382 MICRO-ORGANISMS IN WATER 



Animal Experiment. — On November 9, 1892, 0*6 c.c. 

 of the water (to which broth was added on November 7,. 

 1892) from flask '4 I, Thames water, steam-sterihsed, 

 and infected with anthrax on March 18, 1892, exposed 

 to 151 hours' sunshine,' was subcutaneously injected 

 into a white mouse. The mouse remained alive. 



Animal Experiment. — On November 9,1892, 0*6 c.c. 

 of the water (to which broth was added on Novem- 

 ber 7, 1892) from flask ' 4 I, Thames water, porcelain- 

 filtered, and infected with anthrax on March 18, 1892, 

 exposed to 151 hours' sunshine,' was subcutaneously 

 injected into a white mouse. The mouse remained 

 alive: 



Thus in these waters exposed to direct sunshine for 

 151 hours the anthrax germs were completely destroyed^ 

 and could not he revived by the addition of broth. 



The destruction of anthrax spores by direct sunshine 

 is a subject which, as we have seen, has received the 

 attention of a number of observers. Thus, Arloing 

 (' Compt. rend.,' vol. c, 1885, p. 378, and vol. ci. 

 p. 511) found that they were destroyed in two hours, 

 whilst in subsequent experiments in which the spores 

 were placed in broth maintained at a temperature of 

 4°~11° C. by means of ice five hours' insolation effected 

 their destruction. Eoux (' Ann. de ITnst. Past.,' 1887, 

 p. 445) again insolated the spores when dispersed in 

 the aqueous humour of the ox-eye, and found them 

 destroyed in from twenty-nine to fifty-four hours, whilst 

 Pansini ('Eivista d' Igiene,' 1889) observed their de- 

 struction on potatoes in from four to five hours, in 

 gelatine in from six to seven hours, and in broth in 

 from thirty minutes to two hours. Ward (' Proc. Eoy. 

 Soc.,' vol. lii. p. 393) has also more recently demon- 

 strated their destruction in from two to six hours when 

 insolated in agar-agar, exposed in circular glass dishes. 



