Report on the Bacteriology of Water. 395 



PART II. 



" The Behaviour of the Typhoid Bacillus and of the Bacillus 

 Coli Communis in Potable Water." By PERCY FRANKLAND, 

 Ph.D., B.Sc. (Lond.), F.R.S., Professor of Chemistry in 

 Mason College, Birmingham, assisted by J. R. APPLEYARD, 

 F.C.S. 



It has already been pointed out in the previous Reports that the 

 only two zymotic diseases which have heen conclusively proved to be 

 communicable, and frequently communicated by drinking water, are 

 Asiatic cholera and typhoid fever. The behaviour in water of the 

 particular micro-organisms which are almost universally credited 

 with the power of exciting these specific maladies is obviously, there- 

 fore, one of the most interesting and important questions in the 

 whole domain of the hygiene of water supply. 



Inasmuch as Asiatic cholera is, fortunately, only an occasional 

 visitor of these islands, or, indeed, of the continent of Europe, the 

 investigation of this question with regard to this disease is certainly 

 of less immediate consequence than is its investigation with regard 

 to typhoid fever, which we have always with us, and which claims 

 such a large number of victims annually from amongst our popula- 

 tion. 



In the present Report I have, therefore, endeavoured on the one 

 hand to summarise briefly what has already been done by others 

 towards the elucidation of this subject of the behaviour of the 

 typhoid bacillus in water, whilst on the other hand I have recorded 

 those experiments which I have myself conducted with a view to 

 extending the knowledge of this matter in general, and in .respect 

 to the conditions of water-supply pertaining to this country in par- 

 ticular. 



Our information concerning the behaviour of the typhoid bacillus 

 in water is of essentially two different kinds ; firstly, this bacillus 

 has on a number of occasions been discovered with more or less 

 certainty in waters which were actually being used for domestic pur- 

 poses, and to which it had therefore gained access unintentionally 

 and in the natural course of events ; secondly, the bacillus has been 

 purposely introduced into various waters in which its subsequent fate 

 has then been traced by experimental observation. It will be con- 

 venient to consider these two different kinds of information separately. 



VOL. LVI. 2 E 



