Peter S:

> 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)?

Countries could of course stipulate any solution they liked: Brownlie
uses the word "presumption" carefully in this section, to indicate
that in the absence of any other agreement, the "presumption"
pertains. It would be interesting to see if the original treaties
actually stipulated some action if the river moved, or if some
renegotiation took place afterwards. With reference to the potential
contrast between internal/international borders, Brownlie mentions
how internal borders are often less rigidly defined, because no
territory stands to be lost by a poor definition. Some African
countries still have rather poorly defined borders which the
inherited from internal administrative divisions from French West
Africa, or other large colonial units.

> 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.

Surely this is an example of border-moves-with-the-river, as Brownlie
describes? If the Chinese shift the flow pattern, and the border is
defined on the thalweg, the border shifts to their advantage.

Grant