The 141st meridian east is an interesting meridian.

It approximates the border between Papua New Guinea and the Indonesian province of West Papua. However, there is a slight interruption at the intersection of the Fly River.

Map showing the border between Indonesia and Papua New Guinea. By Plucas58 – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=42846276

141 East also approximates the eastern border of South Australia, where South Australia borders with New South Wales and Victoria. However, south of the triangular border between South Australia, New South Wales and Victoria, the border shifts very slightly west of the 141 E meridian.

Map: OpenStreetMap contributors, CC BY 4.0 https://creativecommons.org/licenses/by/4.0, via Wikimedia Commons

The border in both instances appears to have been where it is because of British decisions. In this post, I am going try to find why they chose 141 E.

Brief Historical Background of these borders

1836: The province of South Australia was carved out in 1836. This is the first use of 141 E. This meridian was later used in 1859 as the western border of Queensland when the Colony Queensland was first established. For a more full understanding, see this wikipedia article for the full territorial evolution of the states.

1883: In the case of the Papua New Guinea/Indonesia border, 141E was initially chosen by the police magistrate of Queensland during an attempt to annex the eastern half of Papua. The attempt seems to have initially failed as it did not get the rubber stamp from the British crown. But then shortly after, Germany annexed the northern half of that portion, ie the north east quarter of the island. Then the British immediately stepped in and annexed the south east quarter of the island. This all happened in 1883 and I have blogged about it here. It was obviously co-ordinated between Germany and England, otherwise Germany would have annexed the entire eastern-half and not just the north-eastern quarter.

Why 141 East?

Why 141 East, and not – say – 140 which is a more round number? 141 East seems to have been plucked from thin air.

Well I think it is to do with (like many unexplained colonial executive decisions) the doctrines of discovery.

Let’s look at the island Papua/New Guinea/Irian itself. The name New Guinea was given by a Spanish explorer (and probably “first discoverer”) Inigo Ortiz de Retez. He claimed possession of the land from the mouth of the Mamberamo River. This is a massive river system, the third largest by discharge in Oceana according to wikipedia. Under the Doctrines of Discovery, if a discoverer claims the mouth of the River – he claims the river catchment.

The headwaters of this river is in very thick jungle. So it would have been very difficult for any Europeans to precicely survey the exact eastern-most point of the catchment. But 141 degrees east is actually pretty darn close to the eastern-most meridian in which the Mamberamo River catchment falls.

I don’t have a actual map of the Mamberamo River catchment, so I quickly mocked this Google earth screenshot up. You can look on Google maps or Google earth and follow the river upstream with your mouse and eyeballs. The catchment seems to sneak over the border at one point, but the eastern-most point of the catchment is pretty damn close to 141 East (marked here in yellow as the Indonesia/PNG border).

Doctrines of Discovery

So let’s look at this in terms of the Doctrines of Discovery.

The Spanish claimed and planted the flag at the mouth of the Mamberamo River in 1545. That puts the catchment under Spanish First Discovery, and also makes it a single, contiguous territory (at least until it is challenged).

The Portuguese probably had contact with the island of New Guinea before the Dutch moved in, but it seems this contact was limited to the west and outside of the Mamberamo catchment. The Dutch had treaties with the Sultanate of Tidore, who claimed to have coastal parts of New Guinea (including in the catchment) as something akin to vassal state territory.

As the Spanish had initially claimed up to 141 degrees east (even though they were not aware of the extent of their claim), any subsequent european claim encompassing parts of the river catchment would also extend to 141 east. This would include the Dutch/Tidore treaty, so in other words, the Dutch have claim of the Mamberamo catchment because of their treaties with Tidore.

So before the British (or should I say, Queensland) came along, no one had actually claimed, settled or treatied with natives east of the Mamberamo River catchment. Since the Spanish claimed discovery a very long time ago in 1545, and the Dutch never moved further east, it could be said that territory east of Mamberamo River catchment is ripe for the taking.

All up, this makes 141 east a decent candidate border for the eastern most meridian of the entire Dutch East Indies territory itself. The Dutch didn’t have any establishments east of that line. The most eastern part of their effective administration in the region was Aru Islands, well to the west of 141E.

This is probably why South Australia was established in the way that it was. South Australia was a test. It was like a provocation for the Dutch to react and challenge inpingment on their side of the 141 East meridian. This meridian was also used for the border of the Colony of Queensland for the same reason.

Also note, the western border of the Province of South Australia was initially set at 132 east – not at the Western Australia border. This left an awkward gap on the map. When Bremer stood on Coburg peninsular (near Darwin in the north) and annexed a large chunk of New Holland just after the Anglo-Dutch treaty of 1824, he stood less than 20km east of this 132 East meridian.

Map: The awkward gap west of South Australia (ignore the captions/text, it is unrelated…). By User:Golbez – Own work, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=63611588

The northern border of South Australia was set at 26 degrees south. At this same latitude on the east coast is an area which Matthew Flinders explored in high detail (Hervey’s Bay), and I believe it is because 26 degrees south lies in-between the two following latitudes: 1. The half-way latitude between Cape York and South West Cape in Tasmania (27°09’59S) and 2. the half-way latitude between Cape York and Wilsons Prom (24°54’42). Setting SA’s border at 26 South is a hedge betting strategy for drawing a north-south, British-Dutch border.

So next thing…. what’s up with the anomolies in the borders?

The so-called Survey Error in Australia state borders

First a map to get started… Here is a map showing the 141 E meridian in red, a very roughly drawn Mamberano River catchment in white, and the Murry Darling Basin in purple-ish.

So if the Dutch East Indies eastern boundary is at 141 degrees east, there is a problem here for the British. Because the mouth of the Murray Darling is actually on the Dutch side of the line. So technically, that might mean that the entire Murray Darling catchment is part of the Dutch East Indies.

Now let’s look at the so-called survey error again;

Map: OpenStreetMap contributors, CC BY 4.0 https://creativecommons.org/licenses/by/4.0, via Wikimedia Commons

It is at the Murray Darling that the “survey error” that the anomoly begins.

I think this is no survey mistake, but deliberate.

The main reason for this is to bolster the British claim of the pocket of territory that lies to the south and outside of the Murray Darling catchment – ie. roughly half of Victoria – the parts of Victoria south of the top ridgeline of the Victorian alps including Melbourne, plus a small corner of South Australia (including Mt Gambier up to Tintinara).

This is because the British can then argue that the western border of Victoria has nothing to do with 141E, but is simply an well established administrative boundary that runs through the British pocket of territory south of the Murray Darling catchment.

This “survey error” also helps a little in bolstering the claim of the Murray Darling catchment itself – by having part of the border running along the river makes the river an integral part of the border, and proves the British “know” the river and have surveryed it. (Later on the British claim on the Murray Darling catchment is further bolstered with the drawing up of the QLD/NSW border at misplaced “Point Danger”, but that’s another story that I touched on in this linked post)

With this “error” – upon Dutch challenge of the establishment of the Province of South Australia, a new (potential) international border between British colonies and the Dutch East Indies would be much more likely to run along 141 East down to near Broken Hill, where it would turn westward and follow the northern border of the Murray Darling catchment to somewhere near Adelaide. This is much preferable for the British than 1. losing the entire Murray Darling catchment to the Dutch, or 2. having the 141 east line go directly south to the south coast.

Note also

1. That Adelaide – the capital of the Province of South Australia was situated just outside to the west of the Murray Darling catchment, it is seperated from the catchment only by the Adelaide hills. This is kinda convenient also, because in case of challenge, the British could argue that they are already settled and established west of the catchment.

2. Flinders’ encounter with the French explorer Baudin in 1802 actually happened right next to the mouth of the Murray Darling, even though at the time officially Europeans supposedly didn’t know where the river mouth was. Kind of an amazing coincidence that the British and French were BOTH at such an important strategic location at the same time. I’m pretty sure Flinders knew the mouth was there, and that is also why he was scoping out the Flinders Ranges for suitable sites for a coastal settlement west of the Murray Darling catchment. He even made a rare excursion on foot to the top of the ranges, probably in the hope of seeing a massive river on the other side. Maybe the French knew about the mouth as well, I suspect they had British informants (double agents) passing them intel which is why Baudin was also there.

And the little zig-zag in PNG/Indonesia border….

I’m not exacly sure yet where the zig-zag at the Fly River came from or when it came about, but here’s my guess.

Note that the zig-zag is definitely well to the south of the Mamberamo catchment and on the British (south) side and not the German (north) side. So it would have been a British creation. The Germans didn’t care, whereas the British had high stakes due to territorial claims on mainland Australia.

I am guessing that the British re-jigged the border at some stage, and gave up a little bit of high jungle so they can later argue that the border has nothing to do with 141 east. This distances them from the doctrines of discovery and the contention with the Dutch, and makes the border simply of an administrative nature.

• sorry if my spelling/typos is bad here, I’m on German spellcheck so the whole post is red quiggly lines 😀