304 PRACTICE OF PHYSIC. 



may be properly supposed to be haemorrhagies of the arterial 

 kind ; but it is probable that the stomach is also liable to hae- 

 morrhagies of the venous kind (DCCLXVIII.)- 



In the records of physic, there are many instances of vom- 

 itings of blood, which were accompanied with a tumefied spleen, 

 which had compressed the vas breve, and thereby prevented the 

 free return of venous blood from the stomach. How such an 

 interruption of the venous blood may occasion an haemorrhagy 

 from either the extremities of the veins themselves, or from 

 the extremities of their correspondent arteries, we have explained 

 above in DCCLXIX. ; and the histories of tumefied spleens 

 compressing the vasa brevia, afford an excellent illustration and 

 confirmation of our doctrine on that subject, and render it suf- 

 ficiently probable that vomitings of blood often arise from such 

 a cause. 



MXXVIII. It is also possible that an obstruction of the 

 liver resisting the free motion of the blood in the vena porta- 

 rum, may sometimes interrupt the free return of the venous 

 blood from the vessels of the stomach, and thereby occasion a 

 vomiting of blood ; but the instances of this are neither so fre- 

 quent, nor so clearly explained, as those of the former case. 



MXXIX. Besides these cases depending on the state of the 

 liver or spleen, it is very probable that other haemorrhagies of 

 the stomach are frequently of the venous kind. 



The disease named by Sauvages, Melaena, and by other 

 writers, commonly termed the Morbus Niger (DCCLXXL), 

 consisting in an evacuation either by vomiting or by stool, and 

 sometimes in both ways, of a black and grumous blood, can 

 hardly be otherwise occasioned, than by a venous haemorrhagy 

 from some part of the internal surface of the alimentary canal. 



It is indeed possible, that the bile may sometimes put on a 

 black and viscid appearance, and give a real foundation for the 

 appellation of an Atra Bilis : but it is certain that instances 

 of this are very rare ; and it is highly probable, that what gave 

 occasion to the notion of an Atra Bilis among the ancients, was 

 truly the appearance of blood poured into the alimentary canal 

 in the manner I have mentioned ; and which appearance, we 

 know, the blood always puts on, when it has stagnated there for 

 any length of time. I suppose it is now generally thought that 



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