390 



to wearing corsets the tonic action of the recti is less marked and 

 thus the respiratory excursion of the operculum is greater than in men. 



When the patient lies down this tonic action of the recti is no 

 longer called into play. The sternum is not anchored and therefore 

 the respiratory movement of the operculum is increased in both sexes. 

 These results are in harmony with Mosso's teaching (5). 



In one woman suffering from visceroptosis with associated lack 

 of tone in the recti, the respiratory movement of the operculum was 

 very pronounced, even in the erect posture. 



Since these observations were made Desveknine has published an 

 account of his stethograph which he invented for the purpose of in- 

 vestigating the respiratory excursions of the thoracic operculum (7). 

 Very delicate movements may be recorded by this instrument, but 

 for the purpose in hand rougher measurement proved quite sufficient. 



I thus assured myself that the anterior end of the first rib is 

 by no means a fixed point in respiratory movements and that the 

 influence of the recti abdominis on the anchoring of the manubrium 

 is considerable. As the action of the muscles begins when the child 

 learns to walk and persists throughout life, it seemed possible that 

 the long-continued tonic action of the recti might increase the costal 

 angle (i. e., the angle between the first rib and the horizontal). Hence 

 it seemed advisable to investigate the position of the first rib relative 

 to the vertebral column in patients of all ages. At this stage, how- 

 ever, I met with the difficulty of finding a fixed point from which 

 1 could take measurements. In the cadaver it is easy to measure 

 the angle of tilting which the first rib makes with the horizontal (see 

 Fig. III). But I could not be certain that the position in the body 

 occupied by the first rib when seen in the postmortem theatre is in 

 any way an accurate indication of its average position during life. 

 In every case where I measured this angle I also previously meas- 

 ured the clavicular angle just as I had done in the living. For if 

 in the relaxation of the tissues after death there were any conside- 

 rable alteration in the position of the first rib, there would in all 

 probability be considerable alteration in the position of the clavicle. 

 This is the more likely as neither extremity of the clavicle can be 

 considered to be a fixed point, and therefore the tendency of the cla- 

 vicle to alter in position at death will be greater than that of the first rib. 



Moreover, if relaxation of the tissues should alter the position 

 of the parts concerned then the relaxation of the recti would diminish 



