1912.] VAUGHAN— THE PROTEIN POISON. 213 



This also explains the beneficial effects that undoubtedly have been 

 obtained by the various vaccines now so widely and often so unin- 

 telligently used. 



I wish to suggest that the exanthematous diseases may be ex- 

 plained by the fact that the foreign proteins of certain diseases are 

 deposited in the skin, and that this tissue is the site of the destruction 

 of the foreign body. I may say in support of this that we have 

 repeatedly injected egg-white into the ear vein of rabbits. After 

 varying periods of time we have shown by sensitizing animals with 

 blood taken from the heart that the egg-white has wholly disap- 

 peared from the circulating blood of the rabbit. Later it can be 

 shown that this egg-white has been deposited in the skin, in the 

 kidney, in the brain, and in various other organs of the rabbit. It 

 seems to me that our work upon the protein poison furnishes us 

 with facts, by means of which we are able to explain many of the 

 phenomena of immunity and of disease. 



