1. In a bicycle brake light, a brake light switch comprising: a metal shaft positioned generally parallel to a radius of the sprocket; a bracket fastened to the bicycle frame, including means pivotally supporting the inner end of said shaft so that the outer end thereof may swing toward or away from the sprocket; spring means urging the outer end of said shaft toward the sprocket; a small wheel, having a metal hub and a frictional surface, said hub being rotatably disposed on the outer end of said shaft with the wheel surface engaging the sprocket; a fixed contact and a fixed stop supported from said shaft in circumferentially spaced positions thereon, adjacent said metal hub, said contact being insulated from said shaft; a metallic finger secured to said hub in a slidingly rotatable relationship relative thereto, said finger being adapted to engage either said contact or said stop, depending upon the direction of rotation of said wheel; and and means for completing an electrical circuit through said shaft, said finger, and said contact, when said finger engages said contact.

7. An electric switch for indicating the reversal of rotation of a wheel, compriSing: a metal shaft; a wheel including a metallic hub rotatable on said shaft, said hub having an annular opening in one end thereof; an arcuately curved wire disposed within said annular opening in sliding engagement with a circumferential groove formed in one wall thereof through an angle of more than 180*, one end of said wire being turned across said opening to form a finger; a fixed contact and a fixed stop supported from said shaft and projecting into said annular opening, said stop being located within the arc of said wire and said contact being located outside the arc, whereby in one direction of rotation of said wheel said finger engages said contact and in the other direction of rotation said finger engages said stop; and means for completing an electrical circuit between said contact and said shaft when said finger engages said contact.