Apple maps

by Les

Mildura

Mildura, Victoria, Australia

There were news reports recently of Apple Maps giving an inaccurate location for the town of Mildura in Victoria, Australia.

Instead of arriving at the pleasant river town shown above, motorists relying on directions from Apple’s iOS6 Maps arrived at a location in the semi-desert 40 miles south-southwest of the town. I don’t have a photo of the area motorists were sent to, but I do have a photo taken in a similar area nearby.

Morkalla, Victoria

The abandoned railway at Morkalla, west-southwest from Mildura.

The error is shown in this map, linked from AppleInsider:

This area of Victoria (where Apple thinks Mildura is) is within the Murray-Sunset National Park (which is also placed incorrectly in the Apple map).

Sunset Country is a term used to describe this part of northwestern Victoria. It is  semi-desert, with red east-west sand ridges covered with mallee scrub. The tracks through the park are suitable for off-road vehicles only.  If  Goyder’s Line extended east into Victoria, this part of the state would be outside of it, in the area unsuitable for agriculture.

The western boundary of Victoria has some interesting history. The colony of South Australia was established at Adelaide  in 1835, and legally limited by the British government to the area west of 141° east longitude. Land east of this longitude was in New South Wales, and governed from Sydney. However, the technology to establish this longitude on the ground was quite cumbersome and expensive in those days, and  in the early years of settlement by Europeans the problem was ignored.

But by 1845 disputes between squatters moving west from Melbourne and those moving east along the coast from Adelaide made a definition of the boundary between South Australia and New South Wales urgent. Which colony had  the right to settle disputes about a particular piece of land?

In November 1846 the Colonial Secretary’s Office in London directed surveyor Henry Wade to proceed from Sydney to the disputed territory to define a Boundary for Police Purposes between the two colonies. Wade started on this project at the coast in March, 1847. By December Wade was still 155 miles south of the  Murray River, and the expedition collapsed, due to extreme hot weather and drought. The South Australian government and the New South Wales government agreed that the line defined by Wade was the legal boundary, and that the survey should be extended north to the Murray River as soon as possible.

Wade’s assistant, Edward White, was chosen for this job, and he assembled a party of five for the job in August of 1849. It is interesting that a problem defined as urgent in 1845 was still unresolved four years later. By now a further complication had arisen: arrangements were being made for the colony of Victoria to be split off from New South Wales, and it would be nice if the western boundary could be properly defined by the time this happened.

In 1849 the drought was worse than two years earlier. Within two weeks White’s men deserted him, but he pushed on over the sand ridges by himself with three horses, marking the 141° line of longitude, hoping to reach the Murray River before running out of water. I have crossed from Victoria to South Australia  at 34° 26′ 37″ latitude, 32 miles from the Murray, and probably about where his men deserted him. I was in a 4wd vehicle; there was a reasonable gravel road to the border fence on the South Australian side; and a decent track on the Victorian side (this was some years ago); but I could see what it had been like before the roads were made. It was still the same a few feet away. I have great respect for White, and men like him.

How do you survey a straight line by yourself? The usual methods require two people. Edward White could have done it in some way like this. When his last helper left, he would have had a line marked on the ground by a series of wooden pegs driven into the ground. He would normally set up his theodolite over the last peg, aim south along the line at the furthest peg he could identify through the instrument’s telescope, then reverse the telescope to point exactly north, and direct a helper to put a series of pegs in a line as far as he could see. When he had to do the job alone, he must have ridden ahead until he could only see two pegs (probably at the top of the last two sand ridges, which are about a quarter of a mile apart in this area), then set up his theodolite at this point, adjusting its location until it was exactly in line with the last two pegs. Most likely, hoe would have to cut down some mallee to get a clear sight both north and south from the top of the ridge. Finally, he would cut a peg from a mallee tree, and drive it into the ground exactly under the theodolite, perhaps making the point more precise by driving a nail into the top of the peg to mark the exact line. Then he would move on to the next sand ridge. Because all he had to do was to mark a straight line, measuring distance was unnecessary.

One by one his horses died. When the last one died he managed to bleed the animal and slake his thirst with a cup of its blood before staggering on to the north on foot. In Australia this is called doing a perisher. He had no real idea of how much further he had to go to reach the river, but he must have realized he was getting close.

White did not perish. He reached the bank of the river only a couple of miles further on. He drank his fill, rested, then walked back to the dead horse to retrieve his saddle and bridle. He managed to cross the river and made his way to Chowilla sheep station, where he borrowed a horse and rode back to Adelaide. Crossing the river would be no easy feat today:  it is at least 300 feet wide, and is deep at this point. But there is a lock at Murtho in South Australia to keep the water level up. In 1849 there were no locks, and there was a drought, so the river would have been much lower, possibly just a chain of waterholes.

It is hardly surprising that the surveyed line was in the wrong place. It turned out that the original starting point was nearly two miles too far west, and the end point on the Murray River was about 2.3 miles too far west. This was determined in 1868 by a joint South Australian/New South Wales survey on the Murray River. But by now Victoria was an independent colony (and had sold or leased about 50% of the strip of land between the two locations for the boundary). For the next four decades South Australia tried to recover these 500 square miles. The matter was not settled until 1914, when South Australia lost its appeal to the Privy Council in England.

Now, why did Apple get the location of Mildura wrong? I think it was probably because the whole of this area is part of the Rural City of Mildura, which is something like a county in the U.S.A.

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