232 MORBID STATES OF THE BLOOD, ETC. 



fragments are distributed among the branches below the point 

 of bifurcation. This affords an adequate explanation of multiple 

 embolism in some one part of an organ while the rest is un- 

 affected, as e.g. of a single Malpighian pyramid of the kidney, 

 or a single lobule of the lung. Finally 0. Weber^s researches 

 have established the fact that minute emboli may pass through 

 the pulmonary capillaries to be ultimately arrested in the nar- 

 rower capillaries of the kidneys. 



§ 197. The consequences of embolism, the morbid changes 

 which are produced in the organs whose vessels are plugged, 

 will be more fully discussed in another part of the present work. 

 I may say generally however that the primary and immediate 

 consequence of every embolism is ansemia (ischaemiaj arrest of 

 blood supply), but that this bloodlessness is immediately followed 

 as a rule by extreme congestion. The more complete the ana- 

 stomotic connexion of the plugged vascular area ^vitli neighbour- 

 ing regions, the better is it fitted to play the part of a coecal 

 appendage, a diverticulum of the circulatory apparatus, which is 

 replenished with blood from every side, but which possesses no 

 adequate outflow, so that the tension of the blood in its interior 

 is higher than in all the other capillaries of the body. This 

 secondary hyperjemia may lead to rupture of vessels, to haemor- 

 rhagic infarctions ; in any case the blood stagnates ; it is not 

 renewed and nutrition comes to a deadlock. The consequences 

 of embolism therefore are all essentially bound up with disturbed 

 nutrition; not a few indeed present the characters of true 

 necrosis. (Cf Metastatic abscesses of the lung, the liver, the 

 kidneys, embolic necrosis of bones, yellow softening of the 

 brain, &c.) 



c. Inflammation and Tumours. 



§ 198. The possibility of an inflammation of the blood 

 (hsemitis — Piorri/^, was at one time seriously discussed. The 

 increase in the number of leucocytes which may be shown to 

 accompany leukhamia, caused Bennett in particular to assume 

 that the blood as a whole underwent suppuration. All such 

 theories however must be rejected by us, were it only on the 

 ground that the contrast between blood and parenchyma, between 

 nutriens and nutrieyidumy is indispensable for our conception of 



