Abstract
The surface temperature of a body is equal to the temperature of the measuring junction of a thermocouple, if this temperature has been, by heating or by cooling, so adjusted that the meter in the couple circuit does not deflect when the measuring junction makes a brief contact with the surface being measured. The validity of this principle was confirmed experimentally by measuring a surface whose true surface temperature was known independently. The new method does not sensibly affect the surface conditions as long as the junction is very small in comparison with the object being measured and the contact is short and light. It was shown that the temperature rise due to the proximity of the measuring junction was negligible in the case of a 0.4‐mm thick glass sheet or the human skin. The new method can give the correct surface temperature even when radiation comes from above or from below. Consequently the opacity of the surface layer does not matter as in the case of the radiation pyrometry.