Tank Furnaces

The composition was melted in a large vat made of heat-resistant blocks heated laterally by burners.

The smallest ones had a capacity of just 6 tons while the biggest ones, enormous tanks almost 50 metres long by 10 metres wide and 1.5 meters deep, could hold 2,500 tons of glass.

As of the first quarter of the 19th century, production requiring large volumes of glass (for bottles, then plate glass) started using this method which was much more economical and, contrary to pot furnaces, allowed the use of a flux in continuous fusion.