GENERAL PATHOLOGY. 27 



disease of the walls, or to overfulness or increased tension, 

 as in congestion. 



Hasmorrhage may also be due to alterations in the quality 

 of the blood, as in purpura haemorrhagica. 



The term epistaxis is applied to bleeding from the nose ; 

 melsena, to bleeding from the bowels; hsematemesis, to 

 bleeding from the stomach; hoematuria, to bleeding from 

 the urinary passages; menorrhagia, to bleeding from the 

 uterus. 



DROPSY. 



Dropsy is due to accumulation of serous fluid in the 

 serous cavities, and in the interstices of the tissues of the 

 body. More or less generally diffused dropsy of the integu- 

 ment is called anasarca. When localized, dropsy is called 

 oedema. Ascites denotes dropsy of the peritoneal cavity ; 

 liydrothorax, of the pleural cavity; hydro-pericardium, of 

 the pericardial cavity ; hydrocephalus, of the ventricles of 

 the cerebrum. Dropsical effusion is a colourless or straw- 

 coloured, alkaline or neutral, clear or turbid watery fluid, 

 having a specific gravity of 1010 to 1015. It holds albumen, 

 salts, and extractives in solution. One of the chief patho- 

 logical causes of dropsy is increased blood-pressure, which 

 accompanies the several forms of congestion, especially that 

 due to mechanical interference with the return of blood by 

 the veins. 



The pressure of the blood may also be increased inde- 

 pendently of congestion, by obstruction to its flow through 

 the capillaries, traceable to alteration of the relationship 

 which exists between the blood in the capillaries and 

 tissues around. Such a condition often accompanies chronic 

 renal disease. 



Dropsy may be local or general. 



Local dropsy is frequently due to mechanical obstruction 



