Organosiloxanes containing ester derivatives of ascorbic acid are disclosed having the formula nRSi\u2014X-A wherein R is an alkyl group containing 1 to 6 carbon atoms, n is 1 to 3 inclusive, X is a divalent organic linking group, A is an ester derivative of ascorbic acid. Each foil subassembly comprises a first compliant foil, a second compliant foil, and a spring foil, and subtending a rotational segment, less than all, of the inner surface of the retaining member. The pulsed laser beam includes a pulse duration including a range less than about 50 \u03bcs, an energy per pulse having a range less than about 0. Uniquely, the control unit includes a sensor that is operably associated with the pump for sensing the position of the wiper arm as it moves upwardly and downwardly relative to the glass surface and for controllably energizing the pump at selected positions of the wiper drive arm so that the washer fluid is always dispensed forwardly of the wiper blade to avoid smearing.