172 ELEMENTS OF WATER BACTERIOLOGY 



throne and dance before it " he recognizes that the 

 isolation of this organism has its place. " My aim will 

 have been realized," he says, " if I have been able to 

 show that the colon test may be useful under certain 

 circumstances, but that it must be viewed with great 

 caution and that, moreover, not the mere numbers 

 of colon bacilli, but a careful consideration of the local 

 situation and all the circumstances bearing on the special 

 case are absolutely essential to the formation of an 

 opinion." With Prof. Gartner's emphasis on the 

 importance of a sanitary inspection all experienced 

 bacteriologists will certainly find themselves in agree- 

 ment. 



Some of the best French bacteriologists are strong 

 supporters of the value of B. coli as an indicator of 

 pollution. Gautie (1905) holds that the quantitative 

 determination of B. coli is of the highest importance 

 in water analysis; and Vincent (1905), in an excellent 

 review of the subject, gives strong reasons for main- 

 taining the same position. He finds B. coli absent 

 from spring and well-waters of good quality and present 

 in polluted water in proportion to its pollution. He 

 concludes finally that water containing B. coli in .1 to 

 i.o c.c. is unfit to drink, while if the organism is found 

 in 1.0 to 10. o c.c. it is of doubtful quality. 



In Portugal too the trend of opinion is strongly in 

 favor of the colon test — the Anglo-American procedure, 

 as it is called in the publications of Dr. Bettencourt 

 and his associates (Ferreira, Horta and Paredes, 1908*). 



Altogether the evidence is quite conclusive that the 

 absence of B. coli demonstrates the harmlessness of a 



