22 
Transactions Texas Academy of Science. 
and it at once opened an entirely new and promising field for inves- 
tigation. 
December 3, 1890, in No. 49 of the Deutsche med. Wochenschrift , 
Behring and Kitasato published an article, “Ueber das Zustande- 
kommen der Diphtherie-Immunitat und der Tetanus-Immunitat 
bei Thieren,” in which the statement is made that: “The blood 
of tetanus-immunized rabbits possesses the property of destroying 
tetanus toxin. This is possessed by the extravascular blood, and 
is the cell free serum.” They showed that the blood serum of non- 
immunized animals did not possess this antagonizing action, and 
that the prepared serum was of therapeutic value. Ogata and 
Jasuhara 32 proved that blood serum from an animal naturally 
immune contained substances which, when injected into mice, con- 
ferred upon them the same type of immunity. Tizzoni and Cat- 
tani 33 (1891) found that the quantitative protective value of the 
blood serum of animals naturally immune to tetanus (the dog, for 
instance) could be greatly increased by repeated injections of grad- 
ually increasing amounts of tetanus-toxin; and that such serum 
possessed decided therapeutic value when inoculated into animals 
suffering from tetanus. This line of investigation has been greatly 
extended and enriched by Behring, Roux, Koch, Yersin, Haffkine, 
Pfeiffer, Buchner, Sanarelli, Ehrlich, and others, and as a result, 
there is to be f ound in the open market today a variety of antitoxin 
sera, such as antidiphtheritic, antitetanic, Marmoreck’s antimycotic, 
antipneumococcic, antibubonic, antirhabic, yellow fever, etc. 
March 20, 1896, Professor Thomas R. Fraser, M. D., at the Royal 
Institution of Great Britain, presented a very important contri- 
bution on “Immunisation Against Serpent’s Venom, and the Treat- 
ment of Snake-bite with Antivenene,” in which, for the first time, 
the quantitative relation between the “toxic” and the “anti” sub- 
stance is shown. The contribution is rich in splendidly martialed 
experimental evidence which leads the author to the logical con- 
clusion : that so far as snake venom is concerned, the antidotism of 
the “antivenene” is not the result of physiological reaction, is not 
due to phagocytic action, nor to the “resistance of tissues”; but 
“as I have already pointed out, a chemical theory, implying a reac- 
tion 'between antivenene and venom, which results in a neutraliza- 
tion of the toxic activities of the venom, is entirely compatible with 
the observed facts.” 34 
Another significant fact of chemical importance observed by 
Fraser is, that in carrying out the immunizing process, “the satura- 
tion point of the blood for antivenene is reached before the possible 
maximum non-fatal dose of venom has been administered.” The 
