Thermoelectric Anomaly Near a Critical Point

New measurements on $\beta$-brass reveal an anomaly in the thermopower in the vicinity of the order-disorder phase transition. A simple analysis, which is applicable to a wide class of phase transitions, suggests that the anomaly arises from the scattering of conduction electrons from short-range critical fluctuations and that the thermopower can, in principle, provide a direct measure of correlation functions.