Abstract: A flow sensing apparatus for providing an indication of the presence of an exiting flow stream from a coal processing plant cyclone includes a probe member disposed in the edge of the flow stream, an electronic sensing circuit cooperatively arranged with the probe member in order to provide either a high or a low level signal, depending upon whether the probe member is being contacted by the exiting flow stream or whether such contact is not being made. A display light is cooperatively arranged with the sensing circuit so as to flicker on and off as the exiting flow stream intermittently and irregularly contacts the probe member. The flickering of the display light indicating proper outlet flow from the coal processing plant cyclone while a constantly on condition of the light indicates that flow is not occurring.