110 Dr. Matthiessen on an Alloy which may be used 
Calling the mean of the values at 0° of the hard-drawn wires 
100, we find that, as Table IL. shows, the differences between 
the conducting powers of the alloys are very small, in fact, that 
the greatest is only 1:6 per cent. 
Table IT. 
No, of alloy. Hard-drawn. Difference, Annealed. Difference. 
Lacishesdsttins 100°3 + 03 edd Wavat 1006 + 03 
) eon 1DO*2. | hag AO 3. vi ceen cents be 100-7. +. © 
abatenencdcd O85 *) pets eee ence 992 — Ill 
2 RECN ACHE Mul COSee SeeweT Sivenciswences . 100°'2 — O71 
Dnt ten fahcee 100°45))--. 0G 7G. HAS 100°7 + O04 
Bs Bear cmecias 99°F = Ro) oe sents : 998 — 08 
Wis. cSacaateee cs 100°3.. WO ea ae eas 100°8 + 0° 
Siastccericls: TOR ee esc certenae 1004 + O1 
The great concordance in the above results is partially due to 
the wire drawing so very well. It draws as well as, if not better 
than, any wire | have as yet tried. 
For the sake of comparison, I will give in Table III. the values 
found by different experimenters for the metals with which the 
others are usually compared. 
Table ITI. 
Becquerel *. Siemensf. Matthiessen. 
Lenz}. 
Seal Annealed, vicina Annealed. Has | Annealed. 
HLVED ska ns 100°0| 107:0 100°0 10070; 108-8 | 100°0; 110-0 
Copper ...| 95°3 97°8 73°3 89°7 95:2 99°35; 102°0 
Gald. «.... 68°9 70°0 58°'5 dances D hshes ee 78°0 80°0 
Mercury... 1:86 3°42 at 18°°7 1°72 1:63 at 22°°8 
When no temperature is given, the observations have been 
made at 0° C. 3 | 
Part of these differences may be due to the silver, which in 
some cases may not have been chemically pure; but if any of the 
others be taken as unit, we do not arrive at any better result. 
Table LV. shows the differences between annealed and hard- 
drawn wires,—the annealed being the better conductor, accord- 
ing to— 
‘ Table IV. 
7 
2 
1 
Becquerel, 
a 
0 per cent. 
‘6 per cent. 
‘6 per cent. 
Siemens. 
8°8 per cent. 
6°1 per cent. 
eee ee estes eeeee 
Matthiessen, 
Holzmann §. 
10-0 per cent. 
2°5 per cent. 
2°6 per cent. 
* Ann. de Chim. et de Phys. vol. xvii. (1846), p. 242. 
t+ Pogg. Ann. vol. xxxiv. p. 418, and vol. xlv. 105. 
TOG, BAe. § Phil. Trans. 1860 
i 
