Seirogan ingredient. That ingredient in the West may otherwise go by such names as "wood creosote", "beechwood creosote", or "liquid pitch oil", and should be distinguished from industrial "coal-tar creosote". To emphasize the distinction, wood creosote in Japan is sometimes called by such names as and minor variants thereof. The wood creosote is blended with two or more recognized in for their antiseptic and other effects, but the additional ingredients used are different among manufacturers (See under #Chemical composition for a sampling of formulas). Some quarters (perhaps kanpō medicine practitioners and others) insist however that "Seirogan is not strictly speaking kanpō
Tar wood causes tar and pitch to drip away from the wood and leave behind charcoal. Birch bark is used to make particularly fine tar, known as "Russian oil", suitable for leather protection. The by-products of wood tar are turpentine and charcoal. When deciduous tree woods are subjected to destructive distillation, the products are methanol (wood alcohol) and charcoal. Tar kilns (, , , ) are dry distillation ovens, historically used in Scandinavia for producing tar from wood. They were built close to the forest, from limestone or from more primitive holes in the ground. The bottom is sloped into an