Page:Proceedings of the Royal Society of London Vol 60.djvu/461

Rh different resistance-temperature-field curves. The lower the temperature the less is the strength of field which will bring the bismuth back to its original resistance when not cooled and not in the field.

The observations have been set out graphically in the diagrams in figs. 1, 2, and 3, and it will be seen that there are in fig. 1 four curves. Each of these curves corresponds to a different temperature, viz., that of liquid air ( — 185° C.), liquefying carbonic acid in ether ( — 79° C.), ordinary temperatures (20° C.), and a fourth shorter curve, which corresponds to a very low temperature of —203° 0., obtained by Electrical Resistivity of Electrolytic Bismuth. Fig. 1.

evaporating liquid air under a reduced pressure. This last curve is only continued for a short distance. These curves show the mode of variation of the resistance of the bismuth at a constant temperature as a function of the transverse magnetic field; and they show how