Dr. Ure on Opium and its Tests, 57 



of it, equivalent to the above dose of the acetate of morphia, 

 would have proved speedily fatal. 



Neither can we ascribe the energy of opium to the white 

 crystalline substance called narcotine^ extracted from it by the 

 solvent agency of sulphuric ether ; for Orfila assures us that 

 these crystals may be swallowed in various forms by man, even 

 to the amount of two drams in the course of twelve hours, with 

 impunity ; and that a dram of it dissolved in muriatic or nitric 

 acid may be administered in the food of a dog without pro- 

 ducing any inconvenience to the animal. It appears, however, 

 on the same authority, that thirty grains of it dissolved in acetic 

 or sulphuric acid caused dogs that had swallowed the dose to 

 die under convulsions in the space of twenty-four hours, while 

 the head was thrown backwards on the spine. Oil seems to be 

 the most potent menstruum of narcotine ; for three grains dis- 

 solved in oil readily kill a dog, whether the dose be introduced 

 into the stomach or into the jugular vein. 



Since a bland oil thus seems to develop the peculiar force 

 of narcotine, and since opium affords to ether, and also to am- 

 monia, an unctuous or fatty matter, and a resin (the caout- 

 chouc of Bucholz) to absolute alcohol, we are entitled to infer 

 that the activity of opium is due to its state of composition, to 

 the union of an oleate or margarate of narcotine with morphia. 

 The meconic acid associated with this salifiable base has no 

 narcotic power by itself, but may probably promote the activity 

 of the morphia. 



Hence, though the weight of morphia obtainable from a given 

 variety of opium may by no means represent the total essence 

 of the drug, yet its quantity is most probably proportional to 

 the powers of the opium. But morphia exists in the state of 

 a meconate, and its quantity must be in equivalent ratio to 

 that of the meconic acid. On this principle, a ready mode 

 seems to offer of trying the comparative narcotic powers of 

 different opiums. Let a grain or two of each be dissolved in 

 a little dilute alcohol, and then diffused through such a body 

 of water as will make the liquid nearly colourless. Pour each 

 liquid into a graduated glass cylinder, and add to it a few drops 

 of red muriate (or tincture of muriate) of iron. The character- 

 istic brown-red tint will immediately appear, of a depth pro- 

 portional to the meconic acid, and equivalent to the morphia 



