538 



Dr. P. F. Frankland. 



[June 10, 



Bacillus pyocyaneus in Deep Well-water. 

 Number of Colonies found in 1 c.c. 





Day of 

 preparation. 



3rd Day. 



5th Day. 



8th Day. 





3,900 



Innumerable. 



— 



— 







(Incub.) 







„ 2 



3,900 



Innumerable. 







w 3 



269,000 





432,000 



395,000 







(mcuD.^ 



(Incub.) 



„ 4 



269,000 





422,000 



Innumerable. 



» 5 



262,000 





851 



87 









(Incub.) 



(Incub.) 



» 6 



262,000 





195,000 



227,000 



„ V 



10,000 













» 8 



10,000 













„ 9 



10,000 

















(Incub.) 





(Incub.) 



Bacillus pyocyaneus in Sewage. 

 Number of Colonies found in 1 c.c. 





Day of 

 preparation. 



3rd Day. 



8th Day. 



18th Day. 



No. 1 



29,000 



Innumerable. 



Innumerable. 



547,000 





(Incub.) 



(Incub.) 



(Incub.) 



„ 2 



29,000 



90,500 



Innumerable. 



Innumerable. 



„ 3 



29,000 



116,500 



Innumerable. 



Innumerable. 



The great vitality of this organism is well illustrated by experi- 

 ments No. 1, 2, and 3, with distilled water, in which after fifty-three 

 days there were in each case a great many more colonies obtained 

 than at the outset, although in each case the number was greatly 

 reduced immediately after the inoculation. For experiment No. 5, 

 with distilled water, the number of organisms was in the first instance 

 so largely reduced that on the third day there were no organisms 

 demonstrable even in a whole cubic centimetre, and even on the 

 seventh day the number had only risen to nineteen in that volume. 

 The corresponding sample (No. 4) placed in the incubator multiplied 

 much more rapidly, showing 6200 colonies on the third day and 

 96,000 on the seventh in 1 c.c. 



In the deep well and filtered Thames waters there is abundant 

 ■evidence of extensive multiplication, the only cases (No. 7, 8, and 9) 



