18 Mr. J. N. Hearder on Electrical Conductwity. 
Note.—The battery being applied to the electrometer without 
any of the wires in circuit, the fluid in the stem rose to 176°. 
These experiments were repeated at various intervals with 
wires made indiscriminately from such samples as were at hand, 
though not with any idea of testing variations in the conducting 
power of different samples of the same metal ; hence the relation 
between the order of the results was not always the same, as will 
be seen by the following set of experiments, in which a different 
set of wires were employed :— 
Table I. 
Wires in the bulb of Degrees indicated 
the thermometer. on the scale. 
Gepper oie. ta) 24. agent ESO 
TAC ahd: eet oC iy LO 
Brass - vy AO. ES pe 
Plating. 3.54). 20 0 IS 
Mint . de BOA ee TOG 
Tron’ 4. 64 GA UG 
Bead ign AGS haat A ns 
Table Ii. 
Wires introduced Degrees on thermo-electrometer 
into the circuit. containing copper wire. 
Circuit completed without wire. 150 
Coppers.) GL. BONG, Ailes 
Zing 225), (wee eee 
Brags ‘si: £8 07 1 BLS. OI ee 
Sas 0 8 es ARE OR OS Ge 
Platinium. <v! Pegaso al. 2 how 
Trowii*:! 2.3: 4S AU ooo 
Lead’. y+ G7? RAS Se a ee 
The discrepancy in these results, though perplexing at the 
time, is now easily accounted for, when it is considered that even 
samples of copper wire vary as much in their conducting power 
as 50 to 120. 
On employing two electrometers in consecutive circuit, in 
one of which was inserted a stout copper wire, and in the other 
the various metals in succession, it was curious to observe the 
fluid stand. highest in both when the best conductors were used, 
and lowest with the worst; whilst on employing a similar 
arrangement for transmitting the charge of an electrical battery 
the order was reversed, each electrometer giving the highest 
when the other gave the lowest results. 
Whilst experimenting on one occasion with the various wires 
externally to the electrometer, I had the curiosity to bring my 
finger in contact with the wire to ascertain its temperature. I 
