EXPERIMENT STATION BULLETINS. 



3uy 



Bacterial Counts. 

 In 72 hours. 



Culture le— 1,000,000,000. 

 Culture le + Ij— 1,300,000,000. 

 Culture Ij— 111,000,000. 



COMBINATION If AND Ij. 



Dilutions employed for inoculating milk flasks. 



Culture If 1 : 10,000 



Culture Ij 1 : 1,000,000 



Number of bacteria, If, introduced into milk flask If = 435. 

 Numbei- of bacteria, Ij, introduced into milk flask Ij = 765. 

 Number of bacteria, If and Ij, introduced into milk flask If + Ij = 435 f 765 = 1200 



Changes in milk flasks apparent to eye. 



Milk flask cultures prepared Friday, 9 a. m. 



30 hours after inoculation, Saturday, 3 p. m. 



If — no change. 



If + Ij — litmus reduced at bottom. 



Ij — litmus reduced at bottom. 

 49 hours after inoculation, Sunday, 10 a. m. 



If — no change. 



If + Ij — litmus reduced at bottom. 



Ij — litmus reduced at bottom. 

 77 hours after inoculation, Monday, 2 p. m. 



If — no change. 



If + Ij — litmus reddened. 



Ij — litmus reddened. 

 101 hours after inoculation, Tuesday, 2 p. m. 



If — no change. 



If + Ij — litmus reddened and reduced at bottom. 



Ij — litmus reddened and reduced at bottom. 

 121 hours after inoculation, Wednesday, 10 a. m. 



If— no change. 



If + Ij — curded. 



Ij — curded. 



Acid developed during changes. 



Time after inoculation. lirs. 30 hrs. 49 hrs. 



Culture If 18° 21° 20° 



Culture If + Ij 18° 24° 24° 



Culture Ij 18° 24° 24° 



Bacterial Counts. 

 In 101 hours. 



Culture If— 5,710,000 . 

 Culture If + Ij-452;000,000. 

 Culture Ij— 453,000,000. 



COMBINATION Ig AND Ij. 



Dilutions employed for inoculating milk flasks. 



Culture Ig 1 



Culture Ij 1 



100 

 10,000 



Number of bacteria, Ig introduced into milk flask Ig = 44,800. 

 Number of bacteria, Ij, introduced into milk flask Ij == 48,100. 



Number of bacteria, Ig and Ij, introduced into milk flask Ig + Ij = 44,800 + 48,100 

 = 92,900. 



