178 On the different Modes in which Djsath 



ligature, and on the following day he had recovered the use 



of the limb. 



Exp. 29. T repeated the experiment a third time, draw- 

 ing the ligature very tight. At the end of forty-five minutes 

 the animal continued perfectly well, and the ligature was 

 removed. I watched him for three quarters of an hour af- 

 terwards, but there were no symptoms of his being affected 

 by the poison. On the following day the rabbit died ; but 

 this I attribute to the injury done to the limb and sciatic 

 nerve bv the ligature, as there was the appearance of in- 

 flammation in the parts in the neighbourhood of the liga- 

 ture. . 



These three experiments were made with the greatest 

 care. From the mode in which the poison was applied, 

 from the quantity employed, and from my prior experience, 

 I should liave entertained not the smallest doubt of the 

 poison taking effect in every instance in less than twenty 

 minutes, if no ligature had been applied. In two of the 

 three, the quantity of woorara was more than had been used 

 in any former experiments. 



I have not judged it necessary to make any more experi- 

 ments, with the ligature on the limb, because the numerous 

 experiments of the Abbe Fontana on the ticunas, coincide 

 in their results with those which have just been detailed, 

 and fully establish the efficacy of the ligature in preventing 

 the action of the poison. It is not to be wondered at, that 

 the ligature should sometimes fail in its effects, since these 

 must evidently depend on the degree in which the circula- 

 tion i« obstructed, and on the length of time during which 

 the obstruction is continued. 



There can be little doubt that the woorara affects the 

 brain, by passing into the circulation through the divided 

 vessels. It is probable that it does not produce its effects, 

 until it enters the substance of the brain, along with the 

 blood, in which it is dissolved ; nor will the experiments of 

 the Abbe Fontana, in which he found the ticunas produce 

 almost instant death when injected into the jugular vein of 

 a rabbit, be found to militate against this conclusion, when 

 we consider b.ow short is the distance which, in so small 

 an animal, the blood has to pass from the jugular vein to 

 the carotid artery, and the great rapidity of the circulation ; 

 since in a rabbit under the iuffuence of terror, during such 

 an experiment, the heart cannot be supposed lo act so sel- 

 dom as three times in a second. 



I have made no experiments to ascertain through what 



medium 



