Meet the man who helped keep colonial Queensland on time... by watching the stars!

Clocks, Towers and Time Keeping, Published 1 September 2026, Updated 1 November 2026

Imagine living in Queensland before GPS, smartphones, radio time signals or even reliable weather forecasts. How did ships navigate safely? How did surveyors accurately map the colony? And how did railway stations all keep the same time?

One of the key figures behind it all was Captain Henry O'Reilly (1824–1877), an Irish-born civil engineer, surveyor and astronomer who established a permanent astronomical observatory in Brisbane in the 1860s.

Now, don't let the title fool you. O'Reilly wasn't simply gazing through a telescope admiring the night sky. His observations had a very practical purpose.

Using a transit telescope and precision clocks, he carefully recorded the exact moments that stars crossed the local meridian. By doing so, he could determine Brisbane's local time with remarkable accuracy.

The accurate time determined from these observations could then be distributed through the telegraph network, helping government offices, railway stations and businesses synchronise their clocks. Accurate time was also invaluable to navigators entering Moreton Bay, allowing them to check the accuracy of their marine chronometers - essential instruments for determining longitude at sea.

But O'Reilly's work wasn't only about timekeeping.

Long before satellites and GPS, astronomers and surveyors relied on the positions of the Sun and stars to determine latitude, longitude and direction. Astronomical observations like these helped surveyors map Queensland's expanding frontier, establish property boundaries and produce accurate maps of the young colony.

It's remarkable to think that, before electronic time signals, Queensland's official time depended on careful astronomical observations made under the night sky. In the nineteenth century, astronomy wasn't just about exploring the universe - it was an essential tool that supported navigation, surveying, communication and the daily operation of a growing colony.

Today, Captain Henry O'Reilly is little remembered, yet he played a key role in establishing accurate timekeeping for colonial Queensland and demonstrated how astronomy could solve practical everyday problems.

So next time you look up at the stars, remember... those same stars once helped keep Queensland running on time.

Had you ever heard of Captain Henry O'Reilly? We'd love to hear your thoughts in the comments!

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Meet the man who helped keep colonial Queensland on time... by watching the stars!

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