Peltier and Thomson Effects for Bismuth Crystals

The Peltier and Thomson effects are directly measured (the former against copper) in single crystal rods almost covering the entire orientation range. For the first effect the Voigt-Thomson symmetry relation is definitely not substantiated, while for the latter the data do not provide an adequate test, though it appears likely that there is a deviation here also.The following values are found: at a temperature of 27^∘{}C, π(∥vs.⊥)=13.8, π(45^∘vs.⊥)=8.6 microvolts; at a temperature of 48.5^∘{}C, σ_∥-σ_⊥=43, σ₄₅-σ_⊥=26.5 microvolts/^∘{}C. These values are all in fair agreement with values deduced from thermal e.m.f. temperature data of the writers and of previous observers.