  Using both a recent calculation by Bruch of the damping of the motion of a
monolayer nitrogen film oscillating harmonically on a metallic surface due to
Ohm's law heating and a Thomas-Fermi approximation treatment of the Ohm's law
heating mechanism, which accounts for the nonzero thickness of the surface
region of a metal, it is argued that this mechanism for friction is able to
account for recent measurements of the drop in the friction for anitrogen film
sliding over a lead substrate as it goes below its superconducting transition
temperature. Bruch's calculation is also made more transparent by re-doing the
calculation for a film sliding at constant speed, instead of oscillating. Using
this treatment, it is easily shown that Bruch's calculation is equivalent to
integrating Boyer's solution of the problem of a charge sliding over a metallic
surface over the charge density of the monolayer nitrogen film.
