512 AUSCULTATION. 



(a) Right side. In the superior region a bronchial sound 

 is heard immediately behind the shoulder, on a level with 

 the tenth rib. It diminishes in intensity to the twelfth, 

 where it gives place to the vesicular. Behind this the vesi- 

 cular sound becomes gradually feebler to the seventeenth rib, 

 where it is entirely lost. In the median region, and where 

 the limb is carried forward, a distinct vesicular sound may be 

 heard over the fifth and four following ribs ; from the ninth 

 backwards it diminishes in force, and is altogether lost over 

 the sixteenth. In the inferior region, where the limb is 

 carried forwards, and the ear or stethoscope applied close 

 above the elbow, the vesicular murmur is well marked over 

 the fourth, fifth, sixth, and seventh ribs, behind which it 

 decreases in pitch to the tenth, where it is entirely lost. 



(6) Left side. The superior region differs in no respect 

 from that of the right. The median region gives a well- 

 marked vesicular murmur over the fourth, fifth, and sixth 

 ribs, where the base of the heart is covered only by a thin 

 portion of lung ; the sound is more intense over the seventh, 

 eighth, and ninth ribs, from which to the sixteenth it gradually 

 diminishes. In the lower region over the fourth, fifth, and 

 sixth ribs, the sounds of the heart only are heard ; a respira- 

 tory murmur is heard over the seventh and eighth ribs, and 

 diminishes gradually from the latter to the tenth. 



Superadded natural sounds may be occasionally heard in 

 the middle and lower regions, and especially towards their 

 posterior parts. These are of a rumbling or gurgling nature, 

 and depend on the movement of matters contained within 

 those abdominal viscera, which lie close behind the diaphragm. 

 They may be distinguished from abnormal thoracic sounds 

 by their extreme irregularity, and by their bearing no relation 

 to the rythm of the respiration. 



