514 
MR. 0. W. RICHARDSON ON THE ELECTRICAL CONDUCTIVITY 
Pressure of gas in 
millims. of merciuy. 
Resistance of hot wire 
in ohms. 
Current from wire 
to cylinder, 
1 =• ampere x 10“'-*. 
Temperature of wire 
in ° C. 
•023 
8-338 
8 • 335 
2-52 
1031 
•02.5 
8-438 
8-430 
8-28 
1058 
•021 
8-642 
8-625 
30-6 
1105 
1 
1 
1 
O 1 
9 
8-795 
8-782 
100-5 
1146 
•024 
8-894 
8-875 
188 
1170 
•028 
8-969 
8-950 
300 
i 
1190 1 
•028 
9-106 
9-088 
728 
1224 
•032 
9-163 
9-131 
858 
1243 
•032 
9-263 
9 • 230 
1,414 
1269 
•037 
9-381 
9-350 
2,600 
1298 
•044 
9-472 
9 • 445 
4,025 
1323 
•063 
9 • 603 
9-574 
11,320"^ 
1354 
•063 
9-925 
9-883 
11,740* 
1445 
The next table nives aiiotlier series of observations extendiiiii’ over a hipher ranu'e 
o o o o 
of temperature. Owing to the greater unsteadiness of the tube at the higher 
temperatures the points do not fall quite so accurately on the curve. The current at 
1600° was the liiggest measured and corresponded to U03 X 10“^ ampere per 
sq. centim. of platinum surface. 
* The ciuTeiit Iieciime rather unsteady here. 
