STUDIES ON HAEMOLYSIS. 25 



rial. Such occasions are presented by many different diseases. 

 Keeping to the blood, for example, if an individual suffers a con- 

 siderable subcutaneous hemorrhage or one into a body-cavity, or 

 if part of his blood-corpuscles are destroyed and dissolved by certain 

 blood-poisons, the es-ential conditions, just as in an experiment, 

 are given for the reactive formation of substances possessing specific 

 injurious affinities for these blood-cells. The same, however, can 

 apply to other tissues; for every acute atrophy of an organ's paren- 

 chyma can lead to the absorption of cell material and to its conse- 

 quences. The conditions necessary for the development of specific 

 cell poisons may be presented by various circumstances, thus, when, 

 spontaneously or under the influence of arsenic, large lymph-gland 

 tumors are absorbed; when a struma melts and disappears under 

 specific treatmnt; when the white blood-cells, owing to the action 

 of toxins or other substances, are caused to disintegrate; when, 

 owing to certain metabolic or infectious diseases, acute atrophy of 

 the liver ensues, etc. We shall further have to assume that these 

 conditions can be fulfilled, in a wider sense, when, under the influence 

 of certain general diseases, there occurs active dissolution of or- 

 ganized material of any kind instead of atrophy of a single organ. 



It is therefore of the highest pathological importance to determine 

 whether the absorption of its own body material can excite reactive 

 changes in the organism, and what the nature of these changes is. The 

 simplest conditions and those most accessible to experimental study are 

 those which arise on the absorption of blood-cells. But here we face a 

 curious dilemma. If an animal organism, when injected with blood- 

 cells of foreign species, always produces a specific hsemolysin for 

 each of these species, it must surely be following a natural law; and 

 it is improbable that this law which applies in any particular number 

 of cases should be suspended in the case of blood-cells of the same 

 individual. On the other hand, it is not to be denied that the forma- 

 tion of such haemolytic substances w r ould appear dysteological in the 

 highest degree. For example, if, in an individual who has had an 

 extensive haemorrhage into a body-cavity, the absorption of this 

 blood caused the formation of a blood poison which destroyed the 

 rest of the blood-cells, this -would be a phenomenon whose actual 

 occurrence lacks any clinical evidence whatever and one which no one 

 is willing to accept. 



It cannot be doubted that the organism seeks a w r ay out of this 

 difficulty by means of certain regulating contrivances, whose deter- 



