RALPH S. LILLIE 



125 



Fig. 2, Graphs for the second set of determinations with No. 25 wires. Other- 

 wise as in Fig. 1. The circles represent the averages of Table V. 



Fig. 3. Relation between complete recovery time and concentration of acid. 

 Ordinates are times (minutes) required for recovery of complete transmissivity 

 at 20°; abscissae are concentrations (volumes per cent of 1.42 HNO3). The right 

 hand curve represents the earlier (data of Table II), the left hand the later set 

 of determinations. 



