The Survey Marker hidden in Samuel Calvert's view of Mount Alexander, 1862

 

In a previous article I discussed what I thought was the most likely place the artist stood to sketch what eventually became Samuel Calvert's etching 'Mount Alexander, From near the Railway'. I concluded that it must have been somewhere on, or near, Post Office Hill Chewton. Despite being confident the view from the hill in 1862 would have been somewhat similar to that depicted in the etching, there are some major discrepancies. These include the incorrect scale of the mountain itself (its profile is too narrow), the fanciful foreground which pictures Forest Creek as some idyllic picnicking spot, and the failure to accurately show Forest Creek winding between the two hills that frame Mt Alexander.

    Nevertheless there is one intriguing feature in the etching of Mount Alexander which appears to have been deliberately placed. The artist and Samuel Calvert have made sure to include what appears to be an early survey marker. Here is a closeup of the etching which more clearly shows the structure marked at the top of the mountain in the etching.

  

   As soon as Europeans arrived in Australia in the 18th century they had begun to map the land. To do this they needed to use surveying equipment to work out, as accurately as they could, the spatial relationships between features on the ground. Thomas (Major) Mitchell's exploration of this region in 1836 was such an example. Mitchell made it a priority to scale the most notable of the mountains that bordered his expedition's path so he could triangulate his exact position. When Mitchell made it to the top of Mount Alexander (which he named Mount Byng) he "found it but thinly wooded so that I could take my angles around the horizon without difficulty". Later, of Mount Macedon, he writes: "I had two important objects in view in ascending this hill; one being to determine its position trigonometrically as a point likely to be seen from the country to which I was going, where it might be useful to me in fixing other points; the other being to obtain a view of Port Phillip, and thus to connect my survey with that harbour". (Both quotations from 'Three Expeditions Into the Interior of Eastern Australia, Vol 2').

    Quite obviously, the earliest map makers and surveyors had to rely on locating a distinctive tree or rock formation at or near the summit to take their bearings from. But as soon as possible some more distinctive and more highly visible structure was erected. 

    We know that by the 1870's stone cairns built around tall flagstaffs or flagpoles were being erected on the tops of  mountains in Central Victoria. The stone survey cairn on the summit of Mount Alexander was built in 1876 (photo below). It's one of only three formally constructed stone survey cairns still surviving today. The other two are on Mount Macedon and in the Warby-Ovens National Park.

    But what was being used on Mount Alexander before this time? Intriguingly Calvert's etching gives us a clue. Not only does it appear to show a flagstaff placed on a tall rock or perhaps in a cairn of rocks, it shows that it might not have been on the summit, the eventual location of the above survey cairn. It appears to have been erected some distance south of the summit on a secondary peak or hill.

    Here is an excerpt from a map of Mount Alexander (courtesy of Cartography Community Mapping).

    Marked on the map is Trig Point 1862? which to me is the likely location of the survey marker shown in the etching. Here is a marked version of the original etching.

        Compare it to a photo of how the mountain looks today with the same features marked.

    Here's a Google Earth view which shows how I reached the conclusion that from Post Office Hill the summit of Mount Alexander is far to the left and the secondary peak to the right in the photo above. We know that the 1876 summit survey cairn is very close to a transmission tower- the small one to the left of two extremely tall TV masts. Even though the latter two masts are north of the summit cairn they appear to be to the right because of the angle of observation.

    So the question might be asked, why was the first survey marker placed below the summit? The answer lies in the fact that from the top of the distinctive granite hill of the secondary peak (now much undermined by past quarrying) there are extensive views to the east, west and south. The actual summit is rather nondescript, and it's by no means easy to tell if one is actually at the highest point there. Quite possibly the slightly lower peak was chosen because it was much more visible. And perhaps it had a feature which was used by surveyors before the early survey marker was constructed. Just below the granite hill there's a distinctive rock which would have been visible for some distance to the west and south . Quite possibly the rock below was the first feature that map makers worked from. We're hardly likely to ever know but it's interesting to speculate on the choices the early surveyors had to make in the course of mapping the country.

    Since writing this I've discovered an early topographical survey map from 1857 which appears to confirm my hypothesis. I've overlaid an excerpt from this map over the above map of Mt Alexander accessed at  Cartography Community Mapping. Even though the overlap isn't exact it seems to indicate that the summit was considered to be, at that time, the secondary peak described above.