While the production of wheat was restricted by climate, soil fertility and plant diseases, the conversion of grain to flour was largely influenced by issues of technology transfer.

The first grain was ground with forty iron hand mills which quickly wore and had an output as little as one bushel per twenty four hours.

[4] As early as 1791 Governor Phillip noted that a windmill was urgently needed, although Lieutenant-Governor Philip Gidley King argued that the building of a mill would be too labour-intensive and expensive and stone querns presented a more practical option.

Various other problems including storms, theft, inexperienced operators and an economy drive by the British government further slowed the development of milling.

King was advantaged by the availability of more suitable timber and the use of Nathaniel Lucas, a convict who was an experienced carpenter with knowledge of millwrighting.

[1] The development of water mills, specifically, was hampered by the Australian climate, characterised by variable rainfall and consequent variation in river flow.

Early attempts at Parramatta in 1779 and 1803 failed due to intermittent water flows and dam collapse, poor sighting, bad construction and a continuing lack of skilled labour.

[1] Over time, the matriarch and a number of the Lucas children made either temporary or permanent moves to the Launceston area in Van Diemens Land.

The family established a number of inter-related businesses, culminating in a regular trade between Van Diemens Land and Sydney Cove.

[1] On 5 May 1818 Nathaniel Lucas' body was found in the Georges River at Liverpool, his death having "proceeded from his own act, owing to mental derangement".

He moved to Sydney with his family at the age of 9 and eventually followed in the footsteps of his father, apprenticing in carpentry and milling and pursuing various entrepreneurial ventures.

His substantial investment in his 1822 watermill on Harris Creek, known as the Brisbane Mill, in modern-day Voyager Point was hampered by a series of drought and flood.

In the meantime Mr. Lucas will receive good Wheat free from smut at the Liverpool Warehouse, and pay for the same as fair as the Settler can sell in Sydney.

The following Goods he offers for Sale :- Hyson and Hyson skin teas, sugar, soap, calico, prints, checks, cloth and handkerchiefs, of colours; crockery ware of sorts; hand, pit and cross-cut saws; files and nails, of sizes; rum, gin, wine and porter, in quantities not less than five gallons; with every other Sort of Good that is for Sale in Sydney.

With his partner Daniel Cooper he owned the Waterloo Warehouse, a very large 5 storey building located at 72 George Street Sydney.

[29] Getting these large items and the mill stones weighing approximately a ton each from boats to the site would have required a substantial labour force.

Some clearing of the woodland was undertaken on the southern riverbank to allow for modest accommodation to be constructed and perhaps also limited livestock and cultivation of crops.

On Wednesday 17 September 1828 John Lucas was declared bankrupt in The Sydney Gazette and New South Wales Advertiser with trustees appointed to deal with his estate.

[1] On Monday 5 November 1832 the Sydney Morning Herald, documented the transfer of both of John Lucas' mills and associated land to Solomon Levey.

On Monday 2 December 1839 The Sydney Monitor and Commercial Advertiser declared the sale of flour, bran and pollard at Coopers Brisbane Mill in any quantity.

On 18 May 1843 Major Sir Thomas Mitchell, then Surveyor General of New South Wales, wrote to the governor describing the "direct line of road to the Illawarra" that he had surveyed and was being built.

[1] The Dharawal people are the traditional custodians of the land extending from Botany Bay to the Shoalhaven River and Nowra and inland to Camden.

Evidence of their tracks, camps and significant sites are scattered across the region, and continue to have meaning for the Dharawal people today.

They were constructed with convict labour and, together, show Lucas' attempts to continuously adapt his milling strategy in the face of environmental challenges.

The adaptation of technology across the two sites, and Lucas' ultimate failure to make this milling venture economically viable demonstrates the difficulty of food production, in particular the conversion of grain to flour in the new colony.

The story of Lucas' watermills is also of state significance for its ability to communicate the entrepreneurial aspirations of 1820s New South Wales colonials.

[1] The Lucas Watermills Archaeological Sites were listed on the New South Wales State Heritage Register on 30 August 2017 having satisfied the following criteria.

[1] The place is important in demonstrating aesthetic characteristics and/or a high degree of creative or technical achievement in New South Wales.

Remnants of other water driven flour mills exist elsewhere in the state, however these are some of the earliest and are the only substantial remains in the Sydney metropolitan area, having been relatively undisturbed.

Lucas' sites and their evolution provide good representative examples of early milling infrastructure in NSW which required much experimentation to meet local environmental and logistical constraints and were largely ultimately unsuccessful.