268 Dr. C. Bolton. Dropsy produced by [Dec. 19*, 



In order to examine the immediate effects upon the circulation of the* 

 blood, Starling produced his uncompensated condition of the circulation by 

 introducing oil into the pericardium, which brings about precisely the same- 

 immediate results as any other condition interfering with the diastolic filling 

 of the heart. He, however, registered the venous pressure in the limb by 

 means of a plethysmograph instead of by the direct introduction of a cannula 

 into a vein of the foot. The result was that he obtained a contraction of the- 

 limb, which he interpreted as indicating a fall of venous pressure. I have- 

 already pointed out in my paper that this contraction was an indication of 

 the vaso-motor constriction, which occurs as the result of asphyxia of the- 

 vaso-motor centre. If the venous pressure be taken by means of a cannula 

 inserted into a vein of the foot, it is quite easy to demonstrate at once a rise* 

 of venous pressure in that part, whether the pericardium be filled with oil 

 (see Eef. 1, experiment) or constricted by means of stitches (Kef. 1), or whether 

 the inferior vena cava be obstructed (see Kef. 1, experiment). I, moreover,, 

 showed that it was impossible to keep up the high venous pressure by the 

 injection of salt solution so as to produce hydremic plethora. This is owing 

 ' to the ready distensibility of the veins and the increased activity of the 

 excretory glands. 



The results of my experiments were, therefore, antagonistic to Starling^ 

 theory of hydremic plethora, and I maintained that passive oedema was 

 primarily due to malnutrition of the capillary ivall, raised capillary pressure 

 playing no actual part in its production. 



The present investigation was undertaken from three points of view : — 

 (1) To confirm my previous results by employing a different method. (2) To 

 discover a more easy method of obstructing the venous flow into the heart, 

 and one which admitted of different degrees of obstruction, which could be 

 accurately measured. (3) To bring the results of general venous obstruction 

 into line with those of local venous obstruction, in order to discover thfe 

 common principle underlying both. 



The subject will be treated of under the following headings : — 



1. Method. 



2. Effects of obstruction of the superior vena cava : — 



(a) Upon the production of dropsy. 



(b) Upon the circulation of the blood. 



3. Effects of obstruction of the inferior vena cava : — 



(a) Upon the production of dropsy. 



(b) Upon the circulation of the blood.. 



