SPECIAL EXAMINATIONS 



351 



Annual Report (page 7) shows the influence of rainfall in 

 the Thames valley on the average daily flow of the River 

 Thames, and on the bacterial content of the raw river 

 water : 



Note. The figures in bold type exceed their respective averages. 



II. Search for B. Coli. For this purpose MacConkey's 

 broth is used of the composition neutral-red, bile-salt, 

 peptone, glucose water,* in single, double, triple and quad- 

 ruple strengths. The proper quantities are put into 

 suitable sized tubes, and fermentation or Durham's tubes 



* Just as neutral-red, bile-salt peptone, lactose, agar has been 

 shortened to rebipelagar (see p. 350), so MacConkey's broth with 

 the various carbohydrates might be written thus : 



Neutral-red, bile-salt, peptone, glucose water (aqua) as rebipegluqua. 



lactose rebipelaqua. 



