504 



THE OUTGO OF ENERGY 



opens below into the lung, above into a rubber tube 

 in the wall of which is a small opening, which repre- 

 sents the glottis, and which may be partly or wholly 

 closed by a glass rod. The left manometer shows the 

 intrathoracic pressure, the right manometer the intra- 



Pig. 67. The respiration scheme; about one-third the actual size. 



pulmonary pressure. The normal relations between 

 intrathoracic and intrapulmonary respiration may be 

 reproduced with this apparatus. The pressure changes 

 in forced respiration, obstructed air passages, asphyxia, 

 coughing, sneezing, hiccough, and perforation of the 

 pleura may also be studied. 



