The adherence of colloidal hematite onto silver and mercury electrodes is studied employing different deposition and electrochemical potential perturbation techniques. The time response of the attachment process is much shorter than that for particle transfer to a region close to the electrode surface and is strongly influenced by the electrode potential. The influence of the latter manifests itself within a few seconds and in a reversible way in as much as the particles are not driven away from the electrode surface by Other external forces.