Swan Street Richmond, looking east between 1874 and 1884. The tracks curving away to the left are towards East Richmond, the tracks curving to the right are to South Yarra. This was the first interlocked location in Victoria, (installed 1874) possibly Australia. Containing a 16 lever Saxby & Farmer frame and gatewheel, this frame was relocated to St Kilda in 1884. This crossing was abolished due to a grade separation project and new enlarged station in 1885. This photo was very likely taken before the Victorian Railways took over the Melbourne & Hobsons Bay United Railway Company.
If anyone knows of an earlier interlocking in Australia feel free to email me.