^Z(M^C - a substitute forjchlorine? 



By J. E. FULLER, J. C DICKERMAN 

 and A. O. CASTRABERTI* 



LOUIS PASTEUR, the great French 

 scientist, made the first of his 

 discoveries in the field of micro- 

 biology about the time that our 

 Civil War was coming to an end. 

 The development of modern micro- 

 biology may be said to date from that 

 time. 



Beginning with Pasteur's discover- 

 ies, scientific research has produced 

 much valuable information on mi- 

 crobes that cause human and animal 

 diseases. Control of these micro- 

 organisms to safeguard the public 

 health has done much to make 

 people healthier and their lives hap- 

 pier. 



Water-borne Bacteria 



The public-health practice of con- 

 trolling and treating public water sup- 

 plies has prevented the spread of in- 

 fectious diseases, particularly typhoid 

 fever, dysentery, and cholera, by 

 this medium. In 1857, before any- 

 thing specific was known about bac- 

 teria, a cholera epidemic occurred in 

 Philadelphia among people using 

 water that came from a particular 

 town pump. Fifteen years later, a 

 water-borne epidemic of typhoid 

 fever was studied and described in 

 Switzerland. The bacteria causing 

 these diseases were discovered not 

 long after. 



Once the relation of bacteria to 

 water-borne diseases was known, 

 the next step was to find a way to 



* Research Professor, former Assistant Professor, 

 graduate student, respectively, Bacteriology. 



destroy these bacteria and other 

 dangerous microorganisms in pub- 

 He water supplies. Water was first 

 treated with chlorine in Germany 

 about 1894, and in England three 

 years later. The first successful use 

 of chlorine in the United States was 

 in Chicago in 1908. Since that time, 

 the chlorination of public water sup- 

 plies has become general and suc- 

 cessful throughout the United States 

 and in the more progressive coun- 

 tries of the world. 



Chlorination Not Perfect 



Although chlorination is effective, 

 it has certain disadvantages. In par- 

 ticular, it combines with organic 

 matter in water to cause disagree- 

 able tastes and sometimes odors. To 

 avoid these faults, ozone, a form of 

 oxygen, has been considered as a 

 possible substitute for chlorine. 



Ozone, employed somewhat in 

 Europe for treatment of water, is 

 used in the United States princi- 

 pally for the elimination of tastes 

 and odors. Ozone has germicidal 

 properties, but because of the types 

 of generators available, the ozona- 

 tion of water costs much more than 

 chlorination. 



New Generator 



Recently, a simple type of ozon- 

 ator that eliminates several com- 

 plicated steps previously required in 

 ozone production was made avail- 

 able to the University laboratory 



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