45 
of Edinburgh, Session 1872 - 73 . 
(a) Fine Iron Wire. 
Weight on each 
end of Wire. 
Weight required 
to overcome stiff- 
ness of Wire. 
4,000 grains 
170 grains 
5,000 „ 
200 „ 
7,000 „ 
230 „ 
Roller used is 1J in. diameter. 
12,000 „ 
270 „ 
15,000 „ 
280 „ 
22,000 „ 
300 „ 
(6) Fine Copper Wire, annealed over a gas flame. 
1000 grains 
27 grains 
2000 „ 
40 „ 
3000 „ 
50 „ 
4000 „ 
56 „ 
5000 „ 
60 „ 
8000 „ 
64 „ 
The results which immediately follow were obtained from annealed 
and unannealed wires, of the same gauge, of two very different kinds 
of copper — crown 
being of very high, C of very low, thermal and 
electric conductivity. 
(0 
Soft C Wire. 
5,100 grains 
1240 grains 
9,100 „ 
1300 „ 
22,100 „ 
1370 „ 
40,100 „ 
1400 „ 
Soft Crown Wire. 
5,100 grains 
1340 grains 
9,100 „ 
1400 „ 
22,100 „ 
1500 „ 
40,100 „ 
1560 „ 
(«) 
Hard C Wire. 
5,100 grains 
1400 grains 
12,100 „ 
1540 „ 
22,100 „ 
1740 „ 
41,100 „ 
1900 „ 
