OF ALBUMINURIA. 7 



being surrounded on all sides but one by the firm 

 unyielding tissue of the membrane, can only relieve 

 itself by effusion in that one direction, and 011 that 

 point therefore the whole force of the distending 

 pressure will act. The contractility of the capillaries 

 is soon exhausted, and the impulse still continuing 

 albuminous effusion takes place. In some instances 

 the fluid thus poured out, though in considerable 

 quantity, has contained so much fibrine, and retained 

 so much of the vital property of the blood, as to 

 coagulate spontaneously when removed from the 

 body after death : in ordinary cases it is capable of 

 organisation, and forms adhesions. When the in- 

 flammation is chronic, or the congestion less intense, 

 the effusion proceeds more slowly, contains less 

 albumen, and more nearly resembles the products of 

 inflammation of the mucous membranes. These 

 latter are looser in their texture, their vessels com- 

 paratively large and numerous, and the porous coats 

 of the capillaries more lax, so that transudation takes 

 place more readily through them. When an in- 

 creased quantity of blood is determined to the vessels 

 of a mucous tract, which had been previously in a 

 healthy state, the immediate effect is a suppression 

 of their secretion, from the capillaries contracting at 

 first on the application of their stimulus. But as 

 they soon begin to yield to the distending force, and 

 become relaxed, the thinner portion of the contained 

 blood escapes in the form of a copious watery dis- 

 charge. In ordinary inflammation this discharge 

 gradually diminishes in quantity and increases in its 

 consistence, probably from its slower secretion and 



B 4 



