1080 



THORAX. 



the diaphragm acting as one muscle, makes 23 

 mobile regions for respiration. 



The respiratory movements of health may 

 be classed as costal and abdominal. The cha- 

 racter should be established by the order in 

 which they follow each other. In health the 

 walls of the thorax and the floor do not 

 dilate simultaneously but consecutively. The 

 character of " the breatliing'" cannot always be 

 told by the eye, but it can always be deter- 

 mined by the touch. If we stand behind a 

 patient, when seated and leaning against the 

 back of the chair or against our person, and 

 pass the right arm over the shoulder, extending 

 it over the anterior part of the chest, until 

 the hand rests upon the abdomen over the 

 umbilical region, we command a delicate index 

 of the breathing movements. It will then be 

 found, that in ordinary male breathing the ab- 

 domen first bulges outwards ; the ribs and 

 sternum nearest the abdomen gently follow 

 this movement, until the motion, like a wave, 

 is lost over the thoracic region. The undu- 

 lation commences at the abdomen. This is 

 aoaomina, or diaphragmatic respiration. We 

 here have costal motion, but as the ribs moved 

 second it is not called costal breathing. 



In costal breathing the upper ribs move first, 

 and the abdomen second. This is the ordinary 

 breathing in women. 



All difficult, sudden, and extraordinary 

 breathing is costal ; we at such times direct 

 all our power towards the apex of the thorax, 

 first expanding that region, and gradually those 

 below it. 



When we determine the order of breathing 

 by the sight, we must be careful to take the 

 position of the body into account. If the pa- 

 tient be recumbent (supine), we may notice 

 extensive costal motion, and, indeed, it may 

 be true costal breathing ; but place the pa- 

 tient erect, and the breathing may be diaphrag- 

 matic. When recumbent, all the motion is 

 thrown forwards, the natural backward and 

 lateral motion of the ribs being prevented ; 

 and so sensitive are the breathing movements 

 to impediments, that they may either take a 

 reverse action, or all the motion being thrown 

 forwards, will give a preternatural movement 

 of the ribs, which may be mistaken for costal 

 respiration. 



Profile vieiv of the breathing movements 

 (a) Ordinary breathing (Male). Fig. 71 1 was 

 obtained by tracing the shadow of a man on 

 paper. The back was fixed, so as to throw 

 all the movement forwards. The anterior 

 black, continuous line represents the ordinary 

 breathing. This line is thicker over the ab- 

 domen than elsewhere. The anterior margin 

 of this line indicates the boundary of the ordi- 

 nary inspiration, and the posterior margin the 

 boundary of the ordinary expiration. 



(Female). This is represented by the 

 anterior continuous line \njig.7l2., in the same 

 manner as shown in the male. This line in 

 the female is broadest over the sternum, and 

 narrow over the abdomen. The movement 

 over the abdomen of the female is so small, 

 that the number of the respirations cannot 



Fig. 711. 



Respiratory Movements. Male. 

 Deep inspiration, dotted line ; ordinary state, 

 continuous line; deep expiration, anterior margin 

 of the shade. 



be counted by the hand resting on that region 

 as it can be on the male. The question of 

 why women breathe costal, and men abdo- 

 minal, we cannot pretend to answer. We 

 doubt its being caused by any tight costume, 

 for we found the same to exist in twenty-four 

 girls between the ages of eleven and four- 

 teen, none of whom had ever worn any tight 

 dress. This peculiarity may be a reservation 



Fig. 712. 



Respiratory Movements. Female. 



Inspiration, dotted line. Ordinary, continuous 

 line. Expiration, anterior margin. 



