The “Williamstown Observatory was established in July 1853″ [1]. ” The work of the Williamstown Observatory was wound down in mid 1863, as instruments were progressively moved to the new Melbourne Observatory, which formally commenced operation on 9 June 1863.” [ibid]. The Williamstown one is long gone, but the Melbourne one is still proudly standing.
In researching the exact location of the Williamstown Observatory (see this fascinating discussion), I’ve just spotted an interesting – and possibly related – situation with the location of the Melbourne Observatory.
Using the excellent Trove website, it was fairly easy to find historical values for the position of the Melbourne one. For example, The Argus newspaper, Monday 28 Aug 1871 on Page 4 has an article headed MELBOURNE OBSERVATORY [2].
It gives the 1871 values as:
Lat. 37deg. 49min. 53sec. S. ; long. 9h. 39min. 54.8sec.
Directly converting these to decimal values gives:
-37.89805556, 144.9783333 E (- means South)
The above is a simple conversion, not a transformation (viz not taking into account differing projections, datums etc). Google Earth says the ‘modern’ values of the actual Observatory’s location are:
-37.829660° 144.975582° E
Putting both historical and modern values into Google Earth shows:
As the drawn line shows the Longitude is quite close (the ‘sea/historical’ one being almost directly south of the ‘land/modern’ one) but the Latitude is out by 7.6 km.
So the next mission to try and work out what’s going on. My first suggestion would be I’d need to apply a transformation of some sort, to take into account the different datums, projections etc.
It follows that I’ve looped back to the same mission as what started all of this – doing the transform for the Williamstown Observatory. I’m not at all unhappy with that. I’d assume it’s the same piece of work for both. Plus Melbourne is back in Stage 3 COVID-19 lock-down, so I do have some time.
An 1872 letter on ‘The Longitude of Melbourne’
I also stumbled on a fascinating ‘defence’ of the accuracy of the 1870s longitude of the Melbourne Observatory. It took the form of a letter to the editor of The Age newspaper entitled “THE LONGITUDE OF MELB0URNE” on 29 August 1872 [3]. From the pen of the famous Robert Ellery, a key early player in both Observatories.
References
[1] Gillespie, R. (2008) Williamstown Observatory, 1853-1863 in Museums Victoria Collections https://collections.museumsvictoria.com.au/articles/1629
Accessed 12 July 2020
[2] MELBOURNE OBSERVATORY. (1871, August 28). The Argus (Melbourne, Vic. : 1848 – 1957), p. 4. Retrieved July 12, 2020, from http://nla.gov.au/nla.news-article5854093
[3] “THE LONGITUDE OF MELB0URNE.” The Age (Melbourne, Vic. : 1854 – 1954) 29 August 1872: 3. Web. 12 Jul 2020 <http://nla.gov.au/nla.news-article199373876>.