PERSONAL APPEARANCES IN HEALTH AND DISEASE. 53 



of expansion takes place every time we take a breath, 

 and if the breathing be forced and hurried, other and 

 more powerful muscles which have attachments to ribs, 

 act on these bones and increase the area of their move- 

 ment. But as the ribs are (the six upper directly and the 

 three following indirectly) connected with the sternum or 

 breast bone, this bone is, at the same time as the ribs are 

 raised, thrust bodily forward. There is thus an enlarge- 

 ment of all the diameters of the chest, the vertical, the 

 transverse, and the antero-posterior ; the cavity is in- 

 creased in length, in width, and in depth from before 

 backwards. When, on the other hand, the lungs are 

 completely emptied of air, that is, at the close of a number 

 of forced expirations, the chest is narrowed in all those 

 diameters, and its circumference is proportionately less. 

 Contrasting the position of the ribs in the two conditions, 

 note that at the end of a full inspiration they have a 

 nearly horizontal direction, whereas at the close of a 

 de^ep expiration they are sloped downwards and forwards, 

 and are therefore more Vertical. So that, in fact, the 

 chest looks longer but narrower when its lungs are less 

 exp^ided than when they are fully distended. Now it 

 is not at all uncommon to meet with people the confor- 

 mation of whose chest approaches what may be called the 

 " inspiratory type," and quite, if not more common those 

 in which it is rather of " expiratory type." The small, 



