404 



Journal of Agricultural Research 



Vol. m, No. s 



/«5-v=: /30' /ss' Z'^o" /v^" -/so" /ss° 

 s/.y'c. s-^s' s^s" €0" e^.e' ess" ee.3* 



Fig. I . — Curve showing results of heating cultures of colon bacilli for 30 minutes at various temperatures. 



Table II. — Variation in the ability of colon bacilli to survive pasteurization for 30 

 minutes at 62.8° C. (145° F.) 



Number of heating. 



GV 



HO 



HP 



IF 



IJ 



IL 



IN 



IS 



lY 



MF 



MT 



NV 



Total cultures . . . 

 Positive 



First. 'Second. 



+ + ! +- 



+ - 



+ ■ 

 + • 

 + - 

 + - 

 + - 

 + - 

 + - 

 + - 

 + - 

 + - 



Third. Fourth. 



+ - 



+ - 



+ - 



+ - 

 + + 

 + - 



+ + 



+ + 

 + + 



+ - 

 + - 

 + 



+ - I +- 



Fifth. 



• 12 I 

 12 1 



12 

 4 



+ - t + + 



+ - 1 -- 



+ + 



+ - 



+ - 



+ - 



+ - 

 + + 

 + - 

 + - 



+ - 



Summao'. 



Both 

 tubes 



Both 

 tubes 



12 

 6 



12 



9 



12 

 O 



One 

 tube 

 + and 

 one 

 tube 



