Note 1053 — BOLOGNA STONE.
William Johnston translation
Marggrafs Chymische Schriften, ii. p. 119. This author says the cakes must be only as thick as the back of a knife; but that which I obtained in the year 1782 from Bologna, was an inch English measure in diameter, and two lines in thickness. It still weighs, after the brass box in which I long preserved it between cotton in a luminous state, has become black, and itself has lost its virtue, three drachms. In colour it has a perfect resemblance to the star which Marggraf prepared from German stones, and presented to Professor Hollman, and which is now in my possession. It is contained in a capsule of tin plate, over which a piece of glass is cemented.