ADDENDUM 179 



J. \V. M'LEOD,yiwr. of Path, and Bact., 1912, XVI, p. 321. 

 J. W. M'L,EOD,/0wr;2. of Path, and Bact., 1915, XIX, p. 392. 

 C. E. NORTH, B. WHITE and O. T. AvERY,/0r. of Infect. Diseases, 1914 



xiv, p. 124. 



E. C. ROSENOW, Journ. of Infect. Diseases, 1912, XI, p. 338. 

 C. F. RUEDIGER, Amer. Journ. of Public Health, 1912, II, p. 107. 

 STOWELL, MILLIARD and SCHLESINGER, Journ. of Infect. Diseases, 1913, 



xn, p. 144. 



2. Water. Report of Second Committee on tJie Standardization 

 of Methods for the Bacterioscopic Examination of Water. 



Both Committees were appointed by the Royal Institute 

 of Public Health. The first reported in 1904 and the second 

 in 1914. Dr Houston was the Chairman of the second Com- 

 mittee. 



The procedures recommended do not differ essentially from 

 those advocated in Chapter III except in minor details. Certain 

 procedures in regard to which there is considerable variation 

 of procedure amongst bacteriologists at the present time may 

 be quoted in extenso. 



The Committee recommended that in all cases the number 

 of bacteria present in the water should be estimated, and the 

 number of Bacillus colt. They recommended that as many as 

 possible of the following tests should be employed : 



"(i) Number of microbes per cubic centimetre in : 



(a) Meat broth gelatine (or, when the climatic con- 

 ditions render it necessary, meat broth agar), 

 incubated at 20 to 22 C. 



(b) Meat broth agar incubated at 37 C. 



Brand's Essence of Beef or Lemco may, if desired, 

 be substituted for meat broth in the preparation of 

 these media (a) and (b). 



(c) Lactose bile salt agar (MacConkey). Incubated at 

 37 C. 



The medium may be tinted either with litmus or 

 with neutral red, according to taste. 



122 



