Raw wool comes off a sheep's back heavy with grease, dirt, and lanolin, and before it could be sold at its best it had to be scoured - washed clean. That took enormous quantities of soft, warm water, which is exactly what central-west Queensland could not spare from the sky but could summon from below. The Great Artesian Basin, that vast reservoir trapped deep in the rock, rose here naturally warm and soft, ideal for the work. Before the scour could open, its founders sank a bore. The very first task, advertised in 1905, was to drill for water 'not more than three miles from the township of Blackall.' Everything else - the sheds, the engine, the bales - depended on that hot water coming up out of the ground.

The Blackall Proprietary Woolscouring Company was the work of five local grazing and business men, with John Henry Hart as chairman. In September 1906 they contracted Rockhampton builders Renshaw and Ricketts to throw up the shearing and scouring sheds in just four months, framing them in hoop pine carted from Maryborough on the far side of the colony. The plant opened in 1908 beside the newly laid branch railway, perfectly placed to receive fleece and dispatch clean, baled wool to the coast. In 1913 it changed hands, bought by the Melbourne-based Western Queensland Meat Export Company, which already ran a scour at nearby Barcaldine and set about wringing more output from the machinery.

Under its new owners the scour boomed. The company tinkered and upgraded relentlessly, and by 1918 it had more than doubled its 1913 output to 7,640 bales - the largest in the works' history. The peak years, 1916 to 1920, coincided with wool's importance to a world at war and just emerging from it. Allan Martin Ferguson managed the complex from 1913 until his death in 1933, after which his family carried on running it until 1957. Then the long decline set in. Other scours across the region had already begun shutting their doors, and one by one the great washing sheds of western Queensland fell silent. Blackall held on longer than the rest.

The Blackall Woolscour finally closed in 1978, the last of its kind in western Queensland to stop work - and, as it turned out, the last steam-driven scour anywhere in the country. What saved it was simple neglect of the right sort: nobody stripped it for parts. The engine, the boiler, the scouring train, and much of the ancillary gear all survived intact, sitting in their sheds beside the settling ponds and sheepyards exactly as the last shift had left them. Added to the Queensland Heritage Register in 1992 and marked by Engineers Australia for its engineering significance, the complex is now run for visitors. From around May to August each year, the 1908 engine is fired up again, and the sheds fill with the smell of hot oil and the rhythm of belts - a working memory of the industry that built the outback.