The saturated vapour pressure of ether may be measured using the apparatus below. A small omount of ether is let into the vacuum above a mercury column. The ether will partially evaporate and the ether vapour will exert a pressure, depressing the mercury column.
The decrease in the height, h, can be measured with a ruler on the side of the mercury barometer. The saturated vapour pressure of ether is then P=%rho gh where h is the drop in the height of the mercury column.