ANTISEPTICS 



139 



TABLE 28 



Effect of crystal violet on Streptococcus lactis in broth cultures. 

 (Original data.) 



9 6 7 8 hOMrs 3 4 5 6.7 8 hours 



Fig. 26. Different types of antiseptic action. Left: multiplication 

 curves of Bad. coH obtained with various concentrations of rivanol, 

 a dye which increases the lag period but does not affect the growth 

 rate; the curves are parallel. Right: multiplication curves of Bact. coli 

 obtained with various concentrations of sulfathiazole, a dye which 

 retards the growth rate, but does not affect the lag; the curves spread 

 out fan-shaped. In the two graphs the oxygen consumption is con- 

 sidered a measure of the number of organisms. Abscissa: time in 

 hours; ordinate: oxygen consumption, on logarithmic scale. (From data 

 of Hirsch, 1942.) 



