On the measurement of the radiant energy of infrared lamps, the thermopile trial produced by Electrical Experiment Station, Osaka-Branch and pin-pon-ball thermometer are used in this experiment. Temperature showed by pin-pon-ball thermometer y, is the function of the room temperature x, and constant a, due to the radiant energy, that is, y=a+x. The relation of a(°C) and the radiant energy W (watt/cm²) is W=0.000928a^1.47.
As the room temperature becomes high and the chicks glow, the required energy by the chicks decreases. Then it is the most econcmical method that the room temperature are raised and change the radiant energy to the heat so as to rise the room temperature effectively.