The linear Stark effect is investigated, using the old quantum theory and the equations of motion of the electron in orbital variables. In contrast to the well-known solution in terms of parabolic coordinates, the new form has a simple geometric interpretation, namely, perturbation by the uniform electric field leads in the first approximation to a slow regular precession of the electron orbit around the direction of the field (subject to a single additional condition). This geometric picture outwardly resembles electron orbits precessing around a uniform magnetic field in the normal Zeeman effect.