502 Profs. Percy Fraukland aud Marshall Ward. 



From the above tables it will be seen that in the steam sterilised 

 Thames water the typhoid bacilli underwent no -multiplication, but, on 

 the contrary, steady diminution, being last discovered on 20.11.1893, or 

 thirty-two days after their first introduction. 



In the Thames water, sterilised by filtration, their disappearance was 

 far more rapid, for they were no longer discoverable eleven days after 

 their introduction, and they had doubtless died off even before this. 

 These results entirely confirm my previous experiences recorded on 

 p. 464, and the confirmation is of the more importance, as the filters 

 used in the two cases were entirely different ; thus whilst that used on 

 the former occasion was a Chamber-land cylinder of porous porcelain, 

 the one used in this latter instance was a small porous cylinder con- 

 structed of infusorial earth. These infusorial earth cylinders are 

 much more porous than the porcelain ones, and pass the water far 

 more rapidly. 



