Queensland State Archives posted a photo:
A silo is a structure for storing bulk materials. Silos are used in agriculture to store grain but are also used for bulk storage of coal, cement, carbon black, woodchips, food products and sawdust. Three types of silo are in widespread use today: tower silos, bunker silos, and bag silos.
Tower silos are cylindrical structures typically 3 to 27 m in diameter and 10 to 90 m in height. They can be made of many materials; wood staves, concrete staves, cast concrete, and steel panels have all been used, and have varying cost, durability, and airtightness tradeoffs. Silos storing grain, cement and woodchips are typically unloaded with air slides or augers.
In Canada, Australia and the United States, many country towns or the larger farmers in grain-growing areas have groups of wooden or concrete tower silos, known as grain elevators, to collect grain from the surrounding