CONDUCTIVITIES OF METALS AND ALLOYS AT LOW TEMPERATURES. 399 
was 31"32 centims., corresponding, according to Thayers’ determinations, to 82° - 4 C. 
absolute, and rose during the first 40 minutes to 33'61 centims., corresponding to a 
temperature of 82 0- 9 C. During the next 16 minutes the following measurements 
were taken :— 
h. 
m. 
Elliott B.A. box, 
ratio arms 10 : 1000. 
11 
52 
manometer . 
43 "16 centims. 
11 
54 
compensating leads 
0"0964 ohm (apparent). 
11 
56 
lower coil . . . 
0-8285 „ 
11 
58 
upper „ . . . 
0-8332 „ 
12 
0 
manometer . 
42‘77 centims. 
12 
2 
upper coil 
0"8335 ohm (apparent). 
12 
4 
lower ,, . . . 
0-8295 „ 
12 
6 
compensating leads 
0-0967 „ 
12 
8 
manometer . 
42*51 centims. 
Barometer 7679 centims., temperature 15°*5 C. 
From these observations we deduce that, at a mean pressure of 33'99 centims. of 
mercury at 15°*5 C., or 33‘92 centims. of mercury at 0° C., at sea-level in latitude 45°, 
under which oxygen boils at 82 0, 9 C. absolute on the constant volume hydrogen 
thermometer, the resistances of the coils were :— 
Upper coil 
Lower ,, 
0'8333 — (P0966 = 07367 apparent ohm = 07286 true ohm. 
0-8290-0-0966 = 07324 „ „ = 0‘7243 „ 
The determinations of resistance at the freezing point of water were made by 
placing the brass tube containing the coils at a depth of about 5 centims. in clean ice 
shavings contained in a brass can with boles in the bottom to allow the ice to drain. 
After the apparatus had stood for half an hour the following observations were 
made:— h 
m. 
0 compensating leads 
2 lower coil 
4 upper ,, ... 
6 ,, ,, ... 
8 lower ,, ... 
10 compensating leads 
From these observations we deduce that the resistances of the coils at the melting 
O 
point of ice were :— 
1 
1 
1 
1 
1 
1 
0"1152 ohm (apparent). 
2-8 7 7 ohms ,, 
2-882 „ 
2-882 „ 
2h77 „ 
0"1153 ohm 
Upper coil 
Lower ,, 
2’882 — 0-115 = 2767 apparent ohms = 2736 true ohms. 
2-877-0-115 = 2762 „ „ = 2731 „ 
In the resistance determinations at the boiling point of water the coils with the 
brass rod through them were placed in a narrow brass tube 12 centims. long, the top 
