in 1828. This process burned waste furnace gases in regenerative stoves, to heat up a lattice of fire bricks inside them. Once the bricks were sufficiently heated, the waste furnace gases were purged and replaced by fresh air intended to fire the furnaces. The fire bricks transferred their heat to this air, turning it into the 'hot blast' pumped into the furnaces.

No traces of the original small rectangular stoves remain, but foundations of the round Cowper Stoves,