of the ship
as it passed, in addition, the extensions of them also block current eddies and
tidal changes along the coast, providing a “breakwater” arrangement out three
hundred to four hundred feet, more than three times the length of the boat and,
therefore, providing a smooth transition between khor and sea.
Yellow
Arrows: The Inqita’at Mirbat and Inqita’at Taqah promontories on either side of
the Khor Rori inlet mouth, provide a form of breakwater and (Blue Arrow) a safe
and easy entrance into the Ocean from the river (khor)
No other area along the coast provides such an easy egress
into the sea and is one of the major reasons the area was used by Roman ships
and traders for several centuries from
around 200 B.C. onward.
These
100-feet tall cliffs on either side of the entrance to the inlet act as breakwater
barriers and bring a tranquility to the waters entering and leaving the khor
It is interesting that these promontories provide a dissipation of energy and
relative calm water created in the lee of the breakwaters, thus allowing a
vessel of Nephi’s size to pass between and out into the ocean along a protected
path, requiring very little expertise from the crew.
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