BOLOGNESE. See GRIMALDI.
BOLOGNIAN or BONONIAN STONE, a phosphoric substance first discovered near Bologna in Italy, whence it received its name. It has been supposed to contain some metallic matter, on account of its great specific gravity; but it is now found to be only a compound of ponderous earth and vitriolic acid. It differs, however, from the artificial barofelenite in the proportion of its ingredients, the latter containing 33 parts of vitriolic acid and 67 of earth; the former 84 of earth, 13 of the most concentrated vitriolic acid, and three of water. Mr Scheffer, in the Memoirs of the Academy at Stockholm, for the year 1753, has communicated some experiments on a stone of this kind from China, which prove, that it perfectly agrees with the descriptions given in several books of a stone called petunse by the Chinese, and which is said to be used in their porcelain manufactures.