Lead chamber for production of sulphuric acid also known as Oil of Vitriol or H2S04, 1866. It was one of the most important industrial chemicals. The vapor is seen passing under and over lead curtains. Sulphur is being burned in open hearth at O. B is boiler supplying chamber with steam. From Cyclopaedia of Useful Arts by Charles Tomlinson. (London, 1866). Engraving.