THE ACTION OF VENOMS UPON ARTERIAL PRESSURE. 95 



Experiment No. 25. 



Normal 



Normal 



Time: 



Pressure 



min. sec. 



m. m. 





148 



10 



146 



30 



136 



1 00 



140 



1 '30 



140 



3 30 



150 



6 30 



150 



10 30 



146 



14 30 



152 



16 30 



156 



it No. 26. 





Time: 



Pressure 



min. sec. 



m. m. 





134 



10 



136 



30 



126 



1 00 



118 



1 30 



118 



3 30 



132 



5 30 



136 



1 30 



136 



9 30 



136 



11 30 



136 



18 30 



188 



Experiment No. 27. 



Normal 



Time: 



Pressure 



min. sec. 



m. m. 





130 









10 





20 



130 



1 00 



118 



2 00 



118 



4 00 



115 



10 





15 





REMARKS. 



Injected intravenously 0.003 gram dried Cobra venom dis- 

 solved in 1 c. c. distilled water with a few crystals of sodic 

 chloride and filtered. 



Clot formed in canula. Animal killed. 



Injected intravenously 0.006 gram dried Cobra venom pre- 

 pared as in the foregoing experiment. 



Convulsive movements; asphyxia; respiration ceased in three 

 minutes. 



130 Injected intravenously 0.003 gram dried Cobra venom dis- 

 solved in 1 c. c. distilled water. 



Clot in canula. 

 Dead from asphyxia 



The Action of Pure Venoms on the Blood Pressure of Animals in 'which the 

 Cervical Spinal Cord had been Divided. — Upon section of the spinal cord in the 

 upper cervical region, by which the influence of the vaso-motor centres in the 

 medulla is practically destroyed, the primary fall of pressure from venom is gener- 

 ally very slight, and after this diminution there is a secondary rise which may go 

 above the normal. In one experiment with Crotalus adamanteus venom there 

 was a rise of pressure for a moment at the time of injection ; in one experiment 

 with Crotalus horridns, in which a somewhat larger dose was used than in the 

 others, there was a distinct rise of pressure a few seconds after injection, followed 

 by a fall ; and in the experiment with the Cobra the pressure never went below 



