HISTORIC DEVELOPMENT OF IMMUNOLOGY 3 



ing for this purpose in Suffolk and Richmond 

 Park, and there was once a similar tree in Bur- 

 lington County, New Jersey. 



Color is a factor of great moment in folk- 

 healing; red, in particular, which the Chinese 

 and New Zealanders regard as hateful to evil 

 spirits, and other peoples as a heat-producer. 

 Red silken bands, necklaces of coral beads, red 

 pills and red fire, as well as the red coral ring 

 and bells with which the baby cuts its teeth- 

 all have had their superstitious associations; 

 and the virtues of the familiar red flannel cloth 

 worn about the neck for sore throat and whoop- 

 ing-cough were supposed to reside not in the 

 flannel but in the red color. Finsen's red-light 

 treatment to prevent pitting in smallpox was 

 once an ancient folk-belief known to the 

 Japanese. 



The history of the advancement of medical 

 science, however, is the history of the discovery 

 of a number of important fundamental princi- 

 ples leading to new views of disease, to the in- 

 vention of new instruments, procedures, and de- 

 vices, and to the formulation of public hygienic 

 laws all converging to the great ideal of pre- 

 ventive medicine ; and this was accomplished by 



