ee at ys og tsi a Aa ak 
E. H. Hall—fotational Coefficients of Metals. 217. 
Gold. 
Numbers proportional 
Temperature. to transverse effect. 
30° 2 ©, 1738 
pa | 1703 
2°°6 1748 
30°°0 1746 
No attempt was made to determine the absolute magnitude. of 
the rotational coefficient in this specimen of gold, so that the 
numbers given in the second column must not be used for 
comparison with numbers elsewhere given as proportional to 
the rotational coefficient in gold or other metals. 
magnetic field in these experiments had an intensity of 
about 1900 C.G. S. The primary current was not measured in 
absolute units. It was such asa Bunsen cell yields in a circuit 
of a few ohms resistance. 
From the above table we get: 
Numbers proportional 
Temperature. to transverse effect. 
30°:2 ‘i 1738 
aie t so 1 ae i742 
he | "~ 1703 
ey ey, 1748 t 1726 
The mean of the numbers at low temperature is therefore less 
than the mean for the higher temperature by rather less than 
one per cent. The particularly small number 1703, which 
u 
transverse effect for a fall of about 30°C., I think it better to 
say that we have here detected no certain effect of fall of 
temperature. 
* This Journal, Sept., 1880. 
4m. Jour. 8c1.—Tuirp Series, VoL. XXV, No. 147.—Marcu, 1883, 
15 
