274 Dr. G. Gore. Relations of 'Heat to Voltaic and 



As rise of temperature diminishes in certain cases the chemico- 

 electric potential of a metal in an electrolyte (see Table XI, p. 273), 

 this fact may suggest the idea that when a metal is thermo-electro- 

 negative in a particular liquid its degree of rapidity of corrosion is 

 lessened by rise of temperature. This question was subsequently 

 investigated (see p. 285). 



By first comparing the orders of the chemico-electric series (Table X) 

 of metals in hot solutions of potassic bromide and chloride, side by side 

 with each other, and then those in hot solution of potassic cyanide 

 and dilute sulphuric acid, similarly, the influences of small and of 

 great difference of chemical composition of the liquid were con- 

 spicuously seen. In the former case only four of the metals were 

 altered in position, whilst in the latter ten were displaced. The 

 differences also between the orders of the series obtained with dilute 

 hydrochloric acid and solution of potassic chloride, each at 60 F., 

 were much greater than between those obtained with that acid or 

 that salt at 60 and 160 F. A much greater effect was produced in 

 these cases by a difference of liquid than by one of 100 F. of tem- 

 perature. 



With the object of ascertaining the effect of increased strength of 

 liquid upon the order of the chemico-electric series of metals in elec- 

 trolytes at 60 F., a similar set of experiments to those employed in 

 constructing Table X were made. The strengths of solutions were 

 the same as those used in making the thermo-electric determinations 

 of Table IV (p. 259). 



Table XIII. Chemico-electric Series of Metals in Strong Solutions 



(at 60 F.). 



