32 THE PHYSIOLOGY OF THE ADRENALS. 



and the total pressure exerted on the interior of the latter" 

 being "equal to the area multiplied by the pressure per unit 

 of area," a centrifugal display of force occurred which far 

 surpassed the resistance of the cask, and it had to yield. The 

 hydraulic press, by means of which the hand of a child can 

 break a steel rail, is based upon this principle. 



These principles prevail in the human organism precisely 

 as they do elsewhere in Nature. In the large vascular trunks 

 of the abdomen, abdominal and thoracic viscera, etc., we have 

 closed channels typifying the cask; in the narrow muscular 

 vessels leading to them we have a multitude of conduits por- 

 traying the glass tube. Finally, we have the aggregate of press- 

 ure of millions of contractile, resilient capillary vessels con- 

 taining a mass of blood (so great in comparison to the larger 

 vascular structures that these have been considered as sub- 

 sidiaries to the capillary system) to represent the gobletful 

 of water with which Pascal indirectly caused explosion of his 

 cask. That we have ample power to account for the symptoms 

 mentioned is evident. It also accounts for suprarenal haem- 

 orrhage when violent toxaemia is present. The rich vascular 

 supply of the organs is well shown in the annexed colored plate 

 prepared by J. M. Flint in the course of an exhaustive study 

 of their anatomy, and published in the Johns Hopkins Hospital 

 Reports, two years ago. 



Obviously the application of this principle is subject to 

 limitations which the volume of blood accumulated in the ves- 

 sels of the trunk impose. Admitting, for purposes of illustra- 

 tion, that all the blood of the organism has been forced into 

 the interior of the body, its mass represents a fixed area which 

 the various internal structures must furnish. Thus, while the 

 large vascular trunks bear the brunt of the pressure, all the 

 neighboring organs, including their capillaries, become en- 

 gorged in proportion as the quantity of blood added to their 

 normal contents is great. In other words, the blood accom- 

 datcs itself to any room it can find after the larger vascular 

 trunks are engorged, whether it be in a blood-vessel or a viscus. 

 Thus, Boinet, 69 in 45 of his 59 decapsulated rats, found hacm- 



69 Boinet: Gazette des H6pitaux, July 20, 1899. 



