For pt. I see ibid., vol. 6, p. 2219 (1976). A re-investigation of the specific heat anomaly at 50K in Pd-H (for an alloy with H/Pd= 0.63) has shown that the magnitude of the anomaly depends on the rate of temperature change used in the specific heat measurement-the slower the rate, the larger the anomaly. Measurements of the spontaneous heat released by the Pd-H sample after sudden cooling to temperatures in the 50K region have yielded information on a thermal relaxation in Pd-H with'fast'and'slow'relaxation times and a common activation energy of (1.98+ or-0.03)* 10 3 J g-atom-1 of H. The measurements indicate that for the 50K transition in Pd-H, diffusion of the hydrogen atoms is an important, and possibly the controlling, step.