MASCAGNINE. 339 Observations. It is an opinion entertained by many, that this salt is the same with the sal ammoniac of the ancients; but the accounts of Pliny, Dioscorides, Col umella, Synesius, Herodotus, Strabo, and Arrian, prove that they understood by sal ammoniac rock-salt; and even the ancient Arabian physicians Avicenna and Sera- pion, who flourished during the eleventh century, describe rock-salt under the name sal ammoniac. The first ac count we have of sal ammoniac is in a treatise of Gcher’s, the date of which is uncertain.—Vid. Beckman, Beitriige zur Geschichte der Erfindungen, b. v. s. 254*,—285. 2. Mascagnine *, or Sulphate of Ammonia. Mascagnin, Karstcn. Mascagnin, Rcuss, b. ii. 3. s. 45. Id. Karsten, Tabel s. 56 Animoniaque sulphatee, Hauy, Tabl. p. 21.—-Mascognin, Lcnz, b. ii. s. 985. External Characters. Its colours are yellowish-grey and lemon-yellow. It occurs in mealy crusts, or stalactitic. Internally it is dull or glistening. The fracture is uneven or earthy. It is semi-transparent or opaque. Its taste is sharp and bitter. Y 2 Chemical * It is r.uincd after the discoverer M. Mascagni.