MINERAL POISONS. 93 



operates in some degree on the heart also. Fur- 

 ther experiments confirmed this suspicion. In 

 some of them the pulse soon became so feeble, 

 that it could be scarcely felt ; and its intermis- 

 sions were more frequent ; but in all cases the 

 heart continued to act after respiration had 

 ceased ; and the cessation of the functions of the 

 brain was therefore always the immediate cause 

 of death. When I employed artificial respira- 

 tion, after death had apparently taken place, I 

 seldom was able to prolong the heart's action 

 beyond a few minutes. In one case only it was 

 maintained for three quarters of an hour. I 

 never by these means succeeded in restoring the 

 animal to life, although the experiments were 

 made with the greatest care and in a warm tem- 

 perature. In some instances, after the artificial 

 respiration had been kept up for some time, 

 there were signs of the functions of the brain 

 being in some degree restored ; but the pulse, not- 

 withstanding, continued to diminish in strength 

 and frequency, and ultimately ceased. I shall 

 detail one of these experiments, as it serves to 

 illustrate the double action of this poison on the 

 nervous and vascular systems. 



EXPERIMENT VII. 



Some muriate of barytes was applied to a 

 wound in the side of a rabbit. The usual symp- 

 toms took place, and at the end of an hour the 

 animal was apparently dead ; but the heart still 



