Collected papers . 3 -477 Mean •137 -111 Exp. II, 9. 6. 09. Temperature 54 15° C. 0-25 1 509 444 472 475 475=^0 2-677 — 0-5 1 198 201 199-5 199-5 2-300 1-51 1-0 3 121 86 108 105 35 1-544 1-51 1-5 5 40 54 46 46-6 9-3 •968 1-37 2 0 10 16 18 13 15-66 1-566 •195 1-42 Mean 1*45 256 Disinfection It may therefore be said that with disinfection of B. typhosus by hotwater an approximately logarithmic relation exists between time andconcentration of surviving bacteria, and that any departure is in thedirection of disinfection being quicker at the beginning and slower atthe end of the process than would
Collected papers . 3 -477 Mean •137 -111 Exp. II, 9. 6. 09. Temperature 54 15° C. 0-25 1 509 444 472 475 475=^0 2-677 — 0-5 1 198 201 199-5 199-5 2-300 1-51 1-0 3 121 86 108 105 35 1-544 1-51 1-5 5 40 54 46 46-6 9-3 •968 1-37 2 0 10 16 18 13 15-66 1-566 •195 1-42 Mean 1*45 256 Disinfection It may therefore be said that with disinfection of B. typhosus by hotwater an approximately logarithmic relation exists between time andconcentration of surviving bacteria, and that any departure is in thedirection of disinfection being quicker at the beginning and slower atthe end of the process than would be the case if the agreement Time, minutes Fig. 9. Disinfection of B. typhosus with hot water (Table X).(a) Exp. I at 49° C. {b) Exp. II at 54-15^ C. TABLE XI. Disinfection of B. typhosus with hot water. Exp. I, 2. 6. ( 39. Temperature 5 2°C. Time,minutes Amountof sampletaken,drops Numbers counted on plates (agar) Mean Mean no. of bacteria present in 1 drop disinfection mixture, =N Logjo^ <n K=-t ^°^A^ 0-25 1 204 180 192 192 = iVo 2-28 — 1 1 6 29 20 18-3 18-3 1-26 1-36 2 2 3 0 4 2-33 1-16 •06 1-27 Mean 1-31 Exp. II, 5. 6. 09. Temperature 52-1° C. 0-29 1 576 470 523 523 ^A^o 2-718 — 1 2 189 251 220 110 2041 •95 2 5 91 67 79 15-8 1-199 •89 4 10 18 15 16-5 1-65 •217 •67 Mean ^84 H. Chick 257 (b) B. coli commune. Experiments made with B. coli commune at temperatures from49° C. to 53° C. gave results similar to those with B. tijphosus. Table XII and Fig. 10 express the results of two experiments usingagar plates; Table XIII and Fig. 11 are from experiments made withgelatine plates. The logarithm
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