Influence of Stress on Electrical Conductivity of Metals, 635 



As already pointed out, one would expect in the event 

 of a partial reunion of the electrolytic gas by the platinum 

 spray, to find an excess of oxygen in B and hydrogen 

 in C. 



The details of the experiments are given below, where it will 

 be noticed that there is no separation of this kind ; on the con- 

 trary, there is a minute excess of oxygen in G and hydrogen 

 in B. One is, therefore, bound to conclude that any recom- 

 bination which takes place through this cause has no appre- 

 ciable influence on the results. 



Total volume of 



Gas collected 



in B. 



tp -, f 1 Total volume of 



-rr t &:> • -o i Gas collected 

 Hydrogen in B. j ^ c 



Excess of 

 Oxygen in C. 



6-0 c.c. 



12-0 c.c. 



4 c.c. 



025 c.c. 40 c.c. 



1 



037 cc. 9-0 c.c. 



trace 2 - 5 c.c. 



042 c.c. 

 0495 c.c. 

 trace 



The University, Manchester. 



LV. On the Influence of Stress on the Electrical Conductivity 

 of Metals. By TV. Ellis Williams, B.Sc, Research Fellow 

 of the University of Wales *• 



THE effect of hydrostatic pressure in altering the electrical 

 resistance of metals was discovered by Chwolson f in 

 1880, and his results were soon afterwards confirmed by 

 Tomlinson ±. In both cases, however, the range of pressure 

 employed was too small to enable accurate measurements to 

 be made. The question lias, in recent years, been taken up 

 by Lussana§ and also by E. Lissell ||. 



The results obtained by Lissell were : — That the resistance 

 of all the pure metals investigated is diminished by hydro- 

 static pressure, and that the diminution is nearly but not 

 quite proportional to the pressure. He found further that 

 with alloys the decrease of resistance is much smaller than 

 with the pure metals, and that with some alloys the re- 

 sistance is increased by pressure. He paid special attention 

 to the case of manganin, in which he found the increase to be, 

 within the limits of his experiments, accurately proportional 



* Communicated bv Prof. E. Taylor Jones, D.Sc. 



+ Chwolson, Bull. ^Petersburg, 1880. 



X Tomlinson, Phil. Trans. 1883. 



§ Lussana, Nuovo Cimento, (4) x. p. 73, (3) v. p. 305, 1903. 



II Lissell, Diss. Upsala, 1902. 



