Beech Wood Distilled in an Iron Retort: Tar, Wood Vinegar and Charcoal

Heating hard wood in a closed iron vessel drives off a sour brown liquid, pyroligneous acid or wood vinegar, loaded with tar, and leaves charcoal behind. Andrew Ure (1839) describes the British works: iron cylinders set in brickwork, oak, ash, birch or beech only, and the crude liquor distilled again to leave the tar in the still. Beech tar is the starting point for Reichenbach's paraffin. The picture: a later, far larger plant: the vertical retort and wood conveyor of the Cliffs Dow wood distillation works in Marquette, Michigan.