J. Boussinesq, Four short summary papers in the CR, two papers in Liouville's Journal. Boussinesq seems to have drawn heavily on previous work by Bourlet. He has the advantage that he only considers linearized equations. Only the mass of the rear frame is taken into account, and again, the trail is zero. In principle, the derived equation is able to explain in a qualitative way how a bicycle is steered and balanced with a prescribed steer input, but the discussion is not so clear about the way a rider really control the bicycle. Three means are considered: changing the forward speed, steer input and lateral shifting of body weight. Indeed, control theory was only developed in later years. JPM, Nottingham, 5 September 2007.