ELEMENTARY EXPERIMENTAL PHYSIOLOGY 



179 



or distress is caused by any resistance, and for this reason it is 

 impossible to determine the true volume unless the resistance of the 

 recording apparatus is low. Connect up two gas meters with a T-piece 



Fio. 177. A stetbograph employed to record the respiration and cardiac impulse 

 of the rabbit or cat. The tambours press on either side of the thorax. 1 he T tube 

 leads to a recording tambour. 



FIG. 178. Stethograph. A, Metal drum ; B, hooks for tapes which pass round 

 neck ; C, rubber discs ; D, hooks for attaching tapes which are tied round thorax ; 

 E, tube leading to the recording tambour. 



and determine the volume and rate of respiration before and after 

 running down and up a flight of stairs. 



