THE CHEST 



171 



pleura, is very smooth and under normal conditions is 

 made slippery by means of a fluid very similar to the 

 synovial fluid of the joints. The two pleural surfaces, 



Superior vena cat 



Sternum 



Outline of heart (auricles) 

 Boundary between auricle 

 and ventricle 



Carotid artery 

 vein 



Arch of aorta 

 Outline of heart (ventricles) 



Lungs 

 Top of diaphrag 



Liver- 

 Call bladder. 



Lungs 



Portion of heart not, 



covered by lungs 

 Stomach 



Large intestine 

 Small intestine 



FIG. 101. Chest, showing position of organs. 



which normally are in contact, are thus made to slip 

 easily over each other during the enlargement and reduc- 

 tion of the chest cavity in the movements of breathing. 

 The inflammation and roughening of these surfaces are 

 what give rise to the discomfort and pain of pleurisy. 

 As a result of pleurisy, the surfaces sometimes grow 

 together, so that the lungs can no longer slip up and 

 down. 



Relation of lungs to chest cavity. Under the nor- 

 mal conditions of life, the lungs fill all the cavity of the 



