694 DRS CRUM BROWN AND FRASER ON THE CONNECTION BETWEEN 



methyl-atropium remains as a white mass. From this, the excess of iodide of 

 methyl is removed by a current of air, and the dry salt dissolved in water, 

 filtered, and evaporated at a temperature not exceeding 40° C. The concentrated 

 solution thus obtained, on cooling deposits the salt in prismatic crystals, appa- 

 rently belonging to the monoclinic system ; sometimes, part of the salt separates 

 as a heavy oil, which soon crystallises. These crystals have the composition 

 C 17 H 23 N0 3 CH 3 I. They are tolerably stable, bearing a temperature of 100° C. 

 without much alteration. When they are powdered, or when their solution is 

 warmed, a pleasant fruity smell is observed.* 



Pursuing the plan adopted in our former communication, we shall, in the 

 first place, describe the effects of this substance when it is exhibited by subcu- 

 taneous injection. As it is tolerably soluble in warm water, we were enabled to 

 administer sufficiently large doses in the form of solution. In the previous part 

 of this research, we found that the chemical addition of iodide, or sulphate of 

 methyl, or of ethyl, greatly diminishes the lethal f activity of strychnia, brucia, 

 thebaia, codeia, morphia, and nicotia. We have now to announce that a 

 similar operation performed on atropia, in place of diminishing, considerably 

 increases the lethal activity of this alkaloid. In our experiments with iodide of 

 methyl-atropium, we were somewhat surprised to find that a dog was rapidly 

 killed by the subcutaneous injection of ten grains, and that a rabbit survived for 

 but a short period after the administration of three. We shall first describe the 

 experiment referred to on a dog, as it illustrates not only the difference between 

 the lethal activity of iodide of methyl-atropium and that of atropia, but also 

 some of the more prominent differences between the symptoms produced by these 

 two substances. 



Experiment I. — A solution of ten grains of iodide of methyl-atropium, in 

 about one hundred minims of warm distilled water, was injected under the skin 

 of a healthy English terrier, weighing eight pounds and six ounces. In a few 

 minutes, there was some difficulty in performing voluntary movements, and in 

 ten minutes this was more marked. Soon after, the anterior extremities became 

 gradually more and more weak, until they could no longer support the body, 

 and the dog subsided on the chest, with the muzzle resting on the floor. In 

 thirteen minutes, it fell over on the side in a state of flaccid helplessness ; the 

 respirations became somewhat laboured and shallow, and their frequency dimin- 

 ished until, at twenty-three minutes, only an infrequent gasp occurred. There 

 were now some faint twitches in the panniculus carnosus muscle and in the 

 musles of the limbs ; and irritation of the skin still excited feeble reflex move- 



* We shall give details of the chemical relations of the methyl derivatives of atropia on some 

 other occasion. 



f We have employed the phrase " lethal activity" as a substitute for the French " 1'activite 

 toxique," or death-producing action. 



