The adsorption from solution of n‐decylamine on five metals has been measured using a new method, which consists of adsorbing radioactively labeled organic compounds on a metal tape electrode and measuring the reulting radioactivity from the tape. After calibration of the counters and determination of the roughness factor of the tapes by the B.E.T. method using krypton, the amount adsorbed per actual square centimeter is calculated. The coverage has been determined as a function of potential and bulk concentration, and the free energy of adsorption has been calculated for each system. A consideration of thermodynamic cycles for water and for the organic absorbate leads to a relationship between the free energy of adsorption and the solubility and vapor pressure of the organic compound. The adsorption arises largely from metal‐adsorbate dispersion interaction differences between water and the organic. These vary little with the metal. The potential dependence arises primarily from the field dependence of the metal‐water interaction.