2 74 a c °li c > or a localized blossoming-out in areas once affected by 

 the proteins of bacteria sown into that spot. Wherry con- 

 tinued : 



According to this theory a sensitized animal differs from a 

 normal one only in possessing a mechanism which can more 

 rapidly destroy the foreign protein. The defensive mechanism 

 is not without its disadvantages. . . . When this reaction 

 occurs at the site where bacteria are growing it is advantageous 

 to the parasite, for the local edema furnishes food in solution, 

 dilutes important antibodies, etc. . . . Animals which have 

 recovered from a severe general anaphylactic shock are resis- 

 tant to another dose of the foreign protein for a considerable 

 time and are said to be desensitized. 



Wherry utilized the fact that in many instances "the host 

 becomes hypersensitive to a second parenteral introduction of 

 the poisonous products of the causative agent," to devise a 

 "sensitivity test." Heat-killed bacteria were injected into the 

 skin. If the patient was "sensitive," the spot of injection 

 reddened and swelled up; otherwise nothing happened. 

 Wherry reported how by it he distinguished in a "mixed" flora 

 the particular strain or strains responsible for the constitu- 

 tional symptoms of the particular patient. 



These ill were of the number that make up the heartbreaks 

 of medical practice — "urticaria, angioneurotic edema, spastic 

 and mucous colitis, so-called chronic appendicitis, certain 

 types of chronic arthritis." He could have added others with 

 which he had had long experience — asthma, sinusitis, recur- 

 rent colds, and certain infections of the eye, skin or subcu- 

 taneous tissues. What he said of the matter was that "search 

 for etiologic agents by the use of intradermal tests" had yielded 

 him "suggestive information." Specifically, he had corralled 

 two or three microorganisms out of a farm yard of ten or 

 twelve species, settled upon them as the criminal offenders, 

 had seen to their proper growth upon artificial media, con- 

 verted them into vaccine, and by injection thereof gradually 

 "desensitized" the patient; and so cured him. He allowed suc- 

 cesses of this kind to speak for themselves. More typical of him 

 were such words : 



Occasionally the intradermal test elicits so marked a local reac- 



