PARENTERAL DIGESTION 71 



this wave of toxicity, but adjust every condition 

 to the best of my ability, I have been unable to 

 chart it. It is to be hoped that some wiser man 

 with more perfect control of the conditions of 

 his experiments will solve this question. I am 

 willing to leave it to those braver than I to 

 try on human beings such poisonous mixtures 

 of bacterial proteins as phylacogen. 



I have stated that I am not yet ready to give 

 up the idea that the parenteral introduction of 

 foreign proteins produces specific alterations in 

 the blood. I cannot do so, so long as I have the 

 evidence supplied by the specificity of agglu- 

 tination and precipitin reactions. We may 

 have no proof that these are due to the develop- 

 ment of specific proteases, but whatever their 

 action it is within certain limits specific. Some 

 years ago with my assistants I published the 

 results of work which I interpreted as demon- 

 strating the elaboration of specific proteases in 

 sensitized anim'als. The results were all so 

 clean cut and uniform that they were convinc- 

 ing to me at least. I will give a brief abstract : 

 (1) One milligram of egg-white incubated at 

 37, for thirty minutes in 5 c.c. of the serum or 

 organ extract of unsensitized guinea-pigs is 

 without effect when injected into the heart of 

 another unsensitized guinea-pig. (2) Like re- 



