According to Krünitz, ‘Spruce is a most exquisite wood, which is especially consumed for this purpose in China because of the beautiful blackness which it yields when it is burned. There are immense forests of this type of wood in China, especially in the district of the city of Hoei-tcheou [Huizhou?]’. As Krünitz describes it, the Chinese also had specially built ovens for the production of soot from resinous wood. In Krünitz, 1820, Oekonomisch-Technologische Encyklopädie, Vol. 128, p. 732.