SCIENCE-ADVERTISEMENTS 



for the 



Chemist, Biologist and Bacteriologist 



The Bovie H-ion Potentiometer facilitates the determination of acidity or 

 alkalinity of solutions. 



The indications of the instrument are given directly in terms of 

 H-ion concentration. 



The actual reaction of a solution for a given condition may be 

 determined by a single reading, or a curve may be developed 

 (semi-automatically) showing the changes in the actual reac- 

 tion with changes in the condition of the solution. 

 A curve so developed gives data for determining the total reac- 

 tion of the solution. 



This instrument especially facilitates the work of the bac- 

 teriologist in adjusting the reaction of culture media to some 

 definite value. 



The standard cell, galvanometer, and rheostat of the potentiometer circuit 

 are contained within the instrument. External pieces required are a storage 

 or dry cell and the electrodes with their accessories. 



Bulletin S767 describes the Bovie H-ion Potentiometer. 



LEEDS & NORTHRUP COMPANY 



4901 Stenton Ave., 



Electrical Measuring Instruments 



Philadelphia, Pa. 



