PHTHISIS. 315 



edge of the trapezius, an inch and a half above the clavicle ; 

 thence the curve passes downwards and inwards towards the 

 clavicular attachment of the sternomastoid. The pulmonary 

 resonance above the clavicle is obtained by direct percussion 

 downwards upon the sloping anterior surface of the apical part 

 of the lung ; this surface lies under cover of Sibson's fascia and 

 the scalene muscles. Even in health a flatness or deficiency in 

 percussion resonance may be expected on the right side in most 

 individuals, possibly because of the greater muscular develop- 

 ment on this side of the body. At the right apex, too, the 

 breath sounds are louder, the expiratory murmur more audible 

 and, hence, apparently prolonged, the vocal resonance more 

 marked, and the vocal fremitus more easily appreciated. In 

 women and children the breath sounds at this apex may even 

 possess a bronchial quality. There is an anatomical basis for 

 these differences. The apex of the right lung is closely applied 

 to the side of the trachea, owing to the deviation of that tube 

 to the right ; consequently tracheal sounds are easily communi- 

 cated to the upper part of the right upper lobe, whereas on the 

 left side the oesophagus in part, the left subclavian and common 

 carotid arteries and the aortic arch all intervene between the 

 trachea and the lung. In addition, the right main bronchus is 

 rather larger than the left and sooner gives off the branch to the 

 upper lobe. 



It is important to bear in mind the positions in which tuber- 

 culous deposits may be expected in the lungs and the relations 

 these spots bear to the chest walls. The primary and oldest 

 lesion is usually found in the upper lobe, about one or one and 

 a half inches below the extreme apex, and rather nearer to the 

 postero-external aspect than any other part of the surface of the 

 lung. From this focus the disease spreads directly backwards, 

 giving rise to signs in the supraspinous fossa, and also down- 

 wards and forwards along the anterior aspect of the upper lobe, 

 causing indications of its presence by abnormal physical signs 

 above the clavicle or in the first, second and third intercostal 

 spaces about an inch and a half away from the sternal edge. 



