56 



Observations on Ojnum and its Tests. By Andrew Ure, 

 M.D.,F.R.S., &c. 



Few subjects of chemical research are more interesting to 

 medical science than the constitution of opium. The poppy, 

 like every other vegetable, must vary in the quality of its se- 

 creted juices, with soil, climate, and season; whence corre- 

 sponding changes will ensue in the nature of the inspissated 

 product. Did the anodyne and soporific virtue of this medi- 

 cine reside in one definite principle, chemical analysis might 

 furnish a certain criterion of its powers. It has been pretty 

 generally supposed that this desideratum is supplied by Ser- 

 tiirner's discovery of morphia. Of this narcotic alkali not 

 more than seven parts can be extracted by the most rigid 

 analysis from one hundred of the best Turkey opium ; a quan- 

 tity, indeed, somewhat above the average result of many skilful 

 chemists. Were morphia the real medicinal essence of the 

 poppy, it should display, when administered in its active saline 

 state of acetate, an operation on the living system commen- 

 surate in energy with the fourteen-fold concentration which 

 the opium has undergone. But so far as may be judged from 

 the most authentic recent trials, morphia in the acetate seems 

 to be little, if any, stronger as a narcotic than the hetero- 

 geneous drug from which it has been eliminated. Mr. John 

 Murray's experiments* would, in fact, prove it to be greatly 

 weaker ; for he gave two drams of superacetate of morphia to 

 a cat, without causing any poisonous disorder. This is per- 

 haps an extreme case, and may seem to indicate either some 

 defect in the preparation, or an uncommon tenacity of life iq 

 the animal. To the same effect Lassaigne found that a dog 

 lived twelve hours after thirty-six grains of acetate of morphia 

 in watery solution had been injected into its jugular vein. The 

 morphia meanwhile was entirely decomposed by the vital forces, 

 for none of it could be detected in the blood drawn from the 

 animal at the end of that period f . Now, from the effects pro- 

 duced by five grains of watery extract of opium^ injected by 

 Orfila into the veins of a dog, we may conclude that a quantity 



* Ediii. Phil. Jonrn. vii. 388. 

 f Annales de China, et Phys. xxv. 102. 



