To clarify the ability of the barometer to measure the pressure of the atmosphere, Pascal left a barometer at a low elevation in the town of Clermont, in Auvergne, while taking another with him as he climbed the Puy-de-Dôme. The barometric pressure diminished with elevation, as a measure of the weight of the column of overhead air. The University of Clermont-Ferrand, near the Puy de Dôme, is a sister University to OU.