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Thermogalvanic corrosion is a form of galvanic action in which metal dissolves from one surface and deposits on another as the result of a temperature difference between the two surfaces. An apparatus was constructed for measuring the thermogalvanic potential developed by carefully purified nickel powder in several concentrations of neutral nickel sulfate solution under temperature differentials up to 100°C.Reproducible values of the thermodynamic potential were obtained, and were found to vary more or less linearly with temperature difference and exponentially with nickel concentration. The hotter nickel surface was always negative with respect to the colder surface, thus having a tendency to corrode anodically. Under average conditions the thermogalvanic potential developed was about 0.89 millivolts per °C.The standard potential of the nickel electrode was computed from isothermal measurements against a calomel electrode, and found to be approximately −0.232 volt on the normal hydrogen scale.

Several soda‐lime‐silica glasses were melted in which up to 8.52 wt% zinc oxide was substituted for calcium and magnesium oxide. Sonic Young's modulus and Charpy impact resistance measurements were made. The results indicated that an increase of 8.52 wt % zinc oxide reduced the Young's modulus by 9.0% and increased the impact resistance of the soda‐lime‐silica glass by 4.1%.

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