The Tide Gauge House

 This small bluestone building was constructed in the late 1857 by convict labour from the old prison hulks, and originally stood at Point Gellibrand. It was built to house one of three tide gauges that arrived from England in 1855.

 The gauge operated through an opening in the wooden floor. Tides were measured from here and Williamstown became the origin of the Australian Height Datum. The tide gauge continued to operate in this location until 1943 when silting up of the site interfered with its operation. It remained on Breakwater Pier until 1955 when the filling in of the boat harbour required that it be moved to its present site in the Commonwealth Reserve.

It now stands near the anchor of the ‘Nelson’, one of the flagships of the old Victorian Colonial Navy.