380 Miscellanies. 



nine, narceine, meconic acid, brown acid, an acid fatty matter, resin, 

 caoutchouc, gum, bassorine, and ligneux.. The narceine is the only- 

 one entirely new. 



Agreeably to Pelletier, of the twelve substances of which opium is 

 composed, four are electro-positive, (that is act as bases,) morphine, 

 narcotine, meconine, and narceine ; four are electro-negative, (that 

 is act as acids,) meconic acid, brown acid, fatty acid, and resin ; and 

 four are chemically indifferent ; caoutchouc, gum, bassorine and lig- 

 neux. The active properties of opium appear to reside in the elec- 

 tro-positive substances. Experiment, however, has not yet confirmed 

 this fact, in relation to narceine.* — Rev. Encyc. Juillet, 1832. 



4. Meconine. — The chemical history of this substance was read 

 by M. CouERBE, the discoverer, to the French Academy, on the 

 20th of August, 1832. 



It was discovered in 1830, by M. Couerbe, and about the same 

 time perceived and imperfectly described by M. Duhlanc. The 

 process followed, and described in details, by the former, is, in sub- 

 stance, the following. An aqueous solution of opium is filtered, 

 evaporated, and precipitated by dilute ammonia — the mass formed 

 in the ammoniacal fluid after a repose of fifteen or twenty days, is dis- 

 solved in boiling alcohol, and crystallised — these crystals are purified 

 by solution in boiling water, and by animal charcoal — the crystals, 

 which are again formed", are treated with boiling ether, which dis- 

 solves only the meconine, which is allowed to crystallize. Meco- 

 nine is white, crystallizes in six sided prisms, two sides of which are 

 larger than the others, terminated by a dihedral summit — without 

 smell — its taste, at first insensible, afterwards becomes acrid — at 90° 

 cent, it liquefies — melts completely at 90.50°, and remains fluid at 

 75° — at 155° it vaporises, and may be distilled unchanged — in cool- 

 ing it becomes a white mass — soluble in 265f parts of cold water, 

 and in 18.55 parts of hot water — more soluble in alcohol and ether, 

 and crystallizes from all these solutions. Heated with water it opa- 

 lises, the crystals become deformed, rise to the surface in flocculi, 

 then assume an oily appearance, and at length disappear ; dissolved 

 in water, it is precipitated by sub-acetate, but not by neutral acetate 

 of lead J it dissolves in most of the alkalies from which it is precipi- 



W 



* A very favorable report on Pelletier's memoir on Opium, was made to the Acade- 

 my of sciences, by Chevreul and Gay Lussac- 



