On the force of effective molecular action

should then be the value of the minimum repulsive ordinate, that obtains when x=3r, in the curve for water at the point of ebullition (2120 F.). This result gives for this curve k=4·931. In this curve the same molecular repulsion occurs again at x=1l5r. Now taking 1581 for the ratio of expansion by volume of water converted into steam at 212 0 F., and for the distance between the effective molecules of the steam, 1151', and putting y= distance of the inner surface of the effective envelope from the center of the molecule, I have