II/KMORRHAGIES. 201 



BOOK IV.OF HJ3MORRHAGIES. 



CHAP. I. OF H^EMORRHAGY IN GENERAL. 



DCCXXXV. In establishing a class or order of diseases un- 

 der the title of Hcemorrhagies, Nosologists have employed the 

 single circumstance of an effusion of red blood, as the character 

 of such a class or order. By this means they have associated 

 diseases which in their nature are very different ; but in every 

 methodical distribution, such arbitrary and unnatural associa- 

 tions should be avoided as much possible. Further, by that 

 management Nosologists have suppressed or lost sight of an es- 

 tablished and well-founded distinction of haemorrhagies into Ac- 

 tive and Passive. 



DCCXXXVI. It is my design to restore this distinction; 

 and I shall, therefore, here, under the title of Haemorrhagies, 

 comprehend those only which have been commonly called Ac- 

 tive, that is, those attended with some degree of pyrexia ; which 

 seem always to depend upon an increased impetus of the blood 

 in the vessels pouring it out, and which chiefly arise from an 

 internal cause. In this I follow Dr. Hoffmann, who joins the 

 active haemorrhagies with the febrile diseases, and have accord- 

 ingly established these haemorrhagies as an order in the class of 

 Pyrexiae. From this order I exclude all those effusions of red 

 blood that are owing entirely to external violence ; and all those 

 which, though arising from internal causes, are, however, not 

 attended with pyrexia, and which seem to be owing to a putrid 

 fluidity of the blood, and to the weakness or to the erosion of 

 the vessels, rather than to any increased impetus of the blood in 

 them. 



DCCXXXVII. Before proceeding to treat of those proper 



