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Thursday, 20 March 2014

Finding a lost mountain

The problem with searching for lost mountains is that they have probably been lost for a very good reason. In Australia, the early traditions was to slap the name of some wealthy and powerful patron or potential patron on each feature as it was added to the map.

Later, it became more common to actually ask the locals what the name of a place was, and to record that, but in the early days, the names given by savages were of less interest. So the largest river near Sydney is named the Hawkesbury after a worthless trimmer in the British government, and the main geological element seen around the city is now called the Hawkesbury sandstone, though Wiananatta shales and Narrabeen shales lie on either side of it.

If you are naming things after people, there are a few rules: you cannot name anything after yourself, though two colleagues can each claim a discovery and name their find after the other. The only problem is that sometimes the thing they see as a significant feature can be less so when you aren't trying to carry out a trigonometrical survey.

From page 157 of one of the books that
came from the search described here, my
Australian Backyard Explorer.
Triangles were very important in convict days. As every convict-oriented tourist attraction likes to remind us, just before a re-enactment that involves splatting somebody's back with tomato-soup-covered thongs, convicts were tied to an iron triangle before their lashing. Out in the bush, though, as people set out to map a new continent, triangles were central to the whole mapping thing, which commonly went by the name of triangulation.

The Greeks understood triangles, Mason and Dixon used them when they surveyed the Mason-Dixon line in the US, European surveyors understood it when they used triangulation to accurately plot lines up and down meridians at different latitudes so they could plot the shape of our globe, which is not quite the perfect sphere that the Greeks had assumed.

It works like this: if you have a carefully measured base line, you can get compass bearings on a prominent landmark from each end. Then if you draw a scale version of the baseline on your chart, you can locate that landmark in relation to the base line by completing the triangle. You just need to know the length of one side of the triangle, and the angles, which you get from the bearings, and that landmark is located. Repeat this with landmark after landmark, and you can begin to fill the map in, adding names as you go.

Now comes the beautiful part: if you are in a new place, like the junction of two streams, and if you can get bearings on any two known landmarks (though three will always be better), you can locate that point on the chart as well, and so accurately locate the river at that point. Then, as you work your way into new territory, new landmarks may be added to the map and given names.

Triangle by triangle, the chart builds up, each point being pinned down: and you don't just have the angles to play with, because you can also make an accurate measure of the distances between two mountains that are separated by a chasm, a burning desert, shark-infested seas or crocodile-ridden swamp. If you have one side measure, and the angles, you know the lengths of the other sides, and putting everything on the map is just simple trigonometry.

In short order, what began as a base line measured along a beach or across a plain, anywhere that is reasonably flat and open, is quickly parlayed into a chain of triangles linking named features that may extend over many degrees of latitude or longitude, or both.

And in time, the mountains and other features that were used at first as reference points, fade into the mists. Instead, surveyors will rely on a small number of accurately placed "trigonometrical survey stations", trig stations to the unwashed like me, poles with what appears from a distance to be a ball.

Far beneath the Hawkesbury sandstone, the Narrabeen shales and other rocks, the whole Sydney sedimentary basin sits on a bed of coal, the Permian coal measures, coal that comes above sea level in Sydney's south and north, and also approaches the surface of the ground in the west at Lithgow, past the mountains that hemmed in the colony.

The coal outcrops to the north were found in 1797, when Lieutenant Shortland entered the mouth of what was briefly known as "the coal river" in 1797, but he had the sense to dub it "Hunter's River", close to the modern name of Hunter River, celebrating the name of the then governor of the young colony of New South Wales, Captain John Hunter.

Newcastle is still a coal port.
It seems that even before official exploration, fishermen had found their way along the coast to the coal river and brought back lumps of coal to sell in Sydney, and there is evidence to suggest that boats were visiting the Hunter to cut timber (one branch of the river was already known as "the cedar arm").

Whatever the earlier history, it all became official in 1801 when a party that included Lt Colonel George Paterson, Ensign Francis Barallier, Surgeon John Harris and Lt James Grant, RN, arrived in His Majesty's Armed Surveying Vessell (sic) Lady Nelson, to survey the entrance to the river, and to assess the land for agricultural potential, as a source of timber, and as a source of coal.

The colony, based at Sydney, continued to grow, but the colonists were hemmed in until 1813 by a range of mountains to Sydney's west, which seemed to offer no way through. These mountains are made of the tough Hawkesbury sandstone, which also makes the insipid and sandy soil of Sydney, stuff unfit for a decent vegetable garden, incapable of supporting flocks and herds, deficient in trees suited for building work or minerals to be dug from the ground.

Even shell banks, suitable for making lime, were in short supply, so the group were expected to look into many things. (In fact, the first commercial export from the colony was a small cargo of 45 tons if coal, sent to the Cape of Good Hope in 1801.)

Before they left, all of them, except Barallier, who surveyed the area and made the chart, knew where their names would appear on the map, along with the name of the colony's governor King and King's wife, Ann, Paterson's wife Elizabeth, Harris' brother surgeon, William Balmain, and even a Mr. Edgerton, who was a friend of a friend of Grant. Today, all of those names have disappeared from the maps, even if they were once key features in the charting of the lower Hunter Valley.

I knew from Grant's journal that it was he who named "Mount Edgerton", shown on Barrallier's map as the "Egerton Hills", and Paterson had named Mount King and Mount Grant, while Barallier's map revealed Mount Harris and Mt Balmain, and a river branch called Paterson's River, which is now the upper reaches of the Hunter. Paterson's River has gone, and no modern map, shows any of them. A visit was needed, but the wilderness of 1801 is now a sprawling city of 400,000, and I rather feared that my mountains would be underneath suburbs.

I selected a finite set of targets: Mts Ann, Elizabeth, Grant and Harris, and called in at the Newcastle City Library. I had emailed them to say that I was coming, what I had read so far, and what I hoped to find, so I was met with several helpful books, but far more importantly, a copy of Barrallier's chart, an older-than-me Ordnance Survey map, and more modern maps were also on hand. It soon became clear that my lost mountains were beyond the city limits.

I expected the maps to be a little disappointing, because I thought they were Grant's work. Governor King, later in 1801, when Grant asked to be allowed to leave the colony, was rather dismissive of his skills: " . . . I should [have] been glad if your ability as a surveyor, or being able to determine the longitude of different places you might visit, was in any ways equal to your ability as an officer and a seaman."

Instead, the chart was the work of that supposed paragon of cartographic virtue, Ensign Barallier, and I began to understand why Barallier's chart of his wanderings in the Blue Mountains has been impossible to reconcile with today's landscape. In short, I soon realised that Barallier's chart of Coal Harbour was not a close match for either present-day charts or reality. Barallier wasn't as good as people had thought.

Whatever the man's deficiencies as a cartographer, the layout was more or less right, and as I looked at the windings of the river on the different maps, I began to link up some common features, and to spot some possibilities. Working with maps on different scales, and with Barallier's eccentric rotation of the map to put west at the top, it helped to have some clues left by one of the librarians, in the form of an indication that "Mount Grant is below Clarencetown".

That gave me Mount Grant as a small prominence, 3 km SE of the town, far from any roads, on the thoroughly modern Clarencetown CMA sheet. Working systematically, triangulating from one map to another, one prominence to another, I pinned the assorted hills down, more or less, in a hypothetical way, perhaps. One high point stood out as worthy of attention: it was near a road, just after it crossed a railway line, and it had a name.

There was a trig station shown on it, so I knew it would be prominent, even if it now bore the dismissive name Comerford's Hill. Better still, there was another marked trig station near the hamlet of Largs that appeared to match another of my mountains, so I headed for the area outside the rural city of Maitland.

Then, my potential Largs mountain (Mt Edgerton) proving elusive, I headed for the second target, and by asking around for the Rosebrook road, found myself crossing a bridge where a side road was labelled "Mount Harris Drive".

Did I mention that my note-taking methods are a bit chaotic? I write everything down as I spot it, so I can always go back and reconstruct the processes, so I wasn't sure which mountain this was supposed to be. There is another Mount Harris in New South Wales, named in 1817, but that is also rare on maps, and a target for a later search, so I was delighted to find this one.
The Hunter River, seen from what is now Comerford's Hill.

The sign said Mount Harris, so Mount Harris it was. I should, perhaps, have mentioned that the mountains in this area are vertically challenged to a marked degree. This may help to explain why this Mount had been downgraded to a mere Hill, but at least it was small enough to drive around.

Comerford's Hill must once have been a farm, now it is several swanky hobby farms behind an unwelcoming gate across a muddy track, so I went up the gravelled Mount Harris Drive instead. This took me past a water reservoir with a trig station on top, but there was a higher rise, a little further on, so I drove further, and got out.

Being unchallenged (I was rather hoping somebody would come out to question me, so I could question them in turn), I walked to the crest, and found that I was looking down on the Hunter, Paterson's River to Barallier. I cannot reconcile this with the map, but Grant's description of it as having "extensive and picturesque" views tallies with what I saw (except that the locals have created a rubbish dump at the highest point).

Of course, it was only later, when I realised that Mount Harris is quite a long way from there, and that this hummock was in fact Mount Ann, that I realised I had another serial geographical victim on my hands, besides Dr Harris (and Barallier, whose name appears on no map that I know of). You see, in an effort to curry favour with Governor King, Lieutenant Grant had, five months earlier, named "Ann's Island" in Jervis Bay, unaware that it had already been dubbed "Bowen's Island", the name it bears today on the charts.
The other Mt Harris on the Macquarie River is also unimpressive.

So in sum, I have found just one of the lost mountains. lurking where it always was, but under two false names. I need more maps, more research time, and another 500 km of driving, in order to sort the question.

When I set off to pursue John Oxley's travels, when he named the 1817 Mount Harris, I pursued it. This one is 46 metres above sea level (I wasn't joking about vertically challenged!), but it is still findable.

It is better to travel hopefully than to arrive, but plain travelling isn't all that bad, either.

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