Comp. Opium contains a peculiar acid, the Meconic (3 HO, C14HO11+6HO); four alkaloids, viz., Morphia (C34 H 19 NO6), Codeia (C3sH2INO6+ 2HO), Papaverina (C40 H21 NO8), and Thebaia, or Para-morphia (C38H21NO6); and several neutral crystallizable bodies, viz., Narcotine (C48H25NO14), Narceia (C46 H29 NO18), Meconine, or Opianyl (C 20 H 10 O 8), and Opianine and Porphyroxine, principles whose composition is at present not understood. It also contains several Resins, gummy, fatty, and extractive matters, caoutchouc, a trace of Volatile Oil, and inorganic salts, Of these principles Morphia and Codeia are narcotic and sedative. Narcotine is tonic and anti-periodic. The action of the other principles is unknown. Dr. Garrod states that the resinous matter possesses considerable power. In one case in which it was administered in rather large doses, giddiness and great contraction of the pupils ensued.