POISON OF SOME INDIAN VENOMOUS SNAKES. 95 



5.25. Eeflex movement of leg much fainter when the ear is 

 irritated. 



5.31. Tries to get up voluntarily. Got up, staggered some 

 steps. Convulsive movements. Death. Immediately a cannula 

 was placed in the trachea and artificial respiration begun. 

 Sciatic nerve isolated. Irritated by induced current. Foot 

 twitched when secondary coil was at 57 cm. 



About 6.30. Electrodes screwed into cord about 2nd and 5th 

 dorsal vertebr£e. 



The strongest current of the coil produced contraction of the 

 muscles of the back, but no contraction of the limbs. The 

 sciatic nerve, when irritated directly, caused contraction of 

 foot with the coil at 23. 



6.50. Tlie pVirenic nerve irritated ; no contraction of 

 diaphragm ; vagus irritated ; heart stopped. 



In this experiment the continuance of reflex action on 

 irritation of the ear, and of voluntary movements, after reflex 

 action on irritation of the eye had disappeared, and almost up 

 to the time of death, are remarkable ; as is also the paralysis of 

 the phrenic before the sciatic and vagus nerves. 



Action of Cohra-poiso7i on the Circulation. 



In most cases of death from cobra-poison, the fatal issue is 

 not to be attributed to any failure of the circulatory apparatus ; 

 for the heart continues to pulsate vigorously, long after all 

 motions have ceased in the voluntary muscles and the strongest 

 irritation applied to the spinal cord and motor nerves fails to 

 produce the slightest effect. But this only occurs when the 

 dose of poison is not excessive ; and when a large quantity of 

 it is introduced at once into the circulation, the heart is not 

 exempted from its action, but is, on the contrary, most 

 seriously affected. This is seen in Experiments LXVIII and 

 XXVIII, where the poison having been either injected into the 

 circulation, or absorbed with extreme rapidity, the action of 

 the heart was at once arrested. But it is to be noted that it is 

 not paralysis, but tetanic contraction of the heart which is 

 produced, the poison, in fact, seeming to act as an excessive 

 stimulus; and this being the case, we feel less surprise on 



