Le télescope pyrhéliométrique de Charles Féry et la mesure de la température du Soleil.

The article focuses on the history of Féry pyrheliometric telescope that was re-discovered during an inventory at ESPCI Paris. Topics discussed include the measurement of the surface temperature of the Sun with the help of the instrument in 1906; its innovative design that was builds upon earlier models of pyrometers conceived by physicist Charles Féry; its traditional Newton-like optical reflecting telescope which was outfitted with a thermocouple; and how it was operated by astronomer Gaston Millochau at the top of the mont Blanc.