PHYSIOLOGY OF RESPIRATION. 



LESSON LYI. 



MOVEMENTS OF THE CHEST WALL- 

 ELASTICITY OF LUNGS - 

 HYDROSTATIC TEST. 



1. Movements of the Chest Walls Stethograph. 



A. Rabbit. (a.) Arrange a drum and time-marker. Fix 

 a rabbit conveniently, and with tapes tie on its chest Marey's 

 double-tambour, connecting the latter with a recording 

 tambour adjusted to write on the drum. Introduce between 

 the receiving and recording tambour either the valve usually 

 supplied with Marey's apparatus, or a T-tube with a screw 

 clamp, whereby the pressure within the system of tubes can 

 be regulated. Take a tracing. If one of the receiving tam- 

 bours be placed over the cardiac impulse, the tracing will 

 show also the number of beats of the heart. 



B. Man Stethograph (Marey). (a.) Cause a person to 

 expose his chest. Raise the screw (<?) of the Stethograph, 

 and fix the plate (f) of the instrument on the chest, with 

 tapes attached to (c) and (d). Depress (g), connect the tube 

 (a) with a recording tambour, with the same precautions as 

 in 1, A, and take a tracing. Examine the tracing, noting 

 the relation between inspiration and expiration. 



2. Stethometer of Burdon-Sanderson. 



(a.) Prepare a drum and time-marker, as in the previous 

 experiments. Cause the person to expose his chest, and 

 seat himself conveniently. The instrument is suspended by 



