1879.] of the Pregnant Uterus and its Contents in Woman. 495 



In other words, these contractions of the uterus act as a kind of sup- 

 plementary heart to these fluids." 



To this force I have now to add the effect of the respiratory move- 

 ments on the gravid uterus and its contents. Any one who places his 

 hand on the abdomen of a pregnant woman over the centre of the 

 uterus will he conscious of the projecting forward of the uterine wall. 

 But I presume this has been supposed hitherto to be merely the pro- 

 jection of the uterus en masse. Admitting that a slight portion of the 

 movement is owing to that, I shall endeavour to show that the much 

 greater portion of the movement is due to the bulging out of the walls 

 by the downward pressure on the fundus during inspiration. This is 

 best demonstrated by a cardiograph constructed with a button tam- 

 bour, supported by three legs, capable of being adapted by screws to 

 the proper length ; these should be as far apart as possible, four inches 

 or so. The patient should be placed on her back, and the tambour 

 tied gently on to the abdomen by a tape passed round the back. The 

 drum being set revolving, the respiratory movement is traced. The 

 respiratory markings are very regular considering the circumstances, 

 interrupted at irregular intervals by the foetal movements, coughing, 

 and other movements of the body. 



Normal Respiratory Wave oyer Pregnant Uterus. The s«t&-readings depending 

 probably on arterial impulse of mother ; and of the foetus. 



Now, it is clear that the readings express the difference of elevation 

 of the uterine wall between the tambour button and the circle enclosed 

 by the legs ; in fact, the amount of the bulging of the wall within 



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