on ike Living Si^stem, 29 



CHAPTER I. 



The effect of different powers applied to the 

 Hearts of Animals ivhilst in the Thorax and 

 in a State of Action. 



EXPERIMENT l. 



The sternum of a full grown frog was raised 

 and the heart exposed ; 



Hours. Minutes 



1. 35. Ten drops of water containing a 



grain of opium in solution were 



poured upon the heart, beating 6 1 . 

 38. The action of the heart has greatly 



diminished ; contracting not more 



than 45 in a minute. 

 45. Contractions not more than 38. 

 50. Contractions 29 in a minute, and 



feeble. 

 — Ten drops more of the same solution 



(i. e. one grain) wxre poured 



upon the heart. 

 55. Heart contracts 28 in a minute. 



2. — Twenty-eight contractions in a mi- 



nute. 

 10. Not more than 20 contractions in a 

 minute : animal beginning to be 

 convulsed. 



