A logical and straightforward solution. But what about all these
cases where the boundary does follow the old river course? To name
but a few cases: the boundaries along the Mississippi, the Maas river
just south of Maastricht (benl boundary) (on Eef Berns' site I found
out that there is a plan to rectify the border here), the old czsk
boundary in the Morava (prior to the simplification of the border,
for which a new treaty was necessary!), etc. Was there no mention of
the thalweg in these treaties? Or is Brownlie's solution a more
recent one (most African boundaries aren't that old)?
The problem of the two islands at the Amur/Ussuri confluence springs
to mind, where the Russians accuse the Chinese of attempting to
change the main course of the river, and thus the main thalweg, only
to get their hands on the islands. But for this stretch of river, the
Russians and Chinese agreed to disagree for the time being, so the
more modern approach might be used.
I am tempted to say Brownlie's solution is the more modern one, and
the "fixed boundary" solution the older one. After all, at least in
Europe, in the past, lots of rivers meandered more than nowadays, so
the resulting loss/gain of territory could have been quite
considerable in the old days. I don't know when the "thalweg"
definition came into use, but it might have something to do with it.
In the Netherlands, after the great flood of 1421, an enormous area
was flooded and remained a sort of internal sea long afterwards. But
seigniorial boundaries remained largely unchanged, so that one
seigneurie could consist of two pieces of land that were a big
distance apart. It is not quite the same as a shifting river, but
somehow related, I think.
The provincial boundary of North Brabant and Gelderland along the
river Maas used to make quite some detours, following the old
riverbed. This boundary was rectified, I suspect sometime in
the 'fifties.
Or is the difference in approach not related to a boundary being old
or new, but being international or internal? The problem of
losing/gaining territory is more acute when it is an international
one. But I remember that I once asked my American uncle, who had
given me a map of Arkansas, why that border was so stubborn not to
follow the main course of the river, that he answered me: "O, but
there are boundary disputes over the border sometimes as well!" I
imagine a dispute between US states is much more serious than a
dispute between provinces in the Netherlands...
By the way: the US-Mexican "hinge" solution is a great one. I wonder
whether there are more of these hinges in the world. There must be.
Peter S.
--- In BoundaryPoint@y..., granthutchison@c... wrote:
> A while back Peter S asked for authoritative opinion on whether a
boundary
> defined by a river would move when the river course shifted, or
stay along
> the historical track. I found one example of a boundary that did
move with
> the river - the US/Mexico border on the Rio Grande - but couldn't
say if this
> was a feature of a general principle or a specific agreement.
> Now I think I've found the general authoritative statement.
Brownlie, in his
> introduction to African Boundaries, has a section call Some
Technical
> Problems. In it he states: "A related question is whether changes
in the
> breadth or course of the river involve changes in the boundary. The
> presumption in the case of reference to the line of a river, or its
thalweg,
> is that the boundary follows the feature."
>
> Grant