RESPIRATION 



107 



For the following experiments the slowest rate of drum is to be 

 used, and the subject must not be allowed to see the tracing which is 

 being taken. 



Record of respiratory movements. Apply a stethograph (Marey's 

 or Sanderson's) (Fig. 81) to the chest, and register the movements of 

 respiration by means of a recording tambour. 



775 



FIG. 82. Spirometer arranged to register, upon a slowly revolving drum, the 

 amount of air respired. gp. t Body of spirometer ; cy, measuring cylinder 

 with scale and writer attached ; v, v', water valves ; ra, mouthpiece. 



Remove the lever of the recording tambour from contact with the 

 drum. Cause the subject to take a number of deep respirations at a 

 rapid rate. Then let him cease these voluntary efforts ; take a record 

 of the ordinary breathing which succeeds them. There will probably 

 be a pause (apncea), followed by respirations which are at first shallow 

 but gradually become of the ordinary character. 



