76 



JOSEPH HALL BODINE. 



FIG. 2. Curves show the titratable acidity and Ph of an ordinary hay infusion 

 culture, prepared with boiled hay, filtered hay infusion and tap water. A = titrat- 

 able acidity. B Ph. Abscissas time in days indicated. Ordinates at left 

 represent Ph. Ordinates at right represent cubic centimeters o.oi N NAOH 

 required to neutralize 5 c.c. of culture. 



FIG. 3. Curves show the titratable acidity and alkalinity and the Ph of an 

 ordinary hay infusion culture and of a hay infusion culture to which a piece of 

 marble has been added. A = culture prepared with boiled hay, hay infusion, 

 tap water, piece of marble and inoculated with organisms. B = culture prepared 

 with hay infusion, tap water and inoculated with organisms. Volume of cultures, 

 5 liters. 



Top Curves show titratable acidity and alkalinity. O = alkalinity. = 

 acidity. Abscissas, time in days indicated. Ordinates represent cubic centimeters 

 o.oi N NAOH and H2SO4 to neutralize 5 c.c. of culture. 



Bottom Curves show Ph of cultures. Abscissas, time in days indicated' 

 Ordinates represent Ph. 



