Magnetic Permeability of various Alloys of Tron. (6) 
2°8 microhms per ¢.c. is produced by a rise in the carbon from 0:028 to 0:14 per 
cent. ; this would indicate an increase of 2°5 microhms in the specific resistance 
for every tenth per cent. of carbon added in these low carbon steels. The last six 
Be eel At 
ee aa en 
| 4 ; A 
LS) 
As) 
~ 
S 
tw 
5S 
G 
(oy) 
N 
ies) 
) 
5 “70 77 72 73 
Fer-centage of Carbon x /0. 
Fie. 2, 
specimens in Series A show that an increased resistance of 3:0 microhms is pro- 
duced by a rise in the carbon from 0°78 to 1:23 per cent.; this gives an increase 
in the specific resistance of 0°66 microhms for every tenth per cent. of carbon 
TRANS. ROY. DUB. SO€., N.S. VOL. VII., PART IV. N 
