Abstract: A compound windshield wiper having a blade assembly consisting of a main wiper blade and an adjacent and secondary reciprocating blade in slideable registry therewith. The secondary blade, slideable attached to the main blade by an interlocking bearing-in-slot assembly, is driven towards an extended position during the wiper's arcuate sweep along the windshield, thus allowing the secondary blade, called a traveler blade, to clean portions of the windshield that are normally uncleaned by the traditional windshield wiper blade system. The means for extending the secondary blade comprises a simple cable system that both extends and retracts the secondary blade. The cable may be driven by either a motor means that is synchronized with the wiper sweep, similar to or identical with modern vehicle wiper system motors or, by anchoring the terminus of the cable (the proximal end) to some point of the window frame or vehicle body.