One of the requirements for smelting – a process of extracting a metal from an ore – is a flow of oxygen. Today, blast furnaces blow oxygen into the furnace to achieve this goal. Ancient furnaces however had to rely on human power to pump the bellows, or did they?
What if the wind blew in such a predictable way that it could be used to fan the fires of your smelting furnaces?
This is exactly what happened in Sri Lanka as early as the 7th century AD, resulting in the production of high carbon steel. The story of this discovery and its significance is well worth reading.
The best part however, is that this long lost process has been recreated at the Martin Wickramasinghe museum in Koggala.