Comment on "Observation of thermally induced potential in a superconductor"

The interpretation suggested by Falco for his observation of a charge-imbalance potential in superconductors that is apparently linear in $\left|\overrightarrow{\nabla }T\right|$ is questioned. Possible alternative interpretations are suggested, which attribute the observed potential to a term in $\frac{d^{2}T}{d{x}^2}$ or to thermoelectric effects in the normal electrode. The latter appears to be excluded by experimental tests in the Falco experiment, but the former remains a possibility to be tested in further work.