176 DRS CRUM BROWN AND FRASER ON THE CONNECTION BETWEEN 



We obtained the same results on repeating these experiments with half-grain 

 doses of iodide of methyl-thebaium. 



These experiments demonstrate clearly that the methyl derivatives of thebaia 

 produce their principal physiological effects by impairing and destroying the 

 function of the peripheral termination of the motor nerves— an action that is very 

 different from that of thebaia itself. They also differ from thebaia in being con- 

 siderably less potent as poisons. Several of these characters are summarised in 

 the appended table. 



No. of 

 Experiment. 



Substance 

 employed. 



Animal and its 

 weight. 



Method of 

 exhibition. 



Dose. 



Effect. 



LXIL 



Iodide of methyl- 

 thebaiurn. 



Rabbit,21bs.l2oz. 



Subcutaneously. 



8 grs. (contain- 

 ing 5'5 grs. of 

 thebaia). 



Paralysis in 45 minutes, 

 continuing for about 30 

 minutes, and followed by 

 recovery. 



LXVI. 



Thebaia. 



Do. (same rabbit 

 as in Experiment 

 LXIL) 



Subcutaneously, 



02 gr. 



Tetanus in 52 minutes, 

 and death in 54 minutes. 



LXXI. 



Iodide of methyl- 

 thebaium. 



Do., 4 lbs. 6 oz. 



By stomach. 



30 grs. (contain- 

 ing 20"6 grs. 

 of thebaia). 



No effect. 



LXXIV. 



Thebaia. 



Do. (same rabbit 

 as in Exp. LXXI.) 



By stomach. 



4 grs. 



Tetanus in 6 minutes, and 

 death in 19 minutes. 



LXXVII. 



Sulphate of me- 

 thyl-thebaium. 



Do., 3 lbs. lHoz. 



Subcutaneously. 



4 - 5grs. (contain- 

 ing 3*7 grs. of 

 thebaia). 



Paralysis in 21 minutes, 

 continuing for 2 hours 

 and 9 minutes, and fol- 

 lowed by recovery. 



LXXXI. 



Sulphate of me- 

 thyl-thebaium. 



Do., 4 lbs. 4 oz. 



By stomach. 



20 grs. (contain- 

 ing 16G grs. 

 of thebaia). 



Xo effect. 



CODEIA (C 18 H 21 N0 8 + H 2 0). 



We have examined the effect of the addition of iodide and sulphate of 

 methyl to codeia— an opium alkaloid, which, according to Claude Bernard, is 

 the second in toxic activity, and possesses distinct convulsant but feeble soporific 

 properties.* 



Iodide of methyl- codeium. — Howf obtained by the action of iodide of ethyl on 

 codeia, iodide of ethyl-codeium, and from it a number of ethyl-codeium com- 

 pounds, and proved that codeia is a nitrile base. As was to be expected, iodide 

 of methyl acts even more readily on codeia.^ It is only necessary to heat codeia 

 with a little alcohol and an excess of iodide of methyl to 100° C. for an hour, in 

 a sealed tube, to complete the reaction. The excess of iodide of methyl is distilled 

 off, the alcohol evaporated, and the product crystallised from hot water. It 



* Comptes Rendus, vol. lix. (1864) p. 413. 

 f Chemical Society's Quarterly Journal, vol. vi. (1853) p. 134. 



X We shall give details of the chemical relations of the methyl derivatives of codeia on some 

 other occasion. 



