488 DR T. R. FRASER ON SOME UNDESCRIBED TETANIC SYMPTOMS 



Brown and myself, that four-fifths of a grain of sulphate of methyl-strychnium 

 is about the minimum fatal dose for a full-grown rabbit* The amount of 

 strychnia that should be combined with this dose, in conformity with the ratio 

 of the last experiment, is about two-hundredths of a grain (or 2-66 minims of 

 liquor strychnia). 



Experiment LXIL — 2-66 minims of liquor strychnia? (containing 0*02 grain of 

 strychnia) was mixed with a solution of four-fifths of a grain of sulphate of methyl- 

 strychnia, in twenty-five minims of distilled water, and this solution was injected 

 under the skin at the right flank of a rabbit, weighing three pounds and four 

 ounces. The first symptoms occurred in seven minutes, and consisted of a slight 

 degree of exaggeration in the starts that were caused by irritating the nostrils of 

 the animal. In nine minutes, a series of spontaneous spasms occurred in the ante- 

 rior extremities ; and it was now obvious that the motor power of the posterior 

 extremities was slightly diminished. In nine minutes and thirty seconds, a 

 further series of spontaneous spasms occurred, but the spasms now involved the 

 whole body. In ten minutes, the rabbit lay down on the abdomen and chest ; 

 and after remaining quietly in this position for a minute, it was again affected 

 with spasms, during which it fell over on the side. In twelve minutes and ten 

 seconds, there was an attack of opisthotonic tetanus, which lasted for only ten 

 seconds, and was immediately succeeded by a second attack, and, on its termina- 

 tion, by a third, both also of short continuance. The rabbit was still lying on 

 the side, and appeared unable to change its position. At frequent intervals, a 

 series of feeble spasms now succeeded each other ; and at the termination of one 

 of these death occurred, fourteen minutes after the administration. 



The symptoms of paralysis and of spinal-stimulation observed in this experi- 

 ment do not, in their relation to each other, exactly resemble those of atropia. 

 Indeed, it was not anticipated that they would do so ; but it was anticipated 

 rather that the paralytic phenomena would be less marked, and that the spinal- 

 stimulant would, consequently, acquire a greater prominence than with atropia. 

 In the mixture of strychnia and sulphate of methyl-strychnium, the paralysis is 

 produced by an action on the motor nerves alone, which action affects frogs 

 much more rapidly and powerfully than mammals; whereas in atropia, it is 

 produced not only by an action on the motor nerves, but also by actions on the 

 sensory nerves, and, probably, on a portion of the spinal cord, and the additional 

 actions seem to affect frogs and mammals nearly equally. Therefore, while 

 frogs are more readily and completely paralysed than mammals by both atropia 

 and sulphate of methyl-strychnium, mammals are less readily paralysed by the 

 latter than by the former substance. Accordingly, the effects of the combination 

 of sulphate of methyl-strychnium and of strychnia more closely resemble those 

 of atropia in frogs than in mammals. 



* Loc. cit. pp. 160 and 196. 



