ANTI-ANAPHYLAXIS OF ANIMALS 145 



blood but under the skin, resulted in the formation of indur- 

 ated edemas at the point of inoculation. Arthus found at 

 the same time that animals sensitized by a serum also become 

 hypersensitive to peptone or to gelatin, though to a lesser 

 degree; in short that the anaphylactic reaction is not always 

 an exclusively specific one. 



Marfan confirmed these experiments by the observation 

 of "Serum Disease" in children repeatedly injected with 

 antidiphtheritic (horse) serum. 



In a series of most interesting experiments, Hamburger 

 and Moro showed that a heterologous serum injected into 

 the veins of an animal continues to circulate in this animal's 

 blood up to the appearance of the specific antibody. It is at 

 this moment that the incubation period ends, and that the 

 animal becomes hypersensitive to a new injection of the same 

 substance. 



Besredka determined that this incubation period was 

 longer as the quantity of heterologous serum injected was 

 greater, and Friedberger's researches completed this series of 

 experiments by showing that, if an animal be injected repeat- 

 edly with the same serum in non-pathogenic doses, the incu- 

 bation period becomes progressively shorter, which means 

 that the formation of the antibody takes place progressively 

 more rapidly. 



These researches, therefore, allowed certain elements of the 

 problem to be defined, but at the same time, they brought 

 out others of a complicating nature. 



These facts as well as the observations of the unfortunate 

 accidents in the preparation of antibacterial sera already 

 caused the prediction that the phenomenon of anaphylaxis, 

 its causes, nature and mechanism could be regarded, from a 

 different and broader point of view than that which inspired 

 Richet in his experiments and in the interpretation of their 

 results. 



ANTI-ANAPHYLAXIS AND THE IMMUNIZATION OF 

 ANIMALS. 



The discovery of antidiphtheritic serum naturally sug- 

 gested the idea of trying in the same way to obtain curative 

 10 



