86 THE MICROSCOPE. June, 



foundation on wliich rests that structure of modern 

 genius — serum-therapy. 



Workers have been unceasing in their efforts to dis- 

 cover protecting agents for other infectious diseases. 

 The development of bacteriological science in the past 

 twenty years has shown the essential etiological factor 

 of many of these maladies. It was evident that in every 

 disease in which a past attack protected the patient against 

 renewed infection, there was exerted on the tissues an 

 influence, either by the morbific agent or its products, 

 which rendered it difficult or impossible for the germs 

 to again flourish. Pasteur was the first to procure im- 

 munity from certain animal scourges, as anthrax and fowl 

 cholera, using the method of inoculating them with 

 attenuated cultures of the organic causative agent of the 

 disease. 



The second method of bacteric-therapy is entirely 

 different. Behring discovered that in diphtheria and 

 tetanus, substances that destroyed or counteracted the 

 poison were found in the blood of immunized animals, 

 and by these substances a preventative vaccination, as 

 well as a cure of those already attacked, may be affected. 

 These substances were found to be as specific as the liv- 

 ing organism causing the disease and the poisons produced 

 by them. The doctor then gave the various facts or 

 points noted by Aronson, upon which facts this system 

 of serum-therapy is founded, also Behring's summing up. 

 Among these points of general interest to the public, it 

 may be mentioned that larger doses of the anti-toxine 

 are never injurious, but on the contrary can only be beni- 

 ficial ; that each blood anti-toxine is immunizing and 

 curative only for one infection, and that as anti-toxines 

 are soluble bodies, they may eventually be produced 

 outside the living body, or even be compounded synthet- 

 ically. 



