440 TUBERCULOSIS AND ITS PREVENTION 



grown on his serum-agar; the inoculated animals contracted 

 tuberculosis and died. 



He decided to try one more experiment. He wondered how 

 people contracted tuberculosis, and thought that they had prob- 

 ably inhaled some of the dust particles of which Pasteur had 

 spoken, or possibly were infected by droplets which tubercular 

 people scattered in the air when they coughed. He sprayed 

 bacilli into the air breathed by certain animals. The animals 

 became tubercular and died. 



The method of investigating an unknown disease that Koch 

 used in 1882, is still being used to-day. His method is commonly 

 known as Koch's postulates which are : (1) isolate the probable 

 germ from the diseased organism ; (2) grow the germs in an arti- 

 ficial media; (3) transfer the germs from the culture to an 

 organism and notice whether they will produce the disease; 

 (4) obtain some of the germs from the second organism and iden- 

 tify them. From Koch's investigation, dates the beginning of the 

 triumph of bacteriology. 



Koch reported his findings before the Physiological Society, in 

 Berlin, in March, 1882. The most brilliant men of science in 

 Germany were there. There was no word of criticism against 

 his work ; it was too thorough and convincing. The news of his 

 discovery spread rapidly, and the entire world soon learned of his 

 work and his methods of investigating diseases. 



Edward Livingston Trudeau. While Koch was investigating 

 the cause of tuberculosis, there was a man named Trudeau living 

 in the United States. . He was taking care of a tubercular brother 

 whom he bathed, fed, and even slept with. His doctor warned 

 him not to open the windows as it was bad for the brother's cough. 

 The brother finally died. 



Trudeau then studied medicine, became a doctor, but did not 

 practice long, before he realized that he had tuberculosis. Like 

 all people of his day, he thought tuberculosis meant certain death. 



