28 Observations and Experiments on Opium. 



separated from this substance has very little odour and the 

 denarcotized extract and laudanum possess less, in fact so lit- 

 tle that they could hardly be detected as preparations of opi- 

 um by the odour ; the strong odour of the extract arises from 

 the oil of opium which it contains. The activity of Baume's 

 celebrated extract, is considered by Neuman to reside in the 

 oil and resin. The acid which exists in this compound has 

 not been sufficiently examined to enable us to say any thing 

 definite in relation to it. The characters of the caoutchouc 

 are very prominent. I have not tried the effects of this com- 

 bination upon animals, nor have I seen a description of it, 

 but judging merely from its sensible characters, it would ap- 

 pear more active than the narcotine. 



Morphia. 



This substance exists in opium in union with meconic 

 acid, its action on the human body is that of a sedative, and 

 it possesses all the advantages which we may expect to find 

 in opium, without any of its inconveniences. Different 

 modes of preparation have been described by Robiquet, De- 

 rosne, Choulant, Statuerner and others. Dr. Thomson gives 

 an easy method to obtain it in a state of purity. He employs 

 ammonia instead of magnesia, to decompose the natural 

 meconiate, &c. (see Annals of Philosophy for June, 1820.) 

 The sedative powers of morphia become more manifest, 

 when combined with an acid, particularly the acetic, which 

 arises from increasing its solubility. Morphia is very soluble 

 in olive oil, and according to the experiments of M. Majendie, 

 the compound acts with great intensity. I am indebted to 

 Dr. Coxe for the following interesting history of the crysta- 

 line forms of its saline compounds. 



The Carbonate crystalises in short prisms. 



The Acetate in soft silky prisms, and is very soluble and ex- 

 tremely active, more so than any other combination of mor- 

 phia. 



The Sulphate in arborescent crystals, next in solubility to 

 the acetate and rather less active. 



The Muriate in plumose crystals, much less soluble; when 

 evaporated, it concretes into a shining white plumose mass on 

 cooling. 



The Nitrate in prisms grouped together. 



The Meconite in oblique prisms sparingly soluble, 



The Tartrate in prisms. 



