ANTISEPTIC ACTION OF ALCOHOL 



157 



very perceptible latent period, cause a change in the heart 

 beat either producing an acceleration of the rate or in- 

 creasing the strength of the beat (augmentor effect). If 

 possible, secure tracings showing these effects on the heart. 

 How do these records compare with the action of adrena- 

 line on the heart? Do you know of any other drugs that 

 act on the heart similarly to adrenaline? Watch for these 

 later in your course. Kill the animal by asphyxia. 



EXPERIMENT XV. 

 Antiseptic Action of Alcohol. 



1. Obtain four fermentation tubes (Fig. 150). Place a 

 cake of yeast in two hundred cubic centimeters of water, 



Fig. 150. Fermentation tube. 



add some glucose and shake up the mixture thoroughly. 

 Pour out enough of the mixture to fill one fermentation 

 tube, add sufficient absolute alcohol to the mixture to make 



