BACTERIOLOGY AND WATER 113 



to three hours. As regards typhoid bacilli the 

 case is different, for the same investigators found 

 that in ordinary unsterilised aerated water these 

 bacteria can live as long as eleven days. In 

 seltzer water their vitality is not so marked, but 

 even then it greatly exceeds that of the accom- 

 modating cholera microbes, extending to five 

 days. 



Thus supposing typhoid bacilli to be present 

 in the water employed for the manufacture of 

 aerated waters and we cannot afford to disregard 

 such a possibility we have no guarantee that 

 such waters will be safe for drinking purposes 

 unless a considerable period has been allowed to 

 elapse between their production and consumption. 



It was considerations of this kind which led 

 M. Duclaux, the accomplished director of the 

 Paris Pasteur Institute, to write now some years 

 ago : " Contentons-nous de conclure que 1'usage de 

 Peau de seltz, recommand6 en temps d'epidemie 

 peut en effet etre recommandable, surtout si on 

 laisse vieillir 1'eau quelques jours. On a chance 

 d'y voir diminuer ou meme perir les germes 

 nuisibles." 



On the whole, therefore, the scientific report on 

 bacteria and artificially aerated waters may be 

 regarded as a reassuring one. It is to be re- 

 gretted, however, that in England we do not 



