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From: George Huxtable (no email)
Date: Thu Sep 16 2004 - 20:11:43 EDT
Alex Eremenko asked-
>Do the following islands exist (or DID they exist in XIX century?):
>Tabor (a.k.a. Maria Teresa) and
>Ernest Leguve Reef?
>
>According to Jules Verne ("Children of Capitan Grant" and
>"Misterious Island"), the island of Tabor (Maria Teresa in French
>maps) is on the parallel 37 degrees S, somewhere West of New Zealand.
>The main action of "Misterious Island" takes place on the
>"Lincoln Island", as Jules Verne's characters call it, about 100
>miles from Tabor island.
>
>When I read these novels in my childhood,
>I checked with the World Atlas
>(published in Soviet Union
>in 1959), and both islands were exactly where Jules Verne placed
>them. They were called Maria Teresa Reef and Ernest Leguve Reef.
>(I cannot be 100% sure in the spelling of these names: I've
>seen them written only in Russian!)
>
>However, in the later years, using all modern US maps I could find,
>and the Internet, I could never find these islands again.
>Unfortunately I do not possess this old Russian atlas anymore.
>Can anybody help me to solve this riddle?
>I can provide the precise coordinates from Jules Verne.
>
>One conjecture is that the islands existed in XIX century but
>then disappeared as a result of the motion of the ocean floor...
>
>Or did Jules Verne invent them, and Russian map makers placed them
>according to Jules Verne? :-)
===============
Response from George-
First, I would like to welcome Alex Eremenko to our group; especially if he
is turned on by the idea of lunar distances.
I have two oldish atlases, one the Oxford Atlas of 1956, the other the
5-volume Times Atlas of 1957. In both of these, the map of the Pacific
shows "Maria Theresa Reef" at roughly 37deg South, 152deg West, with
"Ernest Legouve Reef" a couple of hundred miles further North. So it was
not then (in the 1950's) an island but a reef, and not (as Alex suggested)
West of New Zealand, but far to the East. So is this the locality that Alex
remembers from his old Russian Atlas? The 37-degree latitude corresponds.
What Alex needs to look at is a modern navigational chart (and perhaps an
early chart also) of that part of the Pacific. A chart, rather than a map
in an atlas, will distinguish carefully between an island, a reef, and a
shoal.
But let me add an indistinct recollection, for what it's worth. For years,
my collection of 70-odd Admiralty Charts has been kept corrected up-to-date
by my wife, from weekly Admiralty Notices to Mariners. These cover chart
corrections for the whole World, although only a small corner of it is of
interest to me.
About 15 or 20 years ago, my wife pointed out a curious chart-correction,
referring to "Maria Theresa Shoal". The correction was to delete Maria
Theresa Shoal from its charted location, and replace it elsewhere. Such
changes are common, usually noting a bit of fine-tuning in the positioning,
perhaps by a mile, or just a fraction. This one was different, shifting the
position of Maria Theresa Shoal by hundreds (or it may even have been
thousands) of miles. For most corrections, the Admiraly usually quotes the
authority responsible for initiating the change, and for this one it quoted
something like "re-evaluation of old reported data".
I can only apologise for my failure to recall the details with any more
precision than that. I have no idea, now, whether the initial or final
positions corresponded to those atlas coordinates referred to above.
At the time, I presumed that someone had been going through the log or
journal of the explorer or navigator who long-ago reported the existence of
the shoal, and perhaps uncovered some error in analysis, or
misunderstanding, and informed the Admiralty of his findings. And then,
presumably, the Admiralty had, with some embarrassment, shifted the charted
position of the shoal accordingly. It's easy for such things to happen. For
example, many circumnavigators tended to note their longitudes from 0deg to
360 deg, Westward or Eastward, depending on which way they were going round
the world, rather than making a switch at 180 as we would today.
Coral reefs are built up by accumulation of coral species over a sea bottom
that is gradually sinking with respect to sea level. It depends on whether
the coral growth can keep up with the rate of sinking: if not, what is an
island (always above water) in one era can become a reef (sometimes above
water) in another, and a shoal (hazardously below water) in the next. And
then, it depends on the mapmaker which of these qualify to be marked and
named, in mid ocean. A feature which is noted on one map may be omitted
from another.
However, don't think I am claiming to have any special knowledge of the
geography or ecology or mapping of the South Pacific.
By the way, I think the technical term for such an island or feature, the
position or even existence of which is uncertain, is a "vigia".
George.
================================================================
contact George Huxtable by email at , by phone at
01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
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