It took place when one of the wooden vats of fermenting porter burst. Fermentation then takes place, usually in temperature controlled stainless steel vats. After pressing, the juice is put into fermentation vats. Dated to BC, the site contained a wine press, fermentation vats, jars, and cups. English cider contained a drier, higher-alcohol-content version, using open fermentation vats and bittersweet crab apples. Large vats of seawater were heated using coal; as the water evaporated the salt remained. Buffalo Cave near Jamestown was also a major mine with twelve leaching vats. The brewing industry gradually stopped using large wooden vats after the accident. They made the large wooden vats in which beer was brewed. The mix is then stirred in oak vats until blended. Another hazard was the nitrogen dioxide fumes coming off the nitric acid vats. Bulk materials are added via automatic measuring devices into stainless steel cooking vats. The algae were grown in vats underneath artificial light. Clones grown in vats are revealed to be the predominant source of cheap labor. Mavrodaphni is initially vinified in large vats exposed to the sun.