BACTERIOLOGY AND WATER in 



was used, i.e. water previously deprived of all 

 bacterial life, only from ten to thirty microbes 

 were present. But an important and far too little 

 recognised factor in the manufacture of aerated 

 waters is the contamination which so frequently 

 takes place subsequent to the initial purification 

 of the water by sterilisation. In some instances 

 this contamination is due to the storing of water 

 before use in reservoirs, where an excellent oppor- 

 tunity is offered for microbial multiplication. 



Merkel found water which originally only 

 boasted of from four to five bacteria per cubic 

 centimetre, subsequently, when ready for distribu- 

 tion as seltzer water, contained considerably over 

 3,000. In this case storage had been resorted 

 to. Again, insufficient importance is attached to 

 the efficient cleansing of the syphons on their 

 return to the factory. The experiments made by 

 Slater in this country and Abba in Italy have 

 conclusively shown that the gaseous aeration of 

 water exerts an inhibitory action on the growth 

 of at least some varieties of water bacteria, for 

 both these investigators found that in proportion 

 as the amount of gas present was diminished by 

 being allowed to escape, so was the multiplica- 

 tion of the bacteria present promoted and their 

 numbers increased. Unsavoury as may be the 

 idea of swallowing down myriads of even harmless 



