1913-14.] The Hall and Transverse Thermomagnetic Effects. 211 
The ten copper wires from this junction box were led to a small 
distributing board (fig. 3). Two similar moving coil galvanometers 
were used, and these were connected to the distributing board through 
the keys P x and P 2 . The measured low resistances S x and S 2 formed 
portions of the galvanometer circuits and served as potentiometer wires. 
They carried currents supplied by the accumulators V 1 and V 2 , and 
regulated by the resistance boxes R x and R 2 . 
One of the measuring circuits was connected to the contacts H and I 
Fig. 3. 
on the distributing board, and the other to the contacts J and K ; the 
galvanometers could thus be easily connected to any of the couples or 
to the separate wires of different couples. 
Method of Observation. 
Thermomagnetic Effects. 
The brass tubes were supplied respectively with aniline vapour and 
steam, or aniline vapour and cold water, or steam and cold water, as the 
case might be, so as to produce the required temperature gradient, and 
the jackets were supplied with cold water or steam according to circum- 
stances. When the plate had attained a steady state, the temperatures at E, 
B, and D were determined by means of the corresponding thermocouples. 
